Category Archives: P-gp

4T1, angiogenesis, Anti-angiogenic, Anti-cancer, anti-inflammatory, Anti-metastatic, anti-tumor, anti-tumor activity, apoptosis, Autophagy, Breast cancer, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Chemotherapy, Colon Cancer or Colorectal cancer, CT-26, cytotoxic, ERK, G1, growth-inhibitory, immunomodulating, Immunosuppressive activity, induces apoptosis, K562, MCF-7, MCF-7/TAM, MDR, MDR-1, MDR-1, Multi-Drug Resistance, Multi-drug resistance, neuro-protective, Oral cancer, P-gp, p21, p27, PR, S, SAS, tamoxifen resistance, TICs, VEGF, VEGF

Tetrandrine

Cancer:
Breast, leukemia, Oral cancer, renal cell carcinoma, colon

Action: Anti-inflammatory, tamoxifen resistance, cell-cycle arrest, anti-metastatic, MDR

Tetrandrine, a bisbenzylisoquinoline alkaloid from the root of Stephania tetrandra (S, Moore), exhibits a broad range of pharmacological activities, including immunomodulating, anti-hepatofibrogenetic, anti-inflammatory, anti-arrhythmic, anti-portal hypertension, anti-cancer and neuro-protective activities (Li, Wang, & Lu, 2001; Ji, 2011). Tetrandrine has anti-inflammatory and anti-fibrogenic actions, which make tetrandrine and related compounds potentially useful in the treatment of lung silicosis, liver cirrhosis, and rheumatoid arthritis (Kwan & Achike, 2002).

Tetrandrine generally presents its anti-cancer effects in micromolar concentrations. Tetrandrine induces different phases of cell-cycle arrest, depends on cancer cell types (Kuo & Lin, 2003; Meng et al., 2004; Ng et al., 2006) and also induces apoptosis in many human cancer cells, including leukemia, bladder, colon, hepatoma, and lung (Lai et al., 1998; Ng et al., 2006; Wu et al., 2010; He et al., 2011).

In vivo experiments have also demonstrated the potential value of tetrandrine against cancer activity. For example, the survival of mice subcutaneously inoculated with CT-26 cells is extended after daily oral gavage of 50 mg/kg or 150  mg/kg of tetrandrine (Wu et al., 2010). Tetrandrine also inhibits the expression of VEGF in glioma cells, has cytotoxic effect on ECV304 human umbilical vein endothelial cells, and suppresses in vivo angiogenesis (Chen et al., 2009). Tetrandrine-treated mice (10  mg/kg/day) have fewer metastases than vehicle-treated mice, and no acute toxicity or obvious changes can be observed in the body weight of both groups (Chang et al., 2004).

Leukemia

Tetrandrine citrate is a novel orally active tetrandrine salt with potent anti-tumor activity against IM-resistant K562 cells and chronic myeloid leukemia. Tetrandrine citrate-induced growth inhibition of leukemia cells may be involved in the depletion of p210Bcr-Abl mRNA and β-catenin protein (Xu et al., 2012).

Comparative in vitro studies show that tetrandrine has significantly greater suppressive effects on adherence, locomotion and 3H-deoxyglucose uptake of neutrophils, as well as the mitogen-induced lymphocyte responses and mixed lymphocyte reactions. By contrast, berbamine demonstrated a significantly greater capacity for inhibition of NK cell cytotoxicity. These results show that tetrandrine is superior to berbamine in most aspects of anti-inflammatory and immunosuppressive activity.

Since these two alkaloids differ by only one substitution in the side chain of one of the benzene rings, these findings may provide further insight into structure-activity relationships and clues to the synthesis and development of active analogues of this promising class of drugs for the treatment of chronic inflammatory diseases (Li et al., 1989).

MDR, Breast Cancer

Tetrandrine also has been found to have extensive pharmacological activity, including positive ion channel blockade and inhibition of multiple drug resistance proteins. These activities are very similar to that of salinomycin, a known drug targeting breast cancer initiation cells (TICs). Tetrandrine has been probed for this activity, targeting of breast cancer TICs. SUM-149, an inflammatory breast cancer cell line, and SUM-159, a non-inflammatory metaplastic breast cancer cell line, were used in these studies.

In summary, tetrandrine demonstrates significant efficacy against in vitro surrogates for inflammatory and aggressive breast cancer TICs (Xu et al., 2011).

Leukemia, MDR

The potential mechanism of the chemotherapy resistance in acute myeloid leukemia (AML) is the multi-drug resistance (MDR-1) gene product P-glycoprotein (P-gp), which is often overexpressed in myeloblasts from acute myeloid leukemia. In a multi-center clinical trial, 38 patients with poor risk forms of AML were treated with tetrandrine (TET), a potent inhibitor of the MDR-1 efflux pump, combined with daunorubicin (DNR), etoposide and cytarabine (TET–DEC). Overall, postchemotherapy marrow hypoplasia was achieved in 36 patients. Sixteen patients (42%) achieved complete remission or restored chronic phase, 9 achieved partial remission (PR) and 13 failed therapy.

These data indicate that TET–DEC was relatively well tolerated in these patients with poor risk AML, and had encouraging anti-leukemic effects (Xu et al., 2006).

Tamoxifen

Tetrandrine (Tet) had a significant reversal of tamoxifen drug resistance breast cancer cells resistant (MCF-7/TAM). The non-cytotoxic dose (0. 625 microg/mL) reversed the resistance by 2.0 folds. MRP1 was reduced at gene (P <0.05) and protein levels when Tet effected on MCF-7ITAM cells. Tet could reverse the drug resistance of MCF-7/TAM cells, and the reverse mechanism may be related to down-regulating MRP1 expression (Chen & Chen, 2013).

Colon Cancer

Tetrandrine (TET) exhibits anti-colon cancer activity. Gao et al. (2013) compared TET with chemotherapy drug doxorubicin in 4T1 tumor-bearing BALB/c mice model and found that TET exhibits anti-cancer metastatic and anti-angiogenic activities better than those of doxorubicin. Local blood perfusion of tumor was markedly decreased by TET after 3 weeks.

Mechanistically, TET treatment leads to a decrease in p-ERK level and an increase in NF- κ B levels in HUVECs. TET also regulated metastatic and angiogenic related proteins, including vascular endothelial growth factor, hypoxia-inducible factor-1 α, integrin β 5, endothelial cell specific molecule-1, and intercellular adhesion molecule-1 in vivo (Chen & Chen, 2013).

Tetrandrine significantly decreased the viability of SAS human oral cancer cells in a concentration- and time-dependent manner. Tet induced nuclear condensation, demonstrated by DAPI staining, and induces apoptosis and autophagy of SAS human cancer cells via caspase-dependent and LC3-I and LC3-II “American Typewriter”; “American Typewriter”;‑dependent pathways (Huang et al., 2013).

Renal Cancer

Tetrandrine treatment showed growth-inhibitory effects on human renal cell carcinoma (RCC) in a time- and dose-dependent manner. Additionally, flow cytometric studies revealed that tetrandrine was capable of inducing G1 cell-cycle arrest and apoptosis in RCC cells. Tet triggered apoptosis and cell-cycle arrest in RCC 786-O, 769-P and ACHN cells in vitro; these events are associated with caspase cascade activation and up-regulation of p21 and p27 (Chen, Ji, & Chen, 2013).

References

Chang KH, Liao HF, Chang HH, et al. (2004). Inhibitory effect of tetrandrine on pulmonary metastases in CT26 colorectal adenocarcinoma-bearing BALB/c mice. American Journal of Chinese Medicine, 32(6):863–872.


Chen HY, Chen XY. (2013). Tetrandrine reversed the resistance of tamoxifen in human breast cancer MCF-7/TAM cells: an experimental research. Zhongguo Zhong Xi Yi Jie He Za Zhi, 33(4):488-91.


Chen T, Ji B, Chen Y. (2013). Tetrandrine triggers apoptosis and cell-cycle arrest in human renal cell carcinoma cells. J Nat Med.


Chen Y, Chen JC, Tseng SH. (2009). Tetrandrine suppresses tumor growth and angiogenesis of gliomas in rats. International Journal of Cancer, 124(10):2260–2269.


Gao JL, Ji X, He TC, et al. (2013). Tetrandrine Suppresses Cancer Angiogenesis and Metastasis in 4T1 Tumor-bearing Mice. Evid Based Complement Alternat Med, 2013:265061. doi: 10.1155/2013/265061.


He BC, Gao JL, Zhang BQ, et al. (2011). Tetrandrine inhibits Wnt/beta-catenin signaling and suppresses tumor growth of human colorectal cancer. Molecular Pharmacology, 79(2):211–219.


Huang AC, Lien JC, Lin MW, et al. (2013). Tetrandrine induces cell death in SAS human oral cancer cells through caspase activation-dependent apoptosis and LC3-I and LC3-II activation-dependent autophagy. Int J Oncol, 43(2):485-94. doi: 10.3892/ijo.2013.1952.


Ji YB. (2011). Active Ingredients of Traditional Chinese Medicine: Pharmacology and Application, People's Medical Publishing House Co., LTD, 2011.


