Cancer-associated fibroblasts induce PDL1+ neutrophils through the IL6-STAT3 pathway that foster immune suppression in hepatocellular carcinoma

Cell Death Dis. 2018 Apr 1;9(4):422. doi: 10.1038/s41419-018-0458-4.

Abstract

Emerging evidence indicate that cancer-associated fibroblasts (CAFs) affect tumor progression by reshaping the tumor microenvironment. Neutrophils are prominent components of solid tumors and important in cancer progression. Whether the phenotype and function of neutrophils in hepatocellular carcinoma (HCC) are influenced by CAFs is not well understood. Herein, we investigated the effect of HCC-derived CAFs (HCC-CAFs) on the neutrophils and explored the biological role of this effect. We found that HCC-CAFs induced chemotaxis of neutrophils and protected them from spontaneous apoptosis. Neutrophils were activated by the conditioned medium from HCC-CAFs with increased expression of CD66b, PDL1, IL8, TNFa, and CCL2, and with decreased expression of CD62L. HCC-CAF-primed neutrophils impaired T-cell function through the PD1/PDL1 signaling pathway. We revealed that HCC-CAFs induced the activation of STAT3 pathways in neutrophils, which are essential for the survival and function of activated neutrophils. In addition, we demonstrated that HCC-CAF-derived IL6 was responsible for the STAT3 activation of neutrophils. Collectively, our results suggest that HCC-CAFs regulate the survival, activation, and function of neutrophils within HCC through an IL6-STAT3-PDL1 signaling cascade, which presents a novel mechanism for the role of CAFs in remodeling the cancer niche and provides a potential target for HCC therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, CD / genetics
  • Antigens, CD / metabolism
  • B7-H1 Antigen / metabolism*
  • Cancer-Associated Fibroblasts / cytology
  • Cancer-Associated Fibroblasts / metabolism
  • Carcinoma, Hepatocellular / pathology
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / metabolism
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Chemokine CXCL12 / genetics
  • Chemokine CXCL12 / metabolism
  • Culture Media, Conditioned / pharmacology
  • GPI-Linked Proteins / genetics
  • GPI-Linked Proteins / metabolism
  • Humans
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism
  • Liver Neoplasms
  • Neutrophil Activation / drug effects
  • Neutrophils / cytology
  • Neutrophils / drug effects
  • Neutrophils / metabolism*
  • STAT3 Transcription Factor / metabolism
  • Signal Transduction* / drug effects
  • T-Lymphocytes / cytology
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Antigens, CD
  • B7-H1 Antigen
  • CD274 protein, human
  • CEACAM8 protein, human
  • Cell Adhesion Molecules
  • Chemokine CXCL12
  • Culture Media, Conditioned
  • GPI-Linked Proteins
  • Interleukin-6
  • STAT3 Transcription Factor
  • STAT3 protein, human
  • Tumor Necrosis Factor-alpha