Toggle Main Menu Toggle Search

Open Access padlockePrints

Three molecular pathways model colorectal carcinogenesis in Lynch syndrome

Lookup NU author(s): Dr Richard Gallon, Professor Sir John BurnORCiD


Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Lynch syndrome is caused by germline mutations of DNA mismatch repair (MMR) genes. MMR deficiency has long been regarded as a secondary event in the pathogenesis of Lynch syndrome colorectal cancers. Recently, this concept has been challenged by the discovery of MMR-deficient crypt foci in the normal mucosa. We aimed to reconstruct colorectal carcinogenesis in Lynch syndrome by collecting molecular and histology evidence from Lynch syndrome adenomas and carcinomas. We determined the frequency of MMR deficiency in adenomas from Lynch syndrome mutation carriers by immunohistochemistry and by systematic literature analysis. To trace back the pathways of pathogenesis, histological growth patterns and mutational signatures were analyzed in Lynch syndrome colorectal cancers. Literature and immunohistochemistry analysis demonstrated MMR deficiency in 491 (76.7%) out of 640 adenomas (95% CI: 73.3% to 79.8%) from Lynch syndrome mutation carriers. Histologically normal MMR-deficient crypts were found directly adjacent to dysplastic adenoma tissue, proving their role as tumor precursors in Lynch syndrome. Accordingly, mutation signature analysis in Lynch colorectal cancers revealed that KRAS and APC mutations commonly occur after the onset of MMR deficiency. Tumors lacking evidence of polypous growth frequently presented with CTNNB1 and TP53 mutations. Our findings demonstrate that Lynch syndrome colorectal cancers can develop through three pathways, with MMR deficiency commonly representing an early and possibly initiating event. This underlines that targeting MMR-deficient cells by chemoprevention or vaccines against MMR deficiency-induced frameshift peptide neoantigens holds promise for tumor prevention in Lynch syndrome. This article is protected by copyright. All rights reserved.

Publication metadata

Author(s): Ahadova A, Gallon R, Gebert J, Ballhausen A, Endris V, Kirchner M, Stenzinger A, Burn J, von Knebel Doeberitz M, Bläker H, Kloor M

Publication type: Article

Publication status: Published

Journal: International Journal of Cancer

Year: 2018

Volume: 143

Issue: 1

Pages: 139-150

Print publication date: 01/07/2018

Online publication date: 09/02/2018

Acceptance date: 01/02/2018

ISSN (print): 0020-7136

ISSN (electronic): 1097-0215

Publisher: Wiley


DOI: 10.1002/ijc.31300

PubMed id: 29424427


Altmetrics provided by Altmetric