Loading
Loss of one copy of the RB1 gene was found in 72% of basal-like breast cancers, with low RB1 messenger RNA and high p16, and an RB1-loss expression signature predicted outcome and possibly chemotherapy response.
88 primary breast carcinomas and matched normal DNA were subtyped by expression and assessed for RB1 loss of heterozygosity with polymorphic markers. LOH was seen in 39% overall, 72% of basal-like and 62% of luminal B tumours, which also showed low RB1 mRNA; p16INK4a was highly expressed in basal-like tumours consistent with RB1 loss. An RB1-LOH signature was highly prognostic and a potential predictor of neoadjuvant chemotherapy response.
Functional RB1 loss is part of basal-like biology, which explains why CDK4/6 inhibitors have not worked in TNBC and why the cell-cycle vulnerability there lies downstream of RB.
Shares Charles M. Perou, RB1, p53 / RB / cell-cycle checkpoint, Breast cancer (all types).
Shares CDK4/6, p53 / RB / cell-cycle checkpoint, Triple-negative breast cancer (TNBC).
Shares CDK4/6, p53 / RB / cell-cycle checkpoint.
Shares Charles M. Perou, Triple-negative breast cancer (TNBC).
Shares Charles M. Perou, Triple-negative breast cancer (TNBC).
Shares CDK4/6, p53 / RB / cell-cycle checkpoint.