Molecular and cellular composition changes after neoadjuvant letrozole and palbociclib in early luminal breast cancer.

ABSTRACT: The NeoPAL trial compares neoadjuvant letrozole-palbociclib (LP) with chemotherapy (CT) in 103 patients with high-risk, early luminal breast cancer. At surgery, the NanoString BC360 proliferation score and Ki67 expression are reduced in both arms, together with upregulation of immune-related signatures. Overall, there is very little difference in the changes observed with LP as compared to CT, even in signatures related to response to estrogen and CDK4/6 manipulation. Deconvolution of bulk RNA sequencing (RNA-seq) data reveals high content at baseline in cancer cells, immunosuppressive cancer-associated fibroblasts, FOXP3+ CD4⁺ regulatory T lymphocytes, and TREM2+ macrophages. In contrast, myoepithelial cells, normal-like fibroblasts, FOLR2+ macrophages, and SELL+ CD4⁺

SUBMITTER: Cottu P 

PROVIDER: S-EPMC12866096 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature