Matches in SemOpenAlex for { <https://semopenalex.org/work/W4377200661> ?p ?o ?g. }
- W4377200661 endingPage "299" @default.
- W4377200661 startingPage "233" @default.
- W4377200661 abstract "Colorectal cancer is a significant cause of morbidity and mortality in Western populations. This cancer develops as a result of the pathologic transformation of normal colonic epithelium to an adenomatous polyp and ultimately an invasive cancer. The multistep progression requires years and possibly decades and is accompanied by a number of recently characterized genetic alterations. Mutations in two classes of genes, tumor-suppressor genes and proto-oncogenes, are thought to impart a proliferative advantage to cells and contribute to development of the malignant phenotype. Inactivating mutations of both copies (alleles) of the adenomatous polyposis coli (APC) gene—a tumor-suppressor gene on chromosome 5q—mark one of the earliest events in colorectal carcinogenesis. Germline mutation of the APC gene and subsequent somatic mutation of the second APC allele cause the inherited familial adenomatous polyposis syndrome. This syndrome is characterized by the presence of hundreds to thousands of colonic adenomatous polyps. If these polyps are left untreated, colorectal cancer develops. Mutation leading to dysregulation of the K-ras protooncogene is also thought to be an early event in colon cancer formation. Conversely, loss of heterozygosity on the long arm of chromosome 18 (18q) occurs later in the sequence of development from adenoma to carcinoma, and this mutation may predict poor prognosis. Loss of the 18q region is thought to contribute to inactivation of the DCC tumor-suppressor gene. More recent evidence suggests that other tumor-suppressor genes—DPC4 and MADR2 of the transforming growth factor β (TGF-β) pathway—also may be inactivated by allelic loss on chromosome 18q. In addition, mutation of the tumor-suppressor gene p53 on chromosome 17p appears to be a late phenomenon in colorectal carcinogenesis. This mutation may allow the growing tumor with multiple genetic alterations to evade cell cycle arrest and apoptosis. Neoplastic progression is probably accompanied by additional, undiscovered genetic events, which are indicated by allelic loss on chromosomes 1q, 4p, 6p, 8p, 9q, and 22q in 25% to 50% of colorectal cancers. Recently, a third class of genes, DNA repair genes, has been implicated in tumorigenesis of colorectal cancer. Study findings suggest that DNA mismatch repair deficiency, due to germline mutation of the hMSH2, hMLH1, hPMS1, or hPMS2 genes, contributes to development of hereditary nonpolyposis colorectal cancer. The majority of tumors in patients with this disease and 10% to 15% of sporadic colon cancers display microsatellite instability, also know as the replication error positive (RER+) phenotype. This molecular marker of DNA mismatch repair deficiency may predict improved patient survival. Mismatch repair deficiency is thought to lead to mutation and inactivation of the genes for type II TGF-β receptor and insulin-like growth-factor II receptor: Individuals from families at high risk for colorectal cancer (hereditary nonpolyposis colorectal cancer or familial adenomatous polyposis) should be offered genetic counseling, predictive molecular testing, and when indicated, endoscopic surveillance at appropriate intervals. Recent studies have examined colorectal carcinogenesis in the light of other genetic processes. Telomerase activity is present in almost all cancers, including colorectal cancer, but rarely in benign lesions such as adenomatous polyps or normal tissues. Furthermore, genetic alterations that allow transformed colorectal epithelial cells to escape cell cycle arrest or apoptosis also have been recognized. In addition, hypomethylation or hypermethylation of DNA sequences may alter gene expression without nucleic acid mutation." @default.
- W4377200661 created "2023-05-22" @default.
- W4377200661 creator A5016377624 @default.
- W4377200661 creator A5016712043 @default.
- W4377200661 creator A5057092796 @default.
- W4377200661 creator A5065063060 @default.
- W4377200661 creator A5075583341 @default.
- W4377200661 creator A5087963651 @default.
- W4377200661 date "1997-09-01" @default.
- W4377200661 modified "2023-10-17" @default.
- W4377200661 title "Molecular biology of colorectal cancer" @default.
- W4377200661 cites W1493525469 @default.
