Cell proliferation and drug sensitivity tests were applied to analyze the biological role of MPZL3 and drug sensitivities in breast cancer....In contrast, the group with higher MPZL3 expression was more sensitive to lapatinib, erlotinib, and ZD-6474, which specifically target EGFR, more sensitive to AZD0530, which targets ABL, and more sensitive to TKI258, which targets FGFR.