Suppression of HERV-K Viral Gene Expression in MCF-7 Cells by Doxorubicin: Implications for Breast Cancer Therapy
Abstract
Background: Breast cancer is one of the most prevalent cancers worldwide and remains a significant cause of mortality among women. Human endogenous retrovirus-K (HERV-K) has been associated with breast cancer progression, yet the effects of chemotherapy on its gene expression are not well understood.
Methods: This study investigated the impact of doxorubicin treatment on the expression of HERV-K gag, pol, and env genes in the MCF-7 breast cancer cell line. MCF-7 cells were treated with varying concentrations of doxorubicin, and total RNA was extracted for gene expression analysis using RT-qPCR. In parallel, apoptosis assays were conducted to evaluate the cytotoxic effects of doxorubicin and determine the IC₅₀ value.
Results: RT-qPCR analysis revealed that doxorubicin exposure significantly reduced the transcriptional levels of the HERV-K gag, pol, and env genes. Apoptosis assays confirmed effective cytotoxicity of doxorubicin, with an IC₅₀ deter-mined to be 1 µg/mL.
Conclusion: These findings suggest that doxorubicin modulates endogenous retroviral activity in breast cancer cells, po-tentially contributing to its therapeutic effects. The downregulation of HERV-K genes may represent a novel mechanism of doxorubicin action. Further research is needed to elucidate the biological significance of HERV-K suppression and evaluate its potential as a biomarker or therapeutic target in breast cancer.
Keywords
Breast cancer, HERV-K, MCF-7, RT-qPCR, Gene expression
Supporting Institution
This research received no specific grant.
Ethical Statement
This study was conducted using human breast cancer cell lines. No human or animal subjects were used. Therefore, ethical approval is not required.
Thanks
Not applicable.
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