Fig. 1: In vivo RNAi screens expose retinoblastoma vulnerabilities.

a Strategy to identify novel therapeutic targets in RB. Examples of disrupted hub/partners identified by DyNeMo are shown. b Sources of the 647 shRNAs targeting 147 genes for the primary in vivo dropout screen. c Design of the in vivo shRNA screens. d Primary screen data from orthotopic RB xenografts. shRNA enrichment/depletion was determined from Z-scores (full dataset in Table S1). Shaded area represents significant dropouts (Z < −1.96, p < 0.05 two tails). e Secondary screen data. In total, 138 shRNAs selected from the primary screen were tested in the indicated four orthotopic RB xenografts. The averaged log ratio tumor/T0 reads (n = 6) was plotted. Shaded area represents dropouts (full dataset in Table S1). The recurrent hits BRCA1, RAD51, and SKP2 are highlighted. f Summary of hits from the primary and secondary in vivo dropout screens. Hi: high rank; Med: medium rank; W: WERI-RB1; Y: Y79; red: high rank; dark green: medium rank; light green: low rank. g Westerns showing expression of the main hits BRCA1, RAD51, PABPC1, SKP2 in multiple RB lines. h Screen validation. Y79 cells were transduced with individual shRNAs of the indicated hits or a nonscoring control, knockdown efficiency assessed by western blot, and the effect on growth measured over 5 days by CellTiter-Glo reagent. Data were normalized to d0 and plotted (n = 3, mean ± SD, ***p < 0.001 two-way ANOVA, Sidak’s multiple comparisons test).