Evaluating the indirect crosstalk between triple-negative breast cancer and fibroblasts

Breast cancer is a prevalent malignancy worldwide, affecting both genders. Understanding the communication between cancer cells and fibroblast cells in the tumor microenvironment (TME) is crucial for developing targeted therapies, especially in triple-negative breast cancer that lack common receptors.2 In this study, we investigated the indirect crosstalk between breast tumor cells (MDA-MB-468) and human foreskin fibroblast (HFF) cells by culturing them alone and in presence of conditioned media (CM) derived from one another. Proliferation was assessed through PCNA expression and MTT assay, epithelial-to-mesenchymal transition (EMT) with vimentin expression, and E-cadherin levels were quantified for and cell-cell adhesion using flow cytometry and immunostaining. Migration rates of the cells were evaluated using wound healing and Boyden chamber assays. The results showed that following exposure to tumor-derived CM, the HFF cells exhibited about 50% decrease in vimentin expression, possibly indicating mesenchymal-epithelial transition (MET), wherein the tumor cells may be secreting factors making fibroblasts become less mobile in the TME. Tumor cells exposed to HFF-derived CM showed a twofold increase in migratory rate and a decrease in E-cadherin expression. These findings suggest that secreted factors from each cell line impact the functional behavior of the other, highlighting the importance of TME interactions in developing targeted therapies.