Category Archives: Induces cell-cycle arrest

A549, Akt, apoptosis, BAX, Bcl-2, BEL-7402, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, ERK1, Gentian waltonii, Induces cell-cycle arrest, Lung cancer, S

Waltonitone

Cancer: Hepatocellular carcinoma, lung

Action: Induces cell-cycle arrest

Hepatocellular Carcinoma

Waltonitone, a new ursane-type pentacyclic triterpene isolated from Gentian waltonii Burkill, significantly inhibited human hepatocellular carcinoma BEL-7402 cells growth. Apoptosis induced by waltonitone was characterized by AO/EB staining and flow cytometric analysis. Apoptosis microarray assay results showed BCL-2 family genes might especially play an important role in waltonitone-induced apoptosis.

These studies demonstrated that waltonitone might inhibit hepatocellular carcinoma cell growth and induce apoptosis in vitro and in vivo (Zhang et al., 2009a).

Adenocarcinomic Lung Cancer

Natural compounds are a great source of cancer chemotherapeutic agents. An investigation by Zhang et al. (2012) indicates that waltonitone (WT), a triterpene extracted from medicinal plants, inhibits the proliferation of A549 cells in a concentration- and time-dependent manner.

Furthermore, the treatment of A549 cells with waltonitone altered the expression of miRNAs. It was found that 27 miRNAs were differentially expressed in waltonitone-treated cells, of which 8 miRNAs target genes related to cell proliferation and apoptosis.

In summary, results demonstrate that waltonitone has a significant inhibitory effect on the proliferation of A549 cells. It is possible that up-regulation of Bax/Bcl-2 and regulation of expression of specific miRNAs play a role in inhibition of proliferation and induction of apoptosis in waltonitone-treated cells. Waltonitone can be applied to lung carcinoma as a chemotherapeutic candidate.

Hepatocellular Carcinoma

WT could inhibit the BEL-7402 cells growth, induce the S-phase cell-cycle arrest, and activate Akt and ERK1/2 phosporylation. Moreover, the cell growth inhibition and S-phase cell-cycle arrest induction of WT on BEL-7402 cells could be blocked by Akt and ERK1/2 inhibitors.

WT induces cell-cycle arrest and inhibits the cell growth on BEL-7402 cells by modulating Akt and ERK1/2 phosphorylation (Zhang et al., 2009b).

References

Zhang Y, Zhang GB, Xu XM, et al. (2012). Suppression of growth of A549 lung cancer cells by waltonitone and its mechanisms of action. Oncol Rep, 28(3):1029-35. doi: 10.3892/or.2012.1869.


Zhang Z, Wang S, Qiu H, Duan C, Ding K, Wang Z (a). (2009). Waltonitone induces human hepatocellular carcinoma cells apoptosis in vitro and in vivo. Cancer Lett, 286(2):223-31. doi: 10.1016/j.canlet.2009.05.023.


Zhang Z, Duan C, Ding K, Wang Z (b). (2009). WT inhibit human hepatocellular carcinoma BEL-7402 cells growth by modulating Akt and ERK1/2 phosphorylation. Zhongguo Zhong Yao Za Zhi, 34(24):3277-80.

AIF, anti-apoptotic, apoptosis, apoptosis-inducing, Apoptotic, BAX, Bcl-2, Bcl-xL, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Colon Cancer or Colorectal cancer, ER, Esophageal cancer, G0/G1, G1, GADD153, Gynostemma pentaphyllum, Induces cell-cycle arrest, inhibits cell proliferation and migration, Oral cancer, Pro-apoptotic, ROS

Gypenosides

Cancer: Leukemia, colorectal., oral., esophageal

Action: Apoptosis,inhibits cell proliferation and migration

Gypenosides (Gyp), found in Gynostemma pentaphyllum Makino [(Thunb) Makino], have been used as folk medicine for centuries and have exhibited diverse pharmacological effects, including anti-leukemia effects in vitro and in vivo.

