Molecular Therapy Oncology 2026: Fibulin-4-Targeting Peptide Selectively Killed Metastatic Breast Cancer Cells in Mouse Models
A Molecular Therapy Oncology 2026 paper from a multi-institution collaboration reported that a peptide engineered against Fibulin-4 — a glycoprotein overexpressed in metastatic breast cancer extracellular matrix — successfully targeted and killed metastatic breast cancer cells in mice. The same peptide doubles as an imaging probe, supporting peptide-based detection alongside therapy. The Fibulin-4 target is significant because metastatic breast cancer remains the leading cause of breast cancer mortality and current targeted therapies (HER2, hormone-receptor) leave a substantial therapy gap for triple-negative metastatic disease. The work joins the broader peptide-drug-conjugate field in which six PDCs are in Phase 3 trials and roughly 96 are in development, even as only Lutathera holds active FDA approval after the 2024 Pepaxto withdrawal.