Bitter melon juice causes apoptotic death of human pancreatic carcinoma cells

Bitter melon juice activates cellular energy sensor AMP-activated protein kinase causing apoptotic death of human pancreatic carcinoma cells

Abstract:

Prognosis of pancreatic cancer is extremely poor, suggesting critical needs for additional drugs to improve disease outcome. In this study, we examined efficacy and associated mechanism of a novel agent bitter melon juice (BMJ) against pancreatic carcinoma cells both in culture and nude mice. BMJ anticancer efficacy was analyzed in human pancreatic carcinoma BxPC-3, MiaPaCa-2, AsPC-1 and Capan-2 cells by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide, cell death enzyme-linked immunosorbent assay and annexin/propidium iodide assays. BMJ effect on apoptosis regulators was assessed by immunoblotting. In vivo BMJ efficacy was evaluated against MiaPaCa-2 tumors in nude mice, and xenograft was analyzed for biomarkers by immunohistochemistry (IHC). Results showed that BMJ (2–5% v/v) decreases cell viability in all four pancreatic carcinoma cell lines by inducing strong apoptotic death. At molecular level, BMJ caused caspases activation, altered expression of Bcl-2 family members and cytochrome-c release into the cytosol. Additionally, BMJ decreased survivin and X-linked inhibitor of apoptosis protein but increased p21, CHOP and phosphorylated mitogen-activated protein kinases (extracellular signal-regulated kinase 1/2 and p38) levels. Importantly, BMJ activated adenosine monophosphate-activated protein kinase (AMPK), a biomarker for cellular energy status, and an AMPK inhibitor (Compound C) reversed BMJ-induced caspase-3 activation suggesting activated AMPK involvement in BMJ-induced apoptosis. In vivo, oral administration of lyophilized BMJ (5mg in 100 µl water/day/mouse) for 6 weeks inhibited MiaPaCa-2 tumor xenograft growth by 60% (P < 0.01) without noticeable toxicity in nude mice. IHC analyses of MiaPaCa-2 xenografts showed that BMJ also inhibits proliferation, induces apoptosis and activates AMPK in vivo. Overall, BMJ exerts strong anticancer efficacy against human pancreatic carcinoma cells, both in vitro and in vivo, suggesting its clinical usefulness.

 

08032013  Carcinogenesis Oxford Journals

http://carcin.oxfordjournals.org/content/early/2013/03/13/carcin.bgt081

Bitter Melon Juice Prevents Pancreatic Cancer in Mouse Models

 

 

A University of Colorado Cancer study published this week in the journal Carcinogenesis shows that bitter melon juice restricts the ability of pancreatic cancer cells to metabolize glucose, thus cutting the cells' energy source and eventually killing them.

"Three years ago researchers showed the effect of bitter melon extract on breast cancer cells only in a Petri dish. This study goes much, much farther. We used the juice -- people especially in Asian countries are already consuming it in quantity. We show that it affects the glucose metabolism pathway to restrict energy and kill pancreatic cancer cells," says Rajesh Agarwal, PhD, co-program leader of Cancer Prevention and Control at the CU Cancer Center and professor at the Skaggs School of Pharmacy and Pharmaceutical Sciences.

 

Agarwal's interest came from connecting the dots of existing research in a novel way. Diabetes tends to presage pancreatic cancer and bitter melon has been shown to effect type-II diabetes, and has been used for centuries against diabetes in the folk medicines of China and India. Following this line of thinking, Agarwal and colleagues wondered what would happen if they closed out the middle man of diabetes and directly explored the link between bitter melon and pancreatic cancer.

The result, Agarwal says, is, "Alteration in metabolic events in pancreatic cancer cells and an activation of the AMP-activated protein kinase, an enzyme that indicates low energy levels in the cells."

 

Perhaps not coincidentally, bitter melon also regulates insulin secretion by pancreatic beta cells. After studies in cell cultures, the group showed that mouse models of pancreatic cancer that were fed bitter melon juice were 60 percent less likely to develop the disease than controls.

"It's a very exciting finding," Agarwal says. "Many researchers are engineering new drugs to target cancer cells' ability to supply themselves with energy, and here we have a naturally-occurring compound that may do just that."

 The Agarwal Lab is now applying for grants that will allow them to move the study of bitter melon into further chemoprevention trials in mouse models of pancreatic cancer.

 

12032012 Science Daily

 

http://www.sciencedaily.com/releases/2013/03/130312134920.htm