Volume 46, Issue 1 , Pages 26-32, March 2007
Molecular Carcinogenesis of Endometrial Cancer
Article Outline
Summary
In 1983, Bokhman proposed a dualistic model of endometrial tumorigenesis based on the clinical observations and clinicopathologic correlations. The majority of endometrial cancers (approximately 70–80%), designated as type I carcinomas, follow the estrogen-related pathway. Histologically, most of the type I tumors seem to arise in the background of hyperplastic endometrium, show an endometrioid differentiation, and are of low grade. Clinically, they are overall characterized by a favorable behavior. Another 10–20% of endometrial cancers, designated as type II carcinomas, follow the estrogen-unrelated pathway and arise in the background of atrophic endometrium. Type II tumors usually occur at an older age, approximately 5–10 years later than type I tumors. They are typically high-grade carcinomas of nonendometrioid differentiation, most frequently serous, less frequently clear cell. Type II carcinomas behave as an aggressive clinical course and poor prognosis. This dualistic model was subsequently supported by the molecular studies, approximately a decade later. At present, endometrioid and serous carcinoma, which represent the major phenotypes of types I and II endometrial carcinomas, respectively, are characterized by distinctive types of genetic instability and molecular alterations. In endometrioid (type I) carcinoma, four major genetic changes are responsible for the tumorigenesis, i.e. silencing of PTEN tumor suppressor gene, presence of microsatellite instability due to alterations of the mismatch repair genes, mutation of K-ras protooncogene, and alteration of β-catenin gene. On the other hand, p53 mutation and overexpression of Her2/neu oncogene are two major genetic alterations in serous and clear cell (type II) carcinomas. However, like in any model, there is evidence for exceptions. Many endometrial carcinomas are in the gray zone with overlapping clinical, morphologic, immunohistochemical, and molecular features of types I and II endometrial cancers. Finally, a small group of endometrial carcinoma is noted to be hereditary. It is known as the most common extracolonic malignancy in hereditary nonpolyposis colorectal cancer (Lynch syndrome), an autosomal dominantly inherited disorder of cancer susceptibility. Inactivation of the mismatch repair genes MSH2 and MSH6 seems to play a central role in the tumorigenesis.
Key Words: carcinogenesis , endometrial carcinoma , genetic alteration
No full text is available. To read the body of this article, please view the PDF online.
References
- . A population-based study of endometrial cancer and familial risk in younger women: Cancer and Steroid Hormone Study Group . Cancer Epidemiol Biomarkers Prev . 1996;5:411–417
- . Two pathogenetic types of endometrial carcinoma . Gynecol Oncol . 1983;15:10–17
- Case-control study of endogenous steroid hormones and endometrial cancer . J Natl Cancer Inst . 1996;88:1127–1135
- . Comparison of estrogen and progesterone receptor, Ki67, and p53 immunoreactivity in uterine endometrioid carcinoma and endometrioid carcinoma with squamous, mucinous, secretory, and ciliated cell differentiation . Hum Pathol . 1998;29:924–931
- . p53 in endometrial cancer and its putative precursors: evidence for diverse pathways of tumorogenesis . Hum Pathol . 1995;26:1268–1274
- . Endometrial intraepithelial carcinoma: a distinctive lesion specifically associated with tumors displaying serous differentiation . Hum Pathol . 1995;26:1260–1267
- . Clear cell carcinoma of the endometrium is characterized by a distinctive profile of p53, Ki-67, estrogen, and progesterone receptor expression . Hum Pathol . 1998;29:551–558
- . Pten, a protean tumor suppressor . Am J Pathol . 2001;158:1895–1898
- . PTEN signaling pathways in melanoma . Oncogene . 2003;22:3113–3122
- Altered PTEN expression as a diagnostic marker for the earliest endometrial precancers . J Natl Cancer Inst . 2000;92:924–930
- PTEN methylation is associated with advanced stage and microsatellite instability in endometrial carcinoma . Int J Cancer . 2001;91:22–26
- . PTEN mutation in endometrial cancers is associated with favorable clinical and pathologic characteristics . Clin Cancer Res . 1998;4:3005–3010
