The Association Study Between Xinjiang Uygur People MT1XT20 Gene And Microsatellite Instability Colorectal Cancer

Background and Objective According to the epidemiological survey examination, colorectal cancer incidence increased year by year in recent years, the world of the digestive system malignant tumor of the top three, after gastric cancer and esophageal cancer. More and more become the important factor of harm to people’s life and health. So no matter abroad or domestic also pay more and more attention to all aspects of the research on colorectal cancer disease. So for the relevant factors of the disease and colorectal cancer pathogenesis, hope for early prevention, early diagnosis, effective method of early treatment. Most scholars at home and abroad think [1], colorectal cancer by various ways and lead to the onset of various factors, including changes in the structure of basic molecular is genomic instability, the instability of the genome that is mainly characterized by(1) by microsatellite DNA repetitive sequence length change of microsatellite instability type characterized by colorectal cancer(Microsatelitc instability,MSI), including Hereditary nonpolyposis colorectal cancer(Hereditary nonopolyposis colorectal cancer, HNPCC) and 10%- 15% of Sporadic colorectal cancer(Sporadic colorectal cancer, SCC).(2) is characterized by some or all of the Chromosome variation of Chromosome instability type(Chromosome instability, CIN), including 80% 85% of Sporadic colorectal cancer(Sporadic colorectal cancer, SCC). The heterogeneity of explanation settle colorectal cancer is a genetic disease. Genotype and clinical phenotype in the two types of colorectal cancer has different performance [2], which could make differences between markers for diagnosis and prognosis. Luca Morandi [3] think MT1XT20(T [20] repeat in the 3 ’untranslated region of the MT1X) gene sequences with a high correlation of microsatellite instability in colorectal and specificity. Uighurs as an important part of ethnic minorities in China’s xinjiang region, we through this study to observe MT1XT20 sequence and xinjiang uygur people colorectal cancer correlation between microsatellite instability and specificity, thus to study xinjiang uygur people microsatellite instability in colorectal cancer incidence.Methods Collection of the xinjiang uygur autonomous region people’s hospital of anorectal surgical excision of 43 cases of xinjiang uygur colorectal cancer patients with carcinoma tissue and corresponding normal tissue adjacent to carcinoma, the 43 patients with colorectal cancer by hereditary nonpolyposis colorectal cancer(HNPCC) in early screening index(that is, the level of standard Ⅱ) screening. 18 cases, of which men, women 25 cases; Up to 75 years old, the minimum 24 years old, the median age of 49.5 years old; Litres of 4 cases of colon cancer, transverse colon in 2 cases, 3 cases of sigmoid colon cancer, rectal cancer 34 cases; Each immediately after surgery for fresh tumor tissues and normal mucosa tissue adjacent to tumor(about > 5 cm from tumor tissues, hereinafter referred to as the "normal tissue). 43 Uighur population in xinjiang colorectal cancer tissue as experimental group, the corresponding normal tissue adjacent to carcinoma as control group. Choose the National Cancer Institute(National CancerInstitute, NCI) recommended five MSI testing sites: BAT26, BAT25, D2S123, D17S250, D5S346 and through gene database Chad MTIXT20 site, design primers. Using polymerase chain reaction and single-strand conformation polymorphism(PCR- SSCP) technology for MT1XT20 loci and NCI recommended five MSI testing loci and microsatellite instability colorectal cancer and corresponding adjacent normal tissues were detected and analyzed. To judge MT1XT20 with microsatellite instability in xinjiang uygur people correlation and specificity of colorectal cancer.Results Tumor tissue, as compared with the normal tissue adjacent to carcinoma appear banding allelic silver stain with mobile, missing, lengthen, shorten or electrophoresis figure shape change, namely judged microsatellite instability. The National Cancer Institute, National Cancer Institute, NCI) recommended five microsatellite loci, two or more sites judged to be unstable, namely as the height of microsatellite instability(High frequency microsatellite instability, MSI- H); Only when a site is not stable, i.e. a low-alcohol microsatellite instability(low frequency microsatellite instability, MSI- L); Does not appear unstable sites, namely a microsatellite stability(microsatellite stable, MSS) in 43 patients with xinjiang uygur, experimental detect the microsatellite change in 24 cases of carcinoma tissue, 19 cases of carcinoma of microsatellite change did not detect the overall detection rate was 55.81%, including MT1XT20(17/43), BAT- 26(19/43), the BAT- 25(16/43), D2S123(3/43), D5S346(2/43) and D17S25090(4/43); Microsatellite change in 24 cases of carcinoma tissues, more than two microsatellite loci changed 16 cases(both MSI- H), the total incidence of 55.81%, there are 8 cases of change in one site(both MSI- L), the total incidence was 18.61%. The other 19 cases without testing in place of change(MSS), total incidence was 44.19%. Which Mt1 x T20(17/43), the BAT- 26(19/43), BAT- 25(16/43), D2S123(3/43), D5S346(2/43) and D17S250 incidence of(4/43), respectively 39.53%, 44.18%, 37.20%, 6.97%, 37.20% and 9.30%. 6 loci MSI detection rate difference has no statistical significance(P > 0.05). In normal tissue adjacent to carcinoma in patients with late microsatellite change isdetected. 24 cases in xinjiang uygur people microsatellite instability in colorectal cancer MT1XT20 detection,70.83%(17/24), the BAT- 26 detection,79.16%(19/24), BAT- 25 detection,66.67%(16/24), D2S123 detection rate(3/24,15.5%), D5S346,8.33%(2/24) and D17S25090 detection,16.68%(4/24). In the MSI-h Mt1 x T20 detection rate(13/16,81.25%), MSI- L Mt1 x T20 detection rate,62.50%(5/8).Conclusion Mt1 x T20 in corresponding with the control group detection rate,39.53%(17/43), the BAT- 26 detection rate,44.18%(19/43), BAT- 25 detection rate,37.20%(16/43), D2S123 detection rate,6.97%(3/43), D5S346 detection rate(2/43,4.65%) and D17S250 detection rate,9.30%(4/43). Using SPSS 17.0 software was carried out on the data from test of X2 method of R * C, draw MT1XT20 loci exist on higher frequency of microsatellite changes(P < 0.01), suggesting MT1XT20 genes and xinjiang uygur microsatellite instability is closely related to the incidence of colorectal cancer.