Cancer of the ovary, fallopian tube, and peritoneum: a population-based comparison of the prognostic factors and outcomes

Chemerin Enhances Migration and Invasion of OC Cells via CMKLR1/RhoA/ROCK-Mediated EMT

Chemerin is a newly described adipokine with significant effects on obesity, metabolic disorders, and immune trafficking. Recently, chemerin has gained prominence for its potential roles in cancer and tumorigenesis with pro- or antitumor effects. To date, most referenced multifunctions of chemerin are attributed to the chemokine-like receptor 1 (CMKLR1), distributing broadly in many tissues. This study investigates the in vitro roles of chemerin treatment on migration and invasion of ovarian carcinoma cells (OVCAR-3 and SK-OV-3) and potential underlying mechanisms. Herein, exogenous chemerin treatment promotes growth and invasion of SK-OV-3 cells but has no significant effects on OVCAR-3 cells. SK-OV-3 cells undergo morphological elongation characterized by epithelial-to-mesenchymal transition (EMT) and Ras homologous genome members A (RhoA)/Rho protein-related curl spiral kinase-1 (ROCK1) activation. Furthermore, chemerin-enhanced invasion and EMT of SK-OV-3 cells are effectively blocked by C3 transferase (C3T) and Y27632 and RhoA and ROCK1 inhibitor, respectively. More importantly, RhoA/ROCK1-EMT-mediated SK-OV-3 cell invasion is orchestrated by CMKLR1 upregulation after chemerin treatment (50 ng/mL). The silencing of CMKLR1 significantly (P < 0.0001) reverses the chemerin-enhanced invasion, EMT, and RhoA/ROCK1 activation of SK-OV-3 cells. Our study indicates that chemerin promotes invasion of OC cells via CMKLR1-RhoA/ROCK1-mediated EMT, offering a novel potential target for metastasis of OC.

Prognostic Significance of the CXCLs and Its Impact on the Immune Microenvironment in Ovarian Cancer

The chemokine (C-X-C motif) ligand (CXCL) family in tumor tissue is closely related to tumor growth, metastasis, and survival. However, the differential expression profile and prognostic value of the CXCLs in ovarian cancer (OC) have not been elucidated. Therefore, we studied the expression levels and mutations of CXCLs in OC patient in TCGA and various public databases. The expression differences of CXCLs in OC cancer tissues and normal tissues were compared through the Gene Expression Profiling Interactive Analysis (GEPIA) database. The effect of CXCLs on OC prognosis was analyzed using the Kaplan-Meier curves in GEPIA database. The impact of CXCLs on immune infiltration and clinicopathological outcomes in OC was assessed using the TIMER algorithm. Compared with normal tissues, we found that eight CXCLs were significantly differentially expressed in OC. The expression levels of CXCL9 (P = 0.0201), CXCL11 (P = 0.0385), and CXCL13 (P = 0.0288) were significantly associated with tumor stage. CXCL13 was the only gene that significantly affected both disease-free survival (DFS) and overall survival (OS) in OC, and higher CXCL13 transcript levels implied longer DFS and OS. Although there was no significant impact on DFS, CXCL10 (P = 0.0079) and CXCL11 (P = 0.0011) expression levels had a significant effect on OS in OC. At the same time, CXCLs were significantly associated with several immune-infiltrating cells in OC tissues. The CXCLs were significantly associated with one or more immune-infiltrating cells in OC tissue. CXCL13 was differentially expressed in OC and significantly affected the prognosis of patients and was a potential marker of OC prognosis.

Knockdown of circ-PIP5K1A overcomes resistance to cisplatin in ovarian cancer by miR-942-5p/NFIB axis

Cisplatin (DDP)-based chemotherapy is the main chemotherapeutic agent for ovarian cancer (OC) treatment. Circular RNA PIP5K1A (circ-PIP5K1A) was found to promote OC tumorigenesis. However, whether circ-PIP5K1A was involved in DDP resistance in OC remains unclear. Levels of circ-PIP5K1A, microRNA (miR)-942-5p, and nuclear factor I B (NFIB) were detected using quantitative real-time PCR and Western blot assays. In-vitro experiments were conducted by using cell counting kit-8, cell colony formation, 5-ethynyl-2'-deoxyuridine, flow cytometry, and transwell assays, respectively. In-vivo assay was performed using murine xenograft model. The binding interaction between miR-942-5p and circ-PIP5K1A or NFIB was confirmed using dual-luciferase reporter assay. Exosomes were obtained from culture media by the use of commercial kits and qualified by transmission electron microscopy and Western blot. Circ-PIP5K1A was highly expressed in DDP-resistant OC tissues and cells. Circ-PIP5K1A knockdown could constrain the proliferation, migration, and invasion, as well as increase apoptosis and sensitivity to DDP in DDP-resistant OC cells. Mechanistically, circ-PIP5K1A acted as a sponge for miR-942-5p to positively regulate NFIB expression. Moreover, rescue experiments demonstrated that the anticancer and DDP sensitization effects caused by circ-PIP5K1A silencing in DDP-resistant OC cells were achieved through the miR-942-5p/NFIB axis. Importantly, circ-PIP5K1A silencing enhanced DDP efficacy and impeded tumor growth in OC in vivo . Additionally, we also found that circ-PIP5K1A was packaged into exosomes and could be internalized by surrounding cells. Circ-PIP5K1A knockdown reduced the resistance to DDP in OC via regulating miR-942-5p/NFIB axis. Besides that, circ-PIP5K1A was packaged into exosomes and exosomal circ-SKA3 could mediate intercellular communication between OC cells. These findings provided a promising therapeutic target for OC.