Kwan CY, Achike FI. (2002). Tetrandrine and related bis-benzylisoquinoline alkaloids from medicinal herbs: cardiovascular effects and mechanisms of action. Acta Pharmacol Sin, 23(12):1057-68.


Kuo PL and Lin CC. (2003). Tetrandrine-induced cell-cycle arrest and apoptosis in Hep G2 cells. Life Sciences, 73(2):243–252.


Lai YL, Chen YJ, Wu TY, et al. (1998). Induction of apoptosis in human leukemic U937 cells by tetrandrine. Anti-Cancer Drugs, 9(1):77–81.


Li SY, Ling LH, The BS, Seow WK and Thong YH. (1989). Anti-inflammatory and immunosuppressive properties of the bis-benzylisoquinolines: In vitro comparisons of tetrandrine and berbamine. International Journal of Immunopharmacology, 11(4):395-401 doi:10.1016/0192-0561(89)90086-6.


Meng LH, Zhang H, Hayward L, et al. (2004). Tetrandrine induces early G1 arrest in human colon carcinoma cells by down-regulating the activity and inducing the degradation of G 1-S-specific cyclin-dependent kinases and by inducing p53 and p21Cip1. Cancer Research, 64(24):9086–9092.


Ng LT, Chiang LC, Lin YT, and C. C. Lin CC. (2006). Anti-proliferative and apoptotic effects of tetrandrine on different human hepatoma cell lines. American Journal of Chinese Medicine, 34(1):125–135.


Wu JM, Chen Y, Chen JC, Lin TY, Tseng SH. (2010). Tetrandrine induces apoptosis and growth suppression of colon cancer cells in mice. Cancer Letters, 287(2):187–195.


Xu WL, Shen HL, Ao ZF, et al. (2006). Combination of tetrandrine as a potential-reversing agent with daunorubicin, etoposide and cytarabine for the treatment of refractory and relapsed acute myelogenous leukemia. Leukemia Research, 30(4):407-413.


Xu W, Debeb BG, Lacerda L, Li J, Woodward WA. (2011). Tetrandrine, a Compound Common in Chinese Traditional Medicine, Preferentially Kills Breast Cancer Tumor Initiating Cells (TICs) In Vitro. Cancers, 3:2274-2285; doi:10.3390/cancers3022274.


Xu XH, Gan YC, Xu GB, et al. (2012). Tetrandrine citrate eliminates imatinib-resistant chronic myeloid leukemia cells in vitro and in vivo by inhibiting Bcr-Abl/ β-catenin axis. Journal of Zhejiang University SCIENCE B, 13(11):867-874.

apoptosis, Chapter 7 Isolates and Cancer Research, induces apoptosis, MDR, P-gp

Solanum incanum, solamargine alkaloid

Cancer: Squamous cell

Action: Apoptosis

Solanum incanum is nightshade native to Sub-Saharan Arica and the Middle East.

SR-T100, extracted from the Solanum incanum, contains solamargine alkaloid as the main active ingredient. Thirteen patients, who suffered with 14 actinic keratoses (AKs) were treated with once-daily topical SR-T100 gel and 10 AKs cured after 16 weeks, showing negligible discomforts. Our studies indicate that SR-T100 induces apoptosis of SCC cells via death receptors and the mitochondrial death pathway. The high efficacy of SR-T100 in these preclinical trials suggests that SR-T100 is a highly promising herb for AKs and related disorders (Wu et al., 2011).

Induces Apoptosis

Solamargine (SM), a steroidal glycoalkaloid isolated from the Chinese herb Solanum incanum, has been shown to inhibit the growth of some cancer cell lines and induce significant apoptosis.

SM at concentrations that induce P-gp down-regulation triggered cytotoxicity and apoptosis in MDR K562/A02 cells (Li et al., 2011).

References

Li X, Zhao Y, Ji M, Liu SS, et al. (2011). Induction of actin disruption and down-regulation of P-glycoprotein expression by solamargine in Multi-drug-resistant K562/A02 cells. Chin Med J, 124(13):2038-2044


Wu CH, Liang CH, Shiu LY, et al. (2011). Solanum incanum extract (SR-T100) induces human cutaneous squamous cell carcinoma apoptosis through modulating tumor necrosis factor receptor signaling pathway. J Dermatol Sci, 63(2):83-92.


Yu M, Liu X, Xu B, et al. (2008). Mechanism reversing MDR of K562/A02 by garlicin combined with erythromycin. Zhongguo Shi Yan Xue Ye Xue Za Zhi, 16(5):1044-9.

Anti-cancer, Anti-metastatic, Breast cancer, cardio-protective, CDK, CDK2, CDK4, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, CYP3A, EMT, ER, ER-negative, G0/G1, G1, growth-inhibitory, MDR, metastasis, Multi-Drug Resistance, Multi-drug resistance, NAD(P)H, P-gp, p21, p27, ROS

Schisandrin

Cancer: Leukemia, breast

Action: Anti-metastatic, cardio-protective, MDR, CYP3A, cell-cycle arrest

Leukemia

Schisandrin B (Sch B) has previously been demonstrated to be a novel P-glycoprotein (P-gp) inhibitor. Recent investigation revealed that Sch B was also an effective inhibitor of the multi-drug resistance-associated protein 1 (MRP1). Sch B's ability to reverse MRP1-mediated drug resistance was tested using HL60/ADR and HL60/MRP human promyelocytic leukemia cell lines, with the overexpression of MRP1 but not P-gp. At the equimolar concentration, Sch B demonstrated significantly stronger potency than the drug probenecid, a MRP1 inhibitor (Sun, Xu, Lu, Pan & Hu, 2007).

Up-regulates CYP3A

The ability of Schisandrin B (Sch B) to modulate cytochrome P450 3A activity (CYP3A) and alter the pharmacokinetic profiles of CYP3A substrate (midazolam) was investigated in vivo in treated rats. Rats were routinely administered with physiological saline (negative control group), ketoconazole (75mg/kg, positive control group), or varying doses of Sch B (experimental groups) for 3 consecutive days. Thereafter, changes in hepatic microsomal CYP3A activity and the pharmacokinetic profiles of midazolam and 1′-hydroxy midazolam in plasma were studied to evaluate CYP3A activity.

The results indicated that Sch B had a significant dose-dependent effect on inhibition of rat hepatic microsomal CYP3A activity. These results suggest that a 3-day treatment of Sch B could increase concentration and oral bioavailability of drugs metabolized by CYP3A (Li, Xin, Yu, & Wu, 2013).

Attenuates Metastasis

NADPH oxidase 4 (NOX4) is a potential target for intervention of cancer metastasis, as reactive oxygen species (ROS) generated by this enzyme plays important roles in TGF-β signaling, an important inducer of cancer metastasis. Zhang, Liu & Hu (2013) show that TGF-β induces ROS production in breast cancer 4T1 cells and enhances cell migration; that the effect of TGF- β depends on NOX4 expression; and that knockdown of NOX4 via RNAi significantly decreases the migration ability of 4T1 cells in the presence or absence of TGF-β and significantly attenuates distant metastasis of 4T1 cells to lung and bone.

Sch B significantly suppresses the lung and bone metastasis of 4T1 cells via inhibiting EMT, suggesting its potential application in targeting the process of cancer metastasis. Sch B significantly suppressed the spontaneous lung and bone metastasis of 4T1 cells inoculated s.c. without significant effect on primary tumor growth and significantly extended the survival time of the mice. Sch B did not inhibit lung metastasis of 4T1 cells that were injected via tail vein. Delayed start of treatment with Sch B in mice with pre-existing tumors did not reduce lung metastasis. These results suggested that Sch B acted at the step of local invasion (Liu et al., 2012).

Cardiotoxicity Protective/ Attenuates Metastasis

Sch B is capable of protecting Dox-induced chronic cardiotoxicity and enhancing its anti-cancer activity. To the best of our knowledge, Sch B is the only molecule ever proved to function as a cardio-protective agent as well as a chemotherapeutic sensitizer, which is potentially applicable for cancer treatment.

Pre-treatment with Sch B significantly attenuated Dox-induced loss of cardiac function and damage of cardiomyocytic structure. Sch B substantially enhanced Dox cytotoxicities toward S180 in vitro and in vivo in mice, and increased Dox cytotoxcity against 4T1 in vitro. Although we did not observe this enhancement against the implanted 4T1 primary tumor, the spontaneous metastasis to lung was significantly reduced in combined treatment group compared to Dox alone group (Xu et al., 2011).

Cell-cycle Arrest/Breast Cancer

Schizandrin inhibits cell proliferation through the induction of cell-cycle arrest with modulating cell-cycle-related proteins in human breast cancer cells. Schizandrin exhibited growth-inhibitory activities in cultured human breast cancer cells, and the effect was the more profound in estrogen receptor (ER)-positive T47D cells than in ER-negative MDA-MB-231 cells. When treated with the compound in T47D cells, schizandrin induced the accumulation of a cell population in the G0/G1 phase, which was further demonstrated by the induction of CDK inhibitors p21 and p27 and the inhibition of the expression of cell-cycle checkpoint proteins including cyclin D1, cyclin A, CDK2 and CDK4 (Kim et al., 2010).

