Category Archives: HeLa

Wogonin

Cancer:
Breast, lung (NSCLC), gallbladder carcinoma, osteosarcoma, colon, cervical

Action: Neuro-protective, anti-lymphangiogenesis, anti-angiogenic, anti-estrogenic, chemo-sensitizer, pro-oxidative, hypoxia-induced drug resistance, anti-metastatic, anti-tumor, anti-inflammatory

Wogonin is a plant monoflavonoid isolated from Scutellaria rivularis (Benth.) and Scutellaria baicalensis (Georgi).

Breast Cancer; ER+ & ER-

Effects of wogonin were examined in estrogen receptor (ER)-positive and -negative human breast cancer cells in culture for proliferation, cell-cycle progression, and apoptosis. Cell growth was attenuated by wogonin (50-200 microM), independently of its ER status, in a time- and concentration-dependent manner. Apoptosis was enhanced and accompanied by up-regulation of PARP and Caspase 3 cleavages as well as pro-apoptotic Bax protein. Akt activity was suppressed and reduced phosphorylation of its substrates, GSK-3beta and p27, was observed. Suppression of Cyclin D1 expression suggested the down-regulation of the Akt-mediated canonical Wnt signaling pathway.

ER expression was down-regulated in ER-positive cells, while c-ErbB2 expression and its activity were suppressed in ER-negative SK-BR-3 cells. Wogonin feeding to mice showed inhibition of tumor growth of T47D and MDA-MB-231 xenografts by up to 88% without any toxicity after 4 weeks of treatment. As wogonin was effective both in vitro and in vivo, our novel findings open the possibility of wogonin as an effective therapeutic and/or chemo-preventive agent against both ER-positive and -negative breast cancers, particularly against the more aggressive and hormonal therapy-resistant ER-negative types (Chung et al., 2008).

Neurotransmitter Action

Kim et al. (2011) found that baicalein and wogonin activated the TREK-2 current by increasing the opening frequency (channel activity: from 0.05 ± 0.01 to 0.17 ± 0.06 in baicalein treatment and from 0.03 ± 0.01 to 0.29 ± 0.09 in wogonin treatment), while leaving the single-channel conductance and mean open time unchanged. Baicalein continuously activated TREK-2, whereas wogonin transiently activated TREK-2. Application of baicalein and wogonin activated TREK-2 in both cell attached and excised patches, suggesting that baicalein and wogonin may modulate TREK-2 either directly or indirectly with different mechanisms. These results suggest that baicalein- and wogonin-induced TREK-2 activation help set the resting membrane potential of cells exposed to pathological conditions and thus may give beneficial effects in neuroprotection.

Anti-metastasic

The migration and invasion assay was used to evaluate the anti-metastasis effect of wogonin. Wogonin at the dose of 1–10 µM, which did not induce apoptosis, significantly inhibited the mobility and invasion activity of human gallbladder carcinoma GBC-SD cells. In addition, the expressions of matrix metalloproteinase (MMP)-2, MMP-9 and phosphorylated extracellular regulated protein kinase 1/2 (ERK1/2) but not phosphorylated Akt were dramatically suppressed by wogonin in a concentration-dependent manner. Furthermore, the metastasis suppressor maspin was confirmed as the downstream target of wogonin.

These findings suggest that wogonin inhibits cell mobility and invasion by up-regulating the metastasis suppressor maspin. Together, these data provide novel insights into the chemo-protective effect of wogonin, a main active ingredient of Chinese medicine Scutellaria baicalensis (Dong et al., 2011).

