ERBB2 and breast carcinoma: In contrast, following MEKi exposure for 72 h in the human HER2‐amplified breast cancer cell line SKBr3, CD73 expression remained unchanged (Fig. 1C), while we consistently observed significant downregulation of CD73 expression and decreased enzymatic activity upon MEKi exposure in the human NSCLC cell line A549, and the human colon cancer cell line HCT116 (Fig. 1D–G).