SNHG4 and non-small cell lung carcinoma: Interestingly, many studies have uncovered that the effects of several lncRNAs on NSCLC are associated with p21 signaling.31, 32, 33 Furthermore, as a crucial sensor of anti-proliferative signals, p21 exhibits paradoxical tumor-promoting activities in different cancers,34 implying that lncRNA SNHG4 might play a role in other cancers by mediating the p21 pathway.