Anti-tumor and Anti-metastatic

Kimura & Sumiyoshi (2012) examined the effects of wogonin isolated from Scutellaria baicalensis roots on tumor growth and metastasis using a highly metastatic model in osteosarcoma LM8-bearing mice. Wogonin (25 and 50mg/kg, twice daily) reduced tumor growth and metastasis to the lung, liver and kidney, angiogenesis (CD31-positive cells), lymphangiogenesis (LYVE-1-positive cells), and TAM (F4/80-positive cell) numbers in the tumors of LM8-bearing mice. Wogonin (10–100µM) also inhibited increases in IL-1β production and cyclooxygenase (COX)-2 expression induced by lipopolysaccharide in THP-1 macrophages. The anti-tumor and anti-metastatic actions of wogonin may be associated with the inhibition of VEGF-C-induced lymphangiogenesis through a reduction in VEGF-C-induced VEGFR-3 phosphorylation by the inhibition of COX-2 expression and IL-1β production in Tumor-associated macrophages (TAMs).

Anti-inflammatory

Wogonin extracted from Scutellariae baicalensis and S. barbata is a cell-permeable and orally available flavonoid that displays anti-inflammatory properties. Wogonin is reported to suppress the release of NO by iNOS, PGE2 by COX-2, pro-inflammatory cytokines, and MCP-1 gene expression and NF-kB activation (Chen et al., 2008).

Hypoxia-Induced Drug Resistance (MDR)

Hypoxia-induced drug resistance is a major obstacle in the development of effective cancer therapy. The reversal abilities of wogonin on   hypoxia resistance were examined and the underlying mechanisms discovered. MTT assay revealed that hypoxia increased maximal 1.71-, 2.08-, and 2.15-fold of IC50 toward paclitaxel, ADM, and DDP in human colon cancer cell lines HCT116, respectively. Furthermore, wogonin showed strong reversal potency in HCT116 cells in hypoxia and the RF reached 2.05. Hypoxia-inducible factor-1α (HIF-1α) can activate the expression of target genes involved in glycolysis. Wogonin decreased the expression of glycolysis-related proteins (HKII, PDHK1, LDHA), glucose uptake, and lactate generation in a dose-dependent manner.

In summary, wogonin could be a good candidate for the development of a new multi-drug resistance (MDR) reversal agent and its reversal mechanism probably is due to the suppression of HIF-1α expression via inhibiting PI3K/Akt signaling pathway (Wang et al., 2013).

NSCLC

Wogonin, a flavonoid originated from Scutellaria baicalensis Georgi, has been shown to enhance TRAIL-induced apoptosis in malignant cells in in vitro studies. In this study, the effect of a combination of TRAIL and wogonin was tested in a non-small-cell lung cancer xenografted tumor model in nude mice. Consistent with the in vitro study showing that wogonin sensitized A549 cells to TRAIL-induced apoptosis, wogonin greatly enhanced TRAIL-induced suppression of tumor growth, accompanied with increased apoptosis in tumor tissues as determined by TUNEL assay.

The down-regulation of these antiapoptotic proteins was likely mediated by proteasomal degradation that involved intracellular reactive oxygen species (ROS), because wogonin robustly induced ROS accumulation and ROS scavengers butylated hydroxyanisole (BHA) and N-acetyl-L-cysteine (NAC) and the proteasome inhibitor MG132 restored the expression of these antiapoptotic proteins in cells co-treated with wogonin and TRAIL.

These results show for the first time that wogonin enhances TRAIL's anti-tumor activity in vivo, suggesting this strategy has an application potential for clinical anti-cancer therapy (Yang et al., 2013).

Colon Cancer

Following treatment with baicalein or wogonin, several apoptotic events were observed, including DNA fragmentation, chromatin condensation and increased cell-cycle arrest in the G1 phase. Baicalein and wogonin decreased Bcl-2 expression, whereas the expression of Bax was increased in a dose-dependent manner compared with the control. Furthermore, the induction of apoptosis was accompanied by an inactivation of phosphatidylinositol 3-kinase (PI3K)/Akt in a dose-dependent manner.

The administration of baicalein to mice resulted in the inhibition of the growth of HT-29 xenografts without any toxicity following 5 weeks of treatment. The results indicated that baicalein induced apoptosis via Akt activation in a p53-dependent manner in the HT-29 colon cancer cells and that it may serve as a chemo-preventive or therapeutic agent for HT-29 colon cancer (Kim et al., 2012).

