Myosin II Reactivation and Cytoskeletal Remodeling as a Hallmark and a Vulnerability in Melanoma Therapy Resistance

Cancer Cell. 2020 Jan 13;37(1):85-103.e9. doi: 10.1016/j.ccell.2019.12.003.

Abstract

Despite substantial clinical benefit of targeted and immune checkpoint blockade-based therapies in melanoma, resistance inevitably develops. We show cytoskeletal remodeling and changes in expression and activity of ROCK-myosin II pathway during acquisition of resistance to MAPK inhibitors. MAPK regulates myosin II activity, but after initial therapy response, drug-resistant clones restore myosin II activity to increase survival. High ROCK-myosin II activity correlates with aggressiveness, identifying targeted therapy- and immunotherapy-resistant melanomas. Survival of resistant cells is myosin II dependent, regardless of the therapy. ROCK-myosin II ablation specifically kills resistant cells via intrinsic lethal reactive oxygen species and unresolved DNA damage and limits extrinsic myeloid and lymphoid immunosuppression. Efficacy of targeted therapies and immunotherapies can be improved by combination with ROCK inhibitors.

Keywords: MAPK; Rho-kinase; cytoskeletal remodeling; immunotherapy; melanoma therapy resistance; myosin II; phosphoproteomics and transcriptomics; regulatory T cells; transcriptional rewiring; tumor-promoting macrophages.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • B7-H1 Antigen / metabolism
  • Cell Cycle
  • Cell Line, Tumor
  • Cytoskeleton / metabolism*
  • DNA Damage
  • Drug Resistance, Neoplasm*
  • Female
  • Humans
  • Immunotherapy
  • MAP Kinase Signaling System
  • Male
  • Melanoma / immunology
  • Melanoma / metabolism*
  • Melanoma / therapy
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred NOD
  • Mice, Nude
  • Mice, SCID
  • Myosin Type II / metabolism*
  • Oxidative Stress
  • Protein Kinase Inhibitors / pharmacology
  • Proto-Oncogene Proteins B-raf / genetics
  • Reactive Oxygen Species
  • T-Lymphocytes, Regulatory / immunology
  • Treatment Outcome
  • Tumor Microenvironment / immunology
  • rho-Associated Kinases / metabolism

Substances

  • B7-H1 Antigen
  • CD274 protein, human
  • Protein Kinase Inhibitors
  • Reactive Oxygen Species
  • Proto-Oncogene Proteins B-raf
  • rho-Associated Kinases
  • Myosin Type II