TET2 and myelodysplastic syndrome: Moreover, tumor-associated macrophages with absent TET2 expression exhibit an immune-active phenotype, including increased expression of inflammatory cytokines and decreased expression of ARG1, which promotes the anti-tumor T cell response (Pan et al., 2017), although another study showed that mutations of DNMT3A and TET2 are most likely associated with the increased expression of ARG1 in bone marrow myelomonocytic cells in MDS/CMML patients (Cull et al., 2018).