Endogenous miR-16-1 inhibits CCND1 translation in H157. (A) Serum starvation increases miR-16-1 by approximately 800% in H157 and approximately 600% in Jeko-1. Serum starvation also increases CCND1 mRNA approximately 200% in H157 but decreases CCND1 mRNA in Jeko-1. (B) Serum starvation decreases CCND1 protein expression in H157 by approximately 30% at 48 hours and has no effect on CCND1 protein expression in Jeko-1 even at 96 hours. (C) Western blot analysis showing down-regulation of CCND1 protein expression in H157, while no changes occurred in Jeko-1 with serum starvation. (D) Cell-cycle analysis showing cell-cycle progression in H157 and Jeko-1 with serum starvation. The accumulation of cells in G1-phase in H157 at 48 hours indicates that serum starvation causes cell-cycle arrest. Notice that cell-cycle progression does not change dramatically in Jeko-1 even with serum starvation.