Researchers identified a unique sugar molecule from the sea cucumber Holothuria floridana that potently inhibits sulfatase-2 (Sulf-2), an enzyme facilitating cancer cell invasion. Structural biology techniques elucidated the molecular motif responsible for this inhibition, potentially informing the synthesis of small molecule Sulf-2 inhibitors. Natural glycosaminoglycan analogs like these offer promising leads in anti-cancer drug development, addressing challenges in synthetic accessibility and therapeutic delivery.