A notorious hallmark associated with BCa intratumoral oxygen deprivation is an alteration in the cancer cell survival metabolism to function through the hypoxia-inducible factor-1 alpha (HIF-1α) regulatory pathway, which is an essential mediator of tumor response to hypoxia that includes the resistance of tumor cells to apoptosis (Peir et al., 2019). The gene discussed is HIF1A; the disease is neoplasm.