Objective: To explore the effect of down-regulation of retinol binding protein 2 (RBP2) expression on the biological characteristics of ovarian cancer cells and its mechanism. Methods: Knockdown of RBP2 and cisplatin (DDP)-resistant ovarian cancer cell line SKOV3/DDP-RBP2i was established, the negative control group and blank control group were also set. Cell counting kit 8 (CCK-8) was used to detect the cell proliferation ability, flow cytometry was used to detect cell apoptosis, scratch test and Transwell invasion test were used to detect cell migration and invasion ability, real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) and western blot were used to detect the expressions of molecular markers related to epithelial-mesenchymal transition (EMT). The effect of RBP2 on the growth of ovarian cancer was verified through experiment of transplanted tumors in nude mice, and the relationships between RBP2 expression and tumor metastasis and patient prognosis were analyzed using the clinical data of ovarian cancer in TCGA database. Results: After down-regulating the expression of RBP2, the proliferation ability of SKOV3/DDP cell was significantly reduced. On the fifth day, the proliferation activities of SKOV3/DDP-RBP2i group, negative control group and blank control group were (56.67±4.16)%, (84.67±3.51) and (87.00±4.00)% respectively, with statistically significant difference (P<0.001). The apoptosis rate of SKOV3/DDP-RBP2i group was (14.19±1.50)%, higher than (8.77±0.75)% of the negative control group and (7.48±0.52)% of the blank control group (P<0.001). The number of invasive cells of SKOV3/DDP-RBP2i group was (55.20±2.39), lower than (82.60±5.18) and (80.80±7.26) of the negative control group and the blank control group, respectively (P<0.001). The scratch healing rate of SKOV3/DDP-RBP2i group was (28.47±2.72)%, lower than (50.58±4.06)% and (48.92±4.63)% of the negative control group and the blank control group, respectively (P<0.001). The mRNA and protein expressions of E-cadherin in the SKOV3/DDP-RBP2i group were higher than those in the negative control group (P=0.015, P<0.001) and the blank control group (P=0.006, P<0.001). The mRNA and protein expression of N-cadherin in SKOV3/DDP-RBP2i group were lower than those in the negative control group (P=0.012, P<0.001) and the blank control group (P=0.005, P<0.001). The mRNA and protein expressions of vimentin in SKOV3/DDP-RBP2i group were also lower than those in the negative control group (P=0.016, P=0.001) and the blank control group (P=0.011, P=0.001). Five weeks after the cells inoculated into the nude mice, the tumor volume of SKOV3/DDP-RBP2i group, negative control group and blank control group were statistically significant different. The tumor volume of SKOV3/DDP-RBP2i group was smaller than those of negative control group and blank control group (P=0.001). Bioinformatics analysis showed that the expression of RBP2 in patients with metastatic ovarian cancer was higher than that without metastasis (P=0.043), and the median overall survival of ovarian cancer patients with high RBP2 expression was 41 months, shorter than 69 months of low RBP2 expression patients (P<0.001). Conclusion: Downregulation of the expression of RBP2 in SKOV3/DDP cells can inhibit cell migration and invasion, and the mechanism may be related to the inhibition of EMT.
Animals ; Apoptosis ; Carcinoma, Ovarian Epithelial/genetics* ; Cell Line, Tumor ; Cell Proliferation ; Cisplatin/pharmacology* ; Drug Resistance, Neoplasm/genetics* ; Female ; Gene Silencing ; Humans ; Mice ; Mice, Nude ; Ovarian Neoplasms/pathology* ; Retinol-Binding Proteins, Cellular/metabolism*

