| Background Lung cancer is a high incidence and mortality of malignant tumor, the pathogenesis of lung cancer is still uncertain. microRNA-21is a kind of small noncoding RNA, participate in the regulation of gene transcription level after, in a variety of expression in tumor tissues such as esophageal cancer, gastric cancer, ovarian cancer and so on. PDCD4is a kind of tumor suppressor gene, but also an important target gene of microRNA, which occurred after the transcriptional gene silencing. The significance of microRNA-21/PDCD4pathway abnormal in the development of lung cancer currently is rarely reported. microRNA-21and PDCD4expressions were detected by real-time fluorescence quantitative PCR (qRT-PCR) and other means in this topic so as to explore the effects of microRNA-21/PDCD4pathway abnormal in the development of lung squamous cell carcinoma in rats and provide new ideas and scientific basis for prevention and treatment for lung cancer.Objective The object is to analysis the correlation between the microRNA-21and PDCD4and to explore its clinical significance through detecting the expressions of microRNA-21and PDCD4in rat lung squamous carcinomas in the process of case.Methods1. To build the rat model of lung cancer:60rats were randomly divided into experimental group. The iodized oil contains carcinogenic solvent solution0.1ml was injected into bronchial of rats.10rats were randomly divided into control group.In the left lower lobe bronchus,0.1ml iodine oil was injected into. Killed rats on time, got lung squamous carcinoma specimens of each stage in the process of formation, made paraffin embedding blocks, HE staining was did, the microscopic diagnosis was classificated.2. The expressions of microRNA-21of diseased tissue in various stages were detected by qRT-PCR.3. The situ hybridization was used to detect the expression of PDCD4in every phase of the diseased tissues at mRNA level.4. The immunohistochemistry was used to detecte the expression of PDCD4in various stages of diseased tissue at protein level.5. SPSS17.0statistical software was used to analysis the data.Results1. Animal ModelsThe rate of induced cancer successfully was up to80%(48/60) in60experimental rat models. Specimens of cancerous lesions include multiple phases:21cases were bronchial epithelial hyperplasia,15cases were atypical hyperplasia,26cases were invasive cancer,20cases were metastatic cancer.The tumor was not found in the10rats of control group.2. The expression of microRNA-21The expression results of microRNA-21are as follows:the control group,0.0019±0.0009; atypical hyperplasia group,0.0190±0.0027; infiltrating carcinoma group,0.0608±0.0051; metastatic carcinoma group,0.1591±0.0255. There are differences between control and experimental group (P<0.05), there are also differences between the experimental groups (P<0.05).3. The expression of PDCD4The expression results of PDCD4mRNA are as follows:the control group was0.6930±0.1243; atypical hyperplasia group was0.5600±0.1006; infiltrating carcinoma group was0.4900±0.1900; metastatic carcinoma group was0.3982±0.1212. The difference between the experimental group and the control group was statistically significant (P<0.05). The differences were statistically significant in each two groups(P <0.05).According to the immunohistochemical grading standard, results of PDCD4protein expression in different stages are as follows:the control group was0.7050±0.1327; atypical hyperplasia group was0.5747±0.1601; infiltrating carcinoma group was0.4717±0.0710; metastatic carcinoma group was0.3700±0.1042. There are significant difference between control and experimental group (P<0.05), there are also differences between the experimental groups of atypical hyperplasia and infiltrating carcinoma group and the metastatic carcinoma (P<0.05). The expressions of PDCD4protein in the cancer tissues were lower than atypical hyperplasia group and the control group (P<0.05). The detection results of protein and gene expression by immunohistochemistry and situ hybridization are consistency (r=0.875, P<0.05).4. The correlation between microRNA-21and PDCD4The gene expression of microRNA-21and PDCD4in lung squamous carcinoma tissues were negative feedback (r=-0.582, P<0.01), and the protein expression of microRNA-21and PDCD4were also negative feedback (r=-0.598, P<0.01).Conclusions1.The expression of microRNA-21/PDCD4which are feedback are closely related with occurrence and development of lung cancer, combining the two detection is favor for early diagnosis of lung cancer.2. microRNA-21can inhibit the expression of PDCD4and can be used as a potential therapeutic target for lung cancer. |
PDF Full Text Request