Cannabigerol and Cannabichromene Induce Lung Cancer Cell Death and Apoptosis—Contribution of PPARα to Cannabigerol Effects

Cannabinoids are potential anticancer agents for the add-on treatment of malignant tumors. Here, the effects of the previously less-explored non-psychoactive phytocannabinoids cannabigerol (CBG) and cannabichromene (CBC) on survival, apoptosis, and mitochondrial function were assessed in A549 and H460 lung cancer cells. CBG and CBC triggered concentration-dependent cell death, autophagy, and mitochondrial apoptosis in both cell lines, with apoptosis indicated by Annexin V staining, activation of caspase-8, -9, and -3/7, loss of mitochondrial membrane potential, and elevated cytosolic levels of mitochondrial cytochrome c. CBG also upregulated ATF4, a stress-responsive transcription factor involved in autophagy and apoptotic signaling, and enhanced PARP cleavage. Both cannabinoids increased mitochondrial superoxide formation and reduced the mitochondrial oxygen consumption rate, with CBG additionally decreasing NDUFB8, a subunit of respiratory chain complex I. Pharmacological receptor modulation showed that CBG- and CBC-induced cell death occurred independently of CB1, CB2, TRPV1, TRPM8, and PPARγ, whereas CBG-mediated cell death relied on PPARα, which also contributed to its apoptotic effects. In summary, CBG and CBC induce apoptosis and cell death in A549 and H460 cells, with PPARα mediating the effects of CBG, highlighting its potential as a therapeutic target.