For instance, circPTPRA impedes the epithelial-mesenchymal transition and metastasis of NSCLC cells [27]; circ_ARHGAP10 promotes the progression of NSCLC by up-modulating GLUT-1 expression, and its overexpression indicates the unfavorable prognosis of NSCLC patients [28]; circ_100395 inhibits the malignant phenotypes of lung cancer cells via modulating TCF21 expression [29]. The gene discussed is TCF21; the disease is lung carcinoma.