References

Kim SJ, Min HY, Lee EJ, et al. (2010). Growth inhibition and cell-cycle arrest in the G0/G1 by schizandrin, a dibenzocyclooctadiene lignan isolated from Schisandra chinensis, on T47D human breast cancer cells. Phytother Res, 24(2):193-7. doi: 10.1002/ptr.2907.


Li WL, Xin HW, Yu AR, Wu XC. (2013). In vivo effect of Schisandrin B on cytochrome P450 enzyme activity. Phytomedicine, 20(8), 760-765


Liu Z, Zhang B, Liu K, Ding Z, Hu X. (2012). Schisandrin B attenuates cancer invasion and metastasis via inhibiting epithelial-mesenchymal transition. PLoS One, 7(7):e40480. doi: 10.1371/journal.pone.0040480.


Sun M, Xu X, Lu Q, Pan Q, Hu X. (2007). Schisandrin B: A dual inhibitor of P-glycoprotein and Multi-drug resistance-associated protein 1. Cancer Letters, 246(1-2), 300-307.


Xu Y, Liu Z, Sun J, et al. (2011). Schisandrin B prevents doxorubicin-induced chronic cardiotoxicity and enhances its anti-cancer activity in vivo. PLoS One, 6(12):e28335. doi: 10.1371/journal.pone.0028335.


Zhang B, Liu Z, Hu X. (2013). Inhibiting cancer metastasis via targeting NAPDH oxidase 4. Biochem Pharmacol, 86(2):253-66. doi: 10.1016/j.bcp.2013.05.011.

anti-apoptotic, Anti-cancer, anti-oxidant, anti-oxidative, apoptosis, Apoptotic, Bcl-2, Chapter 7 Isolates and Cancer Research, IAP, IAP-1, MDR, P-gp, ROS, SGC7901/Adr, TNF, U937, XIAP

Rosmarinic Acid

Cancer: Leukemia

Action: Anti-oxidative, MDR

Leukemia

Because tumor necrosis factor-alpha (TNF-alpha) is well known to induce inflammatory responses, its clinical use is limited in cancer treatment. Rosmarinic acid (RA), a naturally occurring polyphenol flavonoid, has been reported to inhibit TNF-alpha-induced NF-kappaB activation in human dermal fibroblasts. Investigation found that RA treatment significantly sensitizes TNF-alpha-induced apoptosis in human leukemia U937 cells through the suppression of nuclear transcription factor-kappaB (NF-kappaB) and reactive oxygen species (ROS). This inhibition was correlated with suppression of NF-kappaB-dependent anti-apoptotic proteins (IAP-1, IAP-2, and XIAP). RA treatment also normalized TNF-alpha-induced ROS generation. Additionally, ectopic Bcl-2 expressing U937 reversed combined treatment-induced cell death, cytochrome c release into cytosol, and collapse of mitochondrial potential.

Results demonstrated that RA inhibits TNF-alpha-induced ROS generation and NF-kappaB activation, and enhances TNF-alpha-induced apoptosis (Moon, Kim, Lee, Choi, & Kim, 2010).

MDR

The intracellular accumulation of adriamycin, rhodamine123 (Rh123), and the expression of P-glycoprotein (P-gp) were assayed by flow cytometry. The influence of RA on the transcription of MDR1 gene was determined by reverse transcription-polymerase chain reaction. The results showed that RA could reverse the MDR of SGC7901/Adr cells, increase the intracellular accumulation of Adr and Rh123, and decrease the transcription of MDR1 gene and the expression of P-gp in SGC7901/Adr cells (Li et al., 2013).

Anti-cancer

Rosmarinic acid (RA), one of the major components of polyphenol, possesses attractive remedial features. Supplementation with RA significantly reduced the formation of aberrant crypt foci (ACF) and ACF multiplicity in 1,2-dimethylhydrazine (DMH) treated rats. Moreover RA supplementation prevented the alterations in circulatory anti-oxidant enzymes and colonic bacterial enzymes activities. Overall, results showed that all three doses of RA inhibited carcinogenesis, though the effect of the intermediary dose of 5 mg/kg b.w. was more pronounced (Karthikkumar et al., 2012).

References

Karthikkumar V, Sivagami G, Vinothkumar R, Rajkumar D, Nalini N. (2012). Modulatory efficacy of rosmarinic acid on premalignant lesions and anti-oxidant status in 1,2-dimethylhydrazine induced rat colon carcinogenesis. Environ Toxicol Pharmacol, 34(3):949-58. doi: 10.1016/j.etap.2012.07.014.


Li FR, Fu YY, Jiang DH, et al. (2013). Reversal effect of rosmarinic acid on Multi-drug resistance in SGC7901/Adr cell. J Asian Nat Prod Res, 15(3):276-85. doi: 10.1080/10286020.2012.762910.


Moon DO, Kim MO, Lee JD, Choi YH, Kim GY. (2010). Rosmarinic acid sensitizes cell death through suppression of TNF-alpha-induced NF-kappaB activation and ROS generation in human leukemia U937 cells. Cancer Letters, 288(2), 183-191. doi: 10.1016/j.canlet.2009.06.033.

Akt, AMPK, angiogenesis, Anti-angiogenesis, Anti-angiogenic, anti-apoptotic, Anti-cancer, anti-metastasis, Anti-metastatic, anti-tumor, anti-tumor activity, apoptosis, Apoptotic, BAX, Bcl-2, Chapter 7 Isolates and Cancer Research, Chemotherapy, Colon Cancer or Colorectal cancer, enhanced paclitaxel absorption, Glioblastoma, HO-1, HT-29, Lymphoma, MAPK, MDR, metastasis, P-gp, p21, p38, p53, PARP, Pro-apoptotic, Prostate cancer, ROS, S, VEGF, VEGF

RG3 (See also Ginsenosides)

Cancer: Glioblastoma, prostate, breast, colon

Action: Anti-angiogenesis, MDR, enhances chemotherapy, MDR, enhanced paclitaxel absorption, anti-metastatic

RG3 is a ginsenoside isolated from red ginseng (Panax ginseng (L.)), after being peeled, heated, and dried.

Angiosuppressive Activity

Aberrant angiogenesis is an essential step for the progression of solid tumors. Thus anti-angiogenic therapy is one of the most promising approaches to control tumor growth.

Rg3 was found to inhibit the proliferation of human umbilical vein endothelial cells (HUVEC) with an IC50 of 10 nM in Trypan blue exclusion assay.

Rg3 (1-10(3) nM) also dose-dependently suppressed the capillary tube formation of HUVEC on the Matrigel in the presence or absence of 20 ng/ml vascular endothelial growth factor (VEGF). The Matrix metalloproteinases (MMPs), such as MMP-2 and MMP-9, which play an important role in the degradation of basement membrane in angiogenesis and tumor metastasis present in the culture supernatant of Rg3-treated aortic ring culture were found to decrease in their gelatinolytic activities. Taken together, these data underpin the anti-tumor properties of Rg3 through its angiosuppressive activity (Yue et al., 2006).

Glioblastoma

Rg3 has been reported to exert anti-cancer activities through inhibition of angiogenesis and cell proliferation. The mechanisms of apoptosis by ginsenoside Rg3 were related with the MEK signaling pathway and reactive oxygen species. Our data suggest that ginsenoside Rg3 is a novel agent for the chemotherapy of glioblastoma multiforme (GBM) (Choi et al., 2013).

Sin, Kim, & Kim (2012) report that chronic treatment with Rg3 in a sub-lethal concentration induced senescence-like growth arrest in human glioma cells. Rg3-induced senescence was partially rescued when the p53/p21 pathway was inactivated. Data indicate that Rg3 induces senescence-like growth arrest in human glioma cancer through the Akt and p53/p21-dependent signaling pathways.

MDR/Enhanced Paclitaxel Absorption

The penetration of paclitaxel through the Caco-2 monolayer from the apical side to the basal side was facilitated by 20(s)-ginsenoside Rg3 in a concentration-dependent manner. Rg3 also inhibited P-glycoprotein (P-gp), and the maximum inhibition was achieved at 80 µM (p < 0.05). The relative bioavailability (RB)% of paclitaxel with 20(s)-ginsenoside Rg3 was 3.4-fold (10 mg/kg) higher than that of the control. Paclitaxel (20 mg/kg) co-administered with 20(s)-ginsenoside Rg3 (10 mg/kg) exhibited an effective anti-tumor activity with the relative tumor growth rate (T/C) values of 39.36% (p <0.05).

The results showed that 20(s)-ginsenoside Rg3 enhanced the oral bioavailability of paclitaxel in rats and improved the anti-tumor activity in nude mice, indicating that oral co-administration of paclitaxel with 20(s)-ginsenoside Rg3 could provide an effective strategy in addition to the established i.v. route (Yang et al., 2012).