Estimating the Risk for Secondary Cancer After Targeted α-Therapy with 211At Intraperitoneal Radioimmunotherapy

Intraperitoneal ²¹¹At-based targeted α-therapy (TAT) may hold great promise as an adjuvant therapy after surgery and chemotherapy in epithelial ovarian cancer to eradicate any remaining undetectable disease. This implies that it will also be delivered to patients possibly already cured by the primary treatment. An estimate of long-term risks is therefore sought to determine whether the treatment is justified. Methods: Baseline data for risk estimates of α-particle irradiation were collected from published studies on excess cancer induction and mortality for subjects exposed to either ²²⁴Ra treatments or Thorotrast contrast agent (25% ThO₂ colloid, containing ²³²Th). Organ dosimetry for ²²⁴Ra and Thorotrast irradiation were taken from the literature. These organ-specific risks were then applied to our previously reported dosimetry for intraperitoneal ²¹¹At-TAT patients. Results: Risk could be estimated for 10 different organ or organ groups. The calculated excess relative risk per gray (ERR/Gy) could be sorted into 2 groups. The lower-ERR/Gy group, ranging up to a value of approximately 5, included trachea, bronchus, and lung, at 0.52 (95% CI, 0.21-0.82); stomach, at 1.4 (95% CI, -5.0-7.9); lymphoid and hematopoietic system, at 2.17 (95% CI, 1.7-2.7); bone and articular cartilage, at 2.6 (95% CI, 2.0-3.3); breast, at 3.45 (95% CI, -10-17); and colon, at 4.5 (95% CI, -3.5-13). The higher-ERR/Gy group, ranging from approximately 10 to 15, included urinary bladder, at 10.1 (95% CI, 1.4-23); liver, at 14.2 (95% CI, 13-16); kidney, at 14.9 (95% CI, 3.9-26); and lip, oral cavity, and pharynx, at 15.20 (95% CI, 2.73-27.63). Applying a typical candidate patient (female, age 65 y) and correcting for the reference population mortality rate, the total estimated excess mortality for an intraperitoneal ²¹¹At-monoclonal antibody treatment amounted to 1.13 per 100 treated. More than half this excess originated from urinary bladder and kidney, 0.29 and 0.34, respectively. Depending on various adjustments in calculation and assumptions on competing risks, excess mortality could range from 0.11 to 1.84 per 100 treated. Conclusion: Published epidemiologic data on lifelong detriment after α-particle irradiation and its dosimetry allowed calculations to estimate the risk for secondary cancer after ²¹¹At-based intraperitoneal TAT. Measures to reduce dose to the urinary organs may further decrease the estimated relative low risk for secondary cancer from ²¹¹At-monoclonal antibody-based intraperitoneal TAT.

UBE2T regulates epithelial–mesenchymal transition through the PI3K-AKT pathway and plays a carcinogenic role in ovarian cancer

Background

Ubiquitin-binding enzyme E2T (UBE2T), a member of the E2 family of the ubiquitin–proteasome pathway, is associated with tumorigenesis of varioustumours; however, its role and mechanism in ovarian cancer remain unclear.

Results

Our study revealed that UBE2T is highly expressed in ovarian cancer; this high expression was closely related to poor prognosis. Immunohistochemistry was used to validate the high expression of UBE2T in ovarian cancer. This is the first study to demonstrate that UBE2T expression is higher in ovarian cancer with BRCA mutation. Moreover, we demonstrated that UBE2T gene silencing significantly inhibited ovarian cancer cell proliferation and invasion. The epithelial–mesenchymal transition (EMT) of ovarian cancer cells and phosphatidylinositol 3 kinase/protein kinase B (PI3K-AKT) pathway were significantly inhibited. Adding the mechanistic target of rapamycin activator MHY1485 activated the PI3K-AKT pathway and significantly restored the proliferative and invasive ability of ovarian cancer cells. Furthermore, a tumorigenesis experiment in nude mice revealed that tumour growth on mice body surface and tumour tissue EMT were significantly inhibited after UBE2T gene silencing.

Conclusions

This study demonstrated that UBE2T regulates EMT via the PI3K-AKT pathway and plays a carcinogenic role in ovarian cancer. Moreover, UBE2T may interact with BRCA to affect ovarian cancer occurrence and development. Hence, UBE2T may be a valuable novel biomarker for the early diagnosis and prognosis and treatment of ovarian cancer. Further, UBE2T inhibition may be effective for treating ovarian cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-022-01034-9.

