circSPECC1 promotes bladder cancer progression via regulating miR-136-5p/GNAS axis

An increasing body of evidence suggest that circRNAs modulate various gene expression at the posttranscriptional level, affecting the development of cancers. Previous study suggested that circSPECC1 acted as an oncogene in some tumors, promoting the growth and metastasis of cancer cells. However, the role of circSPECC1 in bladder cancer (Bca) remains unknown.

RT-qPCR assay was applied to detect the expresion level of circRNA, miRNA and mRNA in Bca tissues and cells. CCK-8, cell colony formation and wound-healing assay were peformed to detect the effect of circSPECC1 on cell proliferation and migration. Nuclear mass separation, dual-luciferase reporter and RNA pull-down assay were used to investigate the molecular mechanisms underlying circSPECC1.

In this study, we found that circSPECC1 was significantly up-regulated in Bca tissues and cell lines. Increased expression of circSPECC1 contribute to poor prognosis of Bca. Further tests showed that knockdown of circSPECC1 impaired the proliferation and migration of Bca cells. Mechanically, circSPECC1 sponged miR-136-5p to promote the mRNA and protein expression of GNAS. Besides, enforced expression of GNAS significantly reversed the proliferation and migration inhibition mediated by circSPECC1 suppression.

In general, our study suggested that circSPECC1 contributed to the growth and metastasis of Bca and it is possible to become an ideal non-invasive biomarker for diagnosis and effective therapeutic target for treatment.