Fig. 5From: Whole-exon sequencing of human myeloma cell lines shows mutations related to myeloma patients at relapse with major hits in the DNA regulation and repair pathwaysThe sensitivity to palbociclib is associated with the lack of RB1 deletion/mutation in CCND1+ human myeloma cell lines. a Cells were cultured for 24 h with palbociclib (500 nM); cell cycle modifications (a) and Rb phosphorylation (b) were assessed by propidium iodide staining and Western blotting, respectively. For HMCLs harboring a functional RB1, mean phase S/G2 reduction was 26% (95% CI = 16–34%) (paired t test, p = 0.03) and mean (pRb/Rb reduction was 63% (95% CI = 42–91%) (paired t test, p = .03). c, d, e Cells were cultured for 4 days with increasing concentrations of palbociclib, and sensitivity was determined by the area under the curve (AUC) using the MTT assay. c Correlation between S/G2 phase inhibition and palbociclib sensitivity (AUC z-score), bootstrapped robust linear regression. d, e Palbociclib sensitivity according to either the CDKN2A/CDKNC status or MM molecular classification. RB1 abnormal HMCLs are indicated (Mann–Whitney test)Back to article page