Background Circular RNAs (circRNAs) are implicated in the development of oral squamous cell carcinoma (OSCC). The aim of current research is to elucidate the role and mechanism of circ_0011946 in the functional behaviors of OSCC cells. Methods Circ_0011946, microRNA (miR)-216a-5p, B cell lymphoma-2-like 2 protein (BCL2L2) abundances were exposed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) or western blot. Cell proliferation, migration, invasion and apoptosis were detected by MTT, colony formation assay, transwell, wound-healing and flow cytometry assays, respectively. Target correlation was tested by dual-luciferase reporter and RNA pull-down assays. An in vivo xenograft experiment was employed to investigate the function of circ_0011946 on tumor growth in vivo. Results Circ_0011946 and BCL2L2 levels were increased, while miR-216a-5p level was decreased in OSCC tissues and cells. Circ_0011946 knockdown impeded proliferation, migration, and invasion, but promoted apoptosis in OSCC cells. Circ_0011946 functioned as a sponge for miR-216a-5p, and BCL2L2 was targeted by miR-216a-5p. Besides, miR-216a-5p or BCL2L2 knockdown partly attenuated the inhibitory influences of circ_0011946 silence or miR-216a-5p overexpression on OSCC cell progression. Furthermore, circ_0011946 post-transcriptionally regulated BCL2L2 through sponging miR-216a-5p. Moreover, circ_0011946 knockdown constrained OSCC tumor growth in vivo. Conclusion Circ_0011946 silence repressed OSCC cell proliferation, migration, and invasion, but promoted apoptosis through the regulation of the miR-216a-5p/BCL2L2 axis.

During OP bone metabolism, activated MAPK signaling can promote the proliferation and differentiation of osteoclasts. miRNAs involve in bone diseases. Our study aimed to evaluate miR-200c’s effect on ERK/MAPK signaling pathway in OP. miR-200c expression in OP mice and normal mice was detected by qPCR. BMSCs were cultured and transfected with siRNA to establish a miR-200c knockout model. Flow cytometry was used to detect cell apoptosis and ERK/MAPK signaling protein was detected by Western blot. miR-200c expression in OP mice was significantly lower than that in normal mice. Bone marrow mesenchymal stem cells (BMSCs) contain a large amount of siRNA particles under a fluorescence microscope. siRNA transfection can effectively inhibit miR-200c expression without difference of BMSCs apoptosis between miR-200c siRNA group and NC group. However, ERK1/2 and P38 expression in experimental group were significantly higher than those in NC siRNA group with reduced ALP activity. In addition, BMSCs osteogenic differentiation was further diminished when miR-200c expression was inhibited. miR-200c expression is lower in OP mice. miR-200c siRNA inhibits BMSCs osteogenic differentiation via ERK/MAPK signaling, thereby promoting OP progression.