scholarly journals Knockdown of BRCA2 enhances cisplatin and cisplatin-induced autophagy in ovarian cancer cells

2018 ◽  
Vol 25 (1) ◽  
pp. 69-82 ◽  
Author(s):  
Biao Wan ◽  
Leheyi Dai ◽  
Li Wang ◽  
Ying Zhang ◽  
Hong Huang ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Median Time ◽  
Progression Free Survival ◽  
Ovarian Cancer Cells ◽  
Intact Cells ◽  
Ovarian Cancer Cell Lines ◽  
Tumor Tissues ◽  
Cancer Tissues

Clinical implications of the BRCA2 expression level on treatments of ovarian cancer are controversial. Here, we demonstrated that platinum-resistant cancer had a higher percentage of high BRCA2 level (87.5% vs 43.6%, P = 0.001), and that patients with a low BRCA2 level in cancer tissues had longer progression-free survival (with a median time of 28.0 vs 12.0 months, P < 0.001) and platinum-free duration (with a median time of 19.0 vs 5.0 months, P < 0.001) compared with those with a high BRCA2 level. In human ovarian cancer cell lines CAOV-3 and ES-2, cisplatin induced an upregulation of the RAD51 protein, which was inhibited after silencing BRCA2; silencing BRCA2 enhanced the action of cisplatin in vitro and in vivo. Knockdown of BRCA2 promoted cisplatin-induced autophagy. Interestingly, the autophagy blocker chloroquine enhanced cisplatin in BRCA2-silenced cells accompanied by an increase in apoptotic cells, which did not occur in BRCA2-intact cells; chloroquine enhanced the efficacy of cisplatin against BRCA2-silenced CAOV-3 tumors in vivo, with an increase in LC3-II level in tumor tissues. Sensitization of cisplatin was also observed in BRCA2-silenced CAOV-3 cells after inhibiting ATG7, confirming that chloroquine modulated the sensitivity via the autophagy pathway. These data suggest that a low BRCA2 level can predict better platinum sensitivity and prognosis, and that the modulation of autophagy can be a chemosensitizer for certain cancers.

scholarly journals Demethoxycurcumin inhibited human epithelia ovarian cancer cells’ growth via up-regulating miR-551a

Tumor Biology ◽  
2017 ◽  
Vol 39 (3) ◽  
pp. 101042831769430 ◽  
Author(s):  
Zhenhua Du ◽  
Xianqun Sha
Keyword(s):  
Ovarian Cancer ◽  
Cell Proliferation ◽  
Cancer Cells ◽  
Ovarian Cancer Cells ◽  
Natural Form ◽  
Ovarian Cancer Cell Lines ◽  
Induced Apoptosis ◽  
Tumor Suppressive Function ◽  
Cancer Tissues

Curcumin is a natural agent that has ability to dampen tumor cells’ growth. However, the natural form of curcumin is prone to degrade and unstable in vitro. Here, we demonstrated that demethoxycurcumin (a curcumin-related demethoxy compound) could inhibit cell proliferation and induce apoptosis of ovarian cancer cells. Moreover, IRS2/PI3K/Akt axis was inactivated in cells treated with demethoxycurcumin. Quantitative real-time reverse transcription polymerase chain reaction demonstrated that miR-551a was down-regulated in ovarian cancer tissues and ovarian cancer cell lines. Over-expression of miR-551a inhibited cell proliferation and induced apoptosis of ovarian cancer cells, whereas down-regulation of miR-551a exerted the opposite function. Luciferase assays confirmed that there was a binding site of miR-551a in IRS2, and we found that miR-551a exerted tumor-suppressive function by targeting IRS2 in ovarian cancer cells. Remarkably, miR-551a was up-regulated in the cells treated with demethoxycurcumin, and demethoxycurcumin suppressed IRS2 by restoration of miR-551a. In conclusion, demethoxycurcumin hindered ovarian cancer cells’ malignant progress via up-regulating miR-551a.

