Ability Of Ovarian Cancer Cells Research Articles

FOXA1 can be modulated by HDAC3 in the progression of epithelial ovarian carcinoma

FOXA1 is associated with malignant tumors, but the function of FOXA1 in EOC is unclear. HDAC3 can influence the proliferation, migration and invasion ability of EOC. In this study, we wanted to explore the function of FOXA1 in ovarian cancer and the relationship between HDAC3 and FOXA1.The expression of HDAC3 and FOXA1 was detected by immunohistochemical staining of primary lesions from 127 epithelial ovarian carcinoma patients. A proliferation assay, a Transwell assay, an apoptosis assay and animal experiments were used to assess the proliferation, invasion and apoptosis abilities of ovarian cancer cells before and after transfection with FOXA1. The relevance of the in vitro findings was confirmed in xenografts. The H-scores for FOXA1 and HDAC3 staining in FIGO stage III-IV were noticeably higher and predicted adverse clinical outcomes in patients with ovarian cancer. The expression level of HDAC3 was significantly correlated with the expression level of FOXA1. Invasion, proliferation and apoptosis capacity and tumor formation were decreased in the FOXA1-knockdown cells. Experiments in xenografts confirmed that HDAC3 mediated tumor formation. In conclusion, FOXA1 can be modulated by HDAC3 through the Wnt/β-catenin signaling pathway, and FOXA1 plays essential roles in the proliferation, apoptosis and invasion of EOC cell lines and xenograft experiments.

Effect of 1α,25(OH)2D3-Treated M1 and M2 Macrophages on Cell Proliferation and Migration Ability in Ovarian Cancer

The biological active form of vitamin D3, 1α,25-dehydroxyvitamin D3 [1α,25(OH)2D3], exerts pleiotropic effects including bone mineralization, anti-tumor, as well as immunomodulator. This study aimed to explore the potential impact of 1α,25(OH)2D3 on tumor-associated macrophages (TAMs) infiltration in ovarian cancer. Firstly, human monocytic THP-1 cells were differentiated into macrophages (M0) in the presence of phorbol 12-myristate 13-acetate (PMA). In Vivo, 1α,25(OH)2D3 not only reversed the polarization of M2 macrophages, but also decreased the proliferation and migration abilities of ovarian cancer cells induced by M2 macrophages supernatant. Furthermore, 1α,25(OH)2D3 dramatically decreased the secretion of TGF-β1 and MMP-9 in M2 macrophages. However, no significant effect was observed in 1α,25(OH)2D3 treated M1 macrophages. In Vivo, vitamin D3 had an inhibitive effect of 1α,25(OH)2D3-treated M2 macrophages on tumorigenesis. In addition, we conducted the association of TAMs with the poor prognosis of patients with ovarian cancer by meta-analysis, which suggested the higher proportion of M2 macrophages was related to the poorer prognosis in ovarian cancer. Collectively, these results identified distinct roles of 1α,25(OH)2D3 treated M1 and M2 macrophages on cell proliferation and migration abilities in ovarian cancer.

LncRNA SNHG14 Promotes Progression of Ovarian Cancer by Regulating miR-206 Expression

Objective: This study aimed to probe into the effect of LncRNA SNHG14 on ovarian cancer progression by regulating miR-206.Methods: Fifty-seven ovarian cancer (OC) patients who were treated in our hospital from December 2017 to December 2019 were collected as the research objects. During the operation, OC tissues and paracancerous tissues of patients were collected, and the effect of SNHG14 on OC tumor growth in nude mice was detected, and SNHG14 inhibitor was transfected into OC cells. The relative expression of SNHG14 in tissues and cells was detected by qRT-PCR, cell proliferation was testedvia CCK8, migration and invasion were detected through Transwell, apoptosis was assessedvia flow cytometry, and the targeted relationship between SNHG14 and miR-206 was detected by dual luciferase reporter gene.Results: SNHG14 is highly expressed in OC tissues, cells and nude mice. Down-regulating it can inhibit the biological ability of OC cells and inhibit the growth of nude mice tumors. It can directly target miR-206 to regulate CCND1 expression and promote OC progression.Conclusion: LncRNA SNHG14 can act as miR-206 sponge to regulate CCND1 expression downstream of miR-206 and promote OC progression.

The Stress-Inducible BCL2A1 Is Required for Ovarian Cancer Metastatic Progression in the Peritoneal Microenvironment.

