Differential Effects of Afatinib on Cytokine- and Oncology-Related Profiles in Mesenchymal and Basal-Like 1 Triple-Negative Breast Cancer Cells

Triple-negative breast cancer (TNBC) is an aggressive subtype associated with high recurrence, metastasis, and mortality rates. Elevated epidermal growth factor receptor (EGFR) expression in TNBC cells positions it as a promising target for tyrosine kinase inhibitors (TKIs). This study compared the effects of afatinib on cytokine- and oncology-related profiles in mesenchymal BT549 vs. basal-like 1 MB468 TNBC cell lines. We assessed cytotoxicity, signaling pathways, cytokine- and oncology-related protein expression, and overall survival, using cell viability assay, immunoblots, human proteomic arrays, and TNBC datasets. Afatinib exhibited superior cytotoxicity compared to erlotinib, gefitinib, and lapatinib in both TNBC cells. Afatinib suppressed AKT and ERK activation in both cell lines and reduced vimentin and N-cadherin expression in BT549 cells. As cytokines are involved in TNBC development and progression, afatinib altered cytokine-related profiles, decreasing CD147, FGF2, GDF-15, and MIF, with variable CD71 and uPAR expression in BT549 cells, and reducing CD147 and PDGFB in MB468 cells. Oncology-related profile analysis showed decreased FGF2, GAL3, p53, survivin, and vimentin, and increased CTSD, HSP32, and PGRN in BT549 cells, while capG, GAL3, nectin-4, p53, and survivin were reduced in MB468 cells. Notably, elevated GAL3 and nectin-4 expressions were correlated with worse overall survival in basal-like 1 TNBC patients. In conclusion, afatinib exhibits superior cytotoxicity and selectively modulates cytokine- and oncology-related signatures in TNBC subtypes, warranting further mechanistic and in vivo studies to evaluate its therapeutic potential for TNBC.