Background/aim: Conventional (tubular or villous) adenomas, and the more recently described serrated adenomas, are non-invasive neoplasias that precede colon carcinomas in carcinogen-treated rats. In contrast, the histological steps antedating carcinomas in gut-associated lymphoid tissue (GALT) in rats, i.e. the third pathway of colonic carcinogenesis, remain unidentified. Aim of the study was to investigate the histological changes preceding colonic GALT carcinomas in Sprague-Dawley (SD) rats.
Materials And Methods: Archived sections from previous experiments showing GALT mucosal domains in 292 rats were re-evaluated: 276 were injected with 1,2-dimethylhydrazine (DMH) suspended in ethylenedia-minetetra-acetic acid (EDTA), and 16 were controls (8 EDTA-treated, and 8 untreated).
Results: A total of 402 colonic GALT mucosal domains were found in the 292 rats: 382 in 276 DMH-treated, 10 in eight EDTA-treated, and 10 in eight-untreated rats. In DMH-treated rats, corrupted crypts (CCS; i.e. with asymmetric fission or abnormal crypt-alignment) were recorded in 50% of the GALT domains (15% had no dysplasia and 35% had epithelial dysplasia). Adenomas on top of GALT domains were found in 7%, and GALT carcinomas in 53%. Histology of the 146 colonic GALT carcinomas revealed highly differentiated carcinomas or signet-ring cell carcinomas. EDTA-treated and untreated animals showed no dysplastic CCS, or other neoplasia.
Conclusion: This study demonstrated that GALT mucosal domains in carcinogen-treated rats often develop dysplastic CCS. Non-dysplastic CCS appear to act as scaffolds for the top-down replacement/transformation by dysplastic cells. Importantly, highly differentiated carcinomas were seen to evolve from dysplastic CCS and from adenomas, and signet-ring cell carcinomas from dysplastic goblet cells present at the base of crypts. This is the first study showing that non-invasive neoplastic lesions (dysplastic CCS and adenomas) antedate colonic GALT carcinomas in DMH-treated SD rats. The DMH-SD paradigm permits detailed study of the histological events preceding GALT carcinoma under standard laboratory conditions.
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http://dx.doi.org/10.21873/anticanres.11414 | DOI Listing |
J Infect Dis
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INSERM UMR1291-CNRS UMR5051-Université Toulouse III, Toulouse Institute for Infectious and Inflammatory Diseases F-31300, France.
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February 2024
INSERM UMR1291-CNRS UMR5051-Université Toulouse III, Toulouse Institute for Infectious and Inflammatory Diseases, Toulouse F-31300, France; CHU de Toulouse, Service des Maladies Infectieuses et Tropicales, Toulouse F-31300, France; Université Toulouse III Paul Sabatier, Toulouse F-31400, France. Electronic address:
Front Immunol
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Department of Surgery, Erasmus MC Cancer Institute, Rotterdam, Netherlands.
Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest solid tumors and is resistant to immunotherapy. B cells play an essential role in PDAC progression and immune responses, both locally and systemically. Moreover, increasing evidence suggests that microbial compositions inside the tumor, as well as in the oral cavity and the gut, are important factors in shaping the PDAC immune landscape.
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May 2023
Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Neuenhofer Weg 21, 52074 Aachen, Germany.
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Gut-associated lymphoid tissue (GALT) carcinoma, also termed dome-type carcinoma, is an infrequent distinctive subtype of colorectal adenocarcinoma and only 18 cases have been reported in the English medical literature. These tumors have unique clinicopathological features and are considered to have a low malignant potential with favorable prognosis. Herein, we described a case of a 49-year-old male with intermittent hematochezia for 2 years.
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