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Updated: Jun 20, 2026
Detection of Human Leukocyte Antigen Biomarkers in Breast Cancer Utilizing Label-free Biosensor Technology
Published on: March 24, 2015
Detection of human mammary tumor virus proteins in human breast cancer cells
Stella M Melana1, Irene Nepomnaschy, Jennifer Hasa
1Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029, USA. stella.melana@mssm.edu
Abstract:
Mouse mammary tumor virus (MMTV) has been proven to induce mammary cancer in mice. MMTV-like env gene sequences have been detected in one-third of the human breast tumors studied. The whole proviral structure with 95% homology to MMTV was found in two human breast tumors and was designated as human mammary tumor virus (HMTV). HMTV viral particles with betaretroviral features have been isolated. In addition, a retrovirus called human betaretrovirus (HBRV), homologous to the mentioned retroviruses, has been isolated from tissues of patients with primary biliary cirrhosis. In this report, the expression of HMTV envelope (Env) and capsid (Ca) was detected in 10 primary cultures of human breast cancer containing HMTV sequences (MSSM) by Western blot and fluorescence activated cell sorting (FACS), using a panel of antibodies against HMTV Env, HBRV Env and Ca and the MMTV Env Gp36 and Ca P27 proteins. By contrast, HMTV proteins did not react with antibody against the MMTV Env Gp52 protein. All the antibodies detected MMTV proteins with exception of two out of four monoclonal antibodies against HMTV Env. Approximately 13% of the MSSM cells showed HMTV protein expression by FACS analysis. This report shows the expression of HMTV proteins for the first time in human breast cancer cells using a panel of antibodies against HMTV, HBRV and MMTV proteins. This should be taken into consideration when MMTV antibodies are used to detect HMTV proteins in human tissues.
Insights
Human mammary tumor virus (HMTV) proteins are expressed in human breast cancer cells, as shown by Western blot and FACS analysis. This finding is crucial for accurate detection of HMTV in human tissues.
Area of Science:
- Oncology
- Virology
- Molecular Biology
Background:
- Mouse mammary tumor virus (MMTV) is known to cause mammary cancer in mice.
- MMTV-like sequences and homologous human mammary tumor virus (HMTV) have been identified in human breast tumors.
- Human betaretrovirus (HBRV) has been isolated from patients with primary biliary cirrhosis.
Purpose of the Study:
- To detect the expression of HMTV envelope (Env) and capsid (Ca) proteins in human breast cancer cells.
- To investigate the cross-reactivity of antibodies against HMTV, HBRV, and MMTV proteins.
Main Methods:
- Western blot and fluorescence-activated cell sorting (FACS) were used to detect protein expression.
- A panel of antibodies against HMTV, HBRV, and MMTV Env and Ca proteins was employed.
- Primary cultures of human breast cancer cells containing HMTV sequences (MSSM) were analyzed.
Main Results:
- HMTV Env and Ca proteins were detected in approximately 13% of MSSM cells.
- Antibodies against HMTV Env, HBRV Env and Ca, and MMTV Env Gp36 and Ca P27 proteins showed reactivity.
- HMTV proteins did not react with antibodies against MMTV Env Gp52, and some HMTV Env antibodies showed limited reactivity with MMTV proteins.
Conclusions:
- This study provides the first evidence of HMTV protein expression in human breast cancer cells.
- The findings highlight the importance of antibody specificity when detecting HMTV proteins in human tissues to avoid cross-reactivity with MMTV.
- Further research is warranted to understand the role of HMTV in human breast cancer pathogenesis.
