MMTV-like env gene sequences in human breast cancer
Y Wang1, I Pelisson, S M Melana
1Department of Pathology, Mount Sinai School of Medicine, New York, New York 10029, USA.
Archives of Virology
|March 27, 2001
Summary
A mouse mammary tumor virus (MMTV) env gene-like sequence was found in human breast cancer, suggesting an external source. This finding supports a potential exogenous origin for MMTV sequences in breast cancer tissues.
Area of Science:
- Oncology
- Virology
- Molecular Biology
Background:
- A specific retroviral sequence, similar to the MMTV env gene, has been identified in a significant portion of human breast cancers.
- This sequence was notably absent in normal human tissues and other tumor types, raising questions about its origin.
Purpose of the Study:
- To further investigate the nature and origin of the MMTV env gene-like sequences detected in human breast cancer.
- To compare these sequences with known MMTV strains and endogenous retroviral sequences.
Main Methods:
- Sequence analysis of MMTV env gene-like fragments from eleven human breast tumors and three cell lines.
- Comparative sequence analysis against four MMTV strains and established endogenous retroviral sequences.
Main Results:
- The breast cancer-derived sequences exhibited high homogeneity with MMTV sequences.
- Conversely, these sequences showed low homology to known endogenous retroviral sequences found in the human genome.
Conclusions:
- The findings strongly suggest that the detected MMTV env gene-like sequences in human breast cancer originate from an external source (exogenous).
- This supports the hypothesis of an exogenous retroviral involvement in human breast carcinogenesis.
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