Prostate Cancer

The anti-proliferation effect of Rg3 on prostate cancer cells has been well reported. Rg3 treatment triggered the activation of p38 MAPK; and SB202190, a specific inhibitor of p38 MAPK, antagonized the Rg3-induced regulation of AQP1 and cell migration, suggesting a crucial role for p38 in the regulation process. Rg3 effectively suppresses migration of PC-3M cells by down-regulating AQP1 expression through p38 MAPK pathway and some transcription factors acting on the AQP1 promoter (Pan et al., 2012).

Enhances Chemotherapy

The clinical use of cisplatin (cis-diamminedichloroplatinum II) has been limited by the frequent emergence of cisplatin-resistant cell populations and numerous other adverse effects. Therefore, new agents are required to improve the therapy and health of cancer patients. Oral administration of ginsenoside Rg3 significantly inhibited tumor growth and promoted the anti-neoplastic efficacy of cisplatin in mice inoculated with CT-26 colon cancer cells. In addition, Rg3 administration remarkably inhibited cisplatin-induced nephrotoxicity, hepatotoxicity and oxidative stress.

Rg3 promotes the efficacy of cisplatin by inhibiting HO-1 and NQO-1 expression in cancer cells and protects the kidney and liver against tissue damage by preventing cisplatin-induced intracellular ROS generation (Lee et al., 2012).

Colon Cancer

Rg3-induced apoptosis in HT-29 cells is mediated via the AMPK signaling pathway, and that 20(S)-Rg3 is capable of inducing apoptosis in colon cancer. Rg3-treated cells displayed several apoptotic features, including DNA fragmentation, proteolytic cleavage of poly (ADP-ribose) polymerase (PARP) and morphological changes. 20(S)-Rg3 down-regulated the expression of anti-apoptotic protein B-cell CLL/lymphoma 2 (Bcl2), up-regulated the expression of pro-apoptotic protein of p53 and Bcl-2-associated X protein (Bax), and caused the release of mitochondrial cytochrome c, PARP, caspase-9 and caspase-3 (Yuan et al., 2010).

Anti-metastatic

Studies have linked Rg3 with anti-metastasis of cancer in vivo and in vitro and the CXC receptor 4 (CXCR4) is a vital molecule in migration and homing of cancer to the docking regions. At a dosage without obvious cytotoxicity, Rg3 treatment elicits a weak CXCR4 stain color, decreases the number of migrated cells in CXCL12-elicited chemotaxis and reduces the width of the scar in wound healing and Rg3 is a new CXCR4 inhibitor (Chen et al., 2011).

References

Chen XP, Qian LL, Jiang H, Chen JH. (2011). Ginsenoside Rg3 inhibits CXCR4 expression and related migrations in a breast cancer cell line. Int J Clin Oncol, 16(5):519-23. doi: 10.1007/s10147-011-0222-6.


Choi YJ, Lee HJ, Kang DW, et al. (2013). Ginsenoside Rg3 induces apoptosis in the U87MG human glioblastoma cell line through the MEK signaling pathway and reactive oxygen species. Oncol Rep. doi: 10.3892/or.2013.2555.


Lee CK, Park KK, Chung AS, Chung WY. (2012). Ginsenoside Rg3 enhances the chemosensitivity of tumors to cisplatin by reducing the basal level of nuclear factor erythroid 2-related factor 2-mediated heme oxygenase-1/NAD(P)H quinone oxidoreductase-1 and prevents normal tissue damage by scavenging cisplatin-induced intracellular reactive oxygen species. Food Chem Toxicol, 50(7):2565-74. doi: 10.1016/j.fct.2012.01.005.


Pan XY, Guo H, Han J, et al. (2012). Ginsenoside Rg3 attenuates cell migration via inhibition of aquaporin 1 expression in PC-3M prostate cancer cells. Eur J Pharmacol, 683(1-3):27-34. doi: 10.1016/j.ejphar.2012.02.040.


Sin S, Kim SY, Kim SS. (2012). Chronic treatment with ginsenoside Rg3 induces Akt-dependent senescence in human glioma cells. Int J Oncol., 41(5):1669-74. doi: 10.3892/ijo.2012.1604.


Yang LQ, Wang B, Gan H, et al. (2012). Enhanced oral bioavailability and anti-tumor effect of paclitaxel by 20(s)-ginsenoside Rg3 in vivo. Biopharm Drug Dispos., 33(8):425-36. doi: 10.1002/bdd.1806.


Yuan HD, Quan HY, Zhang Y, et al. (2010). 20(S)-Ginsenoside Rg3-induced apoptosis in HT-29 colon cancer cells is associated with AMPK signaling pathway. Mol Med Rep., 3(5):825-31. doi: 10.3892/mmr.2010.328.


Yue PY, Wong DY, Wu PK, et al. (2006). The angiosuppressive effects of 20 (R)-ginsenoside Rg3. Biochem Pharmacol, 72(4):437-45.

Anti-cancer, anti-proliferative, anti-proliferative effect, Apoptotic, CDC2, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Chemotherapy, G2/M, MDR, Multi-Drug Resistance, Multi-drug resistance, P-gp, ROS, S, Sarcoma

Pheophorbide

Cancer: Liver, lung, uterine sarcoma

Action: MDR

MDR

Pheoborbide is isolated from Scutellaria barbata, a Traditional Chinese Medicine native in southern China, and has been widely used for treating liver diseases.   Pheophorbide a (Pa), an active component from S. barbata, has been shown to have anti-proliferative and Multi-drug-resistant (MDR) effects on the human hepatoma cell line R-HepG2.

Significant reduction of P-glycoprotein expression on Pa-treated R-HepG2 cells was found at both transcriptional and translational levels, leading to reduction of P-glycoprotein activity. In addition, mechanistic study elucidated that Pa induced cell-cycle arrest at G2/M phase and inhibited the expressions of G2/M phase cell-cycle regulatory proteins, cyclin-A1 and cdc2 in a dose-dependent manner (Tang et al., 2007).

Typhonium flagelliforme is an indigenous plant of Malaysia and is used by the local communities to treat cancer. The chemical constituents of Typhonium flagelliforme, particularly those which have anti-proliferative properties towards human cancer cell lines, have been investigated. Purification of the chemical constituents by various chromatographic procedures was guided by the anti-proliferative activity. Four pheophorbide related compounds, namely pheophorbide-a, pheophorbide-a', pyropheophorbide-a and methyl pyropheophorbide-a were identified in the most active fraction, D/F19.

These constituents exhibited anti-proliferative activity against cancer cells and activity increased following photoactivation. However, anti-proliferative activity exhibited by D/F19 alone, relative to the combined effect of pheophorbides and their subfractions, suggests some form of synergistic action between the constituents. The inhibitory effect of D/F19 and the pheophorbides was apoptotic in the absence of light. Most of the chemical constituents identified in this plant have not been reported previously (Lai, Mas, Nair, Mansor, & Navaratnam, 2010).

Prolonged cancer chemotherapy is associated with the development of multi-drug resistance (MDR), which is a major cause of treatment failure. Photodynamic therapy (PDT) has been applied as anti-cancer therapy and a means of circumventing MDR. The anti-proliferative effect of pheophorbide a-mediated photodynamic therapy (Pa-PDT) has been demonstrated in several human cancer cell lines, including the uterine sarcoma cell line, MES-SA.

Combined therapy using Pa-PDT and Dox, a common chemotherapeutic drug, was found to be synergistic in the cell line, MES-SA/Dx5. Both activity and expression of MDR1 and P-gp were reduced by Pa-PDT treatment and such reductions were attenuated by α-tocopherol, the scavenger of reactive oxygen species (ROS), suggesting that the effect of Pa-PDT was mediated by the generation of intracellular ROS (Cheung et al., 2013).

References

Cheung KK, Chan JY, Fung KP. (2013). Anti-proliferative effect of pheophorbide a-mediated photodynamic therapy and its synergistic effect with doxorubicin on multiple drug-resistant uterine sarcoma cell MES-SA/Dx5. Drug Chem Toxicol, 36(4):474-83. doi: 10.3109/01480545.2013.776584.


Lai CS, Mas RH, Nair NK, Mansor SM, Navaratnam V. (2010). Chemical constituents and in vitro anti-cancer activity of Typhonium flagelliforme (Araceae).


Journal of Ethnopharmacology, 127(2), 486-94. doi: 10.1016/j.jep.2009.10.009.


Tang PM, Chan JY, Zhang DM, et al. (2007). Pheophorbide a, an active component in Scutellaria barbata, reverses P-glycoprotein-mediated Multi-drug resistance on a human hepatoma cell line R-HepG2. Cancer Biol Ther, 6(4):504-9.

ABCB1, apoptosis, Cervical cancer, Chapter 7 Isolates and Cancer Research, Commiphora wightii, growth-inhibitory, HL60 and U937, KB-C2, MCF-7, MDA-MB-231, MDR, Multi-Drug Resistance, Multi-drug resistance, P-gp

Guggulsterones

Cancer: Leukemia, cervical cancer

Action: MDR

Guggulsterones are isolated from Commiphora wightii [(Arn.) Bhandari].

