SOCS1 favors the epithelial-mesenchymal transition in melanoma, promotes tumor progression and prevents antitumor immunity by PD-L1 expression

Sci Rep. 2017 Jan 12:7:40585. doi: 10.1038/srep40585.

Abstract

Silencing of SOCS1 protein with shRNAi lentivirus (shR-SOCS1) led to partial reversion of the tumorigenic phenotype of B16F10-Nex2 melanoma cells. SOCS1 silencing inhibited cell migration and invasion as well as in vitro growth by cell cycle arrest at S phase with increased cell size and nuclei. Down-regulation of SOCS1 decreased the expression of epidermal growth factor receptor, Ins-Rα, and fibroblast growth factor receptors. The present work aimed at analyzing the SOCS1 cell signaling and expression of proteins relevant to tumor development. An RNA microarray analysis of B16F10-Nex2 melanoma cells with SOCS1 silenced by shRNAi-SOCS1 was undertaken in comparison with cells transduced with the empty vector. Among 609 differentially expressed genes, c-Kit, Met and EphA3 cytokine/tyrosine-kinase (TK) receptors were down regulated. A significant decrease in the expression of TK receptors, the phosphorylation of mediators of ERK1/2 and p38 pathways and STAT3 (S727) were observed. Subcutaneous immunization with shR-SOCS1-transduced viable tumor cells rendered protection against melanoma in a syngeneic model, with decreased expression of PD-L1 and of matrix metallo-proteinases (MMPs) and CD-10 in those cells. The present work shows the role of SOCS1 in murine melanoma development and the potential of SOCS1-silenced tumor cells in raising an effective anti-melanoma immune response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • B7-H1 Antigen / metabolism*
  • Bone Morphogenetic Protein Receptors, Type I / metabolism
  • Bone Morphogenetic Proteins / metabolism
  • CD8-Positive T-Lymphocytes / immunology
  • Cyclic AMP Response Element-Binding Protein / metabolism
  • Disease Progression*
  • Epithelial-Mesenchymal Transition* / genetics
  • Gene Expression Regulation, Neoplastic
  • Gene Silencing
  • Immunity*
  • Melanoma, Experimental / genetics
  • Melanoma, Experimental / immunology*
  • Melanoma, Experimental / pathology*
  • Melanoma-Specific Antigens / metabolism
  • Mice, Inbred C57BL
  • NF-kappa B / metabolism
  • Protective Agents / metabolism
  • Receptor Protein-Tyrosine Kinases / metabolism
  • Signal Transduction
  • Smad Proteins / metabolism
  • Suppressor of Cytokine Signaling 1 Protein / metabolism*
  • Transcription Factor AP-2 / metabolism
  • Transcription, Genetic
  • Transforming Growth Factor beta / metabolism
  • Tumor Microenvironment
  • Up-Regulation / genetics

Substances

  • B7-H1 Antigen
  • Bone Morphogenetic Proteins
  • Cd274 protein, mouse
  • Cyclic AMP Response Element-Binding Protein
  • Melanoma-Specific Antigens
  • NF-kappa B
  • Protective Agents
  • Smad Proteins
  • Socs1 protein, mouse
  • Suppressor of Cytokine Signaling 1 Protein
  • Transcription Factor AP-2
  • Transforming Growth Factor beta
  • Receptor Protein-Tyrosine Kinases
  • Bmpr1a protein, mouse
  • Bone Morphogenetic Protein Receptors, Type I