Breast

The involvement of insulin-like growth factor-1 (IGF-1) and estrogen receptor α (ERα) in the inhibitory effect of wogonin on the breast adenocarcinoma growth was determined. Moreover, the effect of wogonin on the angiogenesis of chick chorioallantoic membrane (CAM) was also investigated. The results showed wogonin and ICI182780 both exhibited a potent ability to blunt IGF-1-stimulated MCF-7 cell growth. Either of wogonin and ICI182780 significantly inhibited ERα and p-Akt expressions in IGF-1-treated cells. The inhibitory effect of wogonin showed no difference from that of ICI182780 on IGF-1-stimulated expressions of ERα and p-Akt. Meanwhile, wogonin at different concentrations showed significant inhibitory effect on CAM angiogenesis.

These results suggest the inhibitory effect of wogonin on breast adenocarcinoma growth via inhibiting IGF-1-mediated PI3K-Akt pathway and regulating ERα expression. Furthermore, wogonin has a strong anti-angiogenic effect on CAM model (Ma et al., 2012).

Chemoresistance; Cervical Cancer, NSCLC

Chemoresistance to cisplatin is a major limitation of cisplatin-based chemotherapy in the clinic. The combination of cisplatin with other agents has been recognized as a promising strategy to overcome cisplatin resistance. Previous studies have shown that wogonin (5,7-dihydroxy-8-methoxyflavone), a flavonoid isolated from the root of the medicinal herb Scutellaria baicalensis Georgi, sensitizes cancer cells to chemotheraputics such as etoposide, adriamycin, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and TNF.

In this study, the non-small-cell lung cancer cell line A549 and the cervical cancer cell line HeLa were treated with wogonin or cisplatin individually or in combination. It was found for the first time that wogonin is able to sensitize cisplatin-induced apoptosis in both A549 cells and HeLa cells as indicated by the potentiation of activation of caspase-3, and cleavage of the caspase-3 substrate PARP in wogonin and cisplatin co-treated cells.

Results provided important new evidence supporting the potential use of wogonin as a cisplatin sensitizer for cancer therapy (He et al., 2012).

References

Chen LG, Hung LY, Tsai KW, et al. (2008). Wogonin, a bioactive flavonoid in herbal tea, inhibits inflammatory cyclooxygenase-2 gene expression in human lung epithelial cancer cells. Mol Nutr Food Res. 52:1349-1357.


Chung H, Jung YM, Shin DH, et al. (2008). Anti-cancer effects of wogonin in both estrogen receptor-positive and -negative human breast cancer cell lines in vitro and in nude mice xenografts. Int J Cancer, 122(4):816-22.


Dong P, Zhang Y, Gu J, et al. (2011). Wogonin, an active ingredient of Chinese herb medicine Scutellaria baicalensis, inhibits the mobility and invasion of human gallbladder carcinoma GBC-SD cells by inducing the expression of maspin. J Ethnopharmacol, 137(3):1373-80. doi: 10.1016/j.jep.2011.08.005.


He F, Wang Q, Zheng XL, et al. (2012). Wogonin potentiates cisplatin-induced cancer cell apoptosis through accumulation of intracellular reactive oxygen species. Oncology Reports, 28(2), 601-605. doi: 10.3892/or.2012.1841.


Kim EJ, Kang D, Han J. (2011). Baicalein and wogonin are activators of rat TREK-2 two-pore domain K+ channel. Acta Physiologica, 202(2):185–192. doi: 10.1111/j.1748-1716.2011.02263.x.


Kim SJ, Kim HJ, Kim HR, et al. (2012). Anti-tumor actions of baicalein and wogonin in HT-29 human colorectal cancer cells. Mol Med Rep, 6(6):1443-9. doi: 10.3892/mmr.2012.1085.


