ERBB2 and small cell lung carcinoma: We found that human epidermal growth factor receptor 2 (HER2) was expressed in small‐cell lung cancer (SCLC) parental cell lines (SBC‐3) and its chemoresistant cell lines, and HER2 was upregulated in chemoresistant SCLC cells, especially CDDP‐resistant cells (SBC‐3/CDDP).