AIM2 promotes the progression of HNSCC via STAT1 mediated transcription and IL-17/MAPK signaling

Abstract

Chronic inflammation has been recognized as one of the hallmarks of head and neck squamous cell carcinoma (HNSCC), Absent In Melanoma 2(AIM2) has emerged as important regulators of chronic inflammatory, and participated in initiation, progression of kinds of human cancers. Nonetheless, the biological functions and underlying mechanisms of AIM2 in HNSCC remain inadequately understood. Based on the bioinformatics analysis of public databases, we identified elevated AIM2 expression in HNSCC, which positively correlates with disease stage and HPV infection, thereby possessing both diagnostic and prognostic significance. Immunohistochemistry on clinical samples revealed that AIM2 expression was frequently upregulated in cancerous tissues compared to paracancerous tissues, exhibiting a significant association with Ki-67 expression. Modulating AIM2 expression in HNSCC cell lines through transfection with inhibitors or mimics demonstrated that ectopic AIM2 expression enhances cell growth, migration, tumorigenesis, and metastasis both in vitro and in vivo. A dual luciferase reporter assay indicated that the transcription factor STAT1 can bind directly to the AIM2 promoter region and activate its transcription. The STAT1 inhibitor, fludarabine, reduces AIM2 expression and subsequently diminishes cell proliferation. Mechanistically, AIM2 exerts its tumor-promoting effects through the IL-17-MAPK signaling pathway. Collectively, our data demonstrate that AIM2, transcriptionally activated by STAT1, exhibits oncogenic functions by promoting the IL-17-MAPK signaling pathway, suggesting that AIM2 may be a new intervention targets for the diagnostic and treatment of HNSCC.