MYC Induces Immunotherapy and IFNγ Resistance Through Downregulation of JAK2

Autor: Ettai Markovits, Ortal Harush, Erez N. Baruch, Eldad D. Shulman, Assaf Debby, Orit Itzhaki, Liat Anafi, Artem Danilevsky, Noam Shomron, Guy Ben-Betzalel, Nethanel Asher, Ronnie Shapira-Frommer, Jacob Schachter, Iris Barshack, Tamar Geiger, Ran Elkon, Michal J. Besser, Gal Markel
Rok vydání: 2023
Předmět:
Zdroj: Cancer Immunology Research. :OF1-OF16
ISSN: 2326-6074
2326-6066
DOI: 10.1158/2326-6066.cir-22-0184
Popis: Immunotherapy has revolutionized the treatment of advanced melanoma. Because the pathways mediating resistance to immunotherapy are largely unknown, we conducted transcriptome profiling of preimmunotherapy tumor biopsies from patients with melanoma that received PD-1 blockade or adoptive cell therapy with tumor-infiltrating lymphocytes. We identified two melanoma-intrinsic, mutually exclusive gene programs, which were controlled by IFNγ and MYC, and the association with immunotherapy outcome. MYC-overexpressing melanoma cells exhibited lower IFNγ responsiveness, which was linked with JAK2 downregulation. Luciferase activity assays, under the control of JAK2 promoter, demonstrated reduced activity in MYC-overexpressing cells, which was partly reversible upon mutagenesis of a MYC E-box binding site in the JAK2 promoter. Moreover, silencing of MYC or its cofactor MAX with siRNA increased JAK2 expression and IFNγ responsiveness of melanomas, while concomitantly enhancing the effector functions of T cells coincubated with MYC-overexpressing cells. Thus, we propose that MYC plays a pivotal role in immunotherapy resistance through downregulation of JAK2.
Databáze: OpenAIRE