Journal of Experimental & Clinical Cancer Research (May 2022)

Interleukin-6 mediated inflammasome activation promotes oral squamous cell carcinoma progression via JAK2/STAT3/Sox4/NLRP3 signaling pathway

  • Li Xiao,
  • Xue Li,
  • Peilin Cao,
  • Wei Fei,
  • Hao Zhou,
  • Na Tang,
  • Yi Liu

DOI
https://doi.org/10.1186/s13046-022-02376-4
Journal volume & issue
Vol. 41, no. 1
pp. 1 – 20

Abstract

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Abstract Background Interleukin-6 (IL-6) has been reported to be critical in oral squamous cell carcinoma (OSCC). However, the set of pathways that IL-6 might activate in OSCC are not fully understood. Methods IL-6 and Sox4 expressions were first determined with RT-qPCR, ELISA, Western blot, or immunohistochemistry in OSCC tissues, and correlations between IL-6 and Sox4 expression and patient pathological characteristics were examined, and Kaplan–Meier approach was employed for evaluating the prognostic utility in OSCC patients. CCK-8, EdU stain and colony formation assays were utilized to test cell proliferation in vitro. Mechanistically, downstream regulatory proteins of IL-6 were verified through chromatin immunoprecipitation, luciferase reporter, pull-down, and the rescued experiments. Western blot was used for detecting protein expression. A nude mouse tumorigenicity assay was used to confirm the role of IL-6 and Sox4 in vivo. Results IL-6 was upregulated in OSCC tissues, and Sox4 expression was positively correlated with IL-6 expression. High IL-6 and Sox4 expression was closely related to tumor size, TNM stage, and a poorer overall survival. Besides, IL-6 could accelerate OSCC cell proliferation by activating inflammasome via JAK2/STAT3/Sox4/NLRP3 pathways in vitro and in vivo. Furthermore, STAT3 played as a transcription factor which positively regulated Sox4, and IL-6 promotes Sox4 expression by activating JAK2/STAT3 pathway. Moreover, through the rescue experiments, we further confirmed that IL-6 could promote proliferation and NLRP3 inflammasome activation via JAK2/STAT3/Sox4 pathway in OSCC cells. Finally, knockdown of Sox4 suppressed OSCC growth in vivo, and antagonized the acceleration of IL-6 on tumor growth. Conclusions We confirmed that IL-6 plays an oncogenic role in OSCC progression by activating JAK2/STAT3/Sox4/NLRP3 pathway, which might be the therapeutic targets for OSCC remedy.

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