ML323 suppresses the progression of ovarian cancer via regulating USP1-mediated cell cycle

Background: Ubiquitin specific protease 1 (USP1) tightly correlates with poor prognosis of multiple cancers. However, whether USP1 underlies ovarian cancer (OV) progression remains unclarified.

Methods: First, GSEA strategy and WGCNA analysis were used to screen for anti-ovarian cancer drugs and furthern optimal module, respectively. In addition, functional enrichments of module genes were realized by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Kaplan-Meier was then employed to analyze the prognostic impact of USP1 expression on OV patients. Cell proliferation and cell cycle assays were used to confirm biological functions of USP1 in the final.

Results: Through the forementioned methods, we obtained five candidate drugs against OV from 353 anticancer drugs, and proposed ML323 as a novel anti-OV drug. As our hypothesized, ML323 significantly inhibited the proliferation of OV cells. Combined with WGCNA and KEGG analysis, the turquoise module was related to ML323, together with cell cycle. USP1 was subsequently identified as a target of ML323 and according to the TCGA database, USP1 negatively correlated with prognosis in OV, and its reduction and ML323-treatment both inhibited the proliferation of OV cells, blocking the S phase of cell cycle in vitro.

Conclusion: Taken together, ML323 exerts its inhibitory effect on the proliferation of OV cells by targeting USP1-regulated cell cycle, providing a therapeutical strategy and potential target against OV.

Clinico-pathologic characteristics and prognostic factors of ovarian carcinoma with different histologic subtypes - A benchmark analysis of 482 cases

PURPOSE

Ovarian carcinomas (OCX) have traditionally been thought to arise from the ovarian surface epithelium. However, recent (immuno-) histopathological and molecular analyses suggest that OCX consist of morphological subtypes with different epidemiologic features and a varying prognosis.

METHODS

The data of 482 OCX from the Clinical Cancer Registry of Leipzig who were surgically treated between 2000 and 2019 and were evaluated regarding incidence, clinico-pathologic characteristics and prognostic factors. Cases were separated into high-grade and non-high-grade serous tumors. Both groups were analyzed regarding the tumor stage, lymph node involvement, site of origin and prognosis.

RESULTS

The overall incidence for OCX was 17.9. The most common histological subtype was high-grade serous OCX (57.9%; 279/482). Patients with high-grade were significantly older than those with a non-high-grade serous OCX (63.9 versus 58.5 years; p < 0.001), more frequently diagnosed at an advanced stage >pT3 (78.5% (219/279) versus 42.8% (87/203); p < 0.001) and showed a 2.4-fold higher frequency of lymph node metastases (53.4% vs. 21.2%; p < 0.02) with a 4.6-fold higher rate of > 1 cm metastatic deposits (pN1b) within the lymph nodes (14.8% vs. 4.6%; p < 0.02). Irrespective of tumor stage and morphological subtype, the 1- and 5-year overall survival (OAS) was 72.9% and 40.8%, respectively. Patients with high-grade serous OCX showed a shorter 5-year OAS compared to non-high-grade serous OCX (34.1% vs. 57.0%; p 0.001). This association was reproducible in patients with an advanced tumor stage irrespective of the histopathologic tumor type serous OCX (pT3: 32.4% vs. pT1: 75.1%; p 0.001) as well as within high-grade (pT3: 28.7% vs. pT1: 55.5%; p = 0.003) and non-high-grade serous OCX (pT3: 43.0% vs. 80.0%; p 0.001). There were no differences in OAS depending on the site of origin (fallopian tube, ovary, peritoneum) within the two histologic subgroups.

CONCLUSION

OCX cases from a single institution with uniform surgical treatment and a standardized histopathological workup were evaluated. The poor prognostic outcome of patients with high-grade serous compared non-high-grade serous OCX as well as an advanced stage of the disease was confirmed. This study demonstrates for the first time that the histopathological distinction into high-grade serous and non-high-grade serous tumors may be much more prognostically relevant than the site of origin.

RP5-1148A21.3 (lncRP5) exerts oncogenic function in human ovarian carcinoma

Ovarian cancer (OC) is a fatal gynecological malignancy that is difficult to diagnose at early stages. Various long non-coding RNAs (lncRNAs) are aberrantly expressed in OC and exert regulatory effects on OC; however, the underlying mechanism requires in-depth investigation. This work is designed to explore the molecular regulatory axis of a newly identified lncRNA in OC, that is, lncRNA RP5-1148A21.3 (lncRP5). RT-qPCR shows lncRP5 is significantly upregulated in OC patients and cell lines, and it is mainly located in the cytoplasm of OC cells. The results of CCK-8, colony formation, and transwell assays demonstrate that overexpression of lncRP5 greatly contributes to malignant behaviors of OC cells, while inhibition of lncRP5 shows the opposite effects. Moreover, the binding relationship between lncRP5 and miR-545-5p is predicted by bioinformatics and is further verified by luciferase assay. Functionally, the regulatory effects of lncRP5 and miR-545-3p are negatively related; miR-545-5p serves as a tumor suppressor in OC. Further studies demonstrate that PTP4A1 is the target gene of miR-545-5p. Overexpression of PTP4A1 abrogates the inhibitory function of miR-545-5p on OC cell growth and metastasis. The lncRP5/miR-545-5p/PTP4A1 axis is subsequently demonstrated in vivo, and knockdown of lncRP5 notably inhibits tumor growth. This study provides a novel regulatory mechanism of OC, which may contribute to the diagnosis and therapy of OC.

