Expression Of Hsa_circ₀077837 In Bladder Cancer And Its Effect On Cell Malignancy

Purpose: 1.For five pairs of bladder cancer（BCa）tissues and adjacent normal tissues,we identified differential expressed circRNAs by the high-throughput circRNAs sequencing and bioinformatics analysis.Through construction of a network of ceRNAs related to these circRNAs,we predicted and discussed its potentially relevant molecular mechanisms.Next,the significantly differential expressed hsa_circ₀077837 were screened for conducting subsequent verification of PCR.2.Based on RT-qPCR experiment,We performed expression confirmation of hsa_circ₀077837;and thereof explored its relevance with the clinicopathological features,clinical survival or recurrence prognosis of patients with bladder cancer.Then,we investigated the effects of hsa_circ₀077837 on the proliferation,migration and invasion of bladder cancer cells by in vitro experiments.Method: 1.Five pairs of BCa tissues and adjacent normal tissues were collected for high-throughput RNA sequencing,and then the biomarker technology was used to analyze the significantly different circRNAs profiles of cancer tissues compared with adjacent tissues.Hsa_circ₀077837 was subsequently selected and verified by RT-qPCR in 70 matched other specimens.Afterwards,according to the above validation data,basic clinical information and follow-up information of BCa patients,Fisher’s exact test,ROC curve,Kaplan Meier survival curve 、 univariate and multivariate COX regression analysis was performed to clarify its clinical significance.2.The expression level of hsa_circ₀077837 was identified by RT-qPCR in BCa cell lines（EJ,5637,T24,253J-BV）and human immortalized urothelial cells（SV-HUC-1）.Then,EJ and 253J-BV cells transfected using circ₀077837 lentiviral vector or control empty vector.And,the effects of hsa_circ₀077837 on the proliferation,migration,and invasion of BCa cells was tested using colony formation experiments,CCK-8 experiments,scratch experiments,and transwell migration and invasion experiments.Result: 1.Based on high-throughput RNA sequencing of 5 pairs of tissues and RT-qPCR verification of 70 pairs of tissues,it was shown that the expression of hsa_circ₀077837 in BCa tissues was significantly lower than that in adjacent normal tissues（P<0.0001）;Fisher’s test exhibited that its significant low expression was associated with poor clinicopathological features of BCa patient（P<0.05）;ROC curve analysis suggests it could be a potential biomarker for diagnosing BCa patients;Kaplan Meier survival curve and COX regression analysis confirmed that its low expression was significantly correlated with poor survival or recurrence prognosis（P<0.05）.Finally,59 mi RNAs and 227 m RNAs were established in the ceRNA network.2.Colony formation experiments and CCK-8 experiments demonstrated that overexpression of hsa_circ₀077837 could significantly reduce the proliferation of EJ and 253J-BV cells;Cell scratch test and transwell migration experiment showed that over-expression hsa_circ₀077837 could significantly inhibit the migration ability of EJ,253J-BV cells;Transwell invasion experiments confirmed that overexpression of hsa_circ₀077837 could significantly weaken the invasion ability of EJ and 253J-BV cells.Conclusion: hsa_circ₀077837 was significantly down-regulated in BCa tissues,and its down-regulation was significantly associated with adverse pathological characteristics and shorter survival or recurrence prognosis of BCa patients.In addition,in vitro experiments showed that overexpression of hsa_circ₀077837 can significantly receded the proliferation,migration,and invasion of BCa cells.The insight analysis for hsa_circ₀077837 mediating the deveopment and progression of BCa through mechanism of ceRNA was performed.