Background Laryngeal cancer has the highest mortality rate among head and neck tumours. RNA N6-methyladenosine (m6A) is the most plentiful and variable in mammalian mRNA. Yet, the m6A regulatory mechanism underlying the carcinogenesis or progression of LSCC remains poorly understood. Methods The m6A RNA methylation quantification kit was used to detect tissue methylation levels. m6A microarray analysis, mRNA transcriptomic sequencing (mRNA-seq), and proteomics were used to determine RBM15, TMBIM6, and IGF2BP3. Immunohistochemical (IHC), quantitative real-time PCR (qRT-PCR) and Western blot were used to investigate RBM15, TMBIM6, and IGF2BP3 expression in tissue samples and cell lines. The biological effects of RBM15 were detected both in vitro and in vivo. The combination relationship between RBM15/IGF2BP3 and TMBIM6 was verified by RNA immunoprecipitation (RIP) assay, Methylated RNA immunoprecipitation sequencing (MeRIP-seq), RNase Mazf, and luciferase report assay. RNase Mazf was used to determine the methylation site on TMBIM6 mRNA. Hoechst staining assay was used to confirm the apoptotic changes. The actinomycin D verified TMBIM6 stability. Results The global mRNA m6A methylation level significantly increased in LSCC patients. RBM15, as a “writer” of methyltransferase, was significantly increased in LSCC and was associated with unfavorable prognosis. The knockdown of RBM15 reduced the proliferation, invasion, migration, and apoptosis of LSCC both in vitro and in vivo. The results were reversed after overexpressing RBM15. Mechanically, TMBIM6 acted as a downstream target of RBM15-mediated m6A modification. Furthermore, RBM15-mediated m6A modification of TMBIM6 mRNA enhanced TMBIM6 stability through IGF2BP3-dependent. Conclusion Our results revealed the essential roles of RBM15 and IGF2BP3 in m6A methylation modification in LSCC, thus identifying a novel RNA regulatory mechanism.

Laryngeal squamous cell carcinoma (LSCC) is the most common pathological subtype (>95%) of laryngeal carcinoma. 1,2 The prevalence of LSCC was ranked as 2nd in head and neck squamous cell carcinoma (HNSCC). It is reported that in 2018, there were 177,422 new cases of LSCC and 94,771 deaths of LSCC in the world. 3 Notably, the incidence of LSCC in China is about four times that in the United States, with an estimated death toll of more than 15,000 per year. 4 The 5-year overall survival (OS) rate of patients with advanced LSCC is lower than 50%. 5 Therefore, we urgently need to have a deeper understanding of the mechanism that promotes LSCC progression. N6-methyladenosine (m6A) as a major internal modification of RNA in higher eukaryotes has aroused great interest in recent years. [6][7][8] The researchers suggested that the m6A methylation plays an important role in the regulation of gene expression by influencing RNA stability, mRNA degradation and translation. 9,10 This modification mainly depends on the dynamic regulation of RNA

Laryngeal cancer, more than 95% of which are squamous cell carcinomas (SCC), is the second most common malignant neoplasm in head and neck. Its incidence has remarkably increased over the recent years due to the high smoking rates, industrialization and ageing. 1,2 Despite considerable progress in surgical techniques, as well as chemotherapy and radiotherapy, the prognosis of advanced laryngeal cancer remains poor. [3][4][5] Also, the exact molecular mechanisms underlying the carcinogenesis or progression of LSCC remain poorly

Long non-coding RNAs (lncRNAs) play important roles in various biological progresses of carcinogenesis. However, the function of lncRNAs in human sinonasal squamous cell carcinoma (SNSCC) remains greatly unclear. In the current study, lncRNA AC091729.7 expression was examined in SNSCC samples by using microarray, RNA in situ hybridization (ISH) and real-time fluorescence quantitative PCR (qRT-PCR). Cell viability, colony-formation, wound-healing, and transwell assays were applied to SNSCC cells. Xenograft mouse models were employed to evaluate the role of AC091729.7 in growth of SNSCC in vivo. Human protein microarray (Huprot TM Protoarray) and RNA immunoprecipitation (RIP) were used for identifying AC091729.7 binding proteins in SNSCC. Results showed AC091729.7 was upregulated and closely connected with the survival of the SNSCC patients. Knockdown of AC091729.7 suppressed SNSCC cell migration, proliferation, invasion in vitro. Furthermore, downregulation of AC091729.7 could inhibit the growth of SNSCC in vivo. Moreover, Human protein microarray and RIP suggested that AC091729.7 directly combine with the serine/arginine rich splicing factor 2 (SRSF2). Our results suggest that in the cell progression of SNSCC, lncRNA AC091729.7 plays a carcinogenic role and serves as a novel biomarker and latent curative target in SNSCC patients.

Background Nasopharyngeal carcinoma (NPC) is a deadly cancer, mainly presenting in southeast and east Asia. Long noncoding RNAs (lncRNAs) play essential roles in cancer progression. Exosomes are critical for intercellular communication. Thus, the aim of this study was to identify the functional lncRNAs in NPC and its relevant mechanisms. Methods Data from public databases were utilized to screen for functional lncRNAs in NPC. Functional and mechanical experiments were performed to determine the role of lncRNAs in NPC and its relative molecular mechanisms. Exosomes derived from NPC cells were isolated to determine their function in tumor-associated macrophages. Results LncRNA TP73-AS1 was increased in NPC cells and tissues and was associated with a poor prognosis. TP73-AS1 overexpression promoted proliferation, colony formation, and DNA synthesis of NPC cells while TP73-AS1 knockdown showed opposite roles. TP73-AS1 could directly bind with miR-342-3p. MiR-342-3p overexpression attenuated the effect of TP73-AS1 in NPC cells. Furthermore, TP73-AS1 was transferred by exosomes to promote M2 polarization of macrophages. Lastly, exosomal TP73-AS1 enhanced the motility and tube formation of macrophages. Conclusions Together, this study suggests that TP73-AS1 promotes NPC progression through targeting miR-342-3p and exosome-based communication with macrophages and that TP73-AS1 might be an emerging biomarker for NPC.