Kimura Y & Sumiyoshi M. (2012). Anti-tumor and anti-metastatic actions of wogonin isolated from Scutellaria baicalensis roots through anti-lymphangiogenesis. Phytomedicine, 20(3-4):328-336. doi:10.1016/j.phymed.2012.10.016


Ma X, Xie KP, Shang F, et al. (2012). Wogonin inhibits IGF-1-stimulated cell growth and estrogen receptor α expression in breast adenocarcinoma cell and angiogenesis of chick chorioallantoic membrane. Sheng Li Xue Bao, 64(2):207-12.


Wang H, Zhao L, Zhu LT, et al. (2013). Wogonin reverses hypoxia resistance of human colon cancer HCT116 cells via down-regulation of HIF-1α and glycolysis, by inhibiting PI3K/Akt signaling pathway. Mol Carcinog. doi: 10.1002/mc.22052.


Yang L, Wang Q, Li D, et al. (2013). Wogonin enhances anti-tumor activity of tumor necrosis factor-related apoptosis-inducing ligand in vivo through ROS-mediated down-regulation of cFLIPL and IAP proteins. Apoptosis, 18(5):618-26. doi: 10.1007/s10495-013-0808-8.

Periplocin

Cancer: Lung, colorectal, leukemia

Action: Apoptosis-inducing, cytostatic effect

Apoptosis

The anti-tumor component of Cortex periplocae is periplocin. Periplocin is one of the cardenolides isolated from cortex periplocae which is used for treatment of rheumatoid arthritis and reinforcement of bones and tendons in traditional medicine.

Periplocin has been reported to inhibit many cell lines, including MCF-7, TE-13, QG-56, SMMC-7721, T24, Hela, K562, TE-13 and Eca-109 cells. Studies have shown that periplocin reduces the expression of survivin, an inhibitor of apoptosis. It also releases caspases-3 and -7 from complexes and thereby increases their activities, ultimately inducing tumor cell apoptosis (Zhao et al., 2009).

Lung Cancer

The anti-tumor activity of periplocin was investigated in lung cancer cells both in vitro and in vivo, and its anti-cancer mechanism was explored. Periplocin inhibited the growth of lung cancer cells and induced their apoptosis in a time- and dose-dependent manner by cell-cycle arrest in G0/G1 phase. Periplocin exhibited anti-tumor activity both in human (A549) and mouse (LL/2) lung cancer xenograft models. Immunohistochemical analysis revealed that intratumoral angiogenesis was significantly suppressed.

Furthermore, anti-cancer activity mediated by periplocin was associated with decreased level of phosphorylated AKT and ERK both in vitro and in vivo, which are important for cell growth and survival. Moreover, periplocin induced apoptosis by down-regulating Bcl-2 and up-regulating Bax, leading to activation of caspase-3 and caspase-9.

These findings suggest that periplocin could inhibit the growth of lung cancer both in vitro and in vivo, which could be attributed to the inhibition of proliferation and the induction of apoptosis signaling pathways, such as AKT and ERK. These observations provide further evidence on the anti-tumor effect of periplocin, and it may be of importance to further explore its potential role as a therapeutic agent for cancer (Lu et al., 2010).

Colorectal Carcinomas

The Wnt/beta-catenin signaling pathway plays an important role in the development and progression of human cancers, especially in colorectal carcinomas. Periplocin extracted from cortex periplocae (CPP) significantly inhibited the proliferation of SW480 cells in a time-and dose-dependent manner (P<0.01). CPP (0.5 microg/mL) also caused G0/G1 cell-cycle arrest of SW480 cells and induced cell apoptosis (P<0.05). Compared to untreated control cells, after the treatment with CPP, the protein levels of beta-catenin in total cell lysates, cytosolic extracts, and nuclear extracts were reduced (P<0.01); the binding activity of the TCF complex in nucleus to its specific DNA binding site was suppressed; mRNAs of the downstream target genes survivin, c-myc and cyclin D1 were decreased (P<0.01) while beta-catenin mRNA remained unchanged.