OBJECTIVE: To analyze the expression of immunoglobulin mucin molecule 3 (TIM-3) in epithelial ovarian cancer (EOC) and the effects of TIM-3 knockdown and overexpression on proliferation and migration of ovarian cancer cells. METHODS: We analyzed TIM-3 expression in EOC and normal ovarian tissues using GEPIA database. We also detected TIM-3 expression levels in 82 surgical specimens of EOC and 18 specimens of normal ovarian tissues using immunohistochemistry, and analyzed the correlation of TIM-3 expression with clinicopathological parameters and survival outcomes of the patients. The expression of TIM-3 and Wnt1 mRNA in the tissues were detected using qRT-PCR. We constructed SKOV3 cell models of TIM-3 knockdown and overexpression and examined the changes in proliferation, apoptosis, migration and invasion of the cells using MTT assay, Annexin V-FITC/PI staining, scratch test and Transwell assay. The activity of Wnt/β-catenin pathway in the transfected was detected using dual luciferase reporter assay, and the mRNA levels of TCF-7, TCCFL-2 and CD44 were detected using qPCR. The protein expressions of MMP-9, CD44, Wnt1, β-catenin and E-cad in the transfected cells were detected with Western blotting. RESULTS: The positive expression rate of TIM-3 was significantly higher in EOC tissues than in normal ovarian tissues (P < 0.05). The expression of TIM-3 was significantly correlated with FIGO stage, histological differentiation and lymph node metastasis, and was positively correlated with Wnt1 level (P < 0.05). In SKOV3 cells, TIM-3 knockdown significantly lowered the activity of Wnt/ β-catenin pathway, inhibited cell proliferation, migration and invasion, and promoted cell apoptosis. TIM-3 knockdown significantly down-regulated the mRNA levels of TCF-7, TCFL-2 and CD44 and the protein levels of MMP-9, CD44, Wnt1 and β-catenin, and significantly up-regulated the expression level of E-cad (P < 0.05). Overexpression of TIM-3 caused opposite effects in SKOV3 cells. CONCLUSION TIM-3 is highly expressed in EOC tissue to promote malignant behaviors of the tumor cells possibly by activating the Wnt/β-catenin signal pathway.
Carcinoma, Ovarian Epithelial/pathology* ; Cell Line, Tumor ; Cell Movement/genetics* ; Cell Proliferation/genetics* ; Female ; Gene Expression Regulation, Neoplastic ; Hepatitis A Virus Cellular Receptor 2/metabolism* ; Humans ; Ovarian Neoplasms/metabolism*

Antigens, Neoplasm ; genetics ; Apoprotein(a) ; genetics ; Carrier Proteins ; genetics ; Endometriosis ; metabolism ; pathology ; Endometrium ; metabolism ; pathology ; Female ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; Membrane Proteins ; genetics ; Mutation, Missense ; genetics ; Nuclear Proteins ; genetics ; Ovarian Neoplasms ; metabolism ; pathology ; Proprotein Convertase 5 ; genetics ; Salivary Cystatins ; genetics ; Ubiquitin-Protein Ligases ; genetics ; Whole Exome Sequencing

PURPOSE: Ovarian cancer (OC) is the most fatal of gynecological malignancies with a high rate of recurrence. We aimed to evaluate the expression of solute carrier family 6, member 12 (SLC6A12) and methylation of its promoter CpG sites in a xenograft mouse model of metastatic OC, and to investigate the regulatory mechanisms that promote aggressive properties during OC progression. MATERIALS AND METHODS: Expression of SLC6A12 mRNA was determined by reverse-transcription quantitative polymerase chain reaction (RT-qPCR), and DNA methylation status of its promoter CpGs was detected by quantitative methylation-specific PCR. The metastatic potential of SLC6A12 was evaluated by in vitro migration/invasion transwell assays. Gene expression and DNA methylation of SLC6A12 and clinical outcomes were further investigated from publicly available databases from curatedOvarianData and The Cancer Genome Atlas. RESULTS: SLC6A12 expression was 8.1–14.0-fold upregulated and its DNA methylation of promoter CpG sites was 41–62% decreased in tumor metastases. After treatment with DNA methyltransferase inhibitor and/or histone deacetylase inhibitor, the expression of SLC6A12 was profoundly enhanced (~8.0-fold), strongly supporting DNA methylation-dependent epigenetic regulation of SLC6A12. Overexpression of SLC6A12 led to increased migration and invasion of ovarian carcinoma cells in vitro, approximately 2.0-fold and 3.3-fold, respectively. The meta-analysis showed that high expression of SLC6A12 was significantly associated with poor overall survival [hazard ratio (HR)=1.07, p value=0.016] and that low DNA methylation levels of SLC6A12 at specific promoter CpG site negatively affected patient survival. CONCLUSION: Our findings provide novel evidence for the biological and clinical significance of SLC6A12 as a metastasis-promoting gene.
Animals ; Carrier Proteins/genetics/*metabolism ; Cell Line, Tumor ; Cell Migration Assays ; *CpG Islands ; *DNA Methylation ; Disease Progression ; Epigenesis, Genetic ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; Mice ; Neoplasm Invasiveness ; Neoplasm Transplantation ; Ovarian Neoplasms/genetics/*metabolism/mortality/pathology ; Polymerase Chain Reaction ; Prognosis ; *Promoter Regions, Genetic ; RNA, Messenger/*metabolism ; Up-Regulation

