Destruxin B is a cyclic peptide with insecticidal and anticancer activity isolated from the insect pathogenic fungus Metarhizium isopliae. Destruxin B induces apoptosis of human non-small cell lung cancer cells through the Bcl-2 family-dependent mitochondrial pathway. Destruxin B through caspase-mediated apoptosis can significantly activate caspase-3 in vitro and in vivo, reducing the proliferation of tumor cells.

Destruxin B (1-30 μM; mitochondrial blocking caspase cascade activation inhibits cell proliferation of Destruxin B (1-30 μM; 48 hours) H1299 cells and A549 cells with IC50 of 4.1 μM and 4.9 μM, respectively. Destruxin B (1.25-20.00μM; 48 hours) plays an important role in the induced apoptotic cell death of A549 cells. The treatment of 12 and 24 hours significantly increases the level of A549 cell promoter protein PUMA and reduces the resistance to degradation in an alternating manner of concentration and time The level of protein Mcl-1. Destruxin B (10 or 20 μm; 72 hours) treatment significantly reduced the survival ability of HT-29 human colorectal cancer with time and dose reduction.

Destruxin B (DB) (injection; 0.5-15 mg/kg/d for 6 weeks) reduces tumor growth in a time- and dose-dependent manner.