Silencing of SBF2-AS1 inhibits cell growth and invasion by sponging microRNA-338-3p in serous ovarian carcinoma

Long noncoding RNA SET-binding factor 2 (SBF2) antisense RNA 1 (AS1) is associated with the growth and metastasis of multiple cancer types, but its biological roles in serous ovarian carcinoma (SOC) remain unclear. In this study, the aberrant upregulation of SBF2-AS1 is detected in SOC after analysis of differentially expressed genes between SOC tissues and normal fallopian tubes from the public Gene Expression Omnibus (GEO) database. We determine that knockdown of SBF2-AS1 inhibits SOC cell proliferation and invasion by sponging miR-338-3p. MiR-338-3p acts as a tumor suppressor in SOC, and E26 transformation specific-1 (ETS1) is identified as a potential target of miR-338-3p regulation. Furthermore, SBF2-AS1 could modulate ETS1 by operating as a competing endogenous RNA for miR-338-3p. This finding elucidates a new mechanism for SBF2-AS1 in SOC development and provides a potential target for SOC therapeutic intervention.

Identification of Prognostic Biomarkers Among FAM83 Family Genes in Human Ovarian Cancer Through Bioinformatic Analysis and Experimental Verification

Purpose

Family with sequence similarity 83 (FAM83) is a newly discovered oncogene family, and the members of which can affect the prognosis of patients with malignant tumors via various mechanisms. However, the functions and molecular mechanisms of FAM83 genes in ovarian cancer (OC) have not yet been investigated. This study aimed to explore the clinical significance and prognostic value of FAM83 genes in OC.

Materials and Methods

We used a series of bioinformatics databases (Oncomine, GEPIA, cBioPortal, Kaplan–Meier plotter, DAVID and TIMER) to investigate the expression status, prognostic value, genetic alteration and biological function of all eight FAM83 genes in OC. In addition, a tissue microarray cohort (TMA) comprising 99 ovarian tumor tissues and 19 normal ovarian tissues was used to validate the protein expression and clinicopathological significance of FAM83H.

Results

Several datasets demonstrated the mRNA levels of FAM83A/D/E/F/H were significantly higher in OC compared with that in normal tissue. Moreover, the upregulation of FAM83D/H has been mutually confirmed in the Oncomine and GEPIA datasets. Kaplan–Meier survival analysis indicated that the FAM83D/H upregulation could predict poor prognosis of OC patients who had shorter overall survival (OS) and progression-free survival (PFS). In addition, cBioportal analysis indicated that the genetic alterations of FAM83 genes might affect the survival outcomes of patients with OC. Furthermore, KEGG analysis suggested that FAM83D/H are involved in the progression of OC through the cell cycle signaling pathway, and they had significant co-expression relationship with cell cycle-related genes. Finally, immunohistochemistry analysis confirmed the high expression of FAM83H protein in OC tissue, suggesting that its expression is positively correlated with the FIGO stage and pathological subtype of OC.

Conclusion

This study elucidated the expression status and prognostic value of FAM83 genes in OC and identified that FAM83D/H might be potential targets for the prognostic monitoring and targeted therapy of OC.

LINC00852 promotes the proliferation and invasion of ovarian cancer cells by competitively binding with miR-140-3p to regulate AGTR1 expression

Background

Dysregulation of long non-coding RNAs (lncRNAs) has been identified in ovarian cancer. However, the expression and biological functions of LINC00852 in ovarian cancer are not understood.

Methods

The expressions of LINC00852, miR-140-3p and AGTR1 mRNA in ovarian cancer tissues and cells were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay. Gain- and loss-of-function assays were performed to explore the biological functions of LINC00852 and miR-140-3p in the progression of ovarian cancer in vitro. The bindings between LINC00852 and miR-140-3p were confirmed by luciferase reporter gene assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay.

Results

We found that LINC00852 expression was significantly up-regulated in ovarian cancer tissues and cells, whereas miR-140-3p expression was significantly down-regulated in ovarian cancer tissues. Functionally, LINC00852 knockdown inhibited the viability, proliferation and invasion of ovarian cancer cells, and promoted the apoptosis of ovarian cancer cells. Further investigation showed that LINC00852 interacted with miR-140-3p, and miR-140-3p overexpression suppressed the viability, proliferation and invasion of ovarian cancer cells. In addition, miR-140-3p interacted with AGTR1 and negatively regulated its level in ovarian cancer cells. Mechanistically, we found that LINC00852 acted as a ceRNA of miR-140-3p to promote AGTR1 expression and activate MEK/ERK/STAT3 pathway. Finally, LINC00852 knockdown inhibited the growth and invasion ovarian cancer in vivo.