Gyp have been used to examine effects on cell viability, cell-cycle, and induction of apoptosis in vitro. They were administered in the diet to mice injected with WEHI-3 cells in vivo. Gyp inhibited the growth of WEHI-3 cells. These effects were associated with the induction of G0/G1 arrest, morphological changes, DNA fragmentation, and increased sub-G1 phase. Gyp promoted the production of reactive oxygen species, increased Ca2+ levels, and induced the depolarization of the mitochondrial membrane potential.

The effects of Gyp were dose- and time-dependent. Moreover, Gyp increased levels of the pro-apoptotic protein Bax, reduced levels of the anti-apoptotic proteins Bcl-2, and stimulated release of cytochrome c, AIF (apoptosis-inducing factor), and Endo G (endonuclease G) from mitochondria. The levels of GADD153, GRP78, ATF6-α, and ATF4-α were increased by Gyp, resulting in ER (endoplasmic reticular) stress in WEHI-3 cells. Oral consumption of Gyp increased the survival rate of mice injected with WEHI-3 cells used as a mouse model of leukemia.

Results of these experiments provide new information on understanding mechanisms of Gyp-induced effects on cell-cycle arrest and apoptosis in vitro and in an in vivo animal model (Hsu et al., 2011).

Inhibits Cell Proliferation and Migration

Results indicated that Gypenosides (Gyp) inhibited cell proliferation and migration in SW620 and Eca-109 cells in dose- and time-dependent manner. Gyp elevated intracellular ROS level, decreased the Δψ m, and induced apoptotic morphology such as cell shrinkage and chromatin condensation, suggesting oxidative stress and mitochondria-dependent cell apoptosis that might be involved in Gyp-induced cell viability loss in SW620 and Eca-109 cells. The findings indicate Gyp may have valuable application in clinical colon cancer and esophageal cancer treatments (Yan et al., 2013).

Gyp-induced cell death occurs through caspase-dependent and caspase-independent apoptotic signaling pathways, and the compound reduced tumor size in a xenograft nu/nu mouse model of oral cancer.

Gyp induced morphological changes, decreased the percentage of viable cells, caused G0/G1 phase arrest, and triggered apoptotic cell death in SAS cells. Cell-cycle arrest induced by Gyp was associated with apoptosis. The production of ROS, increased intracellular Ca(2+) levels, and the depolarization of ΔΨ(m) were observed. Gyp increased levels of the pro-apoptotic protein Bax but inhibited the levels of the anti-apoptotic proteins Bcl-2 and Bcl-xl. Gyp also stimulated the release of cytochrome c and Endo G. Translocation of GADD153 to the nucleus was stimulated by Gyp. Gyp in vivo attenuated the size and volume of solid tumors in a murine xenograft model of oral cancer (Lu et al., 2012).

Cell-cycle Arrest

Lin et al. (2011) have shown that gypenosides (Gyp) induced cell-cycle arrest and apoptosis in many human cancer cell lines. In the present study the effects of Gyp on cell morphological changes and viability, cell-cycle arrest and induction of apoptosis in vitro and effects on Gyp in an in vivo murine xenograft model were demonstrated. Results indicated that Gyp induced morphological changes, decreased cell viability, induced G0/G1 arrest, DNA fragmentation and apoptosis (sub-G1 phase) in HL-60 cells. Gyp increased reactive oxygen species production and Ca(2+) levels but reduced mitochondrial membrane potential in a dose- and time-dependent manner.

Oral consumption of Gyp reduced tumor size of HL-60 cell xenograft mode mice in vivo. These results provide new information on understanding mechanisms by which Gyp induces cell-cycle arrest and apoptosis in vitro and in vivo (Lin et al., 2011).

References

Hsu HY, Yang JS, Lu KW, et al. (2011). An Experimental Study on the Anti-leukemia Effects of Gypenosides In Vitro and In Vivo. Integr Cancer Ther, 10(1):101-12. doi: 10.1177/1534735410377198.