Simple SummaryCancer metastasis is still the main cause of cancer-related mortality. Peritoneal metastases are the first presentation of advanced ovarian cancer, and metastatic cancer cells tend to disseminate trans-peritoneally in the peritoneal cavity. Hypoxia is a critical factor in governing transcoelomic metastases of ovarian cancer. Therefore, targeting hypoxia appears to be a promising approach to arrest cancer metastasis. In the present work, we identified that BCL2A1, a BCL2 family member, is significantly induced by hypoxia and other physiological stresses by NF-κB signaling and followed by a gradual degradation. The upregulated BLC2A1 has been shown to enhance ovarian cancer survival, tumor growth, and tumor dissemination by suppressing intrinsic cell apoptosis. These data indicate BCL2A1 is an early response factor in the stressed tumor microenvironment, and targeting BCL2A1 may be a potential therapeutic approach in eradicating peritoneal metastases of ovarian cancer.Emerging evidence indicates that hypoxia plays a critical role in governing the transcoelomic metastasis of ovarian cancer. Hence, targeting hypoxia may be a promising approach to prevent the metastasis of ovarian cancer. Here, we report that BCL2A1, a BCL2 family member, acts as a hypoxia-inducible gene for promoting tumor progression in ovarian cancer peritoneal metastases. We demonstrated that BCL2A1 was induced not only by hypoxia but also other physiological stresses through NF-κB signaling and then was gradually reduced by the ubiquitin-proteasome pathway in ascites-derived ovarian cancer cells. The upregulated BCL2A1 was frequently found in advanced metastatic ovarian cancer cells, suggesting its clinical relevance in ovarian cancer metastatic progression. Functionally, BCL2A1 enhanced the foci formation ability of ovarian cancer cells in a stress-conditioned medium, colony formation in an ex vivo omental tumor model, and tumor dissemination in vivo. Under stress conditions, BCL2A1 accumulated and colocalized with mitochondria to suppress intrinsic cell apoptosis by interacting with the BH3-only subfamily BCL2 members HRK/BAD/BID in ovarian cancer cells. These findings indicate that BCL2A1 is an early response factor that maintains the survival of ovarian cancer cells in the harsh tumor microenvironment.

Silencing ROR2 inhibits metastatic behavior of ovarian cancer cells

Objectives: Adhesion of migrating ovarian tumor cells to peritoneal mesothelial cells and their subsequent clearance of the mesothelial monolayer is a key early event in metastatic seeding of ovarian cancer. We sought to identify mediators of ovarian cancer adhesion and invasion contributing to this tumor-microenvironment interplay. Methods: To identify potential drivers of ovarian cancer adhesion and invasion, a multicellular assay incorporating tumor (epithelial ovarian cancer cells) and microenvironment (patient derived omental fibroblasts) was adapted to carry out a high throughput genetic screen using a human kinome siRNA library. Based on screen candidates, ROR2, a noncanonical Wnt receptor that binds Wnt5a, was identified. ROR2 expression was evaluated in primary patient derived ovarian cancer cells and in high grade ovarian cancer cell lines (ES2, A2780, OVCAR3, OVCAR5, OVCAR8, ID8Trp53-/-BRCA2-/-). Biologic roles of ROR2 as well as the therapeutic effect of ROR2 silencing were examined in vitro using a validated mesothelial cell clearance assay. We further examined the effect of ROR2 silencing on force generation by ovarian cancer cell spheroids using immunofluorescent staining of phospho-myosin light chain (pMLC). Results: ROR2 was found to be expressed at a protein level across established ovarian cancer cell lines as well as primary ovarian cancer cells from patient derived tumors. Analysis in multicellular assays demonstrated that ROR2 silencing with siRNA dramatically decreases mesothelial cell clearance by tumor cell spheroids when compared to control siNEG spheroids. This result was observed across multiple cell lines (ES2, OVCAR8, OVCAR5, and OVCAR3) (P Conclusions: ROR2 plays a critical role in mediating the ability of ovarian cancer cells to clear a mesothelial cell monolayer, a key step leading to metastasis in ovarian cancer. Mesothelial clearance has been demonstrated to be a force dependent process, and our data suggests that ROR2 may play a role in force generation by ovarian cancer spheroids. Understanding the factors driving prometastatic tumor-microenvironment interactions is critical to develop targeted therapeutics to block the spread of ovarian cancer. As ROR2 is an actionable target, further investigation of ROR2 targeting in ovarian cancer is needed as it may represent a novel treatment strategy.