OBJECTIVE: We aimed to evaluate the prognostic and predictive value of the nucleotide excision repair-related gene GTF2H5, which is localized at the 6q24.2-26 deletion previously reported by our group to predict longer survival of high-grade serous ovarian cancer patients. METHODS: In order to test if protein levels of GTF2H5 are associated with patients' outcome, we performed GTF2H5 immunohistochemical staining in 139 high-grade serous ovarian carcinomas included in tissue microarrays. Upon stratification of cases into high- and low-GTF2H5 staining categories (> and < or = median staining, respectively) Kaplan-Meier and log-rank test were used to estimate patients' survival and assess statistical differences. We also evaluated the association of GTF2H5 with survival at the transcriptional level by using the on-line Kaplan-Meier plotter tool, which includes gene expression and survival data of 855 high-grade serous ovarian cancer patients from 13 different datasets. Finally, we determined whether stable short hairpin RNA-mediated GTF2H5 downregulation modulates cisplatin sensitivity in the SKOV3 and COV504 cell lines by using cytotoxicity assays. RESULTS: Low expression of GTF2H5 was associated with longer 5-year survival of patients at the protein (hazard ratio [HR], 0.52; 95% CI, 0.29 to 0.93; p=0.024) and transcriptional level (HR, 0.80; 95% CI, 0.65 to 0.97; p=0.023) in high-grade serous ovarian cancer patients. We confirmed the association with 5-year overall survival (HR, 0.55; 95% CI, 0.38 to 0.78; p=0.0007) and also found an association with progression-free survival (HR, 0.72; 95% CI, 0.54 to 0.96; p=0.026) in a homogenous group of 388 high-stage (stages III-IV using the International Federation of Gynecology and Obstetrics staging system), optimally debulked high-grade serous ovarian cancer patients. GTF2H5-silencing induced a decrease of the half maximal inhibitory concentration upon cisplatin treatment in GTF2H5-silenced ovarian cancer cells. CONCLUSION: Low levels of GTF2H5 are associated with enhanced prognosis in high-grade serous ovarian cancer patients and may contribute to cisplatin sensitization.
Adult ; Aged ; Aged, 80 and over ; Biomarkers, Tumor/biosynthesis/genetics ; Cystadenocarcinoma, Serous/*genetics/metabolism/pathology ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; Kaplan-Meier Estimate ; Middle Aged ; Neoplasm Grading ; Neoplasm Proteins/biosynthesis/genetics ; Neoplasms, Glandular and Epithelial/*genetics/metabolism/pathology ; Ovarian Neoplasms/*genetics/metabolism/pathology ; Prognosis ; Transcription Factors/biosynthesis/*genetics ; Tumor Cells, Cultured

BACKGROUNDOvarian cancer is a leading gynecological malignancy. We investigated the prognostic value of programmed cell death 5 (PDCD5) in patients with ovarian cancer.