Lin JJ, Hsu HY, Yang JS, et al. (2011). Molecular evidence of anti-leukemia activity of gypenosides on human myeloid leukemia HL-60 cells in vitro and in vivo using a HL-60 cells murine xenograft model. Phytomedicine,18(12):1075-85. doi: 10.1016/j.phymed.2011.03.009.


Lu KW, Chen JC, Lai TY, et al. (2012). Gypenosides suppress growth of human oral cancer SAS cells in vitro and in a murine xenograft model: the role of apoptosis mediated by caspase-dependent and caspase-independent pathways. Integr Cancer Ther, 11(2):129-40. doi: 10.1177/1534735411403306.


Yan H, Wang X, Wang Y, Wang P, Xiao Y. (2013). Antiproliferation and anti-migration induced by gypenosides in human colon cancer SW620 and esophageal cancer Eca-109 cells. Hum Exp Toxicol.

Akt, Anti-cancer, anti-inflammatory, anti-proliferative, apoptosis, Apoptotic, Bcl-2, Breast cancer, cell-cycle arrest, Chapter 8 Injectables and Cancer Research, Colon Cancer or Colorectal cancer, COX-2, G1, induces apoptosis, Induces cell-cycle arrest, inflammation, Lung cancer, MCP-1, Melanoma, Nigella sativa, Osteosarcoma, p21, p53, Pro-apoptotic, Sarcoma, TNF

Thymoquinone

Cancer: Osteosarcoma, pancreatic, colorectal., lung, liver, melanoma, breast

Action: Anti-inflammatory

For centuries, the black seed (Nigella sativa (L.)) herb and oil have been used in Asia, Middle East and Africa to promote health and fight disease. Thymoquinone (TQ) is the major phytochemical constituent of Nigella sativa (L.) oil extract. Phytochemical compounds are emerging as a new generation of anti-cancer agents with limited toxicity in cancer patients.

Osteosarcoma

The anti-proliferative and pro-apoptotic effects of TQ were evaluated in two human osteosarcoma cell lines with different p53 mutation status. TQ decreased cell survival dose-dependently and, more significantly, in p53-null MG63 cells (IC(50) = 17 muM) than in p53-mutant MNNG/HOS cells (IC(50) = 38 muM). Cell viability was reduced more selectively in MG63 tumor cells than in normal human osteoblasts.

It was therefore suggested that the resistance of MNNG/HOS cells to drug-induced apoptosis is caused by the up-regulation of p21(WAF1) by the mutant p53 (transcriptional activity was shown by p53 siRNA treatment) which induces cell-cycle arrest and allows repair of DNA damage.

Collectively, these findings show that TQ induces p53-independent apoptosis in human osteosarcoma cells. As the loss of p53 function is frequently observed in osteosarcoma patients, these data suggest the potential clinical usefulness of TQ for the treatment of these malignancies (Roepke et al., 2007).

Pancreatic Ductal Adenocarcinoma

Inflammation has been identified as a significant factor in the development of solid tumor malignancies. It has recently been shown that thymoquinone (Tq) induces apoptosis and inhibited proliferation in PDA cells. The effect of Tq on the expression of different pro-inflammatory cytokines and chemokines was analyzed by real-time polymerase chain reaction (PCR). Tq dose- and time-dependently significantly reduced PDA cell synthesis of MCP-1, TNF-alpha, interleukin (IL)-1beta and Cox-2. Tq also inhibited the constitutive and TNF-alpha-mediated activation of NF-kappaB in PDA cells and reduced the transport of NF-kappaB from the cytosol to the nucleus. Our data demonstrate previously undescribed anti-inflammatory activities of Tq in PDA cells, which are paralleled by inhibition of NF-kappaB. Tq as a novel inhibitor of pro-inflammatory pathways provides a promising strategy that combines anti-inflammatory and pro-apoptotic modes of action (Chehl et al., 2009).

