DEPDC1 Gene Expression In Ovarian Cancer Tissues And Its Effect On Ovarian Cancer Cell Proliferation And Invasive Metastatic Capacity

Background:Ovarian cancer is a high-incidence female malignancy,and initial symptoms are obscure,so early diagnosis is difficult,with 60 to 70 percent of the cases reaching late stages at presentation.Although the incidence of ovarian cancer is lower than that of cervical and endometrial cancers,the mortality rates far exceed those of other gynecological malignancies and pose a significant threat to women.Therefore,the search for effective early diagnostic markers and therapeutic targets has significant implications for reducing the incidence and mortality of ovarian cancer.DEPDC1 is an important protein that contains a domain of DEP,a 100 amino acid residue α-helical and β-helical secondary structure,named after the three proteins found in Dishevelle,EGL-10,and Pleckstrin.The DEPDC1 protein coding gene,depdc1,is located on chromosome 1p31.2 and is 23 kb long.DEPDC1 has been shown to help maintain centrosomal integrity and plays an important role in regulating mitotic progression.Recent studies suggest that DEPDC1 is overexpressed in a variety of tumors,such as renal,esophageal,and hepatocellular carcinomas,and may serve as a diagnostic marker and therapeutic target for these cancers.In addition,the use of a peptide vaccine derived from DEPDC1 has been studied clinically in gastric and bladder cancers,respectively,with favorable prospective results.In a tumour database analysis,DEPDC1 was found to be highly expressed in borderline ovarian tumors and in ovarian cancers and to be poorly expressed in normal and benign ovarian tissues,but the mechanism of its role in ovarian cancer remains unclear.Objectives:Part I: Exploring the expression and clinical significance of DEPDC1 in ovarian cancer tissues:(1)DEPDC1 expression in ovarian cancer tissue by database analysis;(2)observe the expression of DEPDC1 in ovarian cancer tissues by immunohistochemical staining;and(3)analyze the expression of DEPDC1 genes in ovarian cancer tissues and their relationship to ovarian cancer prognosis by clinicopathological data of patients with ovarian cancer.Part II:To explore the effect of knockdown of DEPDC1 on proliferation and invasive metastasis of ovarian cancer cell lines:(1)to explore the effect of knockdown of DEPDC1 on proliferation of ovarian cancer cell lines HO-8910 and SK-OV-3;(2)to explore the effect of knockdown of DEPDC1 on invasive metastasis ability of ovarian cancer cell lines HO-8910 and SK-OV-3.Part III: To investigate the effect of knockdown of DEPDC1 on subcutaneous tumorigenesis of ovarian cancer cells in nude mice.Materials and Methods:Part I:(1)The GSE54388 ovarian cancer gene expression data set was downloaded from the GEO public database for principal component analysis and significant difference analysis;DEPDC1 expression in ovarian cancer was analyzed from the TCGA database;DEPDC1 expression and survival in ovarian cancer patients were analyzed online from the Kaplan-Meier Plotter.(2)Differences in DEPDC1 expression by immunohistochemical staining in paraffin-stained specimens from 154 ovarian cancers and 27 normal ovarian tissues.(3)Analysis of correlations between DEPDC1 expression levels in ovarian cancer tissue and histologic data and survival in ovarian cancer patients using SPSS 25.0 software in an assembled tissue microarray database.Part II:(1)Human ovarian cancer cells HO-8910 and SK-OV-3 were selected to construct knockdown DEPDC1 ovarian cancer cell models and construct experimental and control groups;(2)the effect of knockdown DEPDC1 on ovarian cancer cell growth,proliferation,and apoptosis was observed by cell culture;(3)the effect of knockdown DEPDC1 on ovarian cancer cell migration and metastasis was observed by scratching experiments and the effect of knockdown DEPDC1 on ovarian cancer cell invasion was observed by transwell assay.Part III:(1)To construct an animal model of subcutaneous tumorigenesis in nude mice;(2)To investigate the effect of knockdown of DEPDC1 on the subcutaneous tumorigenic capacity of nude mice by recording data from subcutaneous tumorigenesis in control and control mice;and(3)To investigate the differential expression of knockdown of DEPDC1 in ovarian cancer cells following tumorigenesis by in vivo imaging.Results:Part I:(1)DEPDC1 expression was significantly higher in patients with ovarian cancer than in the normal population.(2)DEPDC1 gene expression is positively correlated with ovarian cancer pathological stage,pathological grade,tumor depth(T-value),tumor lymph node metastasis(N-value),tumor distant metastasis(M-value),and relapsing status,i.e.,Increased DEPDC1 gene expression contributes to the deepening of malignancy in patients;Patients with higher DEPDC1 gene expression are more prone to relapse.(3)DEPDC1 gene expression was significantly associated with overall and disease-free survival in ovarian cancer,with decreased survival as DEPDC1 gene expression increased in patients.Part II:(1)After DEPDC1 knockdown,there was a significant decrease in the growth and proliferation rate of ovarian cancer cells and a significant increase in apoptosis.(2)Decreased invasiveness and metastatic capacity of ovarian cancer cells after knockdown of DEPDC1.Part III:(1)Knockdown of DEPDC1 in nude mice is associated with reduced fluorescence within regions of normally expressed DEPDC1.(2)Lower subcutaneous tumour volume of ovarian cancer cells from nude mice knocked down on DEPDC1 and larger subcutaneous tumour volume of ovarian cancer cells from nude mice normally expressing DEPDC1.Conclusions:This study demonstrates that DEPDC1 is significantly overexpressed in ovarian cancer,is positively associated with the extent of malignancy and recurrence of ovarian cancer,and is negatively associated with overall and disease-free survival of ovarian cancer.After knockdown of DEPDC1,the proliferation rate of ovarian cancer cells decreased,the apoptosis rate increased,and the invasiveness and metastatic capacity decreased.Both the subcutaneous tumor size and the subcutaneous tumor rate of knockdown of DEPDC1-expressing ovarian cancer cells were significantly lower in nude mice than in ovarian cancer cells normally expressing DEPDC1.