hTERT and TP53 deregulation in intestinal-type gastric carcinogenesis in non-human primates
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Despite the high incidence, the molecular events involved in intestinal-type gastric carcinogenesis remains unclear. We previously established an intestinal-type gastric carcinogenesis model in Cebus apella, a New World monkey. In the present study, we evaluated hTERT and TP53 mRNA expression, as well as their protein immunoreactivity, in normal mucosa, non-atrophic gastritis, atrophic gastritis, intestinal metaplasia, and intestinal-type gastric cancer samples of non-human primates treated with N-methyl-nitrosourea. In addition, we evaluated the number of TP53 copies in these samples. Although hTERT immunoreactivity was only detected in gastric cancer, a continuous increase of hTERT mRNA expression was observed from non-atrophic gastritis to gastric tumors. No sample presented p53 immunoreactivity. However, we also observed a continuous decrease of TP53 mRNA expression during the sequential steps of gastric carcinogenesis. Moreover, loss of TP53 copies was observed in intestinal metaplasia and gastric cancer samples. Our study highlights that hTERT and TP53 have a key role in intestinal-type gastric cancer initiation.
KeywordshTERT TP53 Gastric carcinogenesis Non-human primates Precancerous lesions Animal model
This study was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq; MACS and RRB) and Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP; MFL and DQC) as grants and fellowship awards.
Conflict of interest
All authors declare that they have no conflicts of interest.
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