Cell death induction by mycelium extracts from Pleurotus spp. on cervical cancer cell lines

Mushrooms have health benefits, including anti-tumoral properties. We evaluated the cytotoxic and cell death induction effects of water-soluble extracts of Pleurotus ostreatus and Pleurotus eryngii mycelium in the cervical cancer cell lines HeLa (HVP18⁺) and SiHa (HVP16⁺) as well as the non-tumoral cell line HaCaT. Both Pleurotus extracts presented similar protein patterns from 190 to 10 kDa and displayed protease activity on a gelatine substrate. The mycelium extracts of both Pleurotus strains induced a dose-dependent cytotoxic effect on HPV⁺ cells IC₅₀ 65 µg), whereas HaCaT cells were less susceptible (IC₅₀ 90 µg). The cytotoxic effect at the IC₅₀ concentration was not associated with apoptosis, the activation of Caspases-3/7 was not significantive; only P. eryngii induced a moderate (1.2-fold) increase in SiHa cells. Pleurotus extracts induced autophagy, mainly in SiHa cells (4.3-fold). Neither extracts induced changes in p53 protein expression, suggesting that the cytotoxic effect could be due to p53-independent pathways.