| ObjectivesColon carcinoma is one of the most common malignant tumor in digestive system, around the world about8million new cases each year, accounting for all the malignant tumor10%～15%. In recent years, the incidence of colon carcinoma tended to increase in our country. With the development of medicine and deeply research on colon carcinoma.The occurrence, development, prognosis and treatment of colon carcinoma have a new understanding. however, colon carcinogenesis mechanism has not fully understood.So far people believe that inhibition of apoptosis and the change of autophagic activity is closely related to the occurrence and development of colon carcinoma.Cell apoptosis is controlled by gene and depends on Caspase and is an autonomous orderly programmed cell death. Under normal circumstances, cell apoptosis can keep dynamic balance of cell proliferation and cell death, ensure cell normal growth and maintain homeostasis. However, the occurrence, development of tumor existed in the inhibition of cell apoptosis phenomenon. Study found that inhibitor of apoptosis protein family (IAPs) through directly inhibit caspase and realize the function of suppression of apoptosis. The recent discovery Livin is one of the members of inhibitor of apoptosis protein family (IAPs), it is low expression or no expression in normal tissue, However, with high expression in some carcinoma cell lines. Therefore, we infer that Livin and occurrence, development of tumor has a certain relation.Autophagy is a process that eukaryotic cells utilize the lysosomal degradation of damaged organelles and macromolecules under the regulation of autophagy related gene (Atg).It plays an important role in cell metabolism and cell organelles renewal,it is a basic regulation that cells adapt to internal and external environment. Autophagy is different from apoptosis, it independ on caspase a programmed cell death. Studies revealed the change of autophagic activity existed in a variety of human tumors, therefore, hypothesized that the change of autophagic activity is closely related to the occurrence and development of colon carcinoma. Since the yeast model establishmen, on autophagy research from the cellular level rise to molecular level, The study found that the regulation of autophagy is a complicated process that it needs a variety of molecular participation, Beclinl (homologues of yeast ATG6) is mediated mammals autophagic specificity gene, it is a kind of biallelic of tumor-suppressor genes. The study found that beclinl not only participated in autophagosome formation, but also promote autophagosome mature, inducing autophagy, promoting tumor cell apoptosis and inhibiting the proliferation.In this study,The expression levels of Beclinl, Livin protein and mRNAs in colon carcinomas, colon villi adenoma,colon canalicular adenoma and normal colon mucosa were detected by immunohistochemical stain method and reverse transcription-polymerase chain reaction(RT-PCR). To study the changes of expression level of the two factors in normal tissues, precarcinomaous lesions and carcinoma tissues and discuss the relationship between its and occurrence and development of colon carcinoma.Materials and methodsCollect colon carcinoma and different types of colonic adenomas that they are have diagnosed from March2011to March2012years in the Second Affiliated Hospital of Zhengzhou University,219cases of fresh specimens were from surgical resection and colonoscopy, each get one part of the fresh tissue were preserved in RNA Waiter, after stored in-80℃ultra-low temperature refrigerator for Reverse Transcriptase-PCR(RT-PCR), another part of the fresh tissue fixed in10%formalin, embedded in paraffin, conventional continuous sections for immunohistochemistry, Meanwhile, the clinical data of patients were collected.1the protein expression levels of Beclinl,Livin were detected by immunohistochemical staining in colon carcinomas,colon villi adenoma,colon canalicular adenoma and normal colon mucosa.2The mRNA levels of Beclinl,Livin were detected by Reverse Transcriptase-PCR in colon carcinomas, colon villi adenoma,colon canalicular adenoma and normal colon mucosa.3Analysis of Beclinl and Livin expression with the clinicopathological parameters of colon carcinomas.All statistical analysis was performed using SPSS statistical version17.0. The data of immunohistochemistry staining were expressed as the mean±SEM, and were evaluated with single factor analysis of variance(ANOVA) F test; The data of RT-PCR were evaluated with Kruskal-Wallis test, P<0.05was considered as statistical significance.Results1The protein levels of Beclinl and Livin were significantly higher in the colon carcinomas than that in colonic adenoma and normal colon mucosa tissues(156.02±3.58vs.129.82±4.93vs.125.01±4.58and104.60±2.81for Beclinl,F=270.85,P=0.000;157.75±2.93vs.137.54±3.93vs.126.58±3.68and99.41±2.15for Livin, F=560.25,P=0.000).2The mRNA levels of Beclinl and Livin were significantly higher in the colon carcinomas than that in colonic adenoma and colon normal mucosa tissues (0.93±0.11vs.0.22±0.02vs.0.13±0.01and0.06±0.02for Beclinl,χ2=36.63,P=0.000;0.94±0.44vs.0.44±0.04vs.0.14±0.05and0.02±0.01for Livin,χ2=36.62, P=0.000).3Beclinl and Livin expression levels in colon carcinoma were not significantly associated with the clinicopathological parameters of patients, such as: gender, age, location, pathological type and histological grade. However, there is significantly associated with tumor size and lymph node metastasis (P<0.05). Conclusions1Expression levels of Beclinl and Livin protein and mRNA were gradually increased in normal colon mucosa, colonic tubular adenoma, colonic villous adenoma, colon carcinoma tissues, both showed dynamic changes in the process of carcinogenesis of colon carcinoma, Therefore, speculation of Beclinl and Livin may be an early event in colon carcinoma occurrence, joint detection may help to judge the trend of development of precancerous lesions,can as a marker for the detection of early colon carcinoma.2Beclinl and Livin play a certain role in colon carcinoma Continuous development, Therefore, joint detection contribute to judge prognosis and observe efficacy and monitor recurrence of colon carcinoma. |
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