HIF1A and neuroblastoma: Activation of CHAF1A expression promotes a malignant cellular phenotype; CHAF1A gain‐of‐function increases cell proliferation to a greater extent under hypoxic conditions, supporting the original identification of CHAF1A as potential HIF‐1α target.[57] In addition, CHAF1A activates oncogenic transformation in vitro and is sufficient to initiate tumor formation in vivo, suggesting a critical role for CHAF1A in NB oncogenesis.