Molecular genetics of colorectal cancer

ER Fearon - Annual Review of Pathology: Mechanisms of …, 2011 - annualreviews.org
ER Fearon
Annual Review of Pathology: Mechanisms of Disease, 2011annualreviews.org
Over the past three decades, molecular genetic studies have revealed some critical
mutations underlying the pathogenesis of the sporadic and inherited forms of colorectal
cancer (CRC). A relatively limited number of oncogenes and tumor-suppressor genes—most
prominently the APC, KRAS, and p53 genes—are mutated in a sizeable fraction of CRCs,
and a larger collection of genes that are mutated in subsets of CRC have begun to be
defined. Together with DNA-methylation and chromatin-structure changes, the mutations act …
Over the past three decades, molecular genetic studies have revealed some critical mutations underlying the pathogenesis of the sporadic and inherited forms of colorectal cancer (CRC). A relatively limited number of oncogenes and tumor-suppressor genes—most prominently the APC, KRAS, and p53 genes—are mutated in a sizeable fraction of CRCs, and a larger collection of genes that are mutated in subsets of CRC have begun to be defined. Together with DNA-methylation and chromatin-structure changes, the mutations act to dysregulate conserved signaling networks that exert context-dependent effects on critical cell phenotypes, including the regulation of cellular metabolism, proliferation, differentiation, and survival. Much work remains to be done to fully understand the nature and significance of the individual and collective genetic and epigenetic defects in CRC. Some key concepts for the field have emerged, two of which are emphasized in this review. Specifically, the gene defects in CRC often target proteins and pathways that exert pleiotropic effects on the cancer cell phenotype, and particular genetic and epigenetic alterations are linked to biologically and clinically distinct subsets of CRC.
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