Lyu K, Xu Y, Yue H, et al. - The critical roles and biological function of long noncoding RNAs (lncRNAs) growth arrest-specific 5 (GAS5) in tumorigenesis of laryngeal squamous cell carcinoma (LSCC) were investigated via assessing a total of 59 samples of LSCC and paired adjacent tissue, as well as corresponding clinicopathological information. Using Real-time quantitative RT-PCR method, researchers analyzed GAS5 expression in both LSCC tissues and human SUN1076 and SNU899 cell lines. The critical roles and function of GAS5 in LSCC were determined via assessing the ectopic expression of GAS5 by vector transfection in LSCC cell lines, which was followed by in vitro experiments. Outcomes revealed significant downregulation of GAS5 in LSCC tissue and human LSCC cell lines. Via the negative regulation of miR-21 and its targets involved in cell proliferation and apoptosis, GAS5 led to the suppression of LSCC progression. This indicates the possible value of GAS5 as a biomarker and potential target for LSCC therapy.