MTOR and neoplasm: Next, circDennd1b was found to promote the progression of pituitary tumor by sponging miR-145-5p, which acts as a tumor suppressor and downregulates the expression of one cut homobox 2, a transcription factor that participates in tumor development by regulating fibroblast growth-factor receptor 3 expression in signaling pathways such as MAPK, mammalian target of rapamycin, and phosphoinositide-3 kinase (80).