- . Microsatellite instability in endometrial carcinoma . Oncogene . 1994;9:1163–1166
- . Clinical and pathological significance of microsatellite instability in sporadic endometrial carcinoma . Am J Pathol . 1996;148:1671–1678
- . Frequency and prognostic impact of microsatellite instability in a large population-based study of endometrial carcinomas . Cancer Res . 2000;60:1750–1752
- . MLH1 promoter hypermethylation is associated with the microsatellite instability phenotype in sporadic endometrial carcinomas . Oncogene . 1998;17:2413–2417
- Methylation of hMLH1 in a population-based series of endometrial carcinomas . Clin Cancer Res . 2000;6:3607–3613
- . Altered expression of hMLH1 and hMSH2 protein in endometrial carcinomas with microsatellite instability . Hum Pathol . 2000;31:354–358
- Loss of hMSH2 and hMSH6 expression is frequent in sporadic endometrial carcinomas with microsatellite instability: a population-based study . Clin Cancer Res . 2002;8:138–143
- Mutations in DNA mismatch repair genes are not responsible for microsatellite instability in most sporadic endometrial carcinomas . Cancer Res . 1995;55:5556–5560
- Prevalence of defective DNA mismatch repair and MSH6 mutation in an unselected series of endometrial cancers . Proc Natl Acad Sci USA . 2003;100:5908–5913
- . Favorable survival associated with microsatellite instability in endometrioid endometrial cancers . Obstet Gynecol . 2001;97:417–422
- . Mutations of the Ki-ras oncogene in carcinoma of the endometrium . Am J Pathol . 1995;146:182–188
- . K-ras exon 2 point mutations in human endometrial cancer . Cancer Lett . 2001;164:207–212
- Mutation of the Ki-ras protooncogene in human endometrial hyperplasia and carcinoma . Cancer Res . 1993;53:1906–1910
- . K-ras mutation in endometrial carcinoma with microsatellite instability . J Pathol . 2001;193:193–199
- . Anticorresponding mutations of the KRAS and PTEN genes in human endometrial cancer . Oncol Res . 2000;7:567–570
- . Betacatenin mutations and aberrant nuclear expression during endometrial tumorigenesis . Br J Cancer . 2001;84:209–217
- . The Wnt signaling pathway in development and disease . Annu Rev Cell Dev Biol . 2004;20:781–810
- . Betaand gamma-catenin expression in endometrial carcinoma. Relationship with clinicopathological features and microsatellite instability . Virchows Arch . 2001;438:464–469
- . The role of cancer cell motility in invasion . Cancer Metastasis Rev . 1984;3:127–141
- . Motility and adhesive properties of high and low-metastatic murine neoplastic cells . Cancer Res . 1984;44:811–824
- . E-cadherin expression in endometrioid, papillary serous, and clear cell carcinoma of the endometrium . Obstet Gynecol . 2002;100:1290–1295
- Prognostic significance of E-cadherin protein expression in pathological stage I–III endometrial cancer . Clin Cancer Res . 2004;10:5546–5553
- . Combined E-cadherin, alpha-catenin, and beta-catenin expression is a favorable prognostic factor in endometrial carcinoma . Int J Gynecol Cancer . 2006;16:1379–1385
- . Loss of nuclear p16 protein expression is not associated with promoter methylation but defines a subgroup of aggressive endometrial carcinomas with poor prognosis . Clin Cancer Res . 2000;6:153–159
- . P16/MTS1 and pRB expression in endometrial carcinomas . Virchows Arch . 1999;434:23–28
- . The role of p16-cyclin d/CDK-pRb pathway in the tumorigenesis of endometrioid-type endometrial carcinoma . Br J Cancer . 2000;82:675–682
- Hypermethyltion in the p16 promoter region in the carcinogenesis of endometrial cancer in Japanese patients . Anticancer Res . 2006;26:851–856
- Low frequency of BRAF and CDKN2A mutations in endometrial cancer . Int J Cancer . 2005;115:930–934
- . The frequency of p53, K-ras mutations, and microsatellite instability differs in uterine endometrioid and serous carcinoma: evidence of distinct molecular genetic pathways . Cancer . 2000;88:814–824
- . Distinct sets of gene alterations in endometrial carcinoma implicate alternate modes of tumorigenesis . Cancer . 2002;94:2369–2379
- . Correlation of proliferation indices, apoptosis, and related oncogene expression (bcl-2 and c-erbB-2) and p53 in proliferative, hyperplastic, and malignant endometrium . Hum Pathol . 1998;29:1150–1159
- . Fluorescence in situ hybridization analysis of FER2/neu, c-myc, and p53 in endometrial cancer . Exp Mol Pathol . 1999;67:135–143
