Expression Of Grim-19 Gene And Its Relationship With Clinical And Pathological Characteristics Of Lung Cancer Patients

BackgroundGene associated with retinoid interferon-induced mortality(GRIM)-19, was originally identified as a cell death regulatory gene using the antisense technical knockout approach by Angell et al. In a number of primary RCC and in some urinogenital tumors.the expression of Grim-19 is lost or severely depressed .By using an RCC cell line, researchers show that down regulation of Grim-19 promotes tumor growth via an augmentation of Stat3-dependent gene expression. These studies for the first time show a tumor suppressor like activity of Grim-19. Maximo et al confirmed that Hurthle cell tumors exist mutation of Grim-19. As researches on Grim-19 expression in lung cancer tissues have not yet been reported both at home and abroad, In this study, We detected mRNA expression of Grim-19 ,Stat3 and it's downstream target gene Bcl2, CyclinB1,CyclinD1,c-Myc in 40 cases lung cancer tissues using RT-PCR, For further quantitative Grim-19 mRNA expression, we used the methods real time quantitive RT-PCR. verify Grim-19 protein expression levels using western blot, Analyzing the relationship between Grim-19 mRNA and clinicopathological features, and to further explore the role of Grim-19 in lung cancer carcinogenesis and the association with the development of lung cancer.ObjectiveIn the present study, we used lung cancer and adjacent tissues to investigate the expression of Grim-19, Stat3 and it's downstream target gene Bcl2, CyclinB1,CyclinD1,c-Myc, Analyzing the relationship between Grim-19 mRNA and clinicopathological features, and to further explore the role of Grim-19 in lung cancer carcinogenesis and the association with the development of lung cancer. Method1. Detect Grim-19, Stat3 and its downstream target genes Bcl2, CyclinB1, CyclinD1, c-Myc mRNA expression in 40 cases lung cancer and adjacent tissues using RT-PCR analysisTotal RNA were extracted from 40 cases lung cancer and adjacent tissues, respectively, and the expression of Grim-19, Stat3 and its downstream target genes Bcl2, CyclinB1, CyclinD1, c-Myc was measured by RT-PCR.2. Quantitative Grim-19 mRNA expression in 40 cases lung cancer and adjacent tissues using real time RT-PCR analysisTotal RNA were extracted from 40 cases lung cancer and adjacent tissues, respectively, and the expression of Grim-19 was measured by real time RT-PCR.3. Protein extraction and Western blot analysisTotal protein were extracted from 40 cases lung cancer and adjacent tissues, respectively, and the expression of Grim-19 was measured by Western Blot.4. Analyze the relationship between Grim-19 mRNA in lung cancer tissues and clinicopathological features of patientsSet 40 cases Grim-19 mRNA expression in lung cancer tissues according to sex, histological type, clinical staging, age and smoking index , then Analyze the relationship between Grim-19 mRNA in lung cancer tissues and clinicopathological features of patients.5. Statistical methodAll experiments were performed at least three independent times. Data were expressed as the means±standard and were analyzed for significant differences by independent Student's t test and one-way ANOVA with SPSS 15.0. Differences were considered statistically significant if P value <0.05.Result1. Grim-19, Stat3 and it's downstream target gene Bcl2,CyclinB1,CyclinD1,c-Myc mRNA analysis in lung cancer and adjacent tissues RT-PCR, real time RT-PCR results all indicated that: the mRNA expression of Grim-19 in lung cancer group decreased significantly compared to the corresponding adjacent group, respectively. RT-PCR results showed the mRNA expression of Stat3 and it's downstream target gene Bcl2,CyclinB1,CyclinD1,c-Myc in lung cancer tissues were significantly higher than in its'adjacent tissues.2. Grim-19 protein expression analysis in lung cancer and adjacent tissuesWestern Blot results indicated that: the protein expression of Grim-19 in lung cancer group decreased significantly compared to the corresponding adjacent group, respectively. a decrease Grim-19 mRNA expression corresponded to a similar effect on Grim-19 protein expression.3. The relationship between Grim-19 mRNA expression and clinical and pathological parameters of lung cancer patientsSet 40 cases Grim-19 mRNA expression in lung cancer tissues as five groups according to histology, TNM stage, sex, age, smoking condition .the relative amount of Grim-19 mRNA expression of stage I–II were significantly higher than those of stage III-IV. However, the expression of Grim-19 was determined not to be associated with the patients'sex, age, smoking condition, histology.Conclusion1. The expression of Grim-19 mRNA and protein in lung cancer group decreased significantly compared to the corresponding adjacent group, respectively. a decrease Grim-19 mRNA expression corresponded to a similar effect on Grim-19 protein expression.;2. The relative amount of Grim-19 mRNA expression of stage I–II were significantly higher than those of stage III-IV;However, the expression of Grim-19 was determined not to be associated with the patients'sex, age, smoking condition, histology.3. The mRNA expression of Stat3 and its downstream target genes Bcl2, CyclinB1, CyclinD1, c-Myc were higher in lung cancer tissues compared to the corresponding adjacent group, respectively. a decreased Grim-19 mRNA expression co-existence high expression of Stat3 in lung cancer tissues.4. Grim-19 mRNA was down-regulated in tumor tissue and the lower expression of Grim-19 mRNA may play a major role in lung cancer carcinogenesis, suggesting that it may have very intimate association with the development of lung cancer.