Abstract 2384: Hypoxia-induced exosomal miR-376c-3p promotes metastatic potential of ovarian cancer cells

Abstract Background: Hypoxia significantly impacts cancer progressions, in various types of solid tumors including ovarian cancer. Exosomes (30-150nm) secreted from cells in the hypoxic tumor microenvironment play a critical role in cancer progression through transferring functional proteins, mRNAs, and miRNAs as mediators of intercellular communication. However, the underlying mechanisms how cancer exosomes induced by hypoxia regulate cancer progressions remain elusive. This study aims to assess the effect of exosomes secreted from hypoxic cancer cells on the metastatic ability of ovarian cancer cells. Methods: Two ovarian cancer cell lines, Kuramochi and SKOV-3, were used. Exosomes from cancer cells cultured under normoxic or hypoxic conditions (normoxic or hypoxic exosomes) were isolated using Exoquick-TC kit and identified by nanoparticle tracking analysis, transmission electron microscopy, and western blotting. BCA assay was done to evaluate the concentration of exosomes. Normoxic or hypoxic exosomes were treated on ovarian cancer cells. Cell migration and invasion abilities were examined by wound healing assay and MatriGel invasion assay respectively. Furthermore, miRNA sequencing was performed to explore the miRNA profiling of hypoxic and normoxic exosomes. Results: The size of exosomes was ranging from 52nm to 121nm (mean diameter = 85nm). The quantity of hypoxic exosomes was significantly more than that of normoxic exosomes. Hypoxic exosomes increased the migration and invasion ability of kuramochi and SKOV-3 cells. In addition, hypoxic exosomes treatment on ovarian cancer cells up-regulated the expression of MMP-2 and Snail-1 at the protein level. MiRNA sequencing showed that miR-376c-3p was significantly upregulated in hypoxic exosomes in both ovarian cancer cell lines. Moreover, miR376c-3p enhanced migration and invasion ability of ovarian cancer cells, validated by miR376c-3p inhibitor and mimics. Conclusions: Taken together, our study suggests that miR376c-3p transferred by hypoxic exosomes could promote the metastatic potential of ovarian cancer cells by inducing MMP-2 and Snail-1. Citation Format: HyunA Jo, Wenyu Wang. Hypoxia-induced exosomal miR-376c-3p promotes metastatic potential of ovarian cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2384.

Abstract 2366: Malignant ascites-derived extracellular vesicles promote metastasis of ovarian cancer by transferring miR-1246 and miR-1290

Abstract Background and purpose: Ovarian cancer is the most lethal gynecologic cancer in females worldwide. The high mortality rate is due primarily to the lack of early diagnosis strategies and the high rate of recurrence. Ascites is detected in over one-third of ovarian cancer patients at initial diagnosis and present in almost all the patients with recurrence. Extracellular vesicles (EVs) are double-membrane particles secreted by cells into extracellular space. EV-mediated intercellular communication in the tumor microenvironment is crucial in cancer progression. Additionally, EVs are present in various body fluids, serving as fine analytes for liquid biopsy. Our research is aimed to explore the role of malignant ascites-derived EVs in ovarian cancer metastasis and the underlying mechanisms focusing on the miRNA cargos. Methods: Patient-derived samples were collected from Seoul National University Hospital with the approval of the Institutional Review Board. EVs were isolated from ascites using the commercial kit and identified through transmission electron microscopy, nanoparticle tracking analysis and western blotting. Transwell assay was performed to investigate the effects of ascites-derived EVs on ovarian cancer cells. MiRNA sequencing was carried out in EVs derived from malignant ascites(n=10) and benign peritoneal fluids(n=9). Results: Malignant ascites-derived EVs were characterized as double-membrane particles sizing ranging from 30nm to 150nm with the expression of CD63 and CD81. Those EVs significantly promoted the invasion and migration ability of ovarian cancer cells. MiRNA sequencing data showed that 118 miRNAs were upregulated and 44 miRNAs were downregulated in the ascites-derived EVs compared with benign peritoneal fluid-derived EVs. Among those, miR-1246 and miR-1290 were the top two upregulated miRNAs, which were negatively associated with the overall survival of ovarian cancer patients. Moreover, miR-1246 and miR-1290 could enhance the invasion and migration ability through activating Wnt/β-catenin signaling pathway via binding to RAR-related orphan receptor alpha (RORα). Conclusion: Malignant ascites-derived EVs could facilitate the metastatic potential of ovarian cancer cells through transferring miR-1246 and miR-1290. Targeting miR-1246 and miR-1290 might be a promising therapeutic strategy in ovarian cancer treatment. Citation Format: Wenyu Wang, HyunA Jo, Yong Sang Song. Malignant ascites-derived extracellular vesicles promote metastasis of ovarian cancer by transferring miR-1246 and miR-1290 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2366.

