Hypothesis : Bacterial induced inflammation disrupts the orderly progression of the stem cell hierarchy and has a role in the pathogenesis of breast cancer

Marwaha, A.K. and Morris, J.A. and Rigby, R.J. (2020) Hypothesis : Bacterial induced inflammation disrupts the orderly progression of the stem cell hierarchy and has a role in the pathogenesis of breast cancer. Medical Hypotheses, 136: 109530. ISSN 0306-9877

Full text not available from this repository.

Abstract

Background: The hierarchical model of stem cell genesis is based on the idea that the number of cell divisions between the zygote and fully differentiated epithelial cells is kept close to the minimum, which is log to the base 2 of the total number of cells produced in a human lifetime. The model assumes the orderly progression of stem cell divisions requires precise control at every stage in development. If the orderly progression is maintained then cancer will be rare. A prediction of the model is that if the orderly progression of the stem cell hierarchy is disturbed by trauma, ulceration or inflammation then cancer will occur. Hypothesis: Bacterial induced inflammation in breast ducts disturbs the stem cell hierarchy and is a cause of breast cancer. Evidence: Mammalian milk is not sterile. It contains a range of bacteria, derived endogenously by the entero-mammary circulation. The dominant flora consists of lactose fermenting bacteria. Pregnancy and breast feeding reduce the risk of subsequent breast cancer. The implication is that a lactose fermenting bacterial flora in breast ducts is protective. Malignant and benign breast tissue contains bacteria derived endogenously, but studies so far have not revealed a specific flora associated with malignancy. Periodontitis is associated with oral, oesophageal, colonic, pancreatic, prostatic and breast cancer. The pathogenic bacteria which cause periodontitis spread endogenously to cause inflammation at other epithelial sites. Meta-analysis of epidemiological studies shows that the consumption of yoghurt is associated with a reduction in the risk of breast cancer. Conclusion: The hypothesis, although not proven, is supported by the available evidence. Lactose fermenting bacteria protect but pathogenic bacteria which induce inflammation raise the risk of breast cancer. The consumption of yoghurt also appears to be protective.

Item Type:
Journal Article
Journal or Publication Title:
Medical Hypotheses
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/2700/2700
Subjects:
?? hierarchical stem cell modelbreast cancermammalian milk bacterial florabreastfeedingmammary duct dysbiosisperiodontitisyoghurtgeneral medicinemedicine(all) ??
ID Code:
139988
Deposited By:
Deposited On:
16 Jan 2020 14:25
Refereed?:
Yes
Published?:
Published
Last Modified:
16 Jul 2024 11:21