Subtype-specific divergent roles of calpain-1 and calpain-2 in basal A triple-negative breast cancer

These findings indicate that CAPN-1 and CAPN-2 may exert antagonistic roles in breast cancer, but importantly, this effect was restricted to HCC1937 cells, representing a basal A TNBC subtype. Validation in additional basal A models and patient-derived samples will be essential to confirm these results. Our study, therefore, provides preliminary, model-specific insights into calpain regulation in TNBC and suggests that future therapeutic strategies should carefully account for subtype heterogeneity.