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.

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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.

Matrix metalloproteinase 2 (MMP-2) and membrane type 1 matrix metalloproteinase (MT1-MMP) have been identified as important participants in tumor invasion, metastasis, and angiogenesis. Membrane type 1 matrix metalloproteinase has also been recognized as a major activator of MMP-2. The purpose of this study was to investigate epidermal growth factor (EGF) mediating signal pathways in the regulation of MMP-2 and MT1-MMP in SiHa cells, a cervical cancer cell line. We showed here that EGF induced the expression of MT1-MMP and inhibited the expression of MMP-2 at both the mRNA and protein levels. Membrane type 1 matrix metalloproteinase induction was blocked by mitogen-activated protein kinase or extracellular signal-regulated kinase inhibitors PD98059 and U0126 but not by phosphatidylinositol-3 kinase (PI3-K) inhibitors LY294002 and wortmannin. Interestingly, the mitogen-activated protein kinase or extracellular signal-regulated kinase inhibitors PD98059 and U0126 actually increased MMP-2 mRNA and protein synthesis, whereas the PI3-K inhibitors LY294002 and wortmannin further suppressed the expression of MMP-2. Our results suggest that EGF receptor up-regulated the expression of MT1-MMP and down-regulated the synthesis of MMP-2 through the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway while concomitantly transmitting a mild positive regulatory signal to the expression of MMP-2 via the PI3-K/AKT pathway in SiHa cells. Furthermore, we found that EGF elevated the activity of MMP-2 in culture media.