PHGDH Is Upregulated at Translational Level and Implicated in Platin-Resistant in Ovarian Cancer Cells.

BackgroundPlatinum-based chemotherapy is the first line option for ovarian cancer. The development of resistance to such chemotherapy results in treatment failure, while the underlying mechanisms are poorly understood.MethodsClinical samples were collected from Shengjing Hospital of China Medical University. MTT assay was used to see the proliferation and chemoresistance of ovarian cancer cells. Transwell migration and Matrigel invasion assays was used to see the invasion ability of ovarian cancer cells. In addition, polysome profiling and tissue microarray and immunohistochemical staining were also used. The statistical significance of the difference was analyzed by ANOVA and post hoc Dunnett’s test.ResultsPHGDH is the first enzyme responsible for serine biosynthesis pathway. The current study demonstrated that PHGDH is upregulated in platin-resistant ovarian cancer cells and tissues at the protein level. Importantly, knockdown of PHGDH suppressed, while overexpression of PHGDH increased the survival upon cisplatin exposure, invasiveness and spheroid formation of ovarian cancer cells. The current study demonstrated that PHGDH translation was upregulated in platin-resistant ovarian cancer. In addition, our study provided evidence that LncRNA RMRP (RNA Component of Mitochondrial RNA Processing Endoribonuclease) was upregulated in platin-resistant ovarian cancer, which promoted enrichment of RNA binding protein DDX3X (DEAD-Box Helicase 3 X-Linked) on the PHGDH mRNA to promote its translation.ConclusionCollectively, the current study described that PHGDH was upregulated and conferred resistance of ovarian cancer cells to cisplatin, suggesting that cisplatin resistance could be overcome by targeting PHGDH. Our study also provided evidence that differential PHGDH protein expression was defined by its translation, and RNA binding protein DDX3X and LncRNA RMRP are regulators of its translation.

Metalloproteinases in Ovarian Cancer.

Proteases play a crucial role in the progression and metastasis of ovarian cancer. Pericellular protein degradation and fragmentation along with remodeling of the extracellular matrix (ECM) is accomplished by numerous proteases that are present in the ovarian tumor microenvironment. Several proteolytic processes have been linked to cancer progression, particularly those facilitated by the matrix metalloproteinase (MMP) family. These proteases have been linked to enhanced migratory ability, extracellular matrix breakdown, and development of support systems for tumors. Several studies have reported the direct involvement of MMPs with ovarian cancer, as well as their mechanisms of action in the tumor microenvironment. MMPs play a key role in upregulating transcription factors, as well as the breakdown of structural proteins like collagen. Proteolytic mechanisms have been shown to enhance the ability of ovarian cancer cells to migrate and adhere to secondary sites allowing for efficient metastasis. Furthermore, angiogenesis for tumor growth and development of metastatic implants is influenced by upregulation of certain proteases, including MMPs. While proteases are produced normally in vivo, they can be upregulated by cancer-associated mutations, tumor–microenvironment interaction, stress-induced catecholamine production, and age-related pathologies. This review outlines the important role of proteases throughout ovarian cancer progression and metastasis.

KAT6A, a novel regulator of β-catenin, promotes tumorigenicity and chemoresistance in ovarian cancer by acetylating COP1.

