Critical roles of the long noncoding RNA SNHG4 in human cancers

Cancer remains a major cause of morbidity and mortality worldwide, with its incidence and mortality rates continuing to rise. The long noncoding RNA SNHG4, a member of the small nucleolar RNA host gene family, has emerged as a candidate regulator in human cancers. This review synthesizes the currently reported expression patterns and clinical significance of SNHG4 across various malignancies, including colorectal cancer, hepatocellular carcinoma, gastric cancer, glioblastoma, prostate cancer, and lung cancer. Particular attention is given to tissue-dependent expression reversals, differences in evidence strength, and unresolved translational barriers. Additionally, this review describes the molecular mechanisms through which SNHG4 modulates oncogenic processes, including promoting cancer cell proliferation, migration, invasion, and epithelial‒mesenchymal transition and inhibiting apoptosis and ferroptosis. In summary, this review highlights the vital role of SNHG4 in cancer biology and critically evaluates its potential diagnostic and prognostic value together with the barriers to developing SNHG4-directed therapies. Despite these promising findings, the current evidence is largely derived from retrospective studies and preclinical models. Further large-scale, prospective multicenter studies with standardized detection methods are critically needed to validate the translational potential of SNHG4 before it can be considered for clinical application.