Review Article

Metformin alters signaling induced crosstalk and homeostasis in the carcinogenesis paradigm “Epistemology of the origin of cancer”

¹ Theodor-Billroth-Akademie ® , Germany, USA
² INCORE, International Consortium of Research Excellence of the Theodor-Billroth-Academy ® , Germany, USA
³ Department of Surgery, Carl-Thiem-Klinikum, Cottbus, Germany
⁴ Risk-Based Decisions Inc., Sacramento, CA, USA

^* Corresponding author: b-bruecher@gmx.de

Received: 27 March 2018
Accepted: 4 March 2019

Abstract

The anti-hyperglycemic drug, Metformin, is effective in treating early stages of diabetes and has been associated with a 37% decrease in cancer incidence. While the precise mechanisms for the anti-cancer effects of Metformin remain to be elucidated, this review shows the multiplicity of its effects on interdicting signaling and crosstalk, anti-inflammatory effects and in restoring homeostasis, which, taken together, go beyond its well-known anti-hyperglycemic effect that serves as the basis for its use in type 2 diabetes. Metformin is much more than a one-trick pony. The recent discovery of several signaling pathways influenced by Metformin appears to have potential value in cancer therapy. Based on what we know at present, Metformin promotes beneficial effects attributed to its anti-inflammatory and anti-fibrotic effects largely demonstrated in vitro. Metformin activates or upregulates while it simultaneously inhibits or downregulates multiple signaling pathways of cell-cycle arrest and apoptosis accompanied by oxidative stress, which are in accordance with the 6-step sequence of carcinogenesis. Furthermore, in vivo studies in laboratory animals and in cancer patients are beginning to address the magnitude of the anti-cancer effects and delineate its anti-cancer effects. In this context, results from prior pancreatic and non-pancreatic cancer trials, which contained a significant proportion of the patient population treated with Metformin, will have to be reexamined in light of the observed anti-cancerous effects to gain additional insights. The detailed exploration of Metformin in the context of the “Disruption of signaling homeostasis induced crosstalk in the carcinogenesis paradigm Epistemology of the origin of cancer” can provide helpful insights into the anti-proliferative mechanisms and could play a relevant role in anti-cancer therapy in the future.