Expression Of Plasma-cytoma Variant Translocation Gene 1 In Ovarian Cancer Tissue And Its Effect On The Proliferation,Migration And Invasion Of SKOV3 Cells

Ovarian cancer is the leading cause of death in gynecologic cancer,and its mortality rate occupies fifth of the world's malignant tumors.There are more than200000 newly diagnosed cases in the world each year,and more than 100000 people die each year^[1].In China,the incidence of ovarian cancer has increased in the past 10years.In 2015,new cases reached 52100 cases,and the number of cancer related deaths reached 22500 cases^[2].Because the ovary is located in the deep pelvic cavity,the early pathological changes are not easy to be found,and the late cases are also lack of effective treatment.Therefore,the mortality of ovarian cancer is the first of the gynecologic malignant tumors,which has become a major tumor that seriously threatens the life and health of women.The treatment principle of ovarian cancer is surgical treatment combined with chemotherapy.Early stage surgery was performed in all stages;in late stage,cytoreductive surgery was performed and platinum based combination chemotherapy was given to after operation^[3].The International Department of gynaecology and Obstetrics?FIGO?counted the 5 year survival rates for each stage of ovarian cancer,The IIIa period is 46.7%,the IV stage is 18.4%,and the I stage is more than 80%.The occurrence and development of ovarian cancer is a process of multi gene participation,multistage and multi-step evolution.Further study of ovarian cancer related genes is helpful to explore the mechanism of ovarian cancer occurrence and development,and has important clinical significance for finding new therapeutic targets and individualized treatment.Long non-coding RNA?lncRNA?is a class of RNA whose transcription length is larger than 200nt,and does not possess protein coding function^[4,5].In recent years,many studies have found that lncRNA can regulate gene expression in epigenetic,transcriptional and post transcriptional levels,and participate in the regulatory process of gene imprinting,chromatin remodeling,cell cycle regulation,splicing regulation,mRNA degradation and Transcriptional regulation^[6].LncRNA has important biological functions in the growth and development of cells and the development of disease,including cardiovascular disease,cancer and nervous system disease,for example Alzheimer's disease^[7].Plasmacytoma variant translocation gene 1?PVT1?is a specific lncRNA.Recent studies have shown that PVT1,as a tumor specific gene,plays an important role in gastric cancer,colorectal cancer,liver cancer,pancreatic cancer,breast cancer,ovarian cancer and many other tumors,involved in tumor cell proliferation,apoptosis,invasion and metastasis,differentiation of stem cells and drug resistance biological function.However,the molecular mechanism of long non-coding RNA PVT1 in ovarian cancer has not been elucidated.Part 1 Expression of long non-coding RNA PVT1 in ovarian cancer tissues and its relationship with clinicopathological featuresObjective:Objective to investigate the expression of long non-coding RNA PVT1 in ovarian cancer tissues and to explore the relationship between lncRNA PVT1 and the clinicopathological features of ovarian cancer.Method:1.the expression of PVT1 in the cancerous tissues of 32 ovarian cancer patients and normal ovarian tissues was detected by real time fluorescence quantitative PCR.2.using SPSS 17 statistical software,the data represented by x?±s,between the two groups using t test.Result:1.in 32 cases of ovarian cancer and normal ovarian tissue,the expression level of PVT1 in the cancer tissue was significantly higher than that in the normal ovarian tissue.2.The higher the FIGO staging and histologic classification,the higher the expression of PVT1 in the ovarian cancer tissue.Conclusion:The expression level of PVT1 in ovarian cancer tissue is significantly higher than that in normal ovarian tissue.The expression level of PVT1 was correlated with histological grade and FIGO stage in ovarian cancer patients,suggesting that PVT1plays a role in ovarian cancer.Part 2 Effect of long non-coding RNA PVT1 on the proliferation,migration and invasion of ovarian cancer SKOV3 cellsObjective:To investigate the malignant biological behavior of PVT1 in ovarian cancer SKOV3 cells,such as proliferation,invasion and migration.Method:1.Using small PVT1 interference technology,using the transfection reagent Lipofectamine 2000 and siRNA-PVT1 on SKOV3 cells in PVT1 knockout?siPVT1-1,siPVT1-2,si-NC?,real time fluorescence quantitative PCR detection of PVT1transfection efficiency;2.PVT1 knock-out cells and control cells?transfected control group si-NC,blank control group?were stained with CCK8 to detect cell proliferation ability,Cell scratch test to detect cell migration ability,and Transwell assay to detect cell invasion and migration ability.Result:1.after transfection of si-PVT1-1 and si-PVT1-2 36h,the expression level of PVT1 was significantly lower than that of si-NC and blank control group,and the transfection efficiency of siPVT1-1 was superior to siPVT1-2,the subsequent application of siPVT1-1 interfered SKOV3 cells was carried out.After knocking out the expression of PVT1,the proliferation,migration and invasion of SKOV3 cells were inhibited simultaneously.Conclusion:PVT1 is highly expressed in ovarian cancer.It can be regarded as an oncogene of ovarian cancer.Inhibition of PVT1 expression can significantly decreases the proliferation,migration and invasion of ovarian cancer SKOV3 cells,and provide a new theoretical basis for the diagnosis and targeted therapy of ovarian cancer.