A Cytotoxic Porphyrin from North Pacific Brittle Star Ophiura sarsii

Triple-negative breast cancer (TNBC) represents the deadliest form of gynecological tumors currently lacking targeted therapies. The ethanol extract of the North Pacific brittle star Ophiura sarsii presented promising anti-TNBC activities. After elimination of the inert material, the active extract was submitted to a bioguided isolation approach using high-resolution semipreparative HPLC-UV, resulting in one-step isolation of an unusual porphyrin derivative possessing strong cytotoxic activity. HRMS and 2D NMR resulted in the structure elucidation of the compound as (3S,4S)-14-Ethyl-9-(hydroxymethyl)-4,8,13,18-tetramethyl-20-oxo-3-phorbinepropanoic acid. Never identified before in Ophiuroidea, porphyrins have found broad applications as photosensitizers in the anticancer photodynamic therapy. The simple isolation of a cytotoxic porphyrin from an abundant brittle star species we describe here may pave the way for novel natural-based developments of targeted anti-cancer therapies.

Automated summary

The discovery of a novel cytotoxic porphyrin compound with potential anti-TNBC activity from the ethanol extract of the North Pacific brittle star Ophiura sarsii may lead to the development of targeted natural-based therapies for breast cancer. The compound, (3S,4S)-14-Ethyl-9-(hydroxymethyl)-4,8,13,18-tetramethyl-20-oxo-3-phorbinepropanoic acid, was isolated using a bioguided approach and possesses strong cytotoxic properties. Porphyrins have not been previously identified in Ophiuroidea and have wide applications in anticancer photodynamic therapy.