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

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.

2021 ◽  
Vol 11 ◽  
Author(s):  
Ying Zhang ◽  
Yi Sun ◽  
Lin Ding ◽  
Wenjing Shi ◽  
Keshuo Ding ◽  
...  

Breast cancer remains the leading cause of female cancer-related mortalities worldwide. Long non-coding RNAs (LncRNAs) have been increasingly reported to play pivotal roles in tumorigenesis and cancer progression. Herein, we focused on LINC00467, which has never been studied in breast cancer. Silence of LINC00467 suppressed proliferation, migration, invasion and epithelial-to-mesenchymal transition (EMT) of breast cancer cells in vitro, whereas forced expression of LINC00467 exhibited the opposite effects. Furthermore, we demonstrated overexpression of LINC00467 promoted tumor growth, while knockdown of LINC00467 inhibited pulmonary metastasis in vivo. Mechanistically, LINC00467 down-regulated miR-138-5p by acting as a miRNA “sponge”. Besides, LINC00467 also up-regulated the protein level of lin-28 homolog B (LIN28B) via a direct interaction. A higher expression level of LINC00467 was observed in breast cancer tissues as compared to the adjacent normal counterparts and elevated LINC00467 predicted poor overall survival. Our findings suggest LINC00467 promotes progression of breast cancer through interacting with miR-138-5p and LIN28B directly. LINC00467 may serve as a potential candidate for the diagnosis and treatment of breast cancer.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Fei Xu ◽  
Jiajia Li ◽  
Mengdong Ni ◽  
Jingyi Cheng ◽  
Haiyun Zhao ◽  
...  

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.


2021 ◽  
Author(s):  
Wentao Li ◽  
Ismatullah Soufiany ◽  
Xiao Lyu ◽  
Lin Zhao ◽  
Chenfei Lu ◽  
...  

Abstract Background: Mounting evidences have shown the importance of lncRNAs in tumorigenesis and cancer progression. LBX2-AS1 is an oncogenic lncRNA that has been found abnormally expressed in gastric cancer and lung cancer samples. Nevertheless, the biological function of LBX2-AS1 in glioblastoma (GBM) and potential molecular mechanism are largely unclear. Methods: Relative levels of LBX2-AS1 in GBM samples and cell lines were detected by qRT-PCR and FISH. In vivo and in vitro regulatory effects of LBX2-AS1 on cell proliferation, epithelial-to-mesenchymal transition (EMT) and angiogenesis in GBM were examined through xenograft models and functional experiments, respectively. The interaction between Sp1 and LBX2-AS1 was assessed by ChIP. Through bioinformatic analyses, dual-luciferase reporter assay, RIP and Western blot, the regulation of LBX2-AS1 and miR-491-5p on the target gene leukemia Inhibitory factor (LIF) was identified. Results: LBX2-AS1 was upregulated in GBM samples and cell lines, and its transcription was promoted by binding to the transcription factor Sp1. As a lncRNA mainly distributed in the cytoplasm, LBX2-AS1 upregulated LIF, and activated the LIF/STAT3 signaling by exerting the miRNA sponge effect on miR-491-5p, thus promoting cell proliferation, EMT and angiogenesis in GBM. Besides, LBX2-AS1 was unfavorable to the progression of glioma and the survival. Conclusion: Upregulated by Sp1, LBX2-AS1 promotes the progression of GBM by targeting the miR-491-5p/LIF axis. It is suggested that LBX2-AS1 may be a novel diagnostic biomarker and therapeutic target of GBM.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xuehan Bi ◽  
Xiao Lv ◽  
Dajiang Liu ◽  
Hongtao Guo ◽  
Guang Yao ◽  
...  

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.


Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1918
Author(s):  
Yanyuan Wu ◽  
Marianna Sarkissyan ◽  
Ochanya Ogah ◽  
Juri Kim ◽  
Jaydutt V. Vadgama

Background: Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is associated with cancer progression. Our study examined the role of MALAT1 in breast cancer and the mechanisms involved in the regulation of MALAT1. Methods: In vitro cell and in vivo animal models were used to examine the role of MALAT1 in breast cancer. The interaction of FOXO1 (Forkhead Box O1) at the promoter region of MALAT1 was investigated by chromatin immunoprecipitation (ChIP) assay. Results: The data shows an elevated expression of MALAT1 in breast cancer tissues and cells compared to non-cancer tissues and cells. The highest level of MALAT1 was observed in metastatic triple-negative breast cancer and trastuzumab-resistant HER2 (human epidermal growth factor receptor 2) overexpressing (HER2+) cells. Knockdown of MALAT1 in trastuzumab-resistant HER2+ cells reversed epithelial to mesenchymal transition-like phenotype and cell invasiveness. It improved the sensitivity of the cell’s response to trastuzumab. Furthermore, activation of Akt by phosphorylation was associated with the upregulation of MALAT1. The transcription factor FOXO1 regulates the expression of MALAT1 via the PI3/Akt pathway. Conclusions: We show that MALAT1 contributes to HER2+ cell resistance to trastuzumab. Targeting the PI3/Akt pathway and stabilizing FOXO1 translocation could inhibit the upregulation of MALAT1.


2018 ◽  
Vol 25 (1) ◽  
pp. 69-82 ◽  
Author(s):  
Biao Wan ◽  
Leheyi Dai ◽  
Li Wang ◽  
Ying Zhang ◽  
Hong Huang ◽  
...  

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.


2021 ◽  
Author(s):  
Han Wang ◽  
Yingying Zhou ◽  
Siyang Zhang ◽  
Ya Qi ◽  
Min Wang

Abstract Background Small nucleolar RNA host gene 16 (SNHG16) and pre-mRNA processing factor 6(PRPF6) play vital roles in regulatory mechanisms of multiple cancers, but the mechanisms in ovarian cancer (OC) remains poorly understood. Methods The expression of SNHG16 transcripts-SNHG16-L/S in OC tissues were analyzed by real-time PCR (RT-PCR). The expression of PRPF6 in OC tissues were detected by Immunohistochemistry (IHC). Tumorigenesis, epithelial-to-mesenchymal transition (EMT) and PTX-resistance were detected by western blot, transwell, CCK-8 assays, colony formation assays and flow cytometry analyses. Molecular interactions were examined by dual-luciferase reporter gene assay, RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP). Results The results indicated the expression of SNHG16-L/S was opposite in chemo-resistance and chemo-sensitivity tissues of OC. And SNHG16-L/S had different effects on the progression and PTX-resistance of OC cells. SNHG16-L inhibited GATA binding protein 3 (GATA3) transcription through CCAAT/enhancer-binding protein b (CEBPB) to further promote tumorigenesis, EMT and PTX-resistance of OC. Moreover, PRPF6 was upregulated in chemo-resistance tissues of OC. PRPF6 promoted tumorigenesis and PTX-resistance in vitro and in vivo. Mechanistically, PRPF6 induced the alternative splicing of SNHG16 to downregulate SNHG16-L, which further mediated progression and PTX-resistance through upregulating GATA3 in OC. Conclusions Totally, the results demonstrated that PRPF6 promoted progression and PTX-resistance in OC through SNHG16-L/CEBPB/GATA3 axis. Thus, PRPF6 may become a valuable target for OC therapy.


2021 ◽  
Vol 10 ◽  
Author(s):  
Arthur-Quan Tran ◽  
Stephanie A. Sullivan ◽  
Leo Li-Ying Chan ◽  
Yajie Yin ◽  
Wenchuan Sun ◽  
...  

SPR965 is an inhibitor of PI3K and mTOR C1/C2 and has demonstrated anti-tumorigenic activity in a variety of solid tumors. We sought to determine the effects of SPR965 on cell proliferation and tumor growth in human serous ovarian cancer cell lines and a transgenic mouse model of high grade serous ovarian cancer (KpB model) and identify the underlying mechanisms by which SPR965 inhibits cell and tumor growth. SPR965 showed marked anti-proliferative activity by causing cell cycle arrest and inducing cellular stress in ovarian cancer cells. Treatment with SPR965 significantly inhibited tumor growth in KpB mice, accompanied by downregulation of Ki67 and VEGF and upregulation of Bip expression in ovarian tumors. SPR965 also inhibited adhesion and invasion through induction of the epithelial–mesenchymal transition process. As expected, downregulation of phosphorylation of AKT and S6 was observed in SPR965-treated ovarian cancer cells and tumors. Our results suggest that SPR965 has significant anti-tumorigenic effects in serous ovarian cancer in vitro and in vivo. Thus, SPR965 should be evaluated as a promising targeted agent in future clinical trials of ovarian cancer.