Conclusion

LINC00852/miR-140-3p/AGTR1 is an important pathway to promote the proliferation and invasion of ovarian cancer.

RHPN1‑AS1 promotes ovarian carcinogenesis by sponging miR‑6884‑5p thus releasing TOP2A mRNA

Ovarian cancer, a severe lethal gynecological malignancy, is characterized by both high morbidity and mortality. Long noncoding RNAs (lncRNAs) have recently caused extensive concern due to their regulatory function in various human tumors. There are a mounting number of lncRNAs that are in extreme need of research, serving as biomarkers for diagnosis and therapy for ovarian cancer. In the present study, RT-qPCR was employed to detect how Rhophilin Rho GTPase binding protein 1 antisense RNA1 (RHPN1-AS1), miR-6884-5p and DNA topoisomerase IIα (TOP2A) are expressed in ovarian cancer tissues or cell lines. BrdU, MTT, colony formation and cell adhesion assays, caspase-3 activity, flow cytometry and wound healing assay were employed to assess cell proliferation, viability, colony number, adhesion, apoptosis and migration in ovarian cancer, respectively. RHPN1-AS1 was determined to be enriched in ovarian cancer tissues and cell lines. Silencing of RHPN1-AS1 was reported to increase cell apoptosis and impair cell proliferation, viability, colony number, adhesion and migration in vitro. Furthermore, RHPN1-AS1 was able to sponge miR-6884-5p which directly targets TOP2A in ovarian cancer. Notably, silencing of RHPN1-AS1 functionally reversed the oncogenic effect induced by the miR-6884-5p inhibitor, while the miR-6884-5p inhibitor markedly restored the inhibition of ovarian carcinogenesis modulated by silencing TOP2A in ovarian cancer. RHPN1-AS1 was found to promote ovarian carcinogenesis via sponging miR-6884-5p thus releasing TOP2A, and RHPN1-AS1 may act as a promising biomarker for the prognosis and therapy of ovarian cancer.

SP1-induced lncRNA DANCR contributes to proliferation and invasion of ovarian cancer

Transcription factor SP1 could manipulate pathways involved in ovarian cancer progression. LncRNAs are involved in SP1-mediated tumorigenesis. LncRNA DANCR could promote metastasis of ovarian cancer. However, the regulatory function and involvement of SP1-induced lncRNA DANCR in ovarian cancer remain elusive. Data from this study showed that SP1 was up-regulated in ovarian cancer tissues and cells (CAOV3, SKOV3, A2780), and SP1 could bind to the promoter region of DANCR through chromatin immunoprecipitation and leuciferase activity assays. Therefore, DANCR was transcriptionally induced by SP1 in ovarian cancer tissues and cells (CAOV3, SKOV3, A2780). Functionally, reduced expression of DANCR suppressed cell viability, migration and invasion of CAOV3, while enhanced DANCR expression contributed to SKOV3 growth. Over-expression of SP1 reversed the suppressive effects of DANCR interference on ovarian cancer progression. In conclusion, SP1-induced DANCR contributed to oncogenic potential of ovarian cancer, suggesting a promising therapeutic target for ovarian cancer.

Increased Expression of UBE2T Predicting Poor Survival of Epithelial Ovarian Cancer: Based on Comprehensive Analysis of UBE2s, Clinical Samples, and the GEO Database

Ubiquitin-conjugating enzymes E2 (UBE2) have been reported in the microenvironment of various malignant tumors, but their correlation with ovarian cancer (OC) remains elusive. This study aimed to systematically analyze the expression patterns, prognostic value, genetic variation, and biological functions of 12 members of the UBE2 gene family in OC through the Oncomine, Gene Expression Profiling Interactive Analysis (GEPIA), Kaplan-Meier plotter, cBioPortal, and Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) databases, respectively. We found that the mRNA levels of UBE2C, UBE2N, UBE2S, and UBE2T were significantly upregulated in OC compared with those in normal ovarian tissue. In patients with serous ovarian cancer (SOC), UBE2A, UBE2B, UBE2C, UBE2G, UBE2R2, and UBE2T upregulation were associated with poor overall survival. Moreover, UBE2A, UBE2N, UBE2R2, and UBE2T upregulation and UBE2G downregulation were associated with poor progression-free survival. UBE2T exhibited a strong correlation with OC and was thus further examined. We found that UBE2T has a high diagnostic accuracy (area under the receiver operating characteristic curve = 0.969) in epithelial ovarian cancer (EOC). Immunohistochemical assays and the Gene Expression Omnibus (GEO) database revealed that UBE2T was significantly upregulated in EOC compared with that in borderline tumors, benign tumors, and normal ovarian tissues, and its high expression was associated with poor prognosis. The Cox model showed that UBE2T upregulation was an independent risk factor affecting the prognosis of EOC and SOC. Furthermore, UBE2T was associated with specific immune cells and was mainly involved in cell cycle-related events. Genomic analysis showed that TP53 and TTN mutations were associated with UBE2T expression. Gene copy number amplification and hypomethylation may be responsible for UBE2T upregulation in OC. In conclusion, UBE2 family members may play a role in the development of OC. Specifically, UBE2T could serve as a new prognostic marker and therapeutic target for this disease. (IRB Approval No. 2020PS533K).

