title: Chromosome instability and carcinogenesis: insights from murine models of human pancreatic cancer associated with BRCA2 inactivation.
abstract: Chromosomal instability is a hallmark of human cancer cells, but its role in carcinogenesis remains poorly resolved. Insights into this role have emerged from studies on the tumour suppressor BRCA2, whose inactivation in human cancers causes chromosomal instability through the loss of essential functions of the BRCA2 protein in the normal mechanisms responsible for the replication, repair and segregation of DNA during cell division. Humans who carry heterozygous germline mutations in the BRCA2 gene are highly predisposed to cancers of the breast, ovary, pancreas, prostate and other tissues. Here, we review recent studies that describe genetically engineered mouse models (GEMMs) for pancreatic cancer associated with BRCA2 mutations. These studies not only surprisingly show that BRCA2 does not follow the classical Knudson "two hit" paradigm for tumour suppression, but also highlight features of the interplay between TP53 inactivation and carcinogenesis in the context of BRCA2 deficiency. Thus, the models reveal novel aspects of cancer evolution in carriers of germline BRCA2 mutations, provide new insights into the tumour suppressive role of BRCA2, and establish valuable new preclinical settings for testing approaches to pancreatic cancer therapy; together, these features emphasize the value of GEMMs in cancer research.
authors.affiliation: University of Cambridge, Medical Research Council Cancer Cell Unit, Hutchison/MRC Research Centre, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Liam D
authors.initials: LD
authors.lastname: Cassidy
authors.affiliation: University of Cambridge, Medical Research Council Cancer Cell Unit, Hutchison/MRC Research Centre, Hills Road, Cambridge CB2 0XZ, United Kingdom.
authors.forename: Siong-Seng
authors.initials: SS
authors.lastname: Liau
authors.affiliation: University of Cambridge, Medical Research Council Cancer Cell Unit, Hutchison/MRC Research Centre, Hills Road, Cambridge CB2 0XZ, United Kingdom. Electronic address: arv22@hutchison-mrc.cam.ac.uk.
authors.forename: Ashok R
authors.initials: AR
authors.lastname: Venkitaraman
mesh_terms: D000818:Animals; D024682:BRCA2 Protein / Q000235:genetics / Q000378:metabolism*; D002471:Cell Transformation, Neoplastic; D043171:Chromosomal Instability; D002877:Chromosomes, Human / Q000235:genetics / Q000378:metabolism*; D004260:DNA Repair; D004261:DNA Replication / Q000235:genetics; D004273:DNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D018095:Germ-Line Mutation; D006801:Humans; D051379:Mice; D009374:Neoplasms, Experimental / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology
chemical_list: D024682:BRCA2 Protein; C551750:BRCA2 protein, human; C106711:BRCA2 protein, mouse; D004273:DNA, Neoplasm
keywords: BRCA2; Chromosomal instability; Genetically engineered mouse model; Hereditary cancer predisposition; Pancreatic cancer