scholarly journals METTL3 promotes the initiation and metastasis of ovarian cancer by inhibiting CCNG2 expression via promoting the maturation of pri-microRNA-1246

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xuehan Bi ◽  
Xiao Lv ◽  
Dajiang Liu ◽  
Hongtao Guo ◽  
Guang Yao ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Molecular Mechanisms ◽  
High Expression ◽  
Ovarian Cancer Cells ◽  
Inadequate Knowledge ◽  
And Migration ◽  
Cancer Tissues

AbstractOvarian cancer is a common gynecological malignant tumor with a high mortality rate and poor prognosis. There is inadequate knowledge of the molecular mechanisms underlying ovarian cancer. We examined the expression of methyltransferase-like 3 (METTL3) in tumor specimens using RT-qPCR, immunohistochemistry, and Western blot analysis, and tested the methylation of METTL3 by MSP. Levels of METTL3, miR-1246, pri-miR-1246 and CCNG2 were then analyzed and their effects on cell biological processes were also investigated, using in vivo assay to validate the in vitro findings. METTL3 showed hypomethylation and high expression in ovarian cancer tissues and cells. Hypomethylation of METTL3 was pronounced in ovarian cancer samples, which was negatively associated with patient survival. Decreased METTL3 inhibited the proliferation and migration of ovarian cancer cells and promoted apoptosis, while METTL3 overexpression exerted opposite effects. Mechanistically, METTL3 aggravated ovarian cancer by targeting miR-1246, while miR-1246 targeted and inhibited CCNG2 expression. High expression of METTL3 downregulated CCNG2, promoted the metabolism and growth of transplanted tumors in nude mice, and inhibited apoptosis. The current study highlights the promoting role of METTL3 in the development of ovarian cancer, and presents new targets for its treatment.

scholarly journals An Effective Inhibitory Strategy of Low Steady Magnetic Field on Ovarian Cancer

2021 ◽  
Author(s):  
Xiaodi Li ◽  
Yanwen Fang ◽  
Zhicai Fang ◽  
Ping Wang ◽  
Jun Zhu
Keyword(s):  
Magnetic Field ◽  
Ovarian Cancer ◽  
Cancer Cells ◽  
Cell Model ◽  
Inhibitory Effect ◽  
Ovarian Cancer Cells ◽  
Magnetic Intensity ◽  
Ovarian Cancer Cell Lines

Abstract To estimate the effect of a steady-state magnetic field (SMF) with low magnetic intensity gradient on the apoptosis-promoting factors related to cancer cells, we systematically select SMF with 0.2T, 0.4T and 0.6T to study their effect on different ovarian cancer lines. An in vitro cell model system about two kinds of ovarian cancer lines is established, whose viability and intracellular factors are detected by CCK-8, confocal microscopy and flow cytometry method. The results demonstrate that the apoptosis rate of ovarian cancer cells is increased with the enhancement of SMF magnetic intensity. Furthermore, we detect an increasing ROS and intracellular Ca2+ levels in ovarian cancer cells, which can be caused by SMF. The results suggest that ROS and Ca2+ levels are the main reason for the significant apoptosis of ovarian cancer cell lines in SMF. Moreover, an in vivo experiment also reveals that SMF has a strong inhibitory effect on ovarian cancer. Therefore, the inhibitory strategy is an effective, which has a great potential in the treatment of drug-resistant ovarian cancer.

scholarly journals Targeting Ovarian Cancer Cells Overexpressing CD44 with Immunoliposomes Encapsulating Glycosylated Paclitaxel

2019 ◽  
Vol 20 (5) ◽  
pp. 1042 ◽  
Author(s):  
Apriliana Cahya Khayrani ◽  
Hafizah Mahmud ◽  
Aung Ko Ko Oo ◽  
Maram H. Zahra ◽  
Miharu Oze ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Stem Cell Marker ◽  
Ovarian Cancer Cells ◽  
Cancer Therapies ◽  
Ovarian Cancer Cell Lines ◽  
Tumor Selective

Paclitaxel (PTX) is one of the front-line drugs approved for the treatment of ovarian cancer. However, the application of PTX is limited due to the significant hydrophobicity and poor pharmacokinetics. We previously reported target-directed liposomes carrying tumor-selective conjugated antibody and encapsulated glycosylated PTX (gPTX-L) which successfully overcome the PTX limitation. The tubulin stabilizing activity of gPTX was equivalent to that of PTX while the cytotoxic activity of gPTX was reduced. In human ovarian cancer cell lines, SK-OV-3 and OVK18, the concentration at which cell growth was inhibited by 50% (IC50) for gPTX range from 15–20 nM, which was sensitive enough to address gPTX-L with tumor-selective antibody coupling for ovarian cancer therapy. The cell membrane receptor CD44 is associated with cancer progression and has been recognized as a cancer stem cell marker including ovarian cancer, becoming a suitable candidate to be targeted by gPTX-L therapy. In this study, gPTX-loading liposomes conjugated with anti-CD44 antibody (gPTX-IL) were assessed for the efficacy of targeting CD44-positive ovarian cancer cells. We successfully encapsulated gPTX into liposomes with the loading efficiency (LE) more than 80% in both of gPTX-L and gPTX-IL with a diameter of approximately 100 nm with efficacy of enhanced cytotoxicity in vitro and of convenient treatment in vivo. As the result, gPTX-IL efficiently suppressed tumor growth in vivo. Therefore gPTX-IL could be a promising formulation for effective ovarian cancer therapies.

scholarly journals Forkhead Box Protein C2 (FOXC2) Promotes the Resistance of Human Ovarian Cancer Cells to Cisplatin In Vitro and In Vivo

2016 ◽  
Vol 39 (1) ◽  
pp. 242-252 ◽  
Author(s):  
Chanjuan Li ◽  
Hongjuan Ding ◽  
Jing Tian ◽  
Lili Wu ◽  
Yun Wang ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cancer Cells ◽  
Cell Line ◽  
Mapk Signaling ◽  
Ovarian Cancer Cells ◽  
Human Ovarian Cancer ◽  
Cancer Tissues ◽  
Mapk Signaling Pathways

Background/Aims: FOXC2 has been reported to play a role in tumor progression, but the correlations of FOXC2 with the cisplatin (CDDP) resistance of ovarian cancer cells are still unclear. The purpose of the present study is to investigate the roles of FOXC2 in the CDDP resistance of ovarian cancer cells and its possible mechanisms. Methods: Quantitative real-time PCR (qRT-PCR) was performed to detect the expression of FOXC2 mRNA in CDDP-resistant or sensitive ovarian cancer tissues and cell lines (SKOV3/CDDP and SKOV3). Gain- and loss-of-function assays were performed to analyze the effects of FOXC2 knockdown or overexpression on the in vitro and in vivo sensitivity of ovarian cancer cells to CDDP and its possible molecular mechanisms. Results: The relative expression level of FOXC2 mRNA in CDDP-resistant ovarian cancer tissues was higher than that in CDDP-sensitive tissues. Also, the expression of FOXC2 mRNA and protein in CDDP-resistant ovarian cancer cell line (SKOV3/CDDP) cell line was higher than that in its parental cell line (SOKV3). Small hairpin RNA (shRNA)-mediated FOXC2 knockdown significantly increased the in vitro and in vive sensitivity of SKOV3/CDDP cells to CDDP by enhancing apoptosis, while upregulation of FOXC2 significantly decreased the in vitro and in vivo sensitivity of SKOV3 cells to CDDP by reducing apoptosis. Furthermore, FOXC2 activates the Akt and MAPK signaling pathways, and then induced the decreased expression of Bcl-2 protein and the increased expression of Bax and cleaved caspase-3 proteins. Conclusions: FOXC2 mediates the CDDP resistance of ovarian cancer cells by activation of the Akt and MAPK signaling pathways, and may be a potential novel therapeutic target for overcoming CDDP resistance in human ovarian cancer.