Leukemia

The anti-leukemic effects of three isomeric pregnadienedione steroids, cis-guggulsterone, trans-guggulsterone, and 16-dehydroprogesterone, were investigated in HL60 and U937 cells as well as in primary leukemic blasts in culture. Results showed that all three compounds inhibited the proliferation of HL60 and U937 cells, with IC50s ranging from 3.6 to 10.9 µmol/L after treatment for 6 days. These growth-inhibitory effects correlated with externalization of phosphatidylserine and loss of mitochondrial membrane potential., suggesting that these isomeric steroids induce apoptosis in leukemia cells. z-VAD-fmk prevented phosphatidylserine externalization but not mitochondrial membrane potential loss, indicating that mitochondrial dysfunction occurred in the absence of caspase activation.

Interestingly, although all three compounds increased the generation of reactive oxygen species and decreased phosphorylation of extracellular signal-regulated kinase, only cis-guggulsterone induced a rapid depletion of reduced glutathione levels and oxidation of the mitochondrial phospholipid cardiolipin.

Guggulsterones and 16-dehydroprogesterone hence exert anti-leukemic effects via the induction of apoptosis and differentiation and, more importantly, identifies the pregnadienedione structure as a potential chemotherapeutic scaffold (Samudio et al., 2005).

Multi-drug Resistance

Natural phytosterols, such as beta-sitosterol, campesterol, stigmasterol, fucosterol, and z-guggulsterone, are found in foods, herbs, and dietary supplements. The effects of dietary plant sterols on human drug efflux transporters P-glycoprotein (P-gp, ABCB1) and multi-drug resistance protein 1 (MRP1, ABCC1) were investigated using P-gp-overexpressing human carcinoma KB-C2 cells and human MRP1 gene-transfected KB/MRP cells.

The accumulation of daunorubicin or rhodamine 123, fluorescent substrates of P-gp, increased in the presence of guggulsterone in KB-C2 cells. The efflux of rhodamine 123 from KB-C2 cells was inhibited by guggulsterone. Guggulsterone also increased the accumulation of calcein, a fluorescent substrate of MRP1, in KB/MRP cells. The ATPase activities of P-gp and MRP1 were stimulated by guggulsterone.

These results suggest that guggulsterone, a natural dietary hypolipidemic agent, have dual inhibitory effects on P-gp and MRP1 and the potencies to cause food-drug interactions.

References

Nabekura T, Yamaki T, Ueno K, Kitagawa S. (2008). Effects of plant sterols on human Multi-drug transporters ABCB1 and ABCC1. Biochemical and Biophysical Research Communications, 369(2), 363-368. doi: 10.1016/j.bbrc.2008.02.026.


Samudio I, Konopleva M, Safe S, et al. (2005). Guggulsterones induce apoptosis and differentiation in acute myeloid leukemia: identification of isomer-specific antileukemic activities of the pregnadienedione structure. Mol Cancer Ther, 4:1982. doi: 10.1158/1535-7163.MCT-05-0247.

AMPK, Anti-cancer, anti-inflammatory, blocks neurotoxicity, Breast cancer, cAMP, Chapter 7 Isolates and Cancer Research, COX-2, CYP1A1, CYP1A2, HER2, inflammation, MAPK, MDR, neuro-protective, Nitric Oxide, Ovarian cancer, P-gp, p38, Rubia cordifolia, SK-BR-3, SKOV-3

Mollugin

Cancer: Breast, ovarian

Action: Multi-drug resistance, anti-inflammatory, blocks neurotoxicity

Mollugin originally isolated from Rubia cordifolia (L.) is a pharmacological compound for its anti-inflammation, anti-cancer, and anti-viral activity. Mollugin-caused inhibition of phenacetin O-deethylation was concentration-dependent in hierarchical linear models (HLMs), but not time-dependent. In addition, the Lineweaver-Burk plot indicated a typical competitive inhibition. Inhibitory effects of mollugin on human recombinant cDNA-expressed CYP1A1 and 1A2 were comparable. Taken together, the results suggested that mollugin might cause herb-drug interaction through selective inhibition of CYP1A2 in humans receiving herbal medications, including R. cordifolia (Kim et al., 2013).

MDR, Anti-inflammatory

Mollugin treatment significantly inhibited MDR1 expression by blocking MDR1 transcription. P-glycoprotein (P-gp), an important efflux transporter, is encoded by the MDR1 class of genes and is a central element of the multi-drug resistance (MDR) phenomenon in cancer cells. The suppression of MDR1 promoter activity and protein expression was mediated through mollugin-induced activation of AMP-activated protein kinase (AMPK). Furthermore, mollugin inhibited MDR1 expression through the suppression of NF-κB and cAMP-response element binding protein (CREB) activation. These results suggest that mollugin treatment enhanced suppression of P-gp expression by inhibiting the NF-κB signaling pathway and COX-2 expression, as well as attenuating cAMP-response element (CRE) transcriptional activity through AMPK activation (Tran et al., 2013).

Breast Cancer; Ovarian Cancer

Mollugin exhibited potent inhibitory effects on cancer cell proliferation, especially in HER2-overexpressing SK-BR-3 human breast cancer cells and SK-OV-3 human ovarian cancer cells in a dose- and time-dependent manner without affecting immortalized normal mammary epithelial cell line MCF-10A. Mollugin treatment caused a dose-dependent inhibition of HER2 gene expression at the transcriptional level, potentially in part through suppression of NF-κB activation. The combination of mollugin with a MEK1/2 inhibitor may be required in order to achieve optimal efficacy in HER2-overexpressing cancers.

These findings suggest that mollugin is a novel modulator of the HER2 pathway in HER2-overexpressing cancer cells with a potential role in the treatment and prevention of human breast and ovarian cancer with HER2 overexpression (Do et al., 2013).

Blocks Neurotoxicity, Anti-inflammatory

Mollugin also has effects as a neuro-protective agent in glutamate-induced neurotoxicity in the mouse hippocampal HT22 cell line and as an anti-inflammatory agent in lipopolysaccharide-induced microglial activation in BV2 cells. Mollugin showed potent neuro-protective effects against glutamate-induced neuro-toxicity and reactive oxygen species generation in mouse hippocampal HT22 cells.

In addition, the anti-inflammatory effects of mollugin were demonstrated by the suppression of pro-inflammatory mediators, including pro-inflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2) and cytokines (tumor necrosis factor-α and interleukin-6). Furthermore, mollugin also activated the p38 mitogen-activated protein kinase (MAPK) pathway both in HT22 and BV2 cells. These results suggest that mollugin may be a promising candidate for the treatment of neurodegenerative diseases related to neuroinflammation (Jeong et al., 2011).

References

Do MT, Hwang YP, Kim HG, et al. (2013). Mollugin inhibits proliferation and induces apoptosis by suppressing fatty acid synthase in HER2-overexpressing cancer cells. Journal of Cellular Physiology, 228(5):1087–1097. doi: 10.1002/jcp.24258.


Jeong GS, Lee DS, Kim DC, et al. (2011). Neuroprotective and anti-inflammatory effects of mollugin via up-regulation of heme oxygenase-1 in mouse hippocampal and microglial cells. Eur J Pharmacol, 654(3):226-34. doi: 10.1016/j.ejphar.2010.12.027.


Kim H, Choi HK, Jeong TC, et al. (2013). Selective inhibitory effects of mollugin on CYP1A2 in human liver microsomes. Food Chem Toxicol, 51:33-7. doi: 10.1016/j.fct.2012.09.013.


Tran TP, Kim HG, Choi JH, et al. (2013). Reversal of P-glycoprotein-mediated Multi-drug resistance is induced by mollugin in MCF-7/adriamycin cells. Phytomedicine. doi:10.1016/j.phymed.2013.01.014.

Akt, anti-apoptotic, Anti-cancer, anti-inflammatory, anti-proliferative, anti-tumor, apoptosis, Apoptotic, Bcl-2, Breast cancer, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Chemotherapy, Colon Cancer or Colorectal cancer, cytotoxic, epidermal growth factor receptor, G2/M, growth-inhibitory, HepG2, HER-2, HER-2/neu, HER2, HIF, HL-60, HL-60/ADR, induces apoptosis, Induces cytotoxicity, inflammation, JAK2, LS1034, Lung cancer, Mahlavu, PLC/PRF/5 and HepG2, Mcl-1, MDA-MB-231, MDR, MDR-1, MDR-1, MTOR, P-gp, p21, p53, Pancreatic cancer, ROS, S, STAT3

Emodin (See also Aloe-Emodin)

Cancer:
Breast, colon, liver, chemotherapy, myeloma, oral., pancreatic, hepatocellular carcinoma, lung, leukemia

Action: MDR-1, cell-cycle arrest

Emodin is an active natural anthraquinone derivative component of a traditional Chinese and Japanese medicine isolated from the root and rhizomes of Rheum palmatum L., Senna obtusifolia [(L.) H.S.Irwin & Barneby], Fallopia japonica [Houtt. (Ronse Decr.)], Kalimeris indica (L.) Sch.Bip., Ventilago madraspatana (Gaertn.), Rumex nepalensis (Spreng.), Fallopia multiflora [(Thunb.) Haraldson], Cassia occidentalis [(L.) Link], Senna siamea [(Lam.) Irwin et Barneby] and Acalypha australis (L.).