2020 ◽  
Author(s):  
Zhuo Wang ◽  
Ping Yin ◽  
Yu Sun ◽  
Lei Na ◽  
Jian Gao ◽  
...  

Abstract Background: High-grade serous ovarian cancer (HGSOC) is lethal mainly due to extensive metastasis. Cancer cell stem-like properties are responsible for HGSOC metastasis. LGR4, a G-protein-coupled receptor, is involved in the maintenance of stem cell self-renewal and activity in some human organs. Methods: TCGA and CCLE database was interrogated for gene mRNA analysis in ovarian cancer tissues and cell lines. The interactions between LGR4 and ELF3 were validated through dual-luciferase reporter assays, Chip assays and Co-IP assays. Gain- and loss-of functions of LGR4, ELF3, FZD5 and WNT7B were performed to identify their roles in the behaviors of ovarian cancer cells. Flowcytometry analysis and tumorisphere formation assays were performed to identified their stem-like properties. In vivo experiments were performed as well.Results: LGR4 was shown to be overexpressed in HGSOCs and maintain the epithelial phenotype of HGSOC cells. LGR4 knockdown suppressed POU5F1, SOX2, PROM1 (CD133) and ALDH1A2 expression. Furthermore, LGR4 knockdown reduced CD133+ and ALDH+ subpopulations and impaired tumorisphere formation. To the contrary, LGR4 overexpression enhanced POU5F1 and SOX2 expression and tumorisphere formation capacity. LGR4 knockdown inhibited HGSOC cell growth and peritoneal seeding in xenograft models. Mechanistically, LGR4 and ELF3, an epithelium-specific transcription factor, formed a reciprocal regulatory loop, which was positively modulated by WNT7B/FZD5 pair. Consistently, knockdown of ELF3, WNT7B, and FZD5, respectively, disrupted HGSOC cell epithelial phenotype and stem-like properties. Conclusion: Together, these data demonstrate that WNT7B/FZD5-LGR4/ELF3 axis maintains HGSOC cell epithelial phenotype and stem-like traits; targeting this axis may prevent HGSOC metastasis.


Cancers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 662 ◽  
Author(s):  
Martyna Pakuła ◽  
Paweł Uruski ◽  
Arkadiusz Niklas ◽  
Aldona Woźniak ◽  
Dariusz Szpurek ◽  
...  

The study was designed to establish whether high aggressiveness of high-grade serous ovarian cancer cells (HGSOCs), which display rapid growth, advanced stage at diagnosis and the highest mortality among all epithelial ovarian cancer histotypes, may be linked with a specific pattern of mesothelial-mesenchymal transition (MMT) elicited by these cells in normal peritoneal mesothelial cells (PMCs). Experiments were performed on primary PMCs, stable and primary ovarian cancer cells, tumors from patients with ovarian cancer, and laboratory animals. Results of in vitro and in vivo tests showed that MMT triggered by HGSOCs (primary cells and OVCAR-3 line) is far more pronounced than the process evoked by cells representing less aggressive ovarian cancer histotypes (A2780, SKOV-3). Mechanistically, HGSOCs induce MMT via Smad 2/3, ILK, TGF-β1, HGF, and IGF-1, whereas A2780 and SKOV-3 cells via exclusively Smad 2/3 and HGF. The conditioned medium from PMCs undergoing MMT promoted the progression of cancer cells and the effects exerted by the cells triggered to undergo MMT by the HGSOCs were significantly stronger than those related to the activity of their less aggressive counterparts. Our findings indicate that MMT in PMCs provoked by HGSOCs is stronger, proceeds via different mechanisms and has more procancerous characteristics than MMT provoked by less aggressive cancer histotypes, which may at least partly explain high aggressiveness of HGSOCs.


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