The Microbiota and Ovarian Cancer

Abstract

The cellular components of the immune system and the inflammatory milieu that it can generate is a central theme in many diseases including cancer. Immune cells can be manipulated by tumor cells to favor a pro-tumor microenvironment resulting in tumor progression. Ovarian cancer can alter its microenvironment favoring tumor growth by suppressing effector T cells as well as recruiting myeloid-derived cells, Th17 cells, γδ T cells, as well as non-immune cells such as adipose cells to aid in the generation or the propagation of the pro-inflammatory milieu. The human microbiome maintains a delicate balance between pro- and anti-inflammatory mechanisms, essential for gut homeostasis, and has critical roles in immune system development and metabolism. Alterations in the microbiome results in dysbiosis, quantitative and qualitative shifts in microbial populations, and contributes to chronic inflammation in various diseases including cancer. We highlight the role that the gut microbiota may play in cancer initiation and/or progression as well as its impact on cancer therapy. The association and interactions between the microbiome, both gut microbiota as well as infectious virus, with ovarian cancer, is reviewed here. Understanding the mechanisms by which the microbiome modulates the innate and adaptive immune response and contributes to an inflammatory milieu in cancer may offer insights into novel therapeutic targets.