coibamide A

Coibamide A is a potent marine-derived cyclopeptide (specifically a depsipeptide) natural product originally isolated from a Panamanian cyanobacterium (*Leptolyngbya* sp.). It exhibits significant antiproliferative and cytotoxic activity against a variety of human cancer cell lines, with particular potency noted in glioblastoma models. The drug functions as a potent and selective inhibitor of the Sec61 translocon, the primary protein conducting channel in the endoplasmic reticulum (ER) membrane. By binding to the Sec61α subunit, coibamide A blocks the co-translational translocation of nascent polypeptides into the ER lumen, thereby preventing the biogenesis and secretion of a broad spectrum of proteins, including growth factors and receptors essential for tumor cell survival and intercellular signaling. Preclinical studies have demonstrated its ability to suppress the secretome of glioma cells and reduce tumor growth in glioblastoma xenograft models.