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Genomic analysis of Tet2 knockout macrophages

ABSTRACT: Ten-Eleven-Translocation-2 (Tet2) is a DNA methylcytosine dioxygenase that functions as a tumor suppressor in hematopoietic malignancies. In this study, we revealed a role for Tet2 in sustaining the immunosuppressive function of tumor-tissue myeloid cells. We found that Tet2 expression is increased in intratumoral myeloid cells both in mouse models of melanoma and in melanoma patients, and that this increased expression is dependent on an IL-1R-MyD88 pathway. Ablation of Tet2 in myeloid cells suppressed melanoma growth in vivo, and shifted the immunosuppressive gene expression program in tumor-associated macrophages to a proinflammatory one, with a concomitant reduction of the immunosuppressive function. This resulted in increased numbers of effector T cells in the tumor, and T cell depletion abolished the reduced tumor growth observed upon myeloid-specific deletion of Tet2. Our findings reveal a non-cell-intrinsic, tumor-promoting function for Tet2, and suggest that Tet2 may present a therapeutic target for the treatment of non-hematologic malignancies.

ORGANISM(S): Mus musculus

PROVIDER: GSE98964 | GEO | 2017/08/15

SECONDARY ACCESSION(S): PRJNA386935

REPOSITORIES: GEO

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B-cell tumor development in Tet2-deficient mice

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