Functional Deconstruction of AC-T Chemotherapy Reveals Interindividual Heterogeneity and Independent Drug Action in Breast Cancer

Background/Objectives: Combination chemotherapy remains a cornerstone of breast cancer (BC) treatment, yet the relative contribution of individual drugs within standard regimens remains poorly understood. We investigated whether the activity of the widely used anthracycline-cyclophosphamide-taxane (AC-T) regimen reflects uniform benefit from all constituent drugs or heterogeneous drug-specific vulnerabilities across tumors.