Cytotoxicity of thirteen South African macrofungal species against five cancer cell lines

- 13 South African macrofungal spp. were screened for cytotoxicity against 5 cancer cell lines and apoptosis determined.
- F. fomitopsis, G. junonius and P. sanguineus showed cytotoxicity against five human cancer cell lines.
- P. sanguineus has an IC50 < 10 μg/mL against MIA PaCa-2.
- Morphological characteristics are associated with apoptotic cell death.

Fungi are an important source of traditional medicine in Asian and Western countries. Globally, cancer is one of the leading causes of death with 22 million cases predicted by 2030. The cytotoxicity of 13 South African macrofungal species against HeLa, HT-29, MCF-7, MIA PaCa-2 and PC-3 cancer cell lines was measured using the 3-(4,5-dimethyl-2-thiazolul)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, and the IC50 values determined for the most cytotoxic macrofungal species. Fomitopsis lilacinogilva had IC50 values of 42.2, 55.1, 63, 48.8 and 79.8 μg/mL against the HeLa, HT-29, MCF-7, MIA PaCa-2 and PC-3 cancer cell lines, respectively. Gymnopilus junonius had IC50 values of 55.1 and 52.5 μg/mL against the HeLa and MIA PaCa-2 cancer cell lines, respectively. Pycnoporus sanguineus had IC50 values of 24.2, 48.1, 32.7, < 10 and 28.6 μg/mL against the HeLa, HT-29, MCF-7, MIA PaCa-2 and PC-3 cancer cell lines, respectively. Apoptosis of HeLa cancer cells induced by F. lilacinogilva, G. junonius and P. sanguineus was confirmed using Hoechst and phalloidin staining. Morphological changes included condensed chromatin, membrane blebbing, loss of cytoskeletal arrangement and rounding up of cells, as well as multi- and micronuclei. Macrofungal research in South Africa remains a novel field, and this study provides interesting data on the cytotoxicity of South African macrofungal species against some of the most common cancers affecting humans worldwide.