The Differential Expression of the JAK/STAT Pathway in Breast Cancer Cells Transfected with Human Papillomavirus...

Breast cancer is among the most prevalent and deadly types of cancer worldwide. Viral infections have been investigated as contributing factors in breast carcinogenesis, including infections by high-risk genotypes of human papillomavirus (HPV). Although viral DNA has been detected in breast tumors, the role of HPV activity in this type of cancer remains poorly understood. HPV oncogenes interact with various host genes, including those involved in the JAK/STAT signaling pathway. This pathway is associated with the regulation of gene expression related to the tumor microenvironment, and understanding how HPV oncogenes interact with JAK/STAT components may provide insights into the relationship between the virus and breast cancer development. In this study, we assessed the differential expression of the JAK/STAT pathway in MDA-MB-231 cells individually transfected with the E5, E6, and E7 oncogenes of HPV16. The results revealed downregulation of STAT4 in the presence of the E5, E6, and E7 oncogenes. Notably, cells transfected with E5 alone exhibited upregulation of JAK2, STAT3, and STAT6, whereas transfection with E6 and E7 resulted in their downregulation. These findings highlight the underexplored role of the E5 oncogene in contrast to the more extensively studied E6 and E7. Our results support the hypothesis that HPV oncogenes actively modulate the expression of genes involved in the tumor microenvironment in breast cancer.