METHODSExpression levels of PDCD5 mRNA and protein were examined in six ovarian cancer cell lines (SKOV3, CAOV3, ES2, OV1, 3AO, and HOC1A) and one normal ovarian epithelial cell line (T29) using reverse transcription polymerase chain reaction, Western blotting, and flow cytometry. After inducing PDCD5 induction in SKOV3 cells or treating this cell line with taxol or doxorubicin (either alone or combined), apoptosis was measured by Annexin V-FITC/propidium iodide staining. Correlations between PDCD5 protein expression and pathological features, histological grade, FIGO stage, effective cytoreductive surgery, and serum cancer antigen-125 values were evaluated in patients with ovarian cancer.

RESULTSPDCD5 mRNA and protein expression were downregulated in ovarian cancer cells. Recombinant human PDCD5 increased doxorubicin-induced apoptosis in SKOV3 cells (15.96 ± 2.07%, vs. 3.17 ± 1.45% in controls). In patients with ovarian cancer, PDCD5 expression was inversely correlated with FIGO stage, pathological grade, and patient survival (P < 0.05, R = 0.7139 for survival).

CONCLUSIONSPDCD5 expression is negatively correlated with disease progression and stage in ovarian cancer. Therefore, measuring PDCD5 expression may be a good method of determining the prognosis of ovarian cancer patients.

Adult ; Aged ; Apoptosis Regulatory Proteins ; genetics ; metabolism ; Cell Line, Tumor ; Female ; Humans ; In Vitro Techniques ; Middle Aged ; Neoplasm Proteins ; genetics ; metabolism ; Ovarian Neoplasms ; genetics ; metabolism ; pathology ; Prognosis ; Young Adult

Epithelial ovarian cancers (EOCs) are highly lethal gynecological malignancies with a high recurrence rate. Therefore, developing prognostic markers for recurrence after chemotherapy is crucial for the treatment of ovarian cancers. As ovarian cancers frequently respond to DNA-damaging agents, we assessed the clinicopathological significance of key double-strand DNA break (DSB) repair genes, including BRCA1, BRCA2, BARD1, ATM, RAD51 and NBS1 in EOC cell lines and paraffin-embedded tissue sections from 140 EOC patients treated with cytoreductive surgery, followed by platinum-based chemotherapy. These samples were analyzed for the clinicopathological impact of DSB genes by western blot analysis, immunohistochemistry and quantitative real-time PCR. Of the DSB repair genes, BRCA1, ATM and NBS1, which are involved in the homologous recombination-mediated repair pathway, were related to aggressive parameters in EOC. When survival analysis was performed, NBS1 expression exhibited an association with EOC recurrence. Specifically, increased NBS1 expression was found in 107 out of 140 cases (76.0%) and correlated with advanced stage (P=0.001), high grade (P=0.001) and serous histology (P=0.008). The median recurrence-free survival in patients with positive and negative expression of NBS1 was 30 and 78 months, respectively (P=0.0068). In multivariate analysis, NBS1 was an independent prognostic factor for the recurrence of EOC. Together, these results suggest that NBS1 is a marker of poor prognosis for the recurrence of EOC and is associated with aggressive clinicopathological parameters.
Adolescent ; Adult ; Aged ; Biomarkers, Tumor/analysis/genetics ; Cell Cycle Proteins/analysis/*genetics ; Cell Line, Tumor ; *DNA Breaks, Double-Stranded ; *DNA Repair ; Female ; *Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; Middle Aged ; Neoplasms, Glandular and Epithelial/diagnosis/*genetics/*pathology ; Nuclear Proteins/analysis/*genetics ; Ovarian Neoplasms/diagnosis/*genetics/*pathology ; Ovary/metabolism/*pathology ; Prognosis ; Real-Time Polymerase Chain Reaction ; Young Adult

OBJECTIVETo investigate the effect of estrogen (E2), progesterone(P4), and paclitaxel (taxol) on the growth of primary human ovarian cancer cells in vitro and the expression of Drosha.

METHODSHuman ovarian cancer cells were treated with estrogen, progesterone or in combination with paclitaxel in vitro. The inhibition rate of ovarian cancer cells was assessed by methyl thiazolyl tetrazolium (MTT) assay. Apoptosis rate and cell cycle were determined by FACS analysis. The relative abundence of Drosha expression was detected by real-time quantitative PCR (qRT-PCR) and Western blotting.

