Microbiota and Breast Cancer.

Breast carcinogenesis and/or cancer growth and/or drug sensitivity has a multifactorial etiology-perhaps the least well-characterized aspect being that of the distant environmental influences, namely, the microbiota that inhabit humans. For the purposes of this chapter, and to keep the subject matter well defined, microbiota is defined as bacterial microbes only. In this chapter, the pathways that lead to priming of breast cancer and/or the maintenance of a malignant state and/or influences on drug sensitivity via bacterial influences will be identified and described. Specifically, major influence of bacteria found within breast tissue, skin, the oropharynx, and the gastrointestinal tract will be discussed as pertinent to published data. Finally, some preliminary conclusions of the important contributions and pathways of specific bacteria to breast carcinogenesis and/or cancer will be presented.