Background: Ovarian cancer is a fatal gynecologic malignancy that is found worldwide and exhibits an insidious onset and a lack of early warning symptoms. Despite ongoing studies, the mechanistic basis of the aggressive phenotypes of ovarian cancer remains unclear. Lysine acetyltransferase 6A (KAT6A) is a MYST-type histone acetyltransferase (HAT) enzyme identified as an oncogene in breast cancer, glioblastoma and leukemia. However, the specific functions of KAT6A in ovarian cancer remain unclear.Methods: Immunohistochemistry (IHC) staining and western blotting were performed to characterize KAT6A protein expression in ovarian cancer tissues and cell lines. The biological functions of KAT6A in ovarian cancer were evaluated by cell proliferation, wound healing and transwell invasion assays in vitro. Tumorigenesis and metastasis assays were performed in nude mice to detect the role of KAT6A in vivo. Mass spectrometry and immunoprecipitation assays were performed to detect the KAT6A-COP1 interaction. An in vivo ubiquitination assay was performed to determine the regulation of β-catenin by KAT6A.Results: In the present study, we revealed that KAT6A expression is upregulated in ovarian cancer and is associated with patient overall survival. Downregulation of KAT6A markedly inhibited the proliferation and migration abilities of ovarian cancer cells in vivo and in vitro. Additionally, the inhibition of KAT6A induced apoptosis and enhanced the sensitivity of ovarian cancer cells to cisplatin. Furthermore, KAT6A bound to and acetylated COP1 at K294. The acetylation of COP1 impaired COP1 function as an E3 ubiquitin ligase and led to the accumulation and enhanced activity of β-catenin.Conclusions: Our findings suggest that the KAT6A/COP1/β-catenin signaling axis plays a critical role in ovarian cancer progression and that targeting the KAT6A/COP1/β-catenin signaling axis could be a novel strategy for treating ovarian cancer.

LncRNA HOTAIR regulates anoikis-resistance capacity and spheroid formation of ovarian cancer cells by recruiting EZH2 and influencing H3K27 methylation

This study aims to investigate the role of the long non-coding RNA (lncRNA) HOX transcript antisense RNA (HOTAIR) in the regulation of anoikis resistance of ovarian cancer cells, a prerequisite for metastasis and chemoresistance in ovarian cancer cells. Ovarian cancer SKOV3 cells were cultured in an ultra-low attachment system to establish an anoikis model. The relationship between cellular anoikis capability and HOTAIR expression level was studied by flow cytometry and RT-PCR. The ability of spheroid formation, migration, and invasion of the suspended cells was assessed following the knockdown of HOTAIR expression. The expression of EZH2, H3K27me3, representative targets of EZH2, and anoikis-related biomarkers was also detected. An increase in the duration of suspension culture time rendered the SKOV3 cells anoikis-resistant with a significantly lower apoptotic rate compared to the adherent cells. HOTAIR expression in the suspension cells increased significantly, while that in the adherent cells did not. Following small interfering RNA (siRNA)-mediated knockdown of HOTAIR expression, the abilities of anoikis resistance, migration, and invasion decreased in the suspension cells. Knockdown of HOTAIR levels also reduced the spheroid forming ability of the tumor cells in continuous suspension cultures. Moreover, EZH2 expression correlated with HOTAIR expression, thus regulating the expression of miR-193a and DOK2 via introducing H3K27me3. Western blot analysis of anoikis-related markers showed that N-cadherin, ZEB1, and TWIST1 were downregulated following inhibition of HOTAIR, while E-cadherin and ErbB3 were upregulated. In conclusion, HOTAIR enhances the anoikis resistance and spheroid forming ability of ovarian cancer cells by recruiting EZH2 and influencing H3K27 methylation that may contribute to migration, invasion, and chemoresistance of ovarian cancer cells.

RSPO3 is a marker candidate for predicting tumor aggressiveness in ovarian cancer.

