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.
Güner et al. (Mon,) studied this question.