title: Deletion of essential functions and tumorigenesis.
mesh_terms: D002454:Cell Differentiation; D002471:Cell Transformation, Neoplastic; D006801:Humans; D009369:Neoplasms / Q000209:etiology* / Q000473:pathology; D009751:Nutritional Requirements; D010641:Phenotype; D014802:Vitamin A Deficiency / Q000150:complications