Lung cancer, Hepatoma, Melanoma, Colon Cancer, Breast Cancer

The potential impact of thymoquinone (TQ) was investigated on the survival., invasion of cancer cells in vitro, and tumor growth in vivo. Exposure of cells derived from lung (LNM35), liver (HepG2), colon (HT29), melanoma (MDA-MB-435), and breast (MDA-MB-231 and MCF-7) tumors to increasing TQ concentrations resulted in a significant inhibition of viability through the inhibition of Akt phosphorylation leading to DNA damage and activation of the mitochondrial-signaling pro-apoptotic pathway. Administration of TQ (10 mg/kg/i.p.) for 18 days inhibited the LNM35 tumor growth by 39% (P < 0.05). Tumor growth inhibition was associated with significant increase in the activated caspase-3. In this context, it has been demonstrated that TQ treatment resulted in a significant inhibition of HDAC2 proteins. In view of the available experimental findings, it is contended that thymoquinone and/or its analogues may have clinical potential as an anti-cancer agent alone or in combination with chemotherapeutic drugs such as cisplatin (Attoub et al., 2012).

Colon Cancer

It was reported that TQ inhibits the growth of colon cancer cells which was correlated with G1 phase arrest of the cell-cycle. Furthermore, TUNEL staining and flow cytometry analysis indicate that TQ triggers apoptosis in a dose- and time-dependent manner. These results indicate that TQ is anti-neoplastic and pro-apoptotic against colon cancer cell line HCT116. The apoptotic effects of TQ are modulated by Bcl-2 protein and are linked to and dependent on p53. Our data support the potential for using the agent TQ for the treatment of colon cancer (Gali-Muhtasib et al., 2004).

References

Attoub S, Sperandio O, Raza H, et al. (2012). Thymoquinone as an anti-cancer agent: evidence from inhibition of cancer cells viability and invasion in vitro and tumor growth in vivo. Fundam Clin Pharmacol, 27(5):557-569. doi: 10.1111/j.1472-8206.2012.01056.x


Chehl N, Chipitsyna G, Gong Q, Yeo CJ, Arafat HA. (2009). Anti-inflammatory effects of the Nigella sativa seed extract, thymoquinone, in pancreatic cancer cells. HPB (Oxford), 11(5):373-81. doi: 10.1111/j.1477-2574.2009.00059.x.


Gali-Muhtasib H, Diab-Assaf M, Boltze C, et al. (2004). Thymoquinone extracted from black seed triggers apoptotic cell death in human colorectal cancer cells via a p53-dependent mechanism. Int J Oncol, 25(4):857-66


Roepke M, Diestel A, Bajbouj K, et al. (2007). Lack of p53 augments thymoquinone-induced apoptosis and caspase activation in human osteosarcoma cells. Cancer Biol Ther, 6(2):160-9.

A431, Akt, Anti-cancer, anti-inflammatory, anti-proliferative, apoptosis, Apoptotic, Bcl-2, Breast cancer, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Colon Cancer or Colorectal cancer, COX-2, G1, HCT-116, Hep2, HepG2, HT29, induces apoptosis, Induces cell-cycle arrest, inflammation, inhibits proliferation, Liver cancer, LNM35, MCP-1, MDA-MB-231 and MCF-7, MDA-MB-435, Melanoma, Nigella sativa, Osteosarcoma, p21, p53, Pancreatic cancer, Pro-apoptotic, Saos-2, Sarcoma, TNF

Thymoquinone

Cancer: Osteosarcoma, pancreatic, colorectal., lung, liver, melanoma, breast

Action: Anti-inflammatory

For centuries, the black seed (Nigella sativa (L.)) herb and oil have been used in Asia, Middle East and Africa to promote health and fight disease. Thymoquinone (TQ) is the major phytochemical constituent of Nigella sativa (L.) oil extract. Phytochemical compounds are emerging as a new generation of anti-cancer agents with limited toxicity in cancer patients.

