Insights into the cytotoxicity of Ganoderma adspersum mycelium extracts against human renal cancer cell lines

Ganoderma adspersum is a medicinal fungus known for its bioactive properties, including antibacterial, anticholinesterase, and antioxidant activities. While preliminary research suggests antiproliferative effects on breast cancer cells, its efficacy against other cancer types remains underexplored. This study aims to evaluate the antiproliferative activity of ethanolic extracts of Ganoderma adspersum on human renal cancer cells. Ethanolic extracts were prepared from (i) the liquid culture medium post-fermentation and (ii) the fungal mycelium. Both extracts were tested in vitro on human renal cancer cell lines Caki-1, 786-O and RCC-Shaw, as well as on non-tumor human renal HK-2 cells. Notably, we found that only the mycelium-derived ethanolic extract showed significant antiproliferative activity, reducing cell viability by more than 80% in both 786-O and RCC-Shaw cells after 72 hours. Concentrations of Gad mycelium extract up to 500 μg/ml were well tolerated by HK-2 non-tumor renal cells. Nuclear Magnetic Resonance (NMR) spectroscopy revealed marked differences in the composition of the two extracts. Based on the information on the most abundant metabolites in the Gad mycelium extract, specific compounds were tested in vitro to explore their effects on the cell viability. Our findings support the potential of Ganoderma adspersum mycelium extract as a selective, non-toxic source of bioactive compounds with antiproliferative properties within the range of 125 – 500 μg/ml.