Journal of Genomes and Exomes

Infections may play a larger role in breast cancer than previously believed, especially if normal breast cell architecture and immune defenses have been weakened by gene mutations. Mutated genes in 289 breast cancers were compared with mutated genes in model viral and non-viral cancers. DNA sequences were obtained from publicly available data. Mutated genes in breast cancers were just as likely to be found in viral cancers as in non-viral cancers. Breast, viral, and non-viral cancers all had damage to genes encoding essential immune functions and physical barriers to cell infection. Potentially, damage to these protective genes can suppress control of cancer-associated viruses and open easier routes for infectious particles. Genes that provide protection against cancer viruses and form barriers against infection were damaged in every breast, viral, and non-viral cancer tested. Breast and other cancer cells may already harbor infections. Gaps in immunity or in infection barriers caused by distinct individual sets of mutations make cancer cells more susceptible than normal cells to infections that can exploit the cancer mutations. Other infections may be less likely because mutations have altered host proteins the other infection requires. Understanding gaps in cell defenses may enable therapy that more specifically destroys cancer cells and preserves normal cells.

Corrigendum