Aloe-emodin is an active natural anthraquinone derivative, and is found in the roots and rhizomes of numerous Chinese medicinal herbs (including Rheum palmatum L) and exhibits anti-cancer effects on many types of human cancer cell lines.

Administration of rhubarb (Emodin) can effectively reverse severe acute pancreatitis (SAP) by regulating the levels of IL-15 and IL-18 (Yu & Yang, 2013).

Pancreatic Cancer

Emodin is a tyrosine kinase inhibitor that has an inhibitory effect on mammalian cell-cycle modulation in specific oncogene-overexpressing cells. Recently, there has been great progress in the preclinical study of the anti-cancer mechanisms of emodin. A recent study revealed that emodin has therapeutic effects on pancreatic cancer through various anti-tumor mechanisms. Notably, the therapeutic efficacy of emodin in combination with chemotherapy was found to be higher than the comparable single chemotherapeutic regime, and the combination therapy also exhibited fewer side-effects (Wei et al., 2013).

Hepatocellular Carcinoma, Pancreatic, Breast, Colorectal and Lung Cancers, and Leukemia

Emodin is found as an active ingredient in different Chinese herbs including Rheum palmatum and Polygonam multiflorum, and has diuretic, vasorelaxant, anti-bacterial., anti-viral., anti-ulcerogenic, anti-inflammatory, and anti-cancer effects. The anti-inflammatory effects of emodin have been exhibited in various in vitro as well as in vivo models of inflammation including pancreatitis, arthritis, asthma, atherosclerosis and glomerulonephritis. As an anti-cancer agent, emodin has been shown to suppress the growth of various tumor cell lines including hepatocellular carcinoma, pancreatic, breast, colorectal., leukemia, and lung cancers. Emodin is a pleiotropic molecule capable of interacting with several major molecular targets including NF-κB, casein kinase II, HER2/neu, HIF-1α, AKT/mTOR, STAT3, CXCR4, topoisomerase II, p53, p21, and androgen receptors which are involved in inflammation and cancer (Shrimali et al., 2013).

Hepatocellular Carcinoma

It has been found that emodin induces apoptotic responses in the human hepatocellular carcinoma cell lines (HCC) Mahlavu, PLC/PRF/5 and HepG2. The addition of emodin to these three cell lines led to inhibition of growth in a time-and dose-dependent manner. Emodin generated reactive oxygen species (ROS) in these cells which brought about a reduction of the intracellular mitochondrial transmembrane potential (ΔΨ m), followed by the activation of caspase–9 and caspase–3, leading to DNA fragmentation and apoptosis.

Preincubation of hepatoma cell lines with the hydrogen peroxide-scavenging enzyme, catalase (CAT) and cyclosporin A (CsA), partially inhibited apoptosis. These results demonstrate that enhancement of generation of ROS, DeltaPsim disruption and caspase activation may be involved in the apoptotic pathway induced by emodin (Jing et al., 2002).

Colon Cancer

In in vitro study, emodin induced cell morphological changes, decreased the percentage of viability, induced G2/M phase arrest and increased ROS and Ca(2+) productions as well as loss of mitochondrial membrane potential (ΔΨ(m)) in LS1034 cells. Emodin-triggered apoptosis was also confirmed by DAPI staining and these effects are concentration-dependent.

In in vivo study, emodin effectively suppressed tumor growth in tumor nude mice xenografts bearing LS1034. Overall, the potent in vitro and in vivo anti-tumor activities of emodin suggest that it might be developed for treatment of colon cancer in the future (Ma et al., 2012).

Myeloid Leukemia

It has been shown that emodin significantly induces cytotoxicity in the human myeloma cells through the elimination of myeloid cell leukemia 1 (Mcl-1). Emodin inhibited interleukin-6–induced activation of Janus-activated kinase 2 (JAK2) and phosphorylation of signal transducer and activator of transcription 3 (STAT3), followed by the decreased expression of Mcl-1. Activation of caspase-3 and caspase-9 was triggered by emodin, but the expression of other anti-apoptotic Bcl-2 family members, except Mcl-1, did not change in the presence of emodin. To clarify the importance of Mcl-1 in emodin-induced apoptosis, the Mcl-1 expression vector was introduced into the human myeloma cells by electroporation. Induction of apoptosis by emodin was almost abrogated in Mcl-1–overexpressing myeloma cells as the same level as in parental cells, which were not treated with emodin. Emodin therefore inhibits interleukin-6–induced JAK2/STAT3 pathway selectively and induces apoptosis in myeloma cells via down-regulation of Mcl-1, which is a good target for treating myeloma. Taken together, these results show emodin as a new potent anti-cancer agent for the treatment of multiple myeloma patients (Muto et al., 2007).

Breast Cancer; Block HER-2

The mechanism by which emodin prevents breast cancer is unknown; however the product of the HER-2/neu proto-oncogene, HER2 has been proposed to be involved. The product of the HER-2/neu proto-oncogene, HER2, is the second member of the human epidermal growth factor receptor (HER) family of tyrosine kinase receptors and has been suggested to be a ligand orphan receptor. Amplification of the HER2 gene and overexpression of the HER2 protein induces cell transformation and has been demonstrated in 10% to 40% of human breast cancer. HER2 overexpression has been suggested to associate with tumor aggressiveness, prognosis and responsiveness to hormonal and cytotoxic agents in breast cancer patients. These findings indicate that HER2 is an appropriate target for tumor-specific therapies.

A number of approaches have been investigated: (1) a humanized monoclonal antibody against HER2, rhuMAbHER2 (trastuzumab), which is already approved for clinical use in the treatment of patients with metastatic breast cancer; (2) tyrosine kinase inhibitors, such as emodin, which block HER2 phosphorylation and its intracellullar signaling; (3) active immunotherapy, such as vaccination; and (4) heat shock protein (Hsp) 90-associated signal inhibitors, such as radicicol derivatives, which induce degradation of tyrosine kinase receptors, such as HER2 (Kurebayashi, 2001).

MDR

The effects of emodin on the nucleoside transport and multi-drug resistance in cancer cells has also been investigated. Nucleoside transport inhibition was determined by thymidine incorporation assay. The cytotoxicity to cancer cells was determined by MTT assay. The pump efflux activity and the expression of P glycoprotein were examined by flow cytometric assay. Emodin was active in the inhibition of nucleoside transport, with an IC 50 value of 9 9 µmol·L -1. Emodin markedly enhanced the cytotoxicity of 5 FU, MMC and MTX against human hepatoma BEL 7402 cells and partly reversed the multi-drug resistance in human breast cancer MCF 7/Adr cells.

Emodin inhibited P-gp pump efflux activity and reduced the expression of P gp in MCF 7/Adr cells. These findings provide a biological basis for the application of emodin as a biochemical modulator to potentiate the effects of anti-tumor drugs and reverse the multi-drug resistance in cancer cells (Jiang et al., 2009).

Cell-cycle Arrest

Large quantities of emodin were isolated from the roots of Rheum emodi and a library of novel emodin derivatives 2–15 were prepared to evaluate their anti-proliferative activities against HepG2, MDA-MB-231 and NIH/3T3 cells lines. The derivatives 3 and 12 strongly inhibited the proliferation of HepG2 and MDA-MB-231 cancer cell line with an IC50 of 5.6, 13.03 and 10.44, 5.027, respectively, which is comparable to marketed drug epirubicin (III). The compounds 3 and 12 were also capable of inducing cell-cycle arrest and caspase dependent apoptosis in HepG2 cell lines and exhibit DNA intercalating activity. These emodin derivatives hold promise for developing safer alternatives to the marketed epirubicin (Narender et al., 2013).

Cell-cycle Arrest; MDR1 & AZT

3'-azido-3'-deoxythymidine (AZT) and emodin altered the cell-cycle distribution and led to an accumulation of cells in S phase. Meanwhile, the expression of MDR1 mRNA/p-gp protein was markedly decreased. These results show a synergistic growth-inhibitory effect of AZT and emodin in K562/ADM cells, which is achieved through S phase arrest. MDR1 might ultimately be responsible for these phenomena (Chen et al., 2013).

References

Chen P, Liu Y, Sun Y, et al. (2013). AZT and emodin exhibit synergistic growth-inhibitory effects on K562/ADM cells by inducing S phase cell-cycle arrest and suppressing MDR1 mRNA/p-gp protein expression. Pharm Biol.


Garg AK, Buchholz TA, Aggarwal BB. (2005). Chemo-sensitization and Radiosensitization of Tumors by Plant Polyphenols. Antioxid Redox Signal., 7(11-12):1630-47.


Jiang XF & Zhen YS. (1999). Reversal of Multi-drug resistance by emodin in cancer cells. Acta Pharmaceutica Sinica, 1999-03.


