NOP2 and myelodysplastic syndrome: The PL-RCA experiments with anti-NSUN1 and BRD4 antibodies performed in the same sets of clinical bone marrow specimens demonstrated a similar co-localization, with significantly increased PL-RCA signals in the 5-AZA-resistant MDS/AML specimens compared to those in the 5-AZA-sensitive AML/MDS bone marrow specimens (Fig. 10b).