Long Non-Coding RNA USP2-AS1 Accelerates Cell Proliferation and Migration in Ovarian Cancer by Sponging miR-520d-3p and Up-Regulating KIAA1522

Background

Ovarian cancer is one of the malignant tumors attacking the female reproductive system. Currently, increasing studies have clearly determined the importance of long non-coding RNAs (lncRNAs) in various human cancers including ovarian cancer. However, the role and in-depth mechanism of ubiquitin specific peptidase 2 antisense RNA 1 (USP2-AS1) in ovarian cancer have been not reported yet.

Purpose

We were absorbed into exploring the character of USP2-AS1 in ovarian cancer.

Methods

RT-qPCR analysis reflected gene expression. The GEPIA database provided further evidences, and bioinformatics tools analyzed the potential molecules downstream USP2-AS1 in ovarian cancer. The changes on ovarian cancer cellular functions were assessed via EdU, TUNEL, JC-1 and transwell assays. RNA pull down, RIP and luciferase reporter assays estimated molecule interactions.

Results

USP2-AS1 was obviously up-regulated in ovarian cancer tissues and cell lines. Inhibiting USP2-AS1 had anti-proliferation, pro-apoptosis, and anti-migration effects on ovarian cancer cells. Furthermore, we confirmed that USP2-AS1 sequestered miR-520d-3p to enhance KIAA1522. In addition, miR-520d-3p silence reversed the effect of depleted USP2-AS1 on ovarian cancer cellular behaviors, while such reversion was then abolished by KIAA1522 knockdown.

Conclusion

USP2-AS1 facilitated ovarian cancer progression via miR-520d-3p/KIAA1522 axis, implying USP2-AS1 as a new perspective for the treatment of ovarian cancer.

High-grade serous peritoneal cancer follows a high stromal response signature and shows worse outcome than ovarian cancer

In the era of personalized medicine, where transition from organ‐based to individualized genetic diagnosis takes place, the tailoring of treatment in cancer becomes increasingly important. This is particularly true for high‐grade, advanced FIGO stage serous adenocarcinomas of the ovary (OC), fallopian tube (TC), and peritoneum (PC), which are currently all treated identically. We analyzed three independent patient cohorts using histopathologically classified diagnosis and various molecular approaches (transcriptomics, immunohistochemistry, next‐generation sequencing, fluorescent and chromogenic in situ hybridization). Using multivariate Cox regression model, we found that PC is more aggressive compared with advanced‐stage OC independent of residual disease as shown by an earlier relapse‐free survival in two large cohorts (HR: 2.63, CI: 1.59–4.37, P < 0.001, and HR: 1.66, CI: 1.04–2.63, P < 0.033). In line with these findings, transcriptomic data revealed differentially expressed gene signatures identifying PC as high stromal response tumors. The third independent cohort (n = 4054) showed a distinction between these cancer types for markers suggested to be predictive for chemotherapy drug response. Our findings add additional evidence that ovarian and peritoneal cancers are epidemiologically and molecularly distinct diseases. Moreover, our data also suggest consideration of the tumor‐sampling site for future diagnosis and treatment decisions.

Increase of fallopian tube and decrease of ovarian carcinoma: fact or fake?

PURPOSE

Accurate disease classification is fundamental for the selection of the treatment approach, prognostication, selection of clinical trials and for research purposes in routine clinical practice. Extrauterine high-grade serous carcinoma (HG-SC) may arise from the ovary, the fallopian tube and rarely from the peritoneal surface epithelium. Regardless of its origin, the vast majority of patients with HG-SC share clinical symptoms, present with advanced stage disease and suffer from a poor prognosis. Recent data suggest that there is an increasing incidence of HG-SC arising from the fallopian tube.

METHODS

Data from the Clinical Cancer Registry of Leipzig of surgically treated non-uterine pelvic carcinomas were analyzed regarding their sites of origin. Depending on the histology, cases were separated into high-grade serous and non-high-grade serous tumors. Based on different approaches in the assessment of the site of origin, three distinct time periods were defined. The frequency of the specific sites of origin was compared to the different time periods and histologic subtypes.

RESULTS

The majority of cases (57.9%; 279/482) were high-grade serous carcinomas, 42.1% of the cases presented with endometrioid, clear cell or mucinous histology. Overall, a 1.7-fold decrease of carcinomas with ovarian origin, paralleled by a 10.3-fold increase of tubal carcinomas was noted between 2000 and 2019. Based on the histopathological subtype, there was a 2.1-fold decrease of ovarian and a 7.1-fold increase of tubal carcinomas in patients with HG-SC. In non-high-grade serous tumors, the frequency of the different sites of origin did not change. 83.7% of tumors with non-high-grade serous histology originated from the ovary, whereas 86.8% of the carcinomas with tubal origin were of high-grade serous histology.