CPP could significantly inhibit the proliferation of SW480 cells, which may be through down-regulating the Wnt/beta-catenin signaling pathway (Du et al., 2009).

Pro-apoptotic and Cytostatic Effect/Leukemia

Cardenoliddes are steroid glycosides which are known to exert cardiotonic effects by inhibiting the Na(+)/K(+)-ATPase. Several of these compounds have been shown also to possess anti-tumor potential. The aim of the present work was the characterization of the tumor cell growth inhibition activity of four cardenolides, isolated from Periploca graeca L., and the mechanisms underlying such an effect.

The pro-apoptotic and cytostatic effect of the compounds was tested in U937 (monocytic leukemia) and PC3 (prostate adenocarcinoma). Characterization of apoptosis and cell-cycle impairment was obtained by cytofluorimetry and WB. Periplocymarin and periplocin were the most active compounds, periplocymarin being more effective than the reference compound ouabain. The reduction of cell number by these two cardenolides was due in PC3 cells mainly to the activation of caspase-dependent apoptotic pathways, while in U937 cells to the induction of cell-cycle impairment without extensive cell death. Interestingly, periplocymarin, at cytostatic but non-cytotoxic doses, was shown to sensitize U937 cells to TRAIL. Taken together, these data outline that cardiac glycosides are promising anti-cancer drugs and contribute to the identification of new natural cardiac glycosides to obtain chemically modified non-cardioactive/low toxic derivatives with enhanced anti-cancer potency (Bloise et al., 2009).

References

Bloise E, Braca A, De Tommasi N, Belisario MA. (2009). Pro-apoptotic and cytostatic activity of naturally occurring cardenolides. Cancer Chemother Pharmacol, 64(4):793-802. doi: 10.1007/s00280-009-0929-5.


Du YY, Liu X, Shan BE. (2009). Periplocin extracted from cortex periplocae induces apoptosis of SW480 cells through inhibiting the Wnt/beta-catenin signaling pathway. Ai Zheng, 28(5):456-60.


Lu ZJ, Zhou Y, Song Q, et al. (2010). Periplocin inhibits growth of lung cancer in vitro and in vivo by blocking AKT/ERK signaling pathways. Cell Physiol Biochem, 26(4-5):609-18. doi: 10.1159/000322328.


Zhao LM, Ai J, Zhang Q, et al. (2009). Periplocin (a sort of ethanol from Cortex periplocae) induces apoptosis of esophageal carcinoma cells by influencing expression of related genes. Tumor (Chin), 29:1025-1030.

Corosolic acid

Cancer:
Myeloid leukemia, cervical., glioblastoma, gastric, sarcoma

Action: Immunosuppressive activity

Corosolic Acid is isolated from Lagerstroemia speciosa [(L.) Pers.] and Crataegus pinnatifida var. psilosa (C. K. Schneider).

Sarcoma; Immunosuppressive Activity

The results from an in vivo study showed that Corosolic acid (CA) administration did not suppress the tumor proliferation index, but significantly impaired subcutaneous tumor development and lung metastasis.

CA administration inhibited signal transducer and activator of transcription-3 (Stat3) activation and increased in the number of infiltrating lymphocytes in tumor tissues. Ex vivo analysis demonstrated that a significant immunosuppressive effect of MDSC in tumor-bearing mice was abrogated and the mRNA expressions of cyclooxygenase-2 and CCL2 in MDSC were significantly decreased by CA administration.

Furthermore, CA enhanced the anti-tumor effects of adriamycin and cisplatin in vitro. Since Stat3 is associated with tumor progression not only in osteosarcoma, but also in other malignant tumors, these findings indicate that CA might be widely useful in anti-cancer therapy by targeting the immunosuppressive activity of MDSC and through its synergistic effects with anti-cancer agents (Horlad et al., 2013).

