HIF1A and hepatocellular carcinoma: In various types of tumors, such as hepatocellular carcinoma, neuroblastoma, and lung cancer, HIF-1α inhibition re-sensitizes cells to drug treatment; therefore, it is considered a valid target to reduce drug resistance induced by reverse hypoxia (Liu et al., 2008; Sullivan et al., 2008; Huang et al., 2010; Hartwich et al., 2013; Doktorova et al., 2015).