- Molecular pathology of endometrial hyperplasia and carcinoma . Hum Pathol . 2001;32:569–577
- . Molecular genetic pathways in various types of endometrioid carcinoma: from a phenotypical to a molecularbased classification . Virchows Arch . 2004;444:213–223
- KAI1, a metastasis suppressor gene for prostate cancer on human chromosome 11p11.2 . Science (Washington DC) . 1995;268:884–886
- KAI1 metastasis suppressor protein is down-regulated during the progression of human endometrial cancer . Clin Cancer Res . 2003;9:1393–1398
- Loss of Smad4 protein expression occurs infrequently in endometrial carcinomas . Int J Gynecol Pathol . 2003;22:347–352
- . TGF-beta signaling is disrupted in endometrioid-type endometrial carcinomas . Gynecol Oncol . 2004;95:173–180
- . p53 gene mutations are common in uterine serous carcinoma and occur early in their pathogenesis . Am J Pathol . 1997;150:177–185
- Mutations in PTEN are frequent in endometrial carcinoma but rare in other common gynecological malignancies . Cancer Res . 1997;57:3935–3940
- . Microsatellite instability is uncommon in uterine serous carcinoma . Am J Pathol . 1997;150:75–79
- . Microsatellite instability in endometrial carcinomas: clinicopathologic correlations in a series of 42 cases . Hum Pathol . 1998;29:1160–1164
- . Comparative immunohistochemical study of endometrioid and serous papillary carcinoma of endometrium . Eur J Gynaecol Oncol . 2001;22:122–126
- . HER-2/neu amplification and overexpression in endometrial carcinoma . Int J Gynecol Pathol . 1999;18:138–143
- Abnormalities of Eand P-cadherin and catenin (beta-, gamma-catenin, and p120ctn) expression in endometrial cancer and endometrial atypical hyperplasia . J Pathol . 2003;199:471–478
- . Beta-catenin and E-cadherin expression patterns in high-grade endometrial carcinoma are associated with histological subtype . Mod Pathol . 2002;15:1032–1037
- . Molecular genetic analysis of endometrial carcinoma: evidence for 2 genetically distinctive entities . Virchows Arch . 2001;439:247–252
- . p53 mutation is infrequent in clear cell carcinoma of the ovary . Gynecol Oncol . 2001;80:189–193
- Gene expression profiles of serous, endometrioid, and clear cell subtypes of ovarian and endometrial cancer . Clin Cancer Res . 2005;11:6422–6430
- Frequent hypermethylation of MLH1 promoter in normal endometrium of patients with endometrial cancers . Oncogene . 2003;22:2352–2360
- Genetics, natural history, tumor spectrum, and pathology of hereditary nonpolyposis colorectal cancer: an updated review . Gastroenterology . 1993;104:1535–1549
- . The risk of endometrial cancer in hereditary nonpolyposis colorectal cancer . Am J Med . 1994;96:516–520
- The epidemiology of endometrial cancer in hereditary nonpolyposis colorectal cancer . Anticancer Res . 1994;14:1675–1678
- . The International Collaborative Group on HNPCC. Mutations predisposing to hereditary nonpolyposis colorectal cancer: database and results of a collaborative study . Gastroenterology . 1997;113:1146–1158
- Germline mutation of MSH6 as the cause of hereditary nonpolyposis colorectal cancer . Nat Genet . 1997;17:271–272
- Lack of MSH2 and MSH6 characterizes endometrial but not colon carcinomas in hereditary nonpolyposis colorectal cancer . Cancer Res . 2001;61:2813–2815
- Microsatellite instability and hMLH1/hMSH2 expression in young endometrial carcinoma patients: association with family history and histopathology . Int J Cancer . 2000;86:60–66
- Prediction of a mismatch repair gene defect by microsatellite instability and immunohistochemical analysis in endometrial tumors from HNPCC patients . J Pathol . 2000;192:328–335
- . Familial endometrial adenocarcinoma . Clin Obstet Gynecol . 1998;41:167–171
- Molecular analysis of familial endometrial carcinoma: a manifestation of hereditary nonpolyposis colorectal cancer or a separate syndrome? . J Clin Oncol . 2005;23:4609–4616
- Microarray analysis reveals distinct gene expression profiles among different histologic types of endometrial cancer . Cancer Res . 2003;63:6–11
PII: S1028-4559(08)60102-3
doi:10.1016/S1028-4559(08)60102-3
© 2007 Taiwan Association of Obstetric & Gynecology. Published by Elsevier Inc. All rights reserved.
Volume 46, Issue 1 , Pages 26-32, March 2007
