Is Breast Cancer Caused By MMTV Contagious?

Posted on Sat, 2 Jun 2012

Question: Hello Im sorry if my question is a little strange and abstract. I hope you can help me. I recently found that breast cancer could be caused by a virus (mmtv) and i hope you can tell me whether it is contagious and if yes how?
my mother has cancer and we share all kinds of utensils. thank you!

Answered by Dr. Indranil Ghosh (1 hour later)

Hello XXXXXXX

Thanks for the query.

I understand your concern, presumably after reading an article on MMTV (Mouse mammary tumor virus). However, though gene sequences of MMTV have been found in human breast and other cancers, its causality is not yet proven. The human-to-human transmission of MMTV causing breast cancer is even more hypothetical at this point. It is under research.

Please go through the following excerpts from recent scientific papers -

"Mouse mammary tumor virus (MMTV) is a hormonally regulated, oncogenic virus of mice. MMTV-like virus DNA has previously been detected in human breast cancers, liver disease, and liver cancers. It is hypothesized that local hormonal effects might be of primary importance in determining MMTV-like virus detection in human tumors. Therefore, unlike the mouse model, the detection of MMTV-like env sequences in human cancers in addition to breast indicates that MMTV-like viral expression is not breast cancer-specific and may relate to hormone-dependent viral expression." (Ref: J Med Virol 2010)

"Mouse mammary tumor virus (MMTV) sequences have been reported to be present in some human breast cancers, but it is unclear whether they have any causal role. Our findings extend the evidence that MMTV sequences found in naturally occurring mouse mammary tumors can be found in some human breast cancers, prompting further evaluation of causal roles in these settings." (Ref: Cancer Research 2010)

I don't think, sharing utensils spread breast cancer as no such evidence is there. But having a first-degree relative with breast cancer increases one's chances of getting breast cancer (due to genetic causes), and appropriate precautions like regular breast examination and mammography should be undertaken.

I hope I have answered your query.

I will be available for follow up queries if any.

Regards,

Above answer was peer-reviewed by : Dr. Jyoti Patil

Follow up: Dr. Indranil Ghosh (25 hours later)

thank you so much for answering me! I really appreciate you help. I just have 2 more questions first I'd like to ask wheather you think that the mmtv sequences as i've written in the articles are placed only in the breast cancer tissue and nowhere else in the body of the patient... Im studing microbiology and i just cant imagine how is what possible.
Second Im wondering if having a cat could be the reason of my mother illness and do you think they can transmit the virus somehow?

Answered by Dr. Indranil Ghosh (10 hours later)

Thank you for the follow up.

Yes, so far this sequences have been detected in breast cancer tissue and in some other cancers also, not in normal tissue.

Till date, no study has supported that these have been transmitted from an animal to humans.

I think this answers your second question that having a cat is not the cause for breast cancer in your mother. A cat can carry few germs to cause other infections.

Wish her Good Health.

Note: For further queries related to kidney problems Click here.

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar