NOP2 and acute myeloid leukemia: This experiment demonstrated very strong PR-RCA signals of co-localization of NSUN1 and RNA-pol-II CTD-S2P in the 5-AZA-resistant AML/MDS bone marrow cells and much weaker PL-RCA signals in the 5-AZA-sensitive AML/MDS bone marrow cells (Fig. 10a).