Abstract
DSCAM-AS1 is one of the few intensively studied lncRNAs with high specific expression in luminal breast cancer. It is directly regulated by estrogen receptor α (ERα) and plays vital roles in tumor proliferation, invasion, and tamoxifen resistance. However, the detailed function of DSCAM-AS1 in tumor progression and its clinical significance remain unclear. We reveal that DSCAM-AS1 regulates cell proliferation and colony formation by inducing the G1/S transition. RNA-seq analysis demonstrated that DSCAM-AS1 participates in crucial biological processes, including DNA replication, the G1/S phase transition, sister chromatid cohesion, chromosome segregation, protein localization to the chromosome and DNA recombination. Most importantly, in the retrospectively registered clinical analysis, high expression of DSCAM-AS1 is a poor prognostic factor in patients with luminal breast cancer treated with endocrine therapy. In conclusion, DSCAM-AS1 is a promising clinical therapeutic target that may prolong survival of luminal breast cancer patients treated with endocrine therapy.