scholarly journals Combining ReACp53 with Carboplatin to Target High-Grade Serous Ovarian Cancers

Cancers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 5908
Author(s):  
Adam Neal ◽  
Tiffany Lai ◽  
Tanya Singh ◽  
Neela Rahseparian ◽  
Tristan Grogan ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cancer Cells ◽  
Synergistic Effects ◽  
Ovarian Cancer Cells ◽  
High Grade ◽  
Ovarian Carcinomas ◽  
Ovarian Cancer Cell Lines ◽  
Poor Outcomes

Ovarian malignancies are a leading cause of cancer-related death for US women. High-grade serous ovarian carcinomas (HGSOCs), the most common ovarian cancer subtype, are aggressive tumors with poor outcomes. Mutations in TP53 are common in HGSOCs, with a subset resulting in p53 aggregation and misregulation. ReACp53 is a peptide designed to inhibit mutant p53 aggregation and has been shown efficacious in targeting cancer cells in vitro and in vivo. As p53 regulates apoptosis, combining ReACp53 with carboplatin represents a logical therapeutic strategy. The efficacy of this combinatorial approach was tested in eight ovarian cancer cell lines and 10 patient HGSOC samples using an in vitro organoid drug assay, with the SynergyFinder tool utilized for calculating drug interactions. Results demonstrate that the addition of ReACp53 to carboplatin enhanced tumor cell targeting in the majority of samples tested, with synergistic effects measured in 2 samples, additivity measured in 14 samples, and antagonism measured in 1 sample. This combination was found to be synergistic in OVCAR3 ovarian cancer cells in vitro through enhanced apoptosis, and survival of mice bearing OVCAR3 intraperitoneal xenografts was extended when treated with the addition of ReACp53 to carboplatin versus carboplatin alone. Results suggest that carboplatin and ReACp53 may be a potential strategy in targeting a subset of HGSOCs.

scholarly journals ADAR1 Prevents R-loop Accumulation-Driven ATR Pathway Activation in Ovarian Cancer

2020 ◽  
Author(s):  
hanwei cui ◽  
Qian Yi ◽  
Min Tian ◽  
Yuteng Liang ◽  
Jie Huang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Ovarian Cancer ◽  
Cancer Cells ◽  
Ovarian Cancer Cell ◽  
Ovarian Cancer Cells ◽  
Pathway Activation ◽  
Rna Immunoprecipitation ◽  
Cancer Tissues

Abstract BackgroundAdenosine (A)-to-inosine (I) RNA editing is the most prevalent RNA editing mechanism, in which adenosine deaminases acting on RNA 1 (ADAR1) is a major adenosine deaminase. Increasing evidence suggests that editing dysregulation of ADAR1 plays an important role in human tumorigenesis, while the underlying mechanism remains elusive. MethodsThe clinical relevance of ADAR1 was analyzed by real-time PCR, western blotting and immunohistochemistry of ovarian cancer tissues. ADAR1 function on ovarian cancer cells in vitro were explored by colony formation assay, transwell assay and Brdu-based cell cycle assay in vitro and xenograft models in vivo. Western blotting, immunostaining and DNA/RNA immunoprecipitation-qPCR were conducted to confirm DNA damage and R-loop accumulation in ovarian cancer cells. Co-immunoprecipitation and DNA/RNA immunoprecipitation were performed to detect interaction of DHX9, ADAR1 and R-loop complex in ovarian cancer cells.ResultsWe demonstrated that ADAR1 was highly expressed in ovarian cancer tissues and negatively correlated with progression free survival of ovarian cancer patients. Importantly, silence of ADAR1 repressed ovarian cancer cell growth and colony formation in vitro and inhibited ovarian cancer cell tumorigenesis in vivo. Further cell cycle and transcriptome profile analysis revealed that silence of ADAR1 in ovarian cancer cells induced cell cycle arrest at G1/G0 stage. Mechanically, loss of ADAR1 caused R-loop abnormal accumulation, thereby contributing to single stand DNA break and ATR pathway activation. Additionally, ADAR1 interacted with DHX9 to regulate R-loop complex formation, and A-to-I editing of nascent RNA repressed R-loop formation during co-transcriptional process. ConclusionsOur results identify a novel ADAR1/R-loop/ATR axis critical for ovarian cancer progression and a potential target for ovarian cancer therapy.

