ABSTRACT
MicroRNA-34a (miR-34a) serves as a tumor suppressor in a number of different types of cancer. The present study was performed to investigate the involvement of miR-34a in bladder cancer. In the present study, miR-34a was downregulated in patients with bladder cancer compared with the healthy controls in bladder biopsies and plasma. Downregulation of miR-34a distinguished between patients with bladder cancer and the healthy controls. miR-34a expression was associated with tumor metastasis; however, not with tumor size. Transfection of miR-34a mimics upregulated the expression of phosphatase and tensin homolog (PTEN) in bladder cancer cells, and decreased cell migration and invasion. miR-34a may inhibit bladder cancer cell migration and invasion by upregulating PTEN. miR-34a may additionally serve as a potential therapeutic target for bladder cancer.
ABSTRACT
AIM: To explore the molecular mechanism of nonmuscle invasive bladder cancer (NMIBC), matched normal, and cancer tissues of 10 NMIBC were examined for RNA sequencing. METHODS: We profiled the messenger RNA (mRNA) and long noncoding RNA (lncRNA) expression of patients with NMIBC. Differentially expressed mRNAs and lncRNAs were screened between cancer and normal tissues and validated by quantitative polymerase chain reaction (qPCR), and lncRNA-mRNA-miRNA interaction network was constructed. RESULTS: A total of 91 upregulated and 190 downregulated genes and 34 upregulated and 58 downregulated lncRNAs were screened from the sequencing result. The differentially expressed mRNAs were enriched in focal adhesion, rap1 signaling pathway, Hippo signaling pathway, PI3K-Akt signaling pathway, extracellular matrix (ECM)-receptor interaction, Ras signaling pathway, and mitogen-activated protein kinases signaling pathway, of which some pathways were involved in the cancer development. In the RNA sequencing, KIT and laminin subunitγ γ3 (LAMC3) were significantly downregulated in the NMIBC group compared with the normal group. The results of quantitative reverse transcription PCR showed that the expression of LAMC3 and KIT were significantly decreased in the NMIBC group compared with the normal group. The lncRNA-mRNA-miRNA interaction network was constructed by Cytoscape software to further investigate the interaction correlations. The results implied that KIT and LAMC3 might regulate the lncRNAs (such as ENST00000445707, ENST00000501122, ENST00000505254, ENST00000528986, ENST00000557661, ENST00000602964, ENST00000614517, ENST00000620864, and ENST00000623414) by the miRNAs (such as hsa-let-7f-2-3p, hsa-miR-125a-3p, hsa-miR-134-3p, hsa-miR-191-5p, hsa-miR-210-5p, hsa-miR-30a-5p, hsa-miR-30d-5p, hsa-miR-30e-5p, hsa-miR-92a-2-5p, and hsa-miR-95-3p), and finally played a role in the development of NMIBC cancer. CONCLUSION: Altogether, our study preliminarily indicated that KIT and LAMC3 might play a crucial role in the development of NMIBC cancer via a complex mRNA-lncRNA-miRNA regulatory network.