RESULTSThe inhibition rate of the estrogen group, progesterone group, paclitaxel group, E2(+)Taxol group, P4(+)Taxol group was (31.53 ± 8.21)%, (25.22 ± 15.50)%, (46.71 ± 4.25)%, (69.46 ± 3.71)%, and (47.35 ± 39.02)%, respectively, significantly higher than that of the control group (0%, P<0.05 for all). Relative to the ER (-) in ovarian cancer cells,Drosha mRNA expression level of estrogen group, progesterone group, paclitaxel group, E2(+) Taxol group,and P4(+)Taxol group was 1.62 ± 0.10,1.60 ± 0.10,1.75 ± 0.16,1.95 ± 0.20, and 1.53 ± 0.06, respectively, significantly higher than that of the control group (1.00, P<0.05 for all). Relative to the ER (+)in ovarian cancer cells,the Drosha mRNA expression level of estrogen group, progesterone group, paclitaxel group, E2(+)taxol group, and P4(+)Taxol group was 1.03 ± 0.14, 1.60 ± 0.09, 1.75 ± 0.16, 1.60 ± 0.10, 1.53 ± 0.06, respectively except estrogen group, significantly higher than that of the control group (1.00, P<0.05). Relative to the ER (-) in ovarian cancer cells, the Drosha protein expression levels of the control group, estrogen group, progesterone group, paclitaxel group, E2(+) taxol group, and P4(+) Taxol group were 0.25 ± 0.05, 0.87 ± 0.30, 0.85 ± 0.38, 1.30 ± 0.21, 1.75 ± 0.83, 1.62 ± 0.82, respectively, with a significant difference between the experimental groups and the control group (P<0.05). Relative to the ER(+)ovarian cancer cells, the Drosha protein expression levels in the estrogen group, progesterone group, paclitaxel group, E2(+) taxol group, and P4(+) taxol group, were 0.28 ± 0.16, 0.85 ± 0.38, 1.30 ± 0.21, 0.94 ± 0.18, and 1.62 ± 0.82, respectively except estrogen group, significantly higher than that of the control group (0.25 ± 0.05, P<0.05 for all).

CONCLUSIONSEstrogen and progesterone in combination with paclitaxel can inhibit the growth of human ovarian cancer cells in vitro, and affect the cell apoptosis rate. Estrogen and taxol can alter the cell cycle. Estrogen and progesterone combined with paclitaxel show tumor suppressing or sensitizing effect through upregulated Drosha expression, and are associated with the estrogen receptor expression.

Antineoplastic Agents, Phytogenic ; pharmacology ; Antineoplastic Combined Chemotherapy Protocols ; pharmacology ; Apoptosis ; Cell Cycle ; Cell Growth Processes ; drug effects ; Cell Line, Tumor ; Coloring Agents ; Drug Therapy, Combination ; Estrogens ; pharmacology ; Female ; Humans ; In Vitro Techniques ; Ovarian Neoplasms ; chemistry ; drug therapy ; metabolism ; pathology ; Paclitaxel ; pharmacology ; Progesterone ; pharmacology ; RNA, Messenger ; metabolism ; Receptors, Estrogen ; metabolism ; Ribonuclease III ; genetics ; metabolism ; Tetrazolium Salts ; Thiazoles ; Up-Regulation

OBJECTIVETo study the clinicopathologic features of small cell carcinoma of ovary, hypercalcemic type (SCCOHT) and to evaluate the diagnostic significance of loss of SMARCA4 expression.

METHODSThe clinicopathologic characteristics of 5 cases of SCCOHT were reviewed. The expression of SMARCA4 protein was detected by immunohistochemistry in the cases of SCCOHT and 240 cases of other primary malignant tumors of ovary and peritoneum.

