METTL3 mediated WISP1 m6A modification promotes epithelial-mesenchymal transition and tumorigenesis in laryngeal squamous cell carcinoma via m6A reader IGF2BP1.

Object: N6-methyladenosine (m⁶A), is well known as the most abundant epigenetic modification in messenger RNA, but its influence on laryngeal squamous cell carcinoma (LSCC) remains largely unexplored and poorly understood. This study was designed to explore the effects of m⁶A on WISP1-mediated epithelial-mesenchymal transition (EMT) and tumorigenesis in LSCC.

Methods: m⁶A methylated and expression levels of WISP1 in LSCC tumor tissues and cells were measured by MeRIP-qPCR, qRT-PCR, and western blotting. The regulatory mechanism of m⁶A modification of WISP1 in LSCC was determined using MeRIP-qPCR, RIP, dual luciferase reporter assay, and RNA stability assay. Cell viability was assessed utilizing MTT method. The invasion and migration ability of LSCC cells were determined by transwell and wound healing method, respectively. Tumor xenograft models were used for the in vivo experiments.

Results: The m⁶A methylation level of WISP1 was significantly enhanced in LSCC patients and LSCC cell lines. Overexpression of the m⁶A methyltransferase METTL3 significantly upregulated WISP1 expression by promoting its m⁶A methylation level, whereas METTL3 inhibition exhibited the opposite effect in LSCC cells. Functionally, we found that METTL3 accelerated the viability, invasion, migration, and EMT of LSCC cells by upregulating WISP1. Additionally, overexpression of METTL3 increased WISP1 expression and tumorigenesis were verified in in vivo experiments. Mechanistically, m⁶A-modified WISP1 was recognized by IGF2BP1, which enhanced the stability of WISP1 mRNA.

Conclusion: Our findings indicate that the m⁶A modification of WISP1 promotes EMT in LSCC by enhancing WISP1 mRNA stability via an IGF2BP1-dependent manner, which may highlight an m⁶A methylation-based approach for LSCC diagnosis and therapy.