ERBB2 and breast carcinoma: In this study MDA-MB231 cells, a triple negative breast cancer (TNBC) subtype, and SKBR3, a HER2 enriched breast cancer subtype, were used to study the effect of 3D cell culture on responsiveness to doxorubicin an anthracycline chemotherapeutic agent which functions by intercalating DNA, inhibiting topoisomerase II and preventing DNA recombination.