RESULTSThe mean and medium age of these patients was 30 years and 28 years, respectively. The presenting symptoms included abdominal pain, distention and a pelvic mass. Hypercalcemia was found in 3 patients. The maximum diameter of tumors ranged from 13.5 to 22.0 cm. Extraovarian spread was demonstrated in all of the patients on presentation. Histologically, the tumors were composed of closely packed small round cells with scanty cytoplasm, hyperchromatic nuclei and irregular chromatin clumps. The tumor cells grew in sheets, nests, cords or trabecular pattern. Follicle-like spaces were observed in 4 cases. Three of the tumors contained large cells with abundant eosinophilic cytoplasm. Spindle cell morphology was found in 1 case. There were 2 cases with myxoid or hyaline stroma. Four out of five of SCCOHT cases showed loss of SMARCA4 protein while only 6.3% (15/240) of the other primary malignant tumors of ovary and peritoneum , including undifferentiated carcinoma (1/5), high-grade serous carcinoma (4.6%, 5/109), endometrioid carcinoma (7.7%, 2/26), clear cell carcinoma (1/9), mucinous carcinoma (1/5), mixed carcinoma (4.9%, 3/61), carcinosarcoma (1/9) and high-grade serous carcinoma of peritoneum (1/9), were negative.

CONCLUSIONSSCCOHT is a rare malignant tumor and often misdiagnosed as other types of ovarian small cell tumor. Loss expression of SMARCA4 protein is characteristic and facilitates the diagnosis and differential diagnosis of SCCOHT.

Adenocarcinoma, Mucinous ; Adult ; Carcinoma, Small Cell ; genetics ; metabolism ; pathology ; DNA Helicases ; genetics ; metabolism ; Female ; Humans ; Hypercalcemia ; pathology ; Immunohistochemistry ; Neoplasms, Glandular and Epithelial ; genetics ; metabolism ; pathology ; Nuclear Proteins ; genetics ; metabolism ; Ovarian Neoplasms ; genetics ; metabolism ; pathology ; Transcription Factors ; genetics ; metabolism

PURPOSE: Recent discoveries suggest that aberrant DNA methylation provides cancer cells with advanced metastatic properties. However, the precise regulatory mechanisms controlling metastasis genes and their role in metastatic transformation are largely unknown. To address epigenetically-regulated gene products involved in ovarian cancer metastasis, we examined the mechanisms regulating mucin 13 (MUC13) expression and its influence on aggressive behaviors of ovarian malignancies. MATERIALS AND METHODS: We injected SK-OV-3 ovarian cancer cells peritoneally into nude mice to mimic human ovarian tumor metastasis. Overexpression of MUC13 mRNA was detected in metastatic implants from the xenografts by expression microarray analysis and quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The DNA methylation status within the MUC13 promoter region was determined using bisulfite sequencing PCR and quantitative methylation-specific PCR. We evaluated the effects of exogenous MUC13 on cell invasion and migration using in vitro transwell assays. RESULTS: MUC13 mRNA expression was up-regulated, and methylation of specific CpG sites within the promoter was reduced in the metastatic implants relative to those in wild-type SK-OV-3 cells. Addition of a DNA methyltransferase inhibitor to SK-OV-3 cells induced MUC13 expression, thereby implying epigenetic regulation of MUC13 by promoter methylation. MUC13 overexpression increased migration and invasiveness, compared to control cells, suggesting aberrant up-regulation of MUC13 is strongly associated with progression of aggressive behaviors in ovarian cancer. CONCLUSION: We provide novel evidence for epigenetic regulation of MUC13 in ovarian cancer. We suggest that the DNA methylation status within the MUC13 promoter region may be a potential biomarker of aggressive behavior in ovarian cancer.
Animals ; Cell Line, Tumor ; *DNA Methylation ; Epigenesis, Genetic ; Female ; *Gene Expression Regulation, Neoplastic ; Heterografts/metabolism ; Humans ; Mice ; Mice, Nude ; Mucins/*genetics/metabolism/physiology ; Neoplasm Invasiveness/genetics ; Ovarian Neoplasms/genetics/*metabolism/pathology ; RNA, Messenger/metabolism