Introducere. Evolutia obscura si manifestarile clinice tardive a neoplaziei epiteliale colorectale (NECR) actualmente necesita o implimentare cat mai larga a examenului genetico-molecular in vederea stabilirii diagnostic oportun. Scopul. Analiza rezultatelor cercetarilor, la nivel molecular ale genelor hMLH1, hMSH2 implicate in declansarea mecanismului de tumorogeneza. Material si Metoda. In perioada anilor 2014-2021 au fost observati si tratati un lot de 47 de bolnavi, din acestea la 21 de pacienti s-a constatat o instabilitate minisatelitica (IMS). In identificărea asocierilor genetice dintre spectrele polimorfe de ADN si manifestarile clinice ale maladiilor precanceroase (tumorogene) studiate a fost utilizata tehnica PCR a esantioanelor de ADN izolat din lotul pacientilor cercetati. Rezultate. In urma reactiei RT-PCR pe baza ARN-lui izolat din materialul biologic, au fost constatate 26 de cazuri (55,3%) cu expresie negativa, rezultat pozitiv de gradul I(+) a fost determinat in 15 de cazuri (31,9%) si gradul II(++) in 6 cazuri (12,8%). A fost confirmata originea ereditara a NECR la nivel molecular-genetic si determinata valoarea aspectului polimorf al genelor hMLH1, hMSH2. In acelasi studiu a fost examinata si frecventa de expresie a acestor gene prezente in tesuturile tumorale. Concluzie. Tehnica utilizata in studiul experimental contribuie la cresterea eficientei prognosticului medico-genetic si la screening-ul cancerului colorectal la etapele incipiente de dezvoltare.

Introduction. The obscure evolution and late clinical manifestations of colorectal epithelial neoplasia (NECR) currently require the widest possible implementation of genetic-molecular examination in order to establish a timely diagnosis. Aim of study. Analysis of research results, at the molecular level of the hMLH1, hMSH2 genes involved in triggering the mechanism of tumorigeneses. Material and method. During the years 2014-2021, a group of 47 patients were observed and treated, of which 21 minisatellite instability (IMS) was found in 21 patients. The PCR technique of the DNA samples isolated from the group of investigated patients was used to identify the genetic associations between the polymorphic DNA spectra and the clinical manifestations of the precancerous (tumorigenic) diseases studied. Results. Following the RT-PCR reaction based on RNA isolated from biological material, 26 cases (55.3%) with negative expression were found, a positive result of grade I (+) was determined in 15 cases (31, 9%) and grade II (++) in 6 cases (12.8%). The hereditary origin of NECR at the molecular-genetic level was confirmed and the value of the polymorphic aspect of the hMLH1, hMSH2 genes was determined. In the same study, the frequency of expression of these genes present in tumor tissues was also examined. Conclusion. The technique used in the experimental study contributes to the increase of the efficiency of the medical-genetic prognosis and to the screening of the colorectal cancer in the early stages of development.