- W4377200661 cites W1577146075 @default.
- W4377200661 cites W1600373583 @default.
- W4377200661 cites W1615389580 @default.
- W4377200661 cites W1673808677 @default.
- W4377200661 cites W1776471368 @default.
- W4377200661 cites W1841872817 @default.
- W4377200661 cites W1869765016 @default.
- W4377200661 cites W1894541755 @default.
- W4377200661 cites W1916476567 @default.
- W4377200661 cites W1953926689 @default.
- W4377200661 cites W1965116477 @default.
- W4377200661 cites W1966121721 @default.
- W4377200661 cites W1967243795 @default.
- W4377200661 cites W1967304777 @default.
- W4377200661 cites W1968348266 @default.
- W4377200661 cites W1968440551 @default.
- W4377200661 cites W1969345006 @default.
- W4377200661 cites W1969906973 @default.
- W4377200661 cites W1972659771 @default.
- W4377200661 cites W1973796414 @default.
- W4377200661 cites W1977284533 @default.
- W4377200661 cites W1977492313 @default.
- W4377200661 cites W1977686001 @default.
- W4377200661 cites W1978020199 @default.
- W4377200661 cites W1978419388 @default.
- W4377200661 cites W1978626016 @default.
- W4377200661 cites W1979027806 @default.
- W4377200661 cites W1979618971 @default.
- W4377200661 cites W1980178943 @default.
- W4377200661 cites W1980645806 @default.
- W4377200661 cites W1980802253 @default.
- W4377200661 cites W1980847511 @default.
- W4377200661 cites W1981112371 @default.
- W4377200661 cites W1981880025 @default.
- W4377200661 cites W1982989101 @default.
- W4377200661 cites W1983569654 @default.
- W4377200661 cites W1983673827 @default.
- W4377200661 cites W1983875037 @default.
- W4377200661 cites W1984676028 @default.
- W4377200661 cites W1985585224 @default.
- W4377200661 cites W1985793111 @default.
- W4377200661 cites W1986604538 @default.
- W4377200661 cites W1986937402 @default.
- W4377200661 cites W1986969897 @default.
- W4377200661 cites W1987886643 @default.
- W4377200661 cites W1988803575 @default.
- W4377200661 cites W1990493392 @default.
- W4377200661 cites W1990583954 @default.
- W4377200661 cites W1990727066 @default.
- W4377200661 cites W1991174950 @default.
- W4377200661 cites W1992682395 @default.
- W4377200661 cites W1994066190 @default.
- W4377200661 cites W1994811047 @default.
- W4377200661 cites W1995819860 @default.
- W4377200661 cites W1995856480 @default.
- W4377200661 cites W1996449685 @default.
- W4377200661 cites W1998663807 @default.
- W4377200661 cites W1998930133 @default.
- W4377200661 cites W1999465149 @default.
- W4377200661 cites W1999660230 @default.
- W4377200661 cites W1999810728 @default.
- W4377200661 cites W2000309947 @default.
- W4377200661 cites W2000971601 @default.
- W4377200661 cites W2001258296 @default.
- W4377200661 cites W2002678771 @default.
- W4377200661 cites W2003587234 @default.
- W4377200661 cites W2005756196 @default.
- W4377200661 cites W2006226054 @default.
- W4377200661 cites W2006611100 @default.
- W4377200661 cites W2008023178 @default.
- W4377200661 cites W2009687887 @default.
- W4377200661 cites W2010300855 @default.
- W4377200661 cites W2012867725 @default.
- W4377200661 cites W2013633208 @default.
- W4377200661 cites W2015001398 @default.
- W4377200661 cites W2015308138 @default.
- W4377200661 cites W2015354769 @default.
- W4377200661 cites W2015461236 @default.
- W4377200661 cites W2017312352 @default.
- W4377200661 cites W2018348035 @default.
- W4377200661 cites W2018538389 @default.
- W4377200661 cites W2018864636 @default.
- W4377200661 cites W2021652435 @default.
- W4377200661 cites W2026450647 @default.
- W4377200661 cites W2027737365 @default.
- W4377200661 cites W2028453587 @default.