Osteosarcoma

The anti-proliferative and pro-apoptotic effects of TQ were evaluated in two human osteosarcoma cell lines with different p53 mutation status. TQ decreased cell survival dose-dependently and, more significantly, in p53-null MG63 cells (IC(50) = 17 muM) than in p53-mutant MNNG/HOS cells (IC(50) = 38 muM). Cell viability was reduced more selectively in MG63 tumor cells than in normal human osteoblasts.

It was therefore suggested that the resistance of MNNG/HOS cells to drug-induced apoptosis is caused by the up-regulation of p21(WAF1) by the mutant p53 (transcriptional activity was shown by p53 siRNA treatment) which induces cell-cycle arrest and allows repair of DNA damage.

Collectively, these findings show that TQ induces p53-independent apoptosis in human osteosarcoma cells. As the loss of p53 function is frequently observed in osteosarcoma patients, these data suggest the potential clinical usefulness of TQ for the treatment of these malignancies (Roepke et al., 2007).

Pancreatic Ductal Adenocarcinoma

Inflammation has been identified as a significant factor in the development of solid tumor malignancies. It has recently been shown that thymoquinone (Tq) induces apoptosis and inhibited proliferation in PDA cells. The effect of Tq on the expression of different pro-inflammatory cytokines and chemokines was analyzed by real-time polymerase chain reaction (PCR). Tq dose- and time-dependently significantly reduced PDA cell synthesis of MCP-1, TNF-alpha, interleukin (IL)-1beta and Cox-2. Tq also inhibited the constitutive and TNF-alpha-mediated activation of NF-kappaB in PDA cells and reduced the transport of NF-kappaB from the cytosol to the nucleus. Our data demonstrate previously undescribed anti-inflammatory activities of Tq in PDA cells, which are paralleled by inhibition of NF-kappaB. Tq as a novel inhibitor of pro-inflammatory pathways provides a promising strategy that combines anti-inflammatory and pro-apoptotic modes of action (Chehl et al., 2009).

Lung cancer, Hepatoma, Melanoma, Colon Cancer, Breast Cancer

The potential impact of thymoquinone (TQ) was investigated on the survival., invasion of cancer cells in vitro, and tumor growth in vivo. Exposure of cells derived from lung (LNM35), liver (HepG2), colon (HT29), melanoma (MDA-MB-435), and breast (MDA-MB-231 and MCF-7) tumors to increasing TQ concentrations resulted in a significant inhibition of viability through the inhibition of Akt phosphorylation leading to DNA damage and activation of the mitochondrial-signaling pro-apoptotic pathway. Administration of TQ (10 mg/kg/i.p.) for 18 days inhibited the LNM35 tumor growth by 39% (P < 0.05). Tumor growth inhibition was associated with significant increase in the activated caspase-3. In this context, it has been demonstrated that TQ treatment resulted in a significant inhibition of HDAC2 proteins. In view of the available experimental findings, it is contended that thymoquinone and/or its analogues may have clinical potential as an anti-cancer agent alone or in combination with chemotherapeutic drugs such as cisplatin (Attoub et al., 2012).

Colon Cancer

It was reported that TQ inhibits the growth of colon cancer cells which was correlated with G1 phase arrest of the cell-cycle. Furthermore, TUNEL staining and flow cytometry analysis indicate that TQ triggers apoptosis in a dose- and time-dependent manner. These results indicate that TQ is anti-neoplastic and pro-apoptotic against colon cancer cell line HCT116. The apoptotic effects of TQ are modulated by Bcl-2 protein and are linked to and dependent on p53. Our data support the potential for using the agent TQ for the treatment of colon cancer (Gali-Muhtasib et al., 2004).

