Regulation of laryngeal squamous cell cancer progression by the lncRNA RP11‐159K7.2/miR‐206/DNMT3A axis

: Long non-coding RNAs (lncRNAs), which are longer than 200 nt, have been proved to play a role in promoting or inhibiting cancer progression. The following study investigated the role and underlying mechanisms of lncRNA RP11-159K7.2 in laryngeal squamous cell carcinoma (LSCC) progression. Briefly, in situ hybridization (ISH) and real-time quantitative PCR (RT-qPCR) showed higher expression of RP11-159K7.2 in LSCC tissues and cell lines. Patients with low expression level of RP11-159K7.2 lived longer compared to those with high expression of RP11-159K7.2 (χ2  = 39.111, ***P < 0.001). Multivariate Cox regression analysis suggested that lncRNA RP11-159K7.2 was an independent prognostic factor for LSCC patients (HR = 2.961, ***P < 0.001). Furthermore, to investigate the potential involvement of RP11-159K7.2 in the development of LSCC, we knocked out the expression of endogenous RP11-159K7.2 in TU-212 cells and AMC-HN-8 cells via CRISPR/Cas9 double vector lentiviral system. RP11-159K7.2 knockout decreased LSCC cell growth and invasion both in vitro and in vivo. Mechanically, we found that RP11-159K7.2 could positively regulate the expression of DNMT3A by sponging miR-206. In addition, a feedback loop was also discovered between DNMT3A and miR-206. To sum up, these findings suggest that lncRNA RP11-159K7.2 could be used as a potential biomarker for prognosis and treatment of LSCC.