scholarly journals Down-regulation of ZNF252P-AS1 alleviates ovarian cancer progression by binding miR-324-3p to downregulate LY6K

2022 ◽  
Vol 15 (1) ◽  
Author(s):  
Li Geng ◽  
Zhongqiu Wang ◽  
Yongju Tian
Keyword(s):  
Ovarian Cancer ◽  
Cancer Cell ◽  
Cancer Progression ◽  
Epithelial To Mesenchymal Transition ◽  
Ovarian Cancer Cells ◽  
Mesenchymal Transition ◽  
In Vivo Experiments ◽  
Cancer Tissues

Abstract Background Ovarian cancer is a common gynecological malignant disease in women. Our work aimed to study the specific functions of ZNF252P antisense RNA 1 (ZNF252P-AS1) in ovarian cancer. Methods ZNF252P-AS1, miR-324-3p, and lymphocyte antigen 6 family member K (LY6K) expression were analyzed by bioinformatics tools in ovarian cancer tissues and was quantified by qRT-PCR in ovarian cancer cells. The effect of ZNF252P-AS1 knockdown, miR-324-3p suppression, and LY6K over-expression on apoptosis, cell viability, invasion, migration, and epithelial to mesenchymal transition (EMT) was determined in vitro by using colony formation and EdU assays, flow cytometry, transwell assay, and Western blot. The interactions between ZNF252P-AS1 and miR-324-3p and between miR-324-3p and LY6K were validated by luciferase assays. The effects of restraining ZNF252P-AS1 in vivo were studied using BALB/c male nude mice. Results ZNF252P-AS1 and LY6K levels were up-regulated, while miR-324-3p was declined in ovarian cancer tissues and cells. ZNF252P-AS1 knockdown reduced ovarian cancer cell proliferation, invasion, migration, and EMT, whereas promoted its apoptosis. Besides, ZNF252P-AS1 interacted with miR-324-3p and reversely regulated its level, and miR-324-3p was directly bound to LY6K and negatively regulated its expression. Moreover, ZNF252P-AS1 knockdown reversed the effect of miR-324-3p on cancer cell apoptosis, growth, migration, invasion, and EMT. Similar results were discovered in the rescue experiments between miR-324-3p and LY6K. Additionally, mouse models in vivo experiments further validated that ZNF252P-AS1 knockdown distinctly inhibited tumor growth. Conclusion ZNF252P-AS1 mediated miR-324-3p/LY6K signaling to facilitate progression of ovarian cancer.

scholarly journals RETRACTED ARTICLE: Long noncoding RNA MLK7-AS1 promotes ovarian cancer cells progression by modulating miR-375/YAP1 axis

2018 ◽  
Vol 37 (1) ◽  
Author(s):  
Huan Yan ◽  
Hong Li ◽  
Pengyun Li ◽  
Xia Li ◽  
Jianjian Lin ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Wound Healing ◽  
Cancer Cells ◽  
Cell Lines ◽  
Colony Formation ◽  
Ovarian Cancer Cells ◽  
Human Ovarian Cancer ◽  
Cancer Tissues