Cervical Cancer

Xu et al. (2009) investigated the response of human cervix adenocarcinoma HeLa cells to Corosolic acid (CRA) treatment. These results showed that CRA significantly inhibited cell viability in both a dose- and a time-dependent manner. CRA treatment induced S cell-cycle arrest and caused apoptotic death in HeLa cells. It was found that CRA increased in Bax/Bcl-2 ratios by up-regulating Bax expression, disrupted mitochondrial membrane potential and triggered the release of cytochrome c from mitochondria into the cytoplasm.

These results, taken together, indicate CRA could have strong potentials for clinical application in treating human cervix adenocarcinoma and improving cancer chemotherapy.

Glioblastoma

Tumor-associated macrophages (TAMs) of M2 phenotype promote tumor proliferation and are associated with a poor prognosis in patients with glioblastoma.

The natural compounds possessing inhibitory effects on M2 polarisation in human monocyte-derived macrophages were investigated. Among 130 purified natural compounds examined, corosolic acid significantly inhibited the expression of CD163, one of the phenotype markers of M2 macrophages, as well as suppressed the secretion of IL-10, one of the anti-inflammatory cytokines preferentially produced by M2 macrophages, thus suggesting that corosolic acid suppresses M2 polarisation of macrophages.

Furthermore, corosolic acid inhibited the proliferation of glioblastoma cells, U373 and T98G, and the activation of Signal transducer and activator of transcription-3 (STAT3) and Nuclear Factor-kappa B (NF-κB), in both human macrophages and glioblastoma cells. These results indicate that corosolic acid suppresses the M2 polarisation of macrophages and tumor cell proliferation by inhibiting both STAT3 and NF-κB activation. Therefore, corosolic acid may be a new tool for tumor prevention and therapy (Fujiwara et al., 2010).

Gastric Cancer

Corosolic acid (CRA) suppresses HER2 expression, which in turn promotes cell-cycle arrest and apoptotic cell death of gastric cancer cells, providing a rationale for future clinical trials of CRA in the treatment of HER2-positive gastric cancers. CRA combined with adriamycin and 5-fluorouracil enhanced this growth inhibition, but not with docetaxel and paclitaxel (Lee et al., 2010).

Leukemia

Corosolic acid displayed about the same potent cytotoxic activity as ursolic acid against several human cancer cell lines. In addition, the compound displayed antagonistic activity against the phorbol ester-induced morphological modification of K-562 leukemic cells, indicating the suppression of protein kinase C (PKC) activity by the cytotoxic compound (Ahn et al., 1998).

References

Ahn KS, Hahm MS, Park EJ, Lee HK, Kim IH. (1998). Corosolic acid isolated from the fruit of Crataegus pinnatifida var. psilosa is a protein kinase C inhibitor as well as a cytotoxic agent. Planta Med, 64(5):468-70.


Fujiwara Y, Komohara Y, Ikeda T, Takeya M. (2010). Corosolic acid inhibits glioblastoma cell proliferation by suppressing the activation of signal transducer and activator of transcription-3 and nuclear factor-kappa B in tumor cells and tumor-associated macrophages. Cancer Science. doi: 10.1111/j.1349-7006.2010.01772.x


Horlad H, Fujiwara Y, Takemura K, et al. (2013). Corosolic acid impairs tumor development and lung metastasis by inhibiting the immunosuppressive activity of myeloid-derived suppressor cells. Molecular Nutrition & Food Research, 57(6):1046-1054. doi: 10.1002/mnfr.201200610


Lee MS, Cha EY, Thuong PT, et al. (2010). Down-regulation of human epidermal growth factor receptor 2/neu oncogene by corosolic acid induces cell-cycle arrest and apoptosis in NCI-N87 human gastric cancer cells. Biol Pharm Bull, 33(6):931-7.


Xu YF, Ge RL, Du J, et al. (2009). Corosolic acid induces apoptosis through mitochondrial pathway and caspases activation in human cervix adenocarcinoma HeLa cells. Cancer Letters, 284(2):229-237. doi:10.1016/j.canlet.2009.04.028.