CHEK1 and non-small cell lung carcinoma: NSCLC is one of the most common cancers worldwide, with a high mortality rate.2 As a first-line chemotherapy drug for treating NSCLC, the efficacy of gemcitabine is severely limited by drug resistance.26,27 In this study, we investigated the potential of combining CHK1 inhibitors with gemcitabine in overcoming NSCLC drug resistance.