Abstract Background Long noncoding RNAs (LncRNAs) have been reported to be abnormally expressed in human ovarian cancer and associated with the proliferation and metastasis of cancer cells. The objective of this study was to investigate the role and the underlying mechanisms of LncRNA MAP3K20 antisense RNA 1 (MLK7-AS1) in ovarian cancer. Methods The expression level of MLK7-AS1 was investigated in human ovarian cancer tissues and cell lines. The effects of MLK7-AS1 knockdown on ovarian cancer cell proliferation, migration, invasion and apoptosis were evaluated in vitro using MTT, colony formation assays, wound healing assays, transwell assays and flow cytometry. Furthermore, the in vivo effects were determined using the immunodeficient NSG female mice. Luciferase reporter assays were employed to identify interactions among MLK7-AS1 and its target genes. Results In the current study, MLK7-AS1 was specifically upregulated in ovarian cancer tissues and cell lines. Knockdown of MLK7-AS1 inhibited the ability of cell migration, invasion, proliferation, colony formation and wound healing, whereas promoted cell apoptosis in vitro. By using online tools and mechanistic analysis, we demonstrated that MLK7-AS1 could directly bind to miR-375 and downregulate its expression. Besides, MLK7-AS1 reversed the inhibitory effect of miR-375 on the growth of ovarian cancer cells, which might be involved in the upregulation of Yes-associated protein 1 (YAP1) expression. Moreover, knockdown MLK7-AS1 expression inhibited primary tumor growth in ovary and metastatic tumors in multiple peritoneal organs including liver and spleen in vivo, which were partly abolished by miR-375 inhibition. Mechanically, we found that MLK7-AS1 modulated the epithelial-mesenchymal transition (EMT) process by interacting with miR-375/YAP1 both in vivo and vitro, which promoted the expression of Slug. Conclusions Taken together, our study showed for the first time that MLK7-AS1 interacted with miR-375 to promote proliferation, metastasis, and EMT process in ovarian cancer cells through upregulating YAP1.

scholarly journals FBW7 suppresses ovarian cancer development by targeting the N6-methyladenosine binding protein YTHDF2

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Fei Xu ◽  
Jiajia Li ◽  
Mengdong Ni ◽  
Jingyi Cheng ◽  
Haiyun Zhao ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cancer Progression ◽  
Biological Effects ◽  
Ovarian Cancer Cells ◽  
Promoting Effect ◽  
In Vivo Models ◽  
Cancer Cell Survival ◽  
Cancer Tissues

Abstract Background The tumor suppressor FBW7 is the substrate recognition component of the SCF E3-ubiquitin ligase complex that mediates proteolytic degradation of various oncogenic proteins. However, the role of FBW7 in ovarian cancer progression remains inadequately understood. Methods IP-MASS, co-IP, immunohistochemistry, and western blotting were used to identify the potential substrate of FBW7 in ovarian cancer. The biological effects of FBW7 were investigated using in vitro and in vivo models. LC/MS was used to detect the m6A levels in ovarian cancer tissues. MeRIP-Seq and RNA-Seq were used to assess the downstream targets of YTHDF2. Results We unveil that FBW7 is markedly down-regulated in ovarian cancer tissues and its high expression is associated with favorable prognosis and elevated m6A modification levels. Consistently, ectopic FBW7 inhibits ovarian cancer cell survival and proliferation in vitro and in vivo, while ablation of FBW7 empowers propagation of ovarian cancer cells. In addition, the m6A reader protein, YTHDF2, is identified as a novel substrate for FBW7. FBW7 counteracts the tumor-promoting effect of YTHDF2 by inducing proteasomal degradation of the latter in ovarian cancer. Furthermore, YTHDF2 globally regulates the turnover of m6A-modified mRNAs, including the pro-apoptotic gene BMF. Conclusions Our study has demonstrated that FBW7 suppresses tumor growth and progression via antagonizing YTHDF2-mediated BMF mRNA decay in ovarian cancer.

Sign in / Sign up

Export Citation Format

Share Document