Kaohsiung Journal of Medical Sciences (Nov 2022)

Cancer‐associated fibroblast‐secreted miR‐421 promotes pancreatic cancer by regulating the SIRT3/H3K9Ac/HIF‐1α axis

  • Bin Zhou,
  • Jing‐Hao Lei,
  • Qiang Wang,
  • Teng‐Fei Qu,
  • Li‐Chao Cha,
  • Han‐Xiang Zhan,
  • Shang‐Long Liu,
  • Xiao Hu,
  • Chuan‐Dong Sun,
  • Wei‐Dong Guo,
  • Fa‐Bo Qiu,
  • Jing‐Yu Cao

DOI
https://doi.org/10.1002/kjm2.12590
Journal volume & issue
Vol. 38, no. 11
pp. 1080 – 1092

Abstract

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Abstract This study was designed to explore the effects of exosomal miR‐421 secreted by cancer‐associated fibroblasts (CAFs) on pancreatic cancer (PC) progression and the mechanisms involved. CAFs and exosomes (exos) were isolated and identified. PC cells were treated with CAF‐derived exos (CAF‐exos). Western blotting and quantitative polymerase chain reaction (qPCR) were used to measure miR‐421, sirtuin‐3 (SIRT3), and hypoxia duciblefactors‐1 alpha (HIF‐1α) levels. Cell counting kit‐8 (CCK‐8), wound‐healing, and transwell migration assays were used to measure proliferation, migration, and invasion abilities of the cells. Dual‐luciferase assay and RNA immunoprecipitation (RIP) experiment analyzed the relationship between miR‐421 and SIRT3. Chromatin immunoprecipitation (f)‐verified H3K9Ac enrichment in the HIF‐1α promoter region. In vivo tumorigenesis experiments were performed to further explore the effects of exosomal miR‐421 from CAFs on PC. CAFs and exos were successfully isolated. CAF‐exo‐treated PC cells highly expressed miR‐421 and had increased cell proliferation, migration, and invasion abilities. Knocking down miR‐421 increased the expression of SIRT3. SIRT3 is a target of miR‐421, and inhibiting the expression of SIRT3 reversed the negative effects of miR‐421 knockdown on PC cell. Knocking down miR‐421 in CAF‐exo inhibited the expression of HIF‐1α in PC cells. Moreover, SIRT3‐mediated HIF‐1α expression by regulating H3K9Ac. HIF‐1α overexpression reversed the inhibiting effects of SIRT3 overexpression on PC progression and counteracted the inhibiting effects of miR‐421 knockdown on glycolysis. Moreover, in vivo tumorigenesis experiments showed that knocking down miR‐421 attenuated CAF‐exo induced tumor growth. Exosomal miR‐421 from CAFs promoted PC progression by regulating the SIRT3/H3K9Ac/HIF‐1α axis. This study provided insights into the molecular mechanism of PC.

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