In vitro evaluation of the combined treatment of metformin and PLGA nanoparticle with methotrexate in pancreatic ductal adenocarcinoma cells.
apoptosis; caspase-3; bcl-2; cell culture
Pancreatic ductal adenocarcinoma (PDAC) accounts for 90% of malignant pancreatic tumors. Generally, the diagnosis is made at an advanced stage or in metastasis, making surgical treatment impossible. Overall survival within 5 years is only 7% of cases. One of the major risk factors for pancreatic cancer is type 2 diabetes mellitus, in addition to smoking and obesity. Metformin is an oral antiglycemic agent widely used in the treatment of diabetes mellitus. Recently, metformin has been reported with anti-tumor activity. The aim of the present study is the in vitro evaluation of the anti-apoptotic effect of the combination of metformin and nanoparticle of PLGA associated methotrexate, a standard chemotherapeutic used in anti-neoplastic treatment, but also used as anti-inflammatory in diseases such as rheumatoid arthritis (RA). The combination of metformin and PLGA-MTX nanoparticle was performed with pancreatic ductal adenocarcinoma cells, PANC-1. A pharmacological screening was performed from the viability test based on the use of resazurin to define the drug combination doses. Afterwards, flow cytometry was used to evaluate the induction of apoptosis by the combination of metformin and PLGA-MTX nanoparticle. Finally, immunofluorescence evaluated the expression of bcl-2 and caspase-3. The results show that the combination of drugs was efficient in inducing apoptosis in PANC-1 tumor cells. In addition, treatments showed reduction of the anti-apoptotic protein bcl-2 and increase of the pro-apoptotic protein caspase-3.