HIF1A and nasopharyngeal carcinoma: It has been reported that under hypoxic conditions activated hypoxia-inducible factor-1α (HIF-1α) directly binds to the CBX7 gene promoter and activates the expression of CBX7, and hypoxia-induced overexpression of CBX7 stimulates the proliferation of nasopharyngeal carcinoma cells in the ischemic brain (Chiu et al., 2020).