Jing X, Ueki N, Cheng J, Imanishi H, Hada T. (2002). Induction of apoptosis in hepatocellular carcinoma cell lines by emodin. Cancer Science, 93(8):874–882.


Kurebayashi J. (2001). Biological and clinical significance of HER2 overexpression in breast cancer. Breast Cancer, 8(1):45-51


Ma YS, Weng SW, Lin MW, et al. (2012). Anti-tumor effects of emodin on LS1034 human colon cancer cells in vitro and in vivo: Roles of apoptotic cell death and LS1034 tumor xenografts model. Food Chem Toxicol, 50(5): 1271–1278. doi: 10.1016/j.fct.2012.01.033.


Muto A, Hori M, Sasaki Y, et al. (2007). Emodin has a cytotoxic activity against human multiple myeloma as a Janus-activated kinase 2 inhibitor. Mol Cancer Ther. doi: 10.1158/1535-7163.MCT-06-0605.


Narender T, Sukanya P, Sharma K, et al. (2013). Preparation of novel anti-proliferative emodin derivatives and studies on their cell-cycle arrest, caspase dependent apoptosis and DNA binding interaction. Phytomedicine, 20(10):890-896.


Shrimali D, Shanmugam MK, Kumar AP, et al. (2013). Targeted abrogation of diverse signal transduction cascades by emodin for the treatment of inflammatory disorders and cancer. Cancer Lett:S0304-3835(13)00598-3. doi: 10.1016/j.canlet.2013.08.023.


Wei WT, Lin SZ, Liu DL, Wang ZH. (2013). The distinct mechanisms of the anti-tumor activity of emodin in different types of cancer (Review). Oncol Rep. doi: 10.3892/or.2013.2741.


Yu XW, Yang RZ. (2013). Effects of crude rhubarb on serum IL-15 and IL-18 levels in patients with severe acute pancreatitis. An Hui Yi Xue, 34(3): 285-287.

ABC, anti-apoptotic, Anti-cancer, anti-oxidant, anti-proliferative, anti-tumor, anti-tumor activity, apoptosis, apoptosis induction, apoptosis-inducing, apoptosis-triggering, Apoptotic, BAX, Bcl-2, Breast cancer, Chapter 7 Isolates and Cancer Research, Chemoprevention, Chemotherapy, cytotoxic, induces apoptosis, inhibits proliferation, Leukemia, MDR, Melanoma, Multi-Drug Resistance, Oral cancer, P-gp, Pro-apoptotic, ROS, S, Squamous cell carcinoma

Chelerythrine, Chelidonine and Sanguinarine

Cancer:
Leukemia, oral squamous cell carcinoma, melanoma

Action: Cytotoxic, MDR, apoptosis-triggering, inhibits proliferation

Sanguinarine, chelerythrine and chelidonine are isoquinoline alkaloids derived from the greater celandine. They possess a broad spectrum of pharmacological activities. It has been shown that their anti-tumor activity is mediated via different mechanisms, which can be promising targets for anti-cancer therapy. This study focuses on the differential effects of these alkaloids upon cell viability, DNA damage, and nucleus integrity in mouse primary spleen and lymphocytic leukemic cells, L1210.

Data suggests that cytotoxic and DNA-damaging effects of chelerythrine and sanguinarine are more selective against mouse leukemic cells and primary mouse spleen cells, whereas chelidonine blocks proliferation of L1210 cells. The action of chelidonine on normal and tumor cells requires further investigation (Kaminsky, Lin, Filyak, & Stoika, 2008).

MDR

Cancer cells often develop multi-drug resistance (MDR) which is a multidimensional problem involving several mechanisms and targets. This study demonstrates that chelidonine, an alkaloid extract from Chelidonium majus, which contains protoberberine and benzo[c]phenanthridine alkaloids, has the ability to overcome MDR of different cancer cell lines through interaction with ABC-transporters, CYP3A4 and GST, by induction of apoptosis, and cytotoxic effects.

Chelidonine and the alkaloid extract inhibited P-gp/MDR1 activity in a concentration-dependent manner in Caco-2 and CEM/ADR5000 and reversed their doxorubicin resistance. In addition, chelidonine and the alkaloid extract inhibited the activity of the drug, modifying enzymes CYP3A4 and GST in a dose-dependent manner. The expression analysis identified a common set of regulated genes related to apoptosis, cell-cycle, and drug metabolism.

Results suggest that chelidonine is a promising compound for overcoming MDR and enhancing cytotoxicity of chemotherapeutics, especially against leukemia cells. Its efficacy needs to be confirmed in animal models (El-Readi, Eid, Ashour, Tahrani & Wink, 2013).

Induces Apoptosis, Leukemia

Sanguinarine, chelerythrine and chelidonine possess prominent apoptotic effects towards cancer cells. This study found that sanguinarine and chelerythrine induced apoptosis in human CEM T-leukemia cells, accompanied by an early increase in cytosolic cytochrome C that precedes caspases-8, -9 and -3 processing. Effects of sanguinarine and chelerythrine on mitochondria were confirmed by clear changes in morphology (3h), howerver chelidonine did not affect mitochondrial integrity. Sanguinarine and chelerythrine also caused marked DNA damage in cells after 1h, but a more significant increase in impaired cells occurred after 6h. Chelidonine induced intensive DNA damage in 15–20% cells after 24h.

Results demonstrated that rapid cytochrome C release in CEM T-leukemia cells exposed to sanguinarine or chelerythrine was not accompanied by changes in Bax, Bcl-2 and Bcl-X((L/S)) proteins in the mitochondrial fraction, and preceded activation of the initiator caspase-8 (Kaminskyy, Kulachkovskyy, & Stoika, 2008).

Induces Apoptosis

Chelerythrine, formerly identified as a protein kinase C inhibitor, has also been shown to inhibit the anti-apoptotic Bcl-2 family proteins. Chelerythrine initiates the rapid mitochondrial apoptotic death of H9c2 cardiomyoblastoma cells in a manner that is likely independent of the generation of ROS from mitochondria (Funakoshi et al., 2011).

Oral Cancer, Inhibits cell proliferation

The effects of benzo[c] phenanthridine alkaloids (QBA), known mainly as sanguinarine and chelerythrine, on the inhibition of some kinds of cancer cell proliferation have been established. Sanguinarine is a potential inhibitor of tumorigenesis which suggests that it may be valuable in the development of new anti-cancer drugs for the treatment of oral squamous cell carcinoma (OSCC) (Tsukamoto et al., 2011).

Apoptotic Effects; Melanoma

Mixtures of isoquinoline alkaloids containing protopine, chelidonine, sanguinarine, allocryptopine, and stylopine were applied to murine fibroblast NIH/3T3, mouse melanoma B16F10, and human breast cancer MCF7 cell cultures for 20 and 40 min, and the content of alkaloids in the cell media was measured by capillary electrophoresis (CE). CE separation of isoquinoline alkaloids was performed in 30 mM phosphate buffer (pH 2.5). As these alkaloids have native fluorescence, they were directly detected using the commercially available UV light-emitting diode without fluorescent derivatization. The results showed a differential ability of celandine alkaloids to penetrate into the normal and cancer cell interior, which was inversely proportional to their cytotoxic activity.

While the most effective transport of celandine alkaloids from the cell medium to the cell interior was observed for normal murine fibroblast NIH/3T3 cells (about 55% of total content), cytotoxicity tests demonstrated selective and profound apoptotic effects of a five-alkaloid combination in the mouse melanoma B16F10 cell line (Kulp & Bragina, 2013).

Leukemia

The methanol extract isolated from the greater celandine Chelidonium majus L. (CME) has a strong anti-oxidant potential and exerted the anti-proliferative activity via apoptosis on leukemia cells. CME, due to the presence of the isoquinoline alkaloids and the flavonoid components may play an important role in both cancer chemoprevention through its anti-oxidant activity and modern cancer chemotherapy as a cytotoxic and apoptosis-inducing agent (Nadova et al., 2008).

Apoptosis-inducing Activity

Apoptogenic and DNA-damaging effects of chelidonine (CHE) and sanguinarine (SAN), two structurally related benzophenanthridine alkaloids isolated from Chelidonium majus L. (Papaveraceae), were compared. Both alkaloids induced apoptosis in human acute T-lymphoblastic leukaemia MT-4 cells. Apoptosis induction by CHE and SAN in these cells was accompanied by caspase-9 and -3 activation and an increase in the pro-apoptotic Bax protein. An elevation in the percentage of MT-4 cells possessing caspase-3 in active form after their treatment with CHE or SAN was in parallel to a corresponding increase in the fraction of apoptotic cells. CHE, in contrast to SAN, does not interact directly with DNA.

This fact is in line with DNA-damaging effects of the alkaloids detected in the COMET assay. Nevertheless, apoptosis-inducing activity of CHE even slightly exceeded that of SAN (Philchenkov et al., 2008).

