RB1 and osteosarcoma: Significantly, the increased dose sensitivity to olaparib extended to a broad osteosarcoma-focussed cell panel (Fig. 1a), yielding a highly significant differential median sensitivity assessed using AUC values (Fig. 1b) in lines with known RB1-mutant status and/or lacking detectable RB1 expression (Fig. 1l), compared to RB1-normal lines.