BackgroundOvarian cancer, a highly aggressive and heterogeneous gynecological malignancy that has long been difficult for physicians to identify and treat, requires more effective and precise molecular targets. R-spondin 3 (RSPO3) is a secreted protein that plays a tumorigenic role in several human cancers. However, the functional contribution and prognostic role of RSPO3 in ovarian cancer remain unclear.MethodsRSPO3 expression in ovarian cancer tissues was assessed using western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), and immunohistochemistry, and its relationships to clinicopathological parameters were investigated using the data of 179 ovarian cancer patients. RSPO3’s biological function was evaluated using Cell Counting Kit-8, colony formation, wound healing, and Matrigel transwell assay in RSPO3-knockdown and RSPO3-overexpression ovarian cancer cell lines SKOV3 and OVCAR3. The possible biological processes associated with RSPO3 were identified using functional enrichment analysis based on the transcriptome sequencing data from The Cancer Genome Atlas (TCGA) ovarian cancer cohort and our experimental cells, and further verified using western blotting and immunofluorescence in the ovarian cancer cell model.ResultsThe RSPO3 mRNA and protein levels were both upregulated in ovarian cancer tissues. High RSPO3 expression was correlated with lymphovascular space invasion (LVSI), lymph node metastasis, distant metastasis, and advanced tumor stage. Survival analysis showed that RSPO3 is an independent prognostic marker in ovarian cancer. Moreover, in vitro RSPO3 knockdown significantly inhibited the invasion ability of ovarian cancer cells, while overexpression significantly promoted it. Using transcriptome sequencing and pathway validation experiments, we demonstrated for the first time that RSPO3 promotes ovarian cancer invasiveness through activation of the PI3K/AKT pathway and modulation of epithelial-mesenchymal transition (EMT), while the common Wnt/β-catenin signaling pathway was not involved.ConclusionsRSPO3 plays a definite oncogenic role and promotes tumor aggressiveness in ovarian cancer, which may serve as a potential prognostic marker and therapeutic target for this disease.

Platinum-Induced Ubiquitination of Phosphorylated H2AX by RING1A Is Mediated by Replication Protein A in Ovarian Cancer.

Platinum resistance is a common occurrence in high-grade serous ovarian cancer and a major cause of ovarian cancer deaths. Platinum agents form DNA cross-links, which activate nucleotide excision repair (NER), Fanconi anemia, and homologous recombination repair (HRR) pathways. Chromatin modifications occur in the vicinity of DNA damage and play an integral role in the DNA damage response (DDR). Chromatin modifiers, including polycomb repressive complex 1 (PRC1) members, and chromatin structure are frequently dysregulated in ovarian cancer and can potentially contribute to platinum resistance. However, the role of chromatin modifiers in the repair of platinum DNA damage in ovarian cancer is not well understood. We demonstrate that the PRC1 complex member RING1A mediates monoubiquitination of lysine 119 of phosphorylated H2AX (γH2AXub1) at sites of platinum DNA damage in ovarian cancer cells. After platinum treatment, our results reveal that NER and HRR both contribute to RING1A localization and γH2AX monoubiquitination. Importantly, replication protein A, involved in both NER and HRR, mediates RING1A localization to sites of damage. Furthermore, RING1A deficiency impairs the activation of the G2-M DNA damage checkpoint, reduces the ability of ovarian cancer cells to repair platinum DNA damage, and increases sensitivity to platinum. IMPLICATIONS: Elucidating the role of RING1A in the DDR to platinum agents will allow for the identification of therapeutic targets to improve the response of ovarian cancer to standard chemotherapy regimens.

FBLN5 is targeted by microRNA‑27a‑3p and suppresses tumorigenesis and progression in high‑grade serous ovarian carcinoma.

High-grade serous ovarian carcinoma (HGSOC) is one of the most lethal gynecological malignancies; however, the precise molecular mechanisms have not been fully characterized. Fibulin-5 (FBLN-5) is an extracellular matrix (ECM) glycoprotein, and plays a crucial role in maintaining the stability of ECM structures, regulating cell proliferation and tumorigenesis. In the present study, the expression of FBLN-5, as determined by western blot analysis and immunohistochemistry, was significantly increased in normal fallopian tube (FT) samples compared with that in HGSOC samples, and decreased FBLN5 expression was associated with unfavorable prognosis of HGSOC. Functional characterization revealed that FBLN5 overexpression significantly inhibited migration, invasion and proliferation abilities of ovarian cancer cells in vitro. Furthermore, micro (mi)RNA-27a-3p (miR-27a-3p) was revealed to be increased in HGSOC, and dual-luciferase reporter assay indicated that miR-27a-3p was functioned as a negative regulator of FBLN5 by directly binding with its 3′-untranslated region. Collectively, FBLN5 expression was associated with prognosis, proliferation, and metastasis in HGSOC. We hypothesized that FBLN5 was targeted by miR-27a-3p and may serve as a biomarker and provide a new therapeutic approach for the treatment of HGSOC.

CircKRT7-miR-29a-3p-COL1A1 Axis Promotes Ovarian Cancer Cell Progression.

