Finally, we demonstrate that c-Myc is required for S100A9-induced upregulation of PD-1/PD-L1, and that treatment of MDS HSPCs with anti-PD-1 antibody suppresses the expression of Myc target genes and increases the expression of hematopoietic pathway genes.
Little is known about MYC dysregulation in myeloid malignancies, and the authors were unable to find published studies that evaluated MYC protein expression in primary cases of myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML).
Overexpression of GYS1, MIF, and MYC is associated with adverse outcome and poor response to azacitidine in myelodysplastic syndromes and acute myeloid leukemia.
Vorinostat increased expression of genes down-regulated in MDS and/or AML (cFOS, COX2, IER3, p15, RAI3) and suppressed expression of genes over-expressed in these malignancies (AXL, c-MYC, Cyclin D1) and modulated cell cycle and apoptosis genes in a manner which would favor cell cycle arrest, differentiation, and apoptosis of neoplastic cells, consistent with the functional assays.
These results exclude MYC as the target gene and indicate that overexpression of C8FW may be the functionally important consequence of 8q24 amplicons in AML and MDS.
We have analyzed the methylation status of CCGG sites in and around the human proto-oncogene c-myc in blood cells from patients with acute and chronic leukemias and with myelodysplastic syndromes using restriction endonucleases.