LYN-activating mutations mediate antiestrogen resistance in estrogen receptor-positive breast cancer.

ABSTRACT: Estrogen receptor-positive (ER(+)) breast cancers adapt to hormone deprivation and become resistant to antiestrogen therapy. Here, we performed deep sequencing on ER(+) tumors that remained highly proliferative after treatment with the aromatase inhibitor letrozole and identified a D189Y mutation in the inhibitory SH2 domain of the SRC family kinase (SFK) LYN. Evaluation of 463 breast tumors in The Cancer Genome Atlas revealed four LYN mutations, two of which affected the SH2 domain. In addition, LYN was upregulated in multiple ER(+) breast cancer lines resistant to long-term estrogen deprivation (LTED). An RNAi-based kinome screen revealed that LYN is required for growth of ER(+) LTED breast cancer cells. Kinase assays and immunoblot analyses of SRC substrates in transfected cells indicat

SUBMITTER: Schwarz LJ 

PROVIDER: S-EPMC4348968 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature