LINC00673 exerts oncogenic function in cervical cancer by negatively regulating miR-126-5p expression and activates PTEN/PI3K/AKT signaling pathway.
Recent studies have indicated the crucial regulator roles of a long non-coding RNA (lncRNA) LINC00673 in cancer pathogenesis and development. However, the clinical significance and functional effects of LINC00673 in cervical cancer remains unknown.
LINC00673 mRNA expression in cervical cancer tissues was measured by quantitative Real-time PCR (qRT-PCR), and the association between LINC00673 expression and the overall survival (OS) time of patients was analyzed by Kaplan-Meier survival plot. Cell proliferation was assessed using CCK8 assay, Flow cytometry analysis and cell colony formation assay. The association between miR-126-5p and LINC00673 was clarified by Luciferase activity assay. Furthermore, xenografts model in mice in vivo were used to evaluate the effects of LINC00673 expression on tumor growth of cervical cancer.
It was confirmed that the relative mRNA expression of LINC00673 was promoted in cervical cancer tissues and cancer cell lines compared with its corresponding normal tissues and cells (P < 0.05). Higher LINC00673 expression was associated with tumor size, lymph node metastasis, and International Federation of Gynecology and Obstetrics (FIGO) stage (P < 0.05). Survival analysis showed higher LINC00673 expression predicted poor OS of cervical cancer patients, and Multivariate Cox analysis demonstrated that higher LINC00673 expression was identified as an independent risk factor for OS. LINC00673 overexpression promoted cell proliferation and cell cycle progression, but LINC00673 knockdown inhibited cell proliferation and cell cycle progression significantly (P < 0.05). Besides, overexpression of LINC00673 was negatively correlated with lower miR-126-5p expression in cervical cancer tissues. In vivo xenograft tumor assay indicated that LINC00673 silencing reduced the tumor volume and weight. Bioinformatics analysis revealed that miR-126-5p targeted 3'-UTR of LINC00673, and LINC00673 promoted cell proliferation by sponging to miR-126-5p in cervical cancer cells. Additionally, it was demonstrated that LINC00673 significantly activated the PTEN/PI3K/AKT signaling pathway in cervical cancer cells.
These results provide the evidence that LINC00673 overexpression promotes cervical cancer cells progression through regulating miR-126-5p and activating the PTEN/PI3K/AKT signaling pathway, indicating that LINC00673 may be a potential therapeutic target for cervical cancer treatment.
Shi WJ
,Liu H
,Ge YF
,Wu D
,Tan YJ
,Shen YC
,Wang H
,Xu H
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MicroRNA-155-5p promotes hepatocellular carcinoma progression by suppressing PTEN through the PI3K/Akt pathway.
MicroRNA-155-5p (miR-155-5p) has been reported to play an oncogenic role in different human malignancies; however, its role in hepatocellular carcinoma (HCC) progression is not clearly understood. In this study, we used real-time PCR in 20 rats with chemically-induced HCC, 28 human HCC tissues, and the matched paracarcinoma tissues, and HCC cell lines to determine the expression patterns of miR-155-5p and PTEN mRNA. Algorithm-based and experimental strategies, such as dual luciferase gene reporter assays, real-time PCR and western blots were used to identify PTEN as a candidate miR-155-5p target. Gain- and loss-of-function experiments and administration of a PI3K/Akt pathway inhibitor (wortmannin) were used to identify the effects of miR-155-5p and PTEN in MTT assays, flow cytometric analysis, wound healing assays and transwell assays. The results showed that miR-155-5p was highly overexpressed; however, PTEN was underexpressed in the HCC rat models, human HCC tissues and cell lines. In addition, miR-155-5p upregulation and PTEN downregulation were significantly associated with TNM stage (P < 0.05). Through in vitro experiments, we found that miR-155-5p promoted proliferation, invasion and migration, but inhibited apoptosis in HCC by directly targeting the 3'-UTR of PTEN. Western blots showed that miR-155-5p inactivated Bax and caspase-9, but activated Bcl-2 to inhibit apoptosis, and it activated MMP to promote migration and invasion via the PI3K/Akt pathway. A xenograft tumor model was used to demonstrate that miR-155-5p targets PTEN and activates the PI3K/Akt pathway in vivo as well. Our study highlighted the importance of miR-155-5p and PTEN associated with aggressive HCC both in vitro and in vivo.