CONCLUSION

The present and published data of non-uterine pelvic cancers may suggest an increase of tubal and decrease of ovarian carcinomas. However, there is rising morphologic and molecular evidence that non-uterine HG-SC actually arise from the fallopian tubes via its precursor STIC instead of from the ovary. This evidence has had an impact on the handling and reporting of non-uterine surgical specimens and its definition of the site assessment. In conclusion, the increasing frequency of tubal carcinomas and the associated decrease in ovarian cancer appears to be due to the reclassification of tumors previously classified as ovarian and greater emphasis on examining the resection specimens of non-uterine pelvic carcinomas.

Long non-coding RNA LINC00858 aggravates the oncogenic phenotypes of ovarian cancer cells through miR-134-5p/RAD18 signaling

PURPOSE

Ovarian cancer is a common gynecological cancer. Herein, we focused on the function and probable mechanisms of LINC00858 in ovarian cancer.

METHODS

Real-time quantitative polymerase chain reaction (RT-qPCR) was employed for detecting the expression of LINC00858, miR-134-5p and RAD18 E3 ubiquitin protein ligase (RAD18). Cell proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) and apoptosis were detected by cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), transwell, terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) and western bolt experiments, as appropriate. Interplays between LINC00858, miR-134-5p and RAD18 were detected by RNA immunoprecipitation (RIP), RNA pull down and luciferase reporter assays.

RESULTS

LINC00858 were up-regulated in ovarian cancer tissues and cells, and its expression was elevated in advanced samples compared to early ones. Knocking down LINC00858 inhibited cell proliferation, motility and EMT, but accelerated cell apoptosis in ovarian cancer. Moreover, could be sponged by LINC00858 sponged miR-134-5p to enhance RAD18 expression in ovarian cancer. Also, silenced RAD18 could also restrain oncogenic behaviors of ovarian cancer cells. Rescue experiments showed that overexpressing RAD18 reversed the effects caused by knocking down LINC00858 on cellular processes.

CONCLUSION

LINC00858 sequestered miR-134-5p to elevate RAD18 expression, resulting in aggravated development of ovarian cancer. This might provide promising targets for treating patients with ovarian cancer.

YY1-induced lncRNA DSCR8 promotes the progression of ovarian cancer via miR-3192-5p/YY1 axis

Ovarian cancer endangers the life of women worldwide. Plenty of lncRNAs have been found modulating the progression of ovarian cancer. Meanwhile, lncRNA DSCR8 (Down syndrome critical region 8) has been reported as an oncogene in hepatocellular carcinoma. In this study, we aimed to search the function of DSCR8 in ovarian cancer. qRT-PCR analysis assessed the expression of DSCR8 in ovarian cancer cells. EdU assay and colony formation assay was used to test cell proliferation. Flow cytometry analysis and TUNEL assay were conducted to investigate cell apoptosis. Wound healing assay and transwell invasion assay assessed cell migration and invasion. DSCR8 was significantly up-regulated in ovarian cancer cells. Inhibited DSCR8 could suppress the progression of ovarian cancer. Also, YY1 could activate the expression of DSCR8 in ovarian cancer cells. Meanwhile, DSCR8/miR-3192-5p/YY1 axis was identified in ovarian cancer cells. MiR-3192-5p could function as tumor suppresser in ovarian cancer cells. Furthermore, DSCR8 and YY1 (Yin Yang 1) transcription factor could play the regulatory network in ovarian cancer cells. In a word, YY1-induced lncRNA DSCR8 promotes the progression of ovarian cancer via miR-3192-5p/YY1 axis.

An integrated analysis reveals the oncogenic function of lncRNA LINC00511 in human ovarian cancer

Ovarian cancer is one of the most common female reproductive system malignancies worldwide. Recently, the aberrant long noncoding RNAs (lncRNAs) expression has been identified in multiple cancers. Emerging evidence has highlighted the critical roles of lncRNAs in carcinogenesis and tumor progression, including ovarian cancer. The objective of this study is to comprehensively analyze lncRNAs expression pattern, and explore their clinical significance and underlying mechanism in human ovarian cancer. In this study, we found hundreds of dysregulated lncRNAs in ovarian cancer by performing genome‐wide analysis using RNA sequencing data from Genotype‐Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) project, and three microarray datasets from Gene Expression Omnibus (GEO). Moreover, our results revealed that up‐ or down‐regulation of some lncRNAs expression in ovarian cancer is accompanied by their genomic loci copy number amplification or deletion. Importantly, some lncRNAs expression levels are significantly associated with ovarian cancer patients’ poor prognosis. Further experimental validation and mechanistic investigation indicate that LINC00511 exerts oncogenic function in ovarian cancer cells through interacting with EZH2 and repressing P21 expression. Taken together, the findings in the current study may provide a useful resource of novel ovarian cancer associated lncRNAs and potential diagnostic biomarker and therapeutic targets for ovarian cancer.

