Cytotoxicity of Mycobacterium indicus pranii on Mia-Pa-Ca2 cells

Abstract

MIP is a cultivable, non-pathogenic organism, which shares several antigens with Mycobacterium tuberculosis and Mycobacterium leprae. It has several proposed clinical applications. However, its cytotoxic effect on pancreatic cancer has not been documented. Hence, the study was conducted to investigate MIP induced cytotoxicity on Mia-Pa-Ca2 cells. To determine the cytotoxic potential of heat killed Mycobacterium indicus pranii (MIP) on pancreatic cancer cells in vitro along with gemcitabine & 5-fluorouracil (5-FU). Mitogen-activated protein kinase (MAPK) level was also studied post MIP treatment. Cytotoxic effect of MIP, gemcitabine and 5-FU on Mia-Pa-Ca2 cells was determined. We have analyzed extent of apoptosis using flow cytometry and changes in p38 levels, c-Jun N-terminal kinases (JNK) and extracellular signal–regulated kinase (ERK) using ELISA. MIP not only exhibits cell cytotoxicity in dose dependent manner, but also enhances efficacy of gemcitabine and 5-FU when used in combination. Flow cytometry analyses reveals apoptosis of Mia-Pa-Ca2 cells post MIP treatment compared to untreated cells. MAPK pathway study using ELISA shows that p38 and JNK levels are suppressed while there is no change in ERK level. With these results we conclude that MIP is a cytotoxic agent. Cytotoxicity is exhibited by apoptosis. Combining MIP with gemcitabine and 5-FU shows synergistic effect.