Title: Metformin in Cancer Prevention and Therapy: New Application of an Old Drug
Authors: Dr Asmita Jain, Dr Anindya Bhalla, Dr Sankalp Verma
DOI: https://dx.doi.org/10.18535/jmscr/v5i4.97
Abstract
Metformin, one of most widely prescribed oral anti-diabetic drug has emerged as a potential anti-cancer drug because of its potential anti-tumorigenic effects that are thought to be independent of its hypoglycaemic effects. Over the last few years, a mass of epidemiologic, outcomes and preclinical data has emerged that demonstrate the potential clinical relevance and the mechanistic basis of the anti-cancer activity of this well tolerated drug.
Several potential mechanisms have been suggested for the ability of metformin to suppress cancer growth in vitro and vivo: activation of LKB1/AMPK pathway, induction of cell cycle arrest and/or apoptosis, inhibition of protein synthesis, reduction in circulating insulin levels, inhibition of the unfolded protein response (UPR), activation of the immune system, and eradication of cancer stem cells.
There is also a growing number of evidence, mostly in the form of retrospective clinical studies that suggest that metformin may be associated with a decreased risk of developing cancer and with a better response to chemotherapy. There are currently several ongoing randomized clinical trials that incorporate metformin as an adjuvant to classic chemotherapy and aim to evaluate its potential benefits in this setting.
This review highlights basic aspects of the molecular biology of metformin and summarizes new advances in basic science as well as intriguing results from recent clinical studies.
Keywords: Metformin, cancer, molecular action, clinical evidence.
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