BackgroundCircular RNA (circRNA) has emerged as an important regulator in the progression of human diseases. However, the role of circRNAs in ovarian cancer remains largely unknown.Materials and MethodsDNA sequencing and PCR were used to identify the existence and expression of circKRT7. The targeting relationship between circKRT7/miR-29a-3p and miR-29a-3p/COL1A1 was verified by fluorescence reporter assay. In vitro, colony formation, transwell and wound healing assay were used to detect the effects of circKRT7 and miR-29a-3p on the proliferation, migration and invasion ability of ovarian cancer cells. In vivo, xenograft tumor model was performed to validate the role of circKRT7 and miR-29a-3p in tumor growth.ResultsWe found that circKRT7 can promote the proliferation and metastasis of ovarian cancer cells by absorbing miR-29a-3p, which leads to the up-regulation of COL1A1. In vitro, knock-down of circKRT7 can inhibit the migration and invasion of ovarian cancer cells. This effect of circKRT7 is achieved by adsorbing miR-29a-3p and subsequently COL1A1 release. In vivo experiments, the reduction of circKRT7 expression can also slow tumor growth, and this inhibition was partly counteracted after miR-29a-3p repression.ConclusionOverall, circKRT7 promotes EMT-related cell progression by absorbing miR-29a-3p in ovarian cancer. This suggests the crucial role of circular RNA in the malignant evolution in cancer.

MicroRNA-132 inhibits the proliferation, migration, and invasion of ovarian cancer cells by regulating CT10 oncogenic gene homolog II-related signaling pathways.

BackgroundDespite a large amount of evidence showing the involvement of microRNA-132 (miR-132) in the occurrence and prognosis of many different types of cancer, the role of miR-132 in ovarian cancer and its potential molecular mechanism have yet to be fully explained.MethodWe studied the biological function and molecular mechanism of miR-132 in ovarian cancer cell lines and clinical tissue samples using quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blot, Luciferase reporter assay, CCK8 test, colony formation test, and scratch and Transwell assays.ResultsThe expression level of miR-132 was significantly reduced in ovarian cancer cell lines and clinical tissue samples. When the level of miR-132 was increased, the proliferation, colony-forming, migration, and invasion abilities of ovarian cancer cells were significantly inhibited. We found that miR-132 inhibits the expression of transcription factor CT10 Oncogenic Gene Homologue II (CRKII) through specific targeting of mRNA 3'-UTR. We also observed a significant increase in CRKII expression in ovarian cancer. Notably, CRKII expression was negatively correlated with miR-132 expression in clinical ovarian cancer tissue. Down-regulation of CRKII had a similar inhibitory effect on miR-132 overexpression in ovarian cancer cells, while excessive expression of CRKII reversed the inhibitory effect mediated by the excessive expression of miR-132.ConclusionsmiR-132 inhibits the proliferation, invasion, and migration abilities of ovarian cancer cells through targeting CRKII.

MiR-1224-5p inhibits the proliferation and invasion of ovarian cancer via targeting SND1.

Emerging evidences have indicated that abnormal expression of microRNAs (miRNAs) contributed to carcinogenesis of ovarian cancer. However, the molecular mechanism of many aberrant expressed miRNAs was not known. Here, we discovered that miR-1224-5p was a downregulated miRNA in ovarian cancer via bioinformatic analysis and RT-qPCR. It was found that upregulation of miR-1224-5p inhibited cell proliferation and invasion ability of ovarian cancer cells. SND1, a well-characterized oncogene, was predicted as a target gene of miR-1224-5p. The western blotting, dual luciferase reporter assay, RNA-binding protein immunoprecipitation assay, and RT-qPCR demonstrated SND1 as a target gene of miR-1224-5p in ovarian cancer. MiR-1224-5p inhibited the expression of mesenchymal markers and increased the expression of epithelial markers in ovarian cancer cells via targeting SND1, indicating miR-1224-5p was involved in epithelial mesenchymal transition. The rescue assay manifested that miR-1224-5p-regulated cell proliferation and invasion mainly rely on downregulation of SND1 in ovarian cancer cells. In conclusion, our study revealed a direct regulatory association between miR-1224-5p and SND1 and their involvement in ovarian carcinogenesis.

