PCNA and acute myeloblastic leukemia with maturation: The cell proliferation was also confirmed by PCNA expression in the 3-dimensionaly-cultured AM tumoroids (Additional file 1: Fig. S6A), The PCNA positive cell were dramatically increased in CACNA1C-overexpressed AM tumoroids and significantly decreased in the VPM treatment group (Additional file 1: Fig. S6B).