member(s) of human papilloma virus (HPV) family may be responsible 4some brst cancers

[Lani]

HPV has been found to be associated /causative of cervical cancer, some vaginal/vulvar cancers, some head and neck cancers. THis study did not look at her2+ breast cancer, but the model of her2+ breast cancer they use in research in mice is virus-caused/related. Food for thought:


Cell Cycle. 2007 Jun 6;6(16) [Epub ahead of print]
E6/E7 of HPV Type 16 Promotes Cell Invasion and Metastasisof Human Breast Cancer Cells.

Yasmeen A, Bismar TA, Kandouz M, Foulkes WD, Desprez PY, Moustafa AE.
Program in Cancer Genetics, Oncology and Human Genetics Departments, McGill University, Montreal, Quebec, Canada; Montreal Center for Experimental Therapeutics in Cancer, Lady Davis Institute for Medical Research of the Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec, Canada.
Human papillomaviruses (HPVs) could be important risk factors for breast carcinogenesis and metastasis, as roughly 50% of breast cancers are positive for high-risk HPVs. To determine the role of high-risk HPVs in human breast carcinogenesis and metastasis, we examined the effect of E6/E7 of HPV type 16 in two non-invasive breast cancer cell lines, MCF7 and BT20. We report that E6/E7 of HPV type 16 induces cell invasive and metastatic abilities of MCF7 and BT20 in vitro and in vivo, respectively, in comparison with the wild type cells. This is accompanied by an upregulation of Id-1, a family member of helix-loop-helix (HLH) transcription factors, in MCF7 and BT20 cell lines which express E6/E7. Earlier studies have reported that Id-1 regulates cell invasion and metastasis of human breast cancer cells. To gauge the role of Id-1 in cell invasion and metastasis induced by E6/E7 of HPV type 16, we investigated the effect of E6/E7 in mouse normal embryonic fibroblast (NEF) and knockout Id-1 (Id-1(-/-)) cells. We establish that E6/E7 induces cell invasive ability in NEF but not Id-1(-/-) cells; moreover, we were able to inhibit the invasion ability of MCF7-E6/E7 and BT20-E6/E7 using Id-1 antisense retroviruses. Furthermore, we report that E6/E7 oncoproteins up-regulate Id-1 promoter activity in MCF7 and BT20 cells. We also found that HPV type 16 is present in all invasive and metastatic breast cancer and less frequently in in-situ breast cancer as opposed to normal mammary tissue. In parallel, we demonstrate that Id-1 overexpression is correlated with the presence of HPV type 16 in human invasive and metastatic breast cancer. These data suggest that high-risk HPV infections can induce cell invasion and metastasis in breast cancer through Id-1 regulation.
PMID: 17721085 [PubMed - as supplied by publisher]

[Hopeful]

Thanks again for a thought provoking post, Lani. It will be interesting to see, down the road, if those women who receive the HPV vaccine have lower bc rates as well as lower cervical cancer rates.

Hopeful