LncRNA PTAR promotes EMT and invasion-metastasis in serous ovarian cancer by competitively binding miR-101-3p to regulate ZEB1 expression

BACKGROUND

Ovarian cancer (OvCa) is one of the most common malignant diseases of the female reproductive system in the world. The majority of OvCa is diagnosed with metastasis in the abdominal cavity. Epithelial-to-mesenchymal transition (EMT) plays a key role in tumor cell metastasis. However, it is still unclear whether long non-coding RNA (lncRNA) is implicated in EMT and influences cell invasion and metastasis in OvCa.

RESULTS

In this study, using bioinformatcis analysis, we constructed a lncRNA-mediated competing endogenous RNA (ceRNA) network for mesenchymal OvCa and identified lncRNA AP000695.4, which we named pro-transition associated RNA (PTAR). PTAR was significantly up-regulated in the mesenchymal subtype samples compared with the epithelial subtype samples from the TCGA OvCa data sets. In addition, our study showed that PTAR expression was positively correlated with the expression level of ZEB1 in the mesenchymal OvCa samples. Meanwhile, we found that silencing miR-101 promoted cell migration, whereas the overexpression of miR-101 suppressed EMT and cell migration in OvCa cell lines through the regulation of ZEB1. Further analysis showed that enhanced expression of PTAR promoted EMT and metastasis through the regulation of miR-101, whereas silencing PTAR led to the attenuation of TGF-β1-induced tumorigenicity in ovarian cancer cells. Mechanistically, we found that PTAR acted as a ceRNA of miR-101, as forced expression of PTAR reduced the expression and activity of miR-101. More importantly, the knockdown of PTAR reduced tumorigenicity and metastasis in vivo.

CONCLUSIONS

Taken together, the results from our study highlight a role for the PTAR-miR-101-ZEB1 axis in OvCa, which offers novel strategies for the prevention of metastasis in OvCa.

Trends in the incidence of serous fallopian tube, ovarian, and peritoneal cancer in the US

OBJECTIVE

To identify the trends in incidence of serous fallopian tube, ovarian, and peritoneal epithelial cancers in the United States.

METHODS

Data was obtained from United States Cancer Statistics (USCS) from 2001 to 2014. All incidences are per 100,000 women. Analyses were performed using SEER*Stat and Joinpoint regression programs.

RESULTS

Of the 146,470 patients with serous cancers, 9381 (6.4%) were fallopian tube, 121,418 (82.9%) were ovarian, and 15,671 (10.7%) were primary peritoneal. The study period was divided from 2001 to 2005, 2006-2010, and 2011-2014, and there was an increase in fallopian tube incidence from 0.19 to 0.35 to 0.63, with a corresponding decrease in ovarian incidence from 5.31 to 5.08 to 4.86. There was no significant change in peritoneal cancers from 0.64 to 0.69 to 0.62. The age-specific peak incidence of fallopian tube cancer was younger at age 70-74, compared to ovarian and peritoneal cancer at age 75-79. Further, the incidence of serous fallopian tube cancer was highest in Whites at 0.42, compared to Blacks at 0.24, Hispanics at 0.27, and Asians at 0.28.

CONCLUSION

From 2001 to 2014, the diagnosis of serous fallopian tube cancer increased fourfold with a corresponding decrease in ovarian cancer. The peak incidence of tubal cancer was 70-74years with an increased incidence in Whites.

Tissue glycomics distinguish tumour sites in women with advanced serous adenocarcinoma

In the era of precision medicine, the tailoring of cancer treatment is increasingly important as we transition from organ‐based diagnosis towards a more comprehensive and patient‐centric molecular diagnosis. This is particularly the case for high‐grade serous adenocarcinomas of the ovary and peritoneum, which are commonly diagnosed at an advanced stage, and collectively treated and managed similarly. We characterized the N‐ and O‐glycome of serous ovarian (OC) and peritoneal cancer (PC) tissues using PGC‐LC‐ESI‐IT‐MS/MS profiling and validated the discriminatory glycans and their corresponding glyco‐gene expression levels using cell lines and transcriptomic data from 232 patients. Overall, the N‐ and O‐glycan repertoires of both cancer types were found to comprise mostly of α2,6‐sialylated glycan structures, with the majority of N‐glycans displaying the biantennary mono‐ and disialylation as well as bisecting‐type biantennary glycans. The MS profiling by PGC‐LC also revealed several glycan structural isomers that corresponded to LacdiNAc‐type (GalNAcβ1‐4GlcNAc) motifs that were unique to the serous ovarian cancers and that correlated with elevated gene expression of B4GALNT3 and B4GALNT4 in patients with serous cancer. Statistical evaluation of the discriminatory glycans also revealed 13 N‐ and 3 O‐glycans (P < 0.05) that significantly discriminated tumour‐sampling sites, with LacdiNAc‐type N‐glycans (m/z 1205.0²⁻ and m/z 1059.4²⁻) being associated with ovarian‐derived cancer tissue and bisecting GlcNAc‐type (m/z 994.9²⁻) and branched N‐glycans (m/z 1294.0²⁻ and m/z 1148.4²⁻) upregulated at the metastatic sites. Hence, we demonstrate for the first time that OC and PC display distinct molecular signatures at both their glycomic and transcriptomic levels. These signatures may have potential utility for the development of accurate diagnosis and personalized treatments.