References

Attoub S, Sperandio O, Raza H, et al. (2012). Thymoquinone as an anti-cancer agent: evidence from inhibition of cancer cells viability and invasion in vitro and tumor growth in vivo. Fundam Clin Pharmacol, 27(5):557-569. doi: 10.1111/j.1472-8206.2012.01056.x


Chehl N, Chipitsyna G, Gong Q, Yeo CJ, Arafat HA. (2009). Anti-inflammatory effects of the Nigella sativa seed extract, thymoquinone, in pancreatic cancer cells. HPB (Oxford), 11(5):373-81. doi: 10.1111/j.1477-2574.2009.00059.x.


Gali-Muhtasib H, Diab-Assaf M, Boltze C, et al. (2004). Thymoquinone extracted from black seed triggers apoptotic cell death in human colorectal cancer cells via a p53-dependent mechanism. Int J Oncol, 25(4):857-66


Roepke M, Diestel A, Bajbouj K, et al. (2007). Lack of p53 augments thymoquinone-induced apoptosis and caspase activation in human osteosarcoma cells. Cancer Biol Ther, 6(2):160-9.

angiogenesis, Anti-angiogenesis, Anti-angiogenic, anti-tumor, apoptosis, Bladder cancer, Breast cancer, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, chemo-preventive, Cip1/p21, Colon Cancer or Colorectal cancer, EGFR, EMT, epidermal growth factor receptor, ERK, ERK1, Fet, Geo, and HCT116, G1, HL-60, HT-29, Induces cell-cycle arrest, iNOS, Lung cancer, metastasis, Nitric Oxide, p21, PKC, S, Silybum marianum, STAT, STAT3, Thyroid cancer, TNF

Silibinin

Cancer:
Lung, leukemia, colorectal, thyroid, breast, bladder

Action: Anti-angiogenesis, EMT, cell-cycle arrest

Cell-cycle Arrest, Colon Cancer

Silibinin, an active constituent of milk thistle (Silybum marianum [(L.) Gaertn.]), has been reported to inhibit proliferation and induce cell-cycle arrest of human colon cancer cells, Fet, Geo, and HCT116 (Hogan et al., 2007). Silibinin Up-regulates the expression of cyclin-dependent kinase inhibitors and induces cell-cycle arrest and apoptosis in human colon carcinoma HT-29 cells (Agarwal et al., 2003). Also in HT-29 cells, treatment with beta-escin, a principal component of horse chestnut, tinduces growth arrest at the G1-S phase together with an induction of Cip1/p21 and an associated reduction in the phosphorylation of retinoblastoma protein (Patlolla et al., 2006).

Lung Cancer

Silibinin also has anti-angiogenic effects on lung adenocarcinomas in vitro, as it strongly decreased both tumor number and tumor size (an anti-tumor effect that correlates with reduced anti-angiogenic activity) (Tyagi et al., 2009). Further, silibinin inhibits mouse lung tumorigenesis in vivo, in part by targeting tumor microenvironment. Tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) can be pro- or anti-tumorigenic, but in lung cancer cell lines they induce pro-inflammatory enzymes cyclooxygenase 2 (COX2) and inducible nitric oxide synthase (iNOS). Accordingly, the mechanism of silibinin action was examined on TNF-α + IFN-γ (hereafter referred as cytokine mixture) elicited signaling in tumor-derived mouse lung epithelial LM2 cells.

Both signal transducers and activators of the transcription (STAT)3 (tyr705 and ser727) and STAT1 (tyr701) were activated within 15 min of cytokine mixture exposure, while STAT1 (ser727) activated after 3 h. Cytokine mixture also activated Erk1/2 and caused an increase in both COX2 and iNOS levels. Pre-treatment of cells with a MEK, NF-κB, and/or epidermal growth factor receptor (EGFR) inhibitor inhibited cytokine mixture-induced activation of Erk1/2, NF-κB, or EGFR, respectively, and strongly decreased phosphorylation of STAT3 and STAT1 and expression of COX2 and iNOS.