Chelidonium majus L. alkaloids chelidonine, sanguinarine, chelerythrine, protopine and allocryptopine were identified as major components of Ukrain. Apart from sanguinarine and chelerythrine, chelidonine turned out to be a potent inducer of apoptosis, triggering cell death at concentrations of 0.001 mM, while protopine and allocryptopine were less effective. Similar to Ukrain, apoptosis signaling of chelidonine involved Bcl-2 controlled mitochondrial alterations and caspase-activation (Habermehl et al., 2006).

References

El-Readi MZ, Eid S, Ashour ML, Tahrani A, & Wink M. (2013). Modulation of Multi-drug resistance in cancer cells by chelidonine and Chelidonium majus alkaloids. Phytomedicine, 20(3-4), 282-94. doi: 10.1016/j.phymed.2012.11.005.


Funakoshi T, Aki T, Nakayama H, et al. (2011). Reactive oxygen species-independent rapid initiation of mitochondrial apoptotic pathway by chelerythrine. Toxicol In Vitro, 25(8):1581-7. doi: 10.1016/j.tiv.2011.05.028.


Habermehl D, Kammerer B, Handrick R, et al. (2006). Pro-apoptotic activity of Ukrain is based on Chelidonium majus L. alkaloids and mediated via a mitochondrial death pathway. BMC Cancer, 6:14.


Kaminskyy V, Lin KW, Filyak Y, & Stoika R. (2008). Differential effect of sanguinarine, chelerythrine and chelidonine on DNA damage and cell viability in primary mouse spleen cells and mouse leukemic cells. Cell Biology International., 32(2), 271-277.


Kaminskyy V, Kulachkovskyy O,Stoika R. (2008). A decisive role of mitochondria in defining rate and intensity of apoptosis induction by different alkaloids. Toxicology Letters, 177(3), 168-81. doi: 10.1016/j.toxlet.2008.01.009.


Kulp M, Bragina O. (2013). Capillary electrophoretic study of the synergistic biological effects of alkaloids from Chelidonium majus L. in normal and cancer cells. Analytical and Bioanalytical Chemistry, 405(10), 3391-7. doi: 10.1007/s00216-013-6755-y.


Nadova S, Miadokova E, Alfoldiova L, et al. (2008). Potential anti-oxidant activity, cytotoxic and apoptosis-inducing effects of Chelidonium majus L. extract on leukemia cells. Neuro Endocrinol Lett, 29(5):649-52.


Philchenkov A., Kaminskyy V., Zavelevich M., Stoika R. (2008). Apoptogenic activity of two benzophenanthridine alkaloids from Chelidonium majus L. does not correlate with their DNA-damaging effects. Toxicology In Vitro, 22(2), 287-95.


Tsukamoto H, Kondo S, Mukudai Y, et al., (2011). Evaluation of anti-cancer activities of benzo[c]phenanthridine alkaloid sanguinarine in oral squamous cell carcinoma cell line. Anti-cancer Res, 31(9):2841-6.


Zhe C, Li-Juan W, Ming Hui W, et al. (2011). Mechanism governing reversal of Multi-drug resistance in human breast carcinoma cells by chelerythrine. Zhongguo Yi Xue Ke Xue Yuan Xue Bao, 33(1):45-50. doi: 10.3881/j.issn.1000-503X.2011.01.010.

Anti-cancer, anti-inflammatory, AT6.3, Breast cancer, Breast cancer cell lines, Chapter 7 Isolates and Cancer Research, chemo-preventive, Chemotherapy, IKK, inflammation, inhibits NF-κB, MDR, Multi-Drug Resistance, P-gp, PTK, various fruits, vegetables

Biochanin A

Cancer: Breast

Action: Multi-drug resistance, anti-inflammatory, chemo-preventive

Biochanin is a derivative found in fruits, vegetables, plant-derived beverages, and herbal dietary supplements. It is isolated from a range of plants, including red clover, soy, alfalfa sprouts, and garbanzo beans (Trifolium pratense (L.), Glycine max [(L.) Merr.], Medicago sativa (L.), Cicer arietinum (L.))

MDR; Breast Cancer

Multi-drug resistance (MDR) is one of the most significant obstacles in cancer chemotherapy. One of the mechanisms involved in the development of MDR is the over-expression of P-glycoprotein (P-gp). It is widely known that natural compounds found in vegetables, fruits, plant-derived beverages and herbal dietary supplements not only have anti-cancer properties, but may also modulate P-gp activity. To further elucidate this, the effect of biochanin on P-gp function in human breast cancer cell lines, MCF-7 (sensitive) and MCF-7/ADR (resistant) was therefore examined.

The IC50 value of DNM in the resistant cells was about 22 times higher than that in the sensitive cells, indicating an over-expression of P-gp in the resistant cells, MCF-7/ADR. Biochanin was found to significantly decrease the IC50 value of DNM. Biochanin also showed a significant increase in [3H]-DNM accumulation, increasing by 454.3±19.5% in the resistant cells. Moreover, biochanin significantly decreased DNM efflux from MCF-7/ADR cells compared with the control. These results suggest that biochanin may reverse MDR by inhibiting the P-gp function (Chung et al., 2005).

Chemo-preventive

Biochanin A (BCA), a major isoflavone in red clover and many other legumes, has been reported to display estrogenic as well as cancer chemo-preventive properties. Ingested BCA is known to display low bioavailability due to poor solubility, extensive metabolism and rapid clearance. Esters of bioactive isoflavones are known to increase metabolic stability and bioavailability following local rather than systemic administration (Fokialakis et al., 2012).

Anti-inflammatory

Biochanin inhibits NF-κB activation not only by blocking the upstream IKK, but also PTK that phosphorylate tyrosine residues of IκBα. The double-edged sword effect of inhibition of NF-κB via inhibition of both serine/threonine kinase and PTK by biochanin might show useful therapeutic value against activities of cells that lead to tumorigenesis and inflammation (Manna et al., 2012).

References

Chung SY, Sung MK, Kim NH, et al. (2005). Inhibition of P-glycoprotein by natural products in human breast cancer cells. Archives of Pharmacal Research, 28(7):823-828. doi: 10.1007/BF02977349


Fokialakis N, Alexi X, Aligiannis N, et al. (2012). Ester and carbamate ester derivatives of Biochanin A: synthesis and in vitro evaluation of estrogenic and anti-proliferative activities. Bioorg Med Chem, 20(9):2962-70. doi: 10.1016/j.bmc.2012.03.012.


Manna SK. (2012). Double-edged sword effect of biochanin to inhibit nuclear factor kappaB: suppression of serine/threonine and tyrosine kinases. Biochem Pharmacol, 83(10):1383-92. doi: 10.1016/j.bcp.2012.02.011.

anti-tumor, Apoptotic, Chapter 7 Isolates and Cancer Research, Chemo-sensitizer, GSTP1, MDR, Multi-drug resistance, Multi-drug resistance reversal, P-gp, Radix Angelica sinensis

Coniferyl Ferulate

Cancer: Lung

Action: Multi-drug resistance reversal

MDR

Glutathione S-transferase (GST) is a key enzyme in the development of multi-drug resistance (MDR) in tumors. Inhibition of the expression, or activity, of GST has emerged as a promising therapeutic strategy for the reversal of MDR.

Coniferyl ferulate (CF), isolated from the root of Radix Angelica sinensis (RAS), showed strong inhibition of human placental GST. Using the high-throughput screening model, CF's 50% inhibition concentration (IC50) was 0.3   µM, which was greater than the established GSTP1-1 inhibitor, ethacrynic acid (EA).

Moreover, CF showed strong apoptotic activity and could markedly decrease the overexpression of P-gp. The results demonstrated that CF could inhibit GST activity in a concentration-dependent manner and showed a potential MDR reversal effect for anti-tumor adjuvant therapy.

CF demonstrates strong GST inhibitory activity and may serve as a prospective MDR reversal agent in the treatment of cancer. In addition, CF could potentially be used as a promising chemo-sensitizer capable of indirectly regulating P-gp expression via modulation of GST activity, and with fewer adverse effects. Further investigation of CF in anti-tumor adjuvant therapy is warranted (Chen et al., 2013).

Ferulic acid (FA) is widely considered as a biologically active component in Angelica sinensis, and used as one of the marker compounds for the quality control of Angelica sinensis. However, in A. sinensis, FA mainly exists as its ester, coniferyl ferulate (CF). The potency of CF is much higher than that of FA, and the IC50 values for AA, ADP and THR were 7.1 ± 0.3, 276.4 ± 53.4 and 77.5 ± 23.1 µg/ml, respectively (Yu et al., 2009).

References

Chen C, Wu C, Lu X, Yan, Z, Gao, H, Li, S (2013). Coniferyl ferulate, a strong inhibitor of glutathione S-transferase isolated from radix Angelicae sinensis, reverses Multi-drug resistance and downregulates P-glycoprotein. Evidence-Based Complementary and Alternative Medicine, 2013(2013), ID639083. http://dx.doi.org/10.1155/2013/639083.


Yu Y, Lin BQ, Yu L, et al. (2009). Inhibitory Effects of Two Ferulates from Angelica Sinensis on Platelet Aggregation and Oxytocin-induced Uterine Contraction. The Open Bioactive Compounds Journal., 2009, 2, 43-46.