Fu X
,Wen H
,Jing L
,Yang Y
,Wang W
,Liang X
,Nan K
,Yao Y
,Tian T
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Effects of miR-202-5p silencing PIK3CA gene expression on proliferation, invasion, and epithelial-mesenchymal transition of cervical cancer SiHa cells through inhibiting PI3K/Akt/mTOR signaling pathway activation.
To explore the mechanism of miR-202-5p targeting the expression of PIK3CA and mediating the activation of PI3K/Akt/mTOR signaling pathway on the proliferation, invasion, and epithelial-mesenchymal transition (EMT) of cervical cancer. The objects of study were 105 cases of cervical cancer and their corresponding normal tissues. qRT-PCR was used to detect the expression of miR-202-5p and PIK3CA in adjacent normal tissue and cervical cancer tissue. Dual luciferase reporter assay was used to verify the targeting relationship between miR-202-5p and PIK3CA gene. Human cervical cancer cell lines HPV-16E6, SiHa, HeLa, and CaSki were purchased for our cell experiments. The expression levels of PIK3CA in the cells were detected by qRT-PCR. The cell line with higher expression levels was selected to complete the follow-up experiment. The cultured cells were transfected and divided into the miR-202-5p mimic NC group, miR-202-5p mimic group, miR-202-5p inhibitor NC group, miR-202-5p inhibitor group, siRNA-PIK3CA NC group, siRNA-PIK3CA group, miR-202-5p inhibitor NC + siRNA-PIK3CA NC group, miR-202-5p inhibitor + siRNA-PIK3CA NC group, and miR-202-5p inhibitor + siRNA-PIK3CA group. QRT-PCR was used to detect the expression of miR-202-5p. Western blot and qRT-PCR were applied to detect the mRNA and protein expression levels of related pathway proteins (PIK3CA, PI3K, PTEN, p-Akt1, and p-mTOR) and epithelial-mesenchymal transition-related factors (N-cadherin, E-cadherin, and vimentin). Cell proliferation was detected by plate colony formation assay. Transwell assay was used to detect the invasion ability of each group. When compared with the adjacent tissues, PIK3CA mRNA expression level was significantly increased and miR-202-5p expression level was significantly decreased in cervical cancer tissues (all P < 0.05). PIK3CA was a target gene of miR-202-5p. The mRNA expression level of PIK3CA in SiHa cervical cancer cells was significantly higher than that in CaSki, HeLa, and HPV-16E6 cells (all P < 0.05), and SiHa cervical cancer cells were selected to complete the follow-up experiments. When compared with the corresponding NC group, the expression of miR-202-5p in miR-202-5p mimic group was increased. In addition, the mRNA and protein expression levels of E-cadherin and PTEN in miR-202-5p mimic and siRNA-PIK3CA groups were increased, and the protein expression of p-Akt1 and p-mTOR was decreased, and also, the mRNA and protein expression levels of PIK3CA, PI3K, N-cadherin, and vimentin were decreased (all P < 0.05); in miR-202-5p inhibitor group, the expression levels of miR-202-5p, E-cadherin, and PTEN decreased, the protein expression of p-Akt1 and p-mTOR increased, and the mRNA and protein expression of PIK3CA, PI3K, N-cadherin, and vimentin increased in miR-202-5p inhibitor group (all P < 0.05); in miR-202-5p inhibitor + siRNA-PIK3CA group, the expression of miR-202-5p decreased (P < 0.05), but the mRNA and protein expression of PIK3CA, PI3K, p-Akt1, p-mTOR, N-cadherin, E-cadherin, and vimentin had no significant changes (all P > 0.05). When compared with the corresponding NC group, the number of cell clones in miR-202-5p mimic group and siRNA-PIK3CA group was decreased, and the invasion ability of miR-202-5p inhibitor group was increased, and the invasion ability was enhanced (all P < 0.05); miR-202-5p inhibitor + siRNA-PIK3CA group showed no significant change in the number of cell clones and the rate of invasion (P > 0.05). In conclusion, the overexpression of miR-202-5p can suppress PIK3CA gene expression and the activation of PI3K/Akt/mTOR signaling pathway to suppress the proliferation, invasion, and EMT of cervical cancer.
Zheng Y
,Xie L
,Xu S
,Yan W
,Zhang H
,Meng Y
,Liu J
,Wei X
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