Resveratrol induces apoptosis in pancreatic cancer cells.

BACKGROUND: Pancreatic cancer is one of the most lethal human cancers with a very low survival rate of 5 years. Conventional cancer treatments including surgery, radiation, chemotherapy or combinations of these show little effect on this disease. Several proteins have been proved critical to the development and the progression of pancreatic cancer. The aim of this study was to investigate the effect of resveratrol on apoptosis in pancreatic cancer cells. METHODS: Several pancreatic cancer cell lines were screened by resveratrol, and its toxicity was tested by normal pancreatic cells. Western blotting was then performed to analyze the molecular mechanism of resveratrol induced apoptosis of pancreatic cancer cell lines. RESULTS: In the screened pancreatic cancer cell lines, capan-2 and colo357 showed high sensitivity to resveratrol induced apoptosis. Resveratrol exhibited insignificant toxicity to normal pancreatic cells. In resveratrol sensitive cells, capan-2 and colo357, the activation of caspase-3 was detected and showed significant caspase-3 activation upon resveratrol treatment; p53 and p21 were also detected up-regulated upon resveratrol treatment. CONCLUSION: Resveratrol provides a promising anti-tumor strategy to fight against pancreatic cancer.

[Production and identification of monoclonal antibody against human S100A4.].

AIM: To prepare specific monoclonal antibody against human S100A4 protein and establish a reliable method to detect S100A4 protein in tumor specimens. METHODS: A standard hybridoma method was used to generate monoclonoal antibodies against recombinant human S100A4. ELISA, Western blot and immunohistochemistry were used to validate this antibody and the antibody is used to examine specimens of human breast and colon cancers. RESULTS: One hybridoma cell line which secreted monoclonal antibody specifically against recombinant human S100A4 protein was obtained and named as D101. The monoclonal antibody is shown to be more specific for S100A4 protein than the polyclonal antibody, at least in Western blot. The monoclonal antibody is suitable for detecting the expression of S100A4 in specimens from human tissues and gave results consistent with those of a commercially available polyclonal antibody in a small group of breast and colorectal carcinomas. CONCLUSION: The monoclonal antibody is specific for S100A4 and can be produced on a large scale; therefore it will be more reproducible for future clinical applications.

hTERT-targeted E. coli purine nucleoside phosphorylase gene/6-methylpurine deoxyribose therapy for pancreatic cancer.

BACKGROUND: Pancreatic cancer is one of the most common tumors and has a 5-year survival for all stages of less than 5%. Most patients with pancreatic cancer are diagnosed at an advanced stage and therefore are not candidates for surgical resection. In recent years, investigation into alternative treatment strategies for this aggressive disease has led to advances in the field of gene therapy for pancreatic cancer. E. coli purine nucleoside phosphorylase/6-methylpurine deoxyribose (ePNP/MePdR) is a suicide gene/prodrug system where PNP enzyme cleaves nontoxic MePdR into cytotoxic membrane-permeable compounds 6-methylpurine (MeP) with high bystander activity. hTERT is expressed in cell lines and tissues for telomerase activity. In this study we examined the efficacy of ePNP under the control of hTERT promoter sequences and assessed the selective killing effects of the ePNP/prodrug MePdR system on pancreatic tumors. METHODS: Recombinant pET-PNP was established. The protein of E. coli PNPase was expressed and an antibody to E. coli PNPase was prepared. Transcriptional activities of hTERT promoter sequences were analyzed using a luciferase reporter gene. A recombinant phTERT-ePNP vector was constructed. The ePNP/MePdR system affects SW1990 human pancreatic cancer cell lines in vitro. RESULTS: The hTERT promoter had high transcriptional activity and conferred specificity on cancer cell lines. The antibody to E. coli PNPase was demonstrated to be specific for the ePNP protein. The MePdR treatment induced a high in vitro cytotoxicity on the sole hTERT-ePNP-producing cell lines and affected SW1990 cells in a dose-dependent manner. CONCLUSIONS: The hTERT promoter control of the ePNP/MePdR system can provide a beneficial anti-tumor treatment in pancreatic cancer cell lines including a good bystander killing effect.