Together, the results show that STAT3 and STAT1 could be valuable chemo-preventive and therapeutic targets within the lung tumor microenvironment in addition to being targets within the tumor itself, and that silibinin inhibit their activation as a plausible mechanism of its efficacy against lung cancer (Tyagi et al., 2011).

Leukemia

Silibinin also affects cellular differentiation in the human promyelocytic leukemia HL-60 cell culture system. Treatment of HL-60 cells with silibinin inhibited cellular proliferation and induced cellular differentiation in a dose-dependent manner.

Silibinin enhanced protein kinase C (PKC) activity and increased protein levels of both PKCα and PKCβ in 1,25-(OH)2D3-treated HL-60 cells. PKC and extracellular signal-regulated kinase (ERK) inhibitors significantly inhibited HL-60 cell differentiation induced by silibinin alone or in combination with 1,25-(OH)2D3, indicating that PKC and ERK may be involved in silibinin-induced HL-60 cell differentiation (Kang et al., 2001).

Thyroid Cancer, Breast Cancer

Silibinin inhibits TPA-induced cell migration and MMP-9 expression in thyroid and breast cancer cells. Matrix metalloproteinases (MMPs) play an important role in cancer metastasis, cell migration and invasion. The effects of silibinin were investigated on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell migration and MMP-9 expression in thyroid and breast cancer cells. These results revealed that the levels of MMP-9 mRNA and protein expression were significantly increased by TPA but not MMP-2 in TPC-1 and MCF7 cells.

TPA-induced phosphorylation of MEK and ERK was also inhibited by silibinin. Taken together, these results suggest that silibinin suppresses TPA-induced cell migration and MMP-9 expression through the MEK/ERK-dependent pathway in thyroid and breast cancer cells (Oh et al., 2013).

Bladder Cancer

Silibinin induced apoptosis and inhibited proliferation of bladder cancer cells and metastasis. In the present study, Wu et al. (2013) utilized a novel highly metastatic T24-L cell model, and found that silibinin treatment not only resulted in the suppression of cell migration and invasion in vitro, but also decreased bladder cancer lung metastasis and prolonged animal survival in vivo. Inactivation of β-catenin/ZEB1 signaling by silibinin leads to dual-block of EMT and stemness.

Lung Cancer, EMT

Silibinin formulation might facilitate the design of clinical trials to test the administration of silibinin meglumine-containing injections, granules, or beverages in combination with EGFR TKIs in patients with EGFR-mutated NSCLC. Silibinin meglumine notably decreased the overall volumes of NSCLC tumors as efficiently as did the EGFR tyrosine kinase inhibitor (TKI) gefitinib. Concurrent treatment with silibinin meglumine impeded the regrowth of gefitinib-unresponsive tumors, resulting in drastic tumor growth prevention.

Because the epithelial-to-mesenchymal transition (EMT) is required by a multiplicity of mechanisms of resistance to EGFR TKIs, we evaluated the ability of silibinin meglumine to impede the EMT in vitro and in vivo. Silibinin-meglumine efficiently prevented the loss of markers associated with a polarized epithelial phenotype as well as the de novo synthesis of proteins associated with the mesenchymal morphology of transitioning cells (Cuf` et al., 2013).

Breast cancer

Myeloid-derived suppressor cells (MDSC)s increase in blood and accumulate in the tumor microenvironment of tumor-bearing animals, contributing to immune suppression in cancer. Silibinin, a natural flavonoid from the seeds of milk thistle, has been developed as an anti-inflammatory agent and supportive care agent to reduce the toxicity of cancer chemotherapy. The goals of this study were to evaluate the effect of silibinin on MDSCs in tumor-bearing mice and antitumor activity of silibinin in a mouse model of breast cancer. 4T1 luciferase-transfected mammary carcinoma cells were injected into in the mammary fat pad female BALB/c mice, and female CB17-Prkdc Scid/J mice. Silibinin treatment started on day 4 or day 14 after tumor inoculation continued every other day.

