Tiefang Song

In recent years, circular RNAs have been shown to serve as essential regulators in several human cancers. Nevertheless, the function and mechanism of CircRNA in cervical cancer remain elusive. In the present study, we showed that hsa_circRNA_101996 was highly expressed in cervical cancer tissues compared with matched normal tissues by bioinformatics analysis. We showed that the expression level of hsa_circRNA_101996 in cervical cancer tissues was positively correlated with TNM stage, tumor size, and lymph node metastasis. Moreover, higher levels of hsa_circRNA_101996 were related to poor outcomes of cervical cancer patients. We found that knockdown of hsa_circRNA_101996 significantly inhibited the proliferation, cell cycle, migration, and invasion of cervical cancer cells. Mechanistically, we demonstrated that hsa_circRNA_101996 served as a sponge of miR-8075, which targeted TPX2 in cervical cancer cells. We showed that miR-8075 that was downregulated in cervical cancer tissues repressed cervical cancer cell proliferation, migration, and invasion. Furthermore, we validated that upregulation of TPX2 by hsa_circRNA_101996-mediated inhibition of miR-8075 contributed to cervical cancer proliferation, migration, and invasion. Taken together, our findings revealed a novel mechanism that hsa_circRNA_101996-miR-8075-TPX2 network promoted cervical cancer progression.

Previous studies have demonstrated that the presence of Hox transcript antisense intergenic RNA (HOTAIR) is correlated with poor survival in several types of cancer, including breast cancer, and promotes tumor metastasis. Currently, little is known regarding the correlation between HOTAIR and chemoresistance in cancer. The current study aimed to investigate the role of HOTAIR in epithelial ovarian cancer, and the correlation between HOTAIR and cisplatin resistance. Reverse transcription-quantitative polymerase chain reaction was conducted to detect HOTAIR expression in the ovarian specimens and ovarian carcinoma cell lines. The results indicated that the expression level of HOTAIR was higher in epithelial ovarian cancer tissues than the level in the benign ovarian tissues. The expression level was also higher in late-stage malignant ovarian tumors compared with the level in early-stage tumors. Levels of HOTAIR were also higher in the SKOV-3CDDP/R cisplatin-resistant ovarian carcinoma cell line than in the SKOV-3 cisplatin-sensitive cell line. The knockdown of HOTAIR using siRNAs with transfection reagent suppressed cell proliferation, reduced the invasion ability of the cells and notably, it restored cisplatin-sensitivity of the cisplatin-resistant cells specifically by enhancing cisplatin-induced cytotoxicity and apoptosis in SKOV-3CDDP/R cells. In conclusion, HOTAIR may be used in the development of novel treatments for ovarian cancer, particularly those that are resistant to conventional therapies.

BACKGROUND: Emerging evidence shows that Hippo signal pathways can regulate the progression of various cancer. While the roles of Yes-associated protein (YAP), the key transducer of Hippo signals, in the development of endometrial cancer (EC) are rarely investigated. METHODS: The expression of YAP in endometrial cancer cells and tissues was measured. Its roles in proliferation and expression of interleukins (ILs) were investigated by use of its specific siRNA or inhibitor (verteporfin, VP). RESULTS: YAP was upregulated in endometrial cancer cells and tissues. Knockdown of YAP or VP can suppress the proliferation while increase its chemo-sensitivity of EC cells. We found that targeted inhibition of YAP can decrease the expression of interleukin-6 (IL-6) and IL-11 in EC cells. Recombinant IL-6 or IL-11 can attenuate si-YAP suppressed proliferation of EC cells. Chromatin immunoprecipitation (ChIP) assay suggested that YAP can directly bind with the promoter of IL-6 and induce its transcription. As to IL-11, inhibitor of NF-κB (BAY 11-7082) can significantly down regulate the mRNA expression of IL-11. Over expression of p65 abolished si-YAP suppressed transcription of IL-11. It suggested that NF-κB was involved in the YAP regulated expression of IL-11. CONCLUSIONS: YAP can regulate the proliferation and progression of EC cells. It suggested that targeted inhibition of YAP might be a potent potential approach for EC therapy.

Background: MIAT (myocardial infarction-associated transcript) regulates cell proliferation, apoptosis, and metastasis in several cancers. In this study, the authors aimed to explore the role of MIAT in ovarian cancer. Materials and Methods: The expression of MIAT in ovarian cancer subtypes, normal human ovarian surface epithelial and ovarian cancer cell lines was measured by qualitative real-time polymerase chain reaction (qRT-PCR). OVCAR3 and SKOV3 cells were transfected with MIAT overexpression plasmid or siMIAT. The cell growth ability was then evaluated by CCK-8 and colony formation assays. The cell migration and invasion rate were separately measured by wound-healing and transwell assays. The levels of epithelial–mesenchymal transition (EMT)-associated markers were evaluated by Western blotting. MIAT sponging miR-150-5p was predicted by starBase and confirmed by dual-luciferase reporter assays. The expression of miR-150-5p in OVCAR3 and SKOV3 cells with MIAT overexpression or knockdown, and in ovarian cancer subtypes was also measured by qRT-PCR. Further analyses confirmed the role of MIAT sponging miR-150-5p in ovarian cancer cells. Results: MIAT was highly expressed in mesenchymal subtype ovarian cancer tissues and ovarian cancer cells. In OVCAR3 and SKOV3 cells, overexpression of MIAT promoted, and knockdown of MIAT suppressed the cell growth, migration, invasion, and EMT. miR-150-5p was sponged and regulated by MIAT. miR-150-5p was downregulated in mesenchymal subtype ovarian cancer. Suppression of cell migration, invasion, and EMT caused by miR-150-5p overexpression was rescued by MIAT overexpression. Conclusions: MIAT acts as an oncogene in ovarian cancer cells through sponging miR-150-5p. MIAT or miR-150-5p expression might be a potential prognostic biomarker for ovarian cancer patients. MIAT and miR-150-5p are potential therapeutic targets in treatment of ovarian cancer.

Circular RNAs (circRNAs) appear to be significant modulators in various physiological processes. Recently, it is found that circRNA_101996 exerts important roles in various cancers. Our previous studies showed that circRNA_101996 promoted cervical cancer growth and metastasis by regulating miR-8075/TPX2. However, the potential regulatory role of circRNA_101996 in cervical cancer still needs further investigation. Our results in this study suggested that circRNA_101996 was over-expressed in cervical cancer patients. circRNA_101996 up-regulation remarkably assisted cell proliferation, cell cycle progression, and cell migration in cervical cancer, while circRNA_101996 knockdown exerted the inverse effects. The molecular investigations indicated that circRNA_101996 could increase the expression level of miR-1236-3p, tripartite motif-containing 37 (TRIM37), through binding to miR-1236-3p and reducing its expression. Moreover, in vivo results demonstrated that circRNA_101996 shRNA can function as a tumor suppressor through down-regulating TRIM37 in cervical cancer. In conclusion, our data indicated that circRNA_101996/miR-1236-3p/TRIM37 axis accelerated cervical cancer development, providing novel insights into cervical cancer diagnosis and treatment.