Vitamin D regulates cell viability, migration and proliferation by suppressing galectin-3 (Gal-3) gene in ovarian cancer cells

Vitamin D deficiency is identified as a risk factor for the occurrence and recurrence of ovarian cancer. Galectin-3 (Gal-3) participates in many physiological and pathological processes. In present study, serum vitamin D level was detected using chemiluminescence enzyme immunoassay. Gal-3 expression was examined using real-time polymerase chain reaction (PCR), Western blot and immunocytochemistry analysis. SKOV3 cells viability was assessed by the water-soluble tetrazolium salt (WST-1) assay, the migration of SKOV3 cells was detected using transwell assay, and the proliferation of SKOV3 cells was measured by 3H-thymidine incorporation (3H-TdR). Our study demonstrated that vitamin D levels were lower in 40 ovarian cancer patients: vitamin D deficiency is closely related to the pathogenesis of ovarian cancer. Treatment with vitamin D reduced the migration and proliferation of ovarian cancer cells. Gal-3 was overexpressed in ovarian cancer, which could induce the viability, migration and proliferation ability of ovarian cancer cells, and these effects were abrogated by vitamin D downregulating the expression of Gal-3 gene. Therefore, our results support that vitamin D may suppress Gal-3-induced viability, migration and proliferation ability of ovarian cancer cells, which suggests that the use of vitamin D may have beneficial effects in preventing and treating ovarian cancer.

Overexpression of miR-32 inhibits the proliferation and metastasis of ovarian cancer cells by targeting BTLA.

The purpose of this study was to explore the role of microRNA-32 (miR-32) in ovarian cancer and the possible underlying mechanism. Ovarian cancer tissues were collected from 100 patients diagnosed with ovarian cancer in our hospital. Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) was used to detect the expression levels of miR-32 and its target gene in ovarian tissues. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay was conducted to detect the proliferation of ovarian cancer cells. Meanwhile, the transwell and wound healing assays were used to evaluate the migration and invasion abilities of ovarian cancer cells, respectively. Bioinformatics (including TargetScan, miRDB, and microRNA) were used to predict the target genes of miR-32. Furthermore, The Dual-Luciferase reporter gene assay was performed to verify the binding relationship. MiR-32 was significantly downregulated in both ovarian cancer tissues and cells. The overexpression of miR-32 significantly inhibited the proliferation, migration, and invasion of ovarian cancer cells. B and T lymphocyte associated (BTLA) was screened out as a target gene of miR-32. Furthermore, BTLA could counteract the effects of miR-32 on ovarian cancer cells. Acting as a suppressor gene, miR-32 inhibited the malignant behaviors of ovarian cancer cells by regulating its target gene BTLA.

Chemoresistant ovarian cancer enhances its migration abilities by increasing store-operated Ca2+ entry-mediated turnover of focal adhesions

BackgroundAmong gynecological cancers, ovarian carcinoma has the highest mortality rate, and chemoresistance is highly prevalent in this cancer. Therefore, novel strategies are required to improve its poor prognosis. Formation and disassembly of focal adhesions are regulated dynamically during cell migration, which plays an essential role in cancer metastasis. Metastasis is intricately linked with resistance to chemotherapy, but the molecular basis for this link is unknown.MethodsTranswell migration and wound healing migration assays were used to analyze the migration ability of ovarian cancer cells. Real-time recordings by total internal reflection fluorescence microscope (TIRFM) were performed to assess the turnover of focal adhesions with fluorescence protein-tagged focal adhesion molecules. SOCE inhibitors were used to verify the effects of SOCE on focal adhesion dynamics, cell migration, and chemoresistance in chemoresistant cells.ResultsWe found that mesenchymal-like chemoresistant IGROV1 ovarian cancer cells have higher migration properties because of their rapid regulation of focal adhesion dynamics through FAK, paxillin, vinculin, and talin. Focal adhesions in chemoresistant cells, they were smaller and exhibited strong adhesive force, which caused the cells to migrate rapidly. Store-operated Ca2+ entry (SOCE) regulates focal adhesion turnover, and cell polarization and migration. Herein, we compared SOCE upregulation in chemoresistant ovarian cancer cells to its parental cells. SOCE inhibitors attenuated the assembly and disassembly of focal adhesions significantly. Results of wound healing and transwell assays revealed that SOCE inhibitors decreased chemoresistant cell migration. Additionally, SOCE inhibitors combined with chemotherapeutic drugs could reverse ovarian cancer drug resistance.ConclusionOur findings describe the role of SOCE in chemoresistance-mediated focal adhesion turnover, cell migration, and viability. Consequently, SOCE might be a promising therapeutic target in epithelial ovarian cancer.Graphical abstract