Mutations of TP53 and dysfunction of the Brca1 and/or Brca2 tumor-suppressor proteins have been implicated in the molecular pathogenesis of a large fraction of OSCs , but frequent somatic mutations in other well-established tumor-suppressor genes have not been identified .
O O B-GeneOrGeneProduct O O O O B-GeneOrGeneProduct O B-GeneOrGeneProduct B-DiseaseOrPhenotypicFeature O O O O O O O O O O O O O B-DiseaseOrPhenotypicFeature O O O O O O O O B-DiseaseOrPhenotypicFeature O O O O O O