Review Article

Microbiome and morbid obesity increase pathogenic stimulus diversity

¹ Theodor-Billroth-Academy®, 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: 22 March 2018
Accepted: 21 November 2018

Abstract

The microbiome, the relationship between environmental factors, a high-fat diet, morbid obesity, and host response have been associated with cancer, only a small fraction of which (<10%) are genetically triggered. This nongenetic association is underpinned by a worldwide increase in morbid obesity, which is associated with both insulin resistance and chronic inflammation. The connection of the microbiome and morbid obesity is reinforced by an approximate shift of about 47% in the estimated total number of bacteria and an increase from 38,000,000,000,000 in a reference man to 56,000,000,000,000 in morbid obesity leading to a disruption of the microbial ecology within the gut. Humans contain 6,000,000,000 microbes and more than 90% of the cells of the human body are microorganisms. Changes in the microflora of the gut are associated with the polarization of ion channels by butyrate, thereby influencing cell growth. The decrease in the relative proportion of Bacteroidetes together with a change in the fermentation of carbohydrates by bacteria is observed in morbid obesity. The disruption of homeostasis of the microflora in the obese changes signaling and crosstalk of several pathways, resulting in inflammation while suppressing apoptosis. The interactions between the microbiome and morbid obesity are important to understand signaling and crosstalk in the context of the progression of the six-step sequence of carcinogenesis. This disruption of homeostasis increases remodeling of the extracellular matrix and fibrosis followed by the none-resolvable precancerous niche as the internal pathogenic stimuli continue. The chronic stress explains why under such circumstances there is a greater proclivity for normal cells to undergo the transition to cancer cells.