Tumor growth was monitored by bioluminescent imaging (BLI) measuring total photon flux. Flow cytometry measured total leukocytes, CD11b+ Gr-1+ MDSC, and T cells in the blood and tumors of tumor-bearing mice. The effects of silibinin on 4T1 cell viability in vitro were measured by BLI. Treatment with silibinin increased overall survival in mice harboring tumors derived from the 4T1-luciferase breast cancer cell line, and reduced tumor volumes and numbers of CD11b+Gr-1+ MDSCs in the blood and tumor, and increased the content of T cells in the tumor microenvironment.

Silibinin failed to inhibit tumor growth in immunocompromised severe combined immunodeficiency mice, supporting the hypothesis that anticancer effect of silibinin is immune-mediated. The antitumor activity of silibinin requires an intact host immune system and is associated with decreased accumulation of blood and tumor-associated MDSCs.

References

 

Agarwal C, Singh RP, Dhanalakshmi S, et al. (2003). Silibinin Up-regulates the expression of cyclin-dependent kinase inhibitors and causes cell-cycle arrest and apoptosis in human colon carcinoma HT-29 cells. Oncogene, 22:8271–8282.

 

Cufí S, Bonavia R, Vazquez-Martin A, Corominas-Faja B, et al. (2013). Silibinin meglumine, a water-soluble form of milk thistle silymarin, is an orally active anti-cancer agent that impedes the epithelial-to-mesenchymal transition (EMT) in EGFR-mutant non-small-cell lung carcinoma cells. Food Chem Toxicol, 60:360-8. doi: 10.1016/j.fct.2013.07.063.

Hogan FS, Krishnegowda NK, Mikhailova M, Kahlenberg MS. (2007). Flavonoid, silibinin, inhibits proliferation and promotes cell-cycle arrest of human colon cancer. J Surg Res, 143:58–65.

Kang SN, Lee MH, Kim KM, Cho D, Kim TS. (2001). Induction of human promyelocytic leukemia HL-60 cell differentiation into monocytes by silibinin: involvement of protein kinase C. Biochemical Pharmacology, 61(12):1487–1495

Oh SJ, Jung SP, Han J, et al. (2013). Silibinin inhibits TPA-induced cell migration and MMP-9 expression in thyroid and breast cancer cells. Oncol Rep, 29(4):1343-8. doi: 10.3892/or.2013.2252.

Patlolla JM, Raju J, Swamy MV, Rao CV. (2006). Beta-escin inhibits colonic aberrant crypt foci formation in rats and regulates the Cell-cycle growth by inducing p21(waf1/cip1) in colon cancer cells. Mol Cancer Ther, 5:1459–1466.

Tyagi A, Singh RP, Ramasamy K, et al. (2009). Growth Inhibition and Regression of Lung Tumors by Silibinin: Modulation of Angiogenesis by Macrophage-Associated Cytokines and Nuclear Factor-κ B and Signal Transducers and Activators of Transcription 3. Cancer Prev Res, 2(1):74-83

Tyagi A, Agarwal C, Dwyer-Nield LD, et al. (2011). Silibinin modulates TNF‐α and IFN ‐γ mediated signaling to regulate COX2 and iNOS expression in tumorigenic mouse lung epithelial LM2 cells. Molecular Carcinogenesis. doi: 10.1002/mc.20851.

Wu K, Ning Z, Zeng J, et al. (2013). Silibinin inhibits β -catenin/ZEB1 signaling and suppresses bladder cancer metastasis via dual-blocking epithelial-mesenchymal transition and stemness. Cell Signal, 25(12):2625-2633. doi: 10.1016/j.cellsig.2013.08.028.

Forghani P, Khorramizadeh MR & Waller EK. (2014) Silibinin inhibits accumulation of myeloid-derived suppressor cells and tumor growth of murine breast cancer. Cancer Medicine. Volume 3, Issue 2, pages 215–224, April 2014 DOI: 10.1002/cam4.186