Anticancer Activity and Induction of Multinucleation in Hematologic Cell Lines Mediated by Ganoderma Lucidum.

Over many centuries, herbal remedies have treated a variety of ailments. This empiric observational approach has produced a number of leads for formulated medicines. We have examined five phytochemical herbs with purported anti-cancer activities: Ganoderma lucidum, Isatis indigotica, Dendranthema morifolium, Rabdosia rubescens and Panax pseudoginseng. Ethanol and DMSO extracts were made of each herb, and these were screened for their antiproliferative activities (MTT-assay; doses: 50 μg/ml and 100 μg/ml) using a panel of 26 human cancer cell lines (16 hematologic cell lines). Ganoderma lucidum was the most effective agent, particularly against the 16 hematological cell lines. Further dose- and time-response MTT assays of Ganoderma were performed using the 7 most sensitive hematological cell lines: their ED₅₀’s were 26 μg/ml, HL-60; 63 μg/ml, U937; 50 μg/ml, K562 (all three are myeloid leukemias); 38 μg/ml, Blin-1; 30 μg/ml, Nalm-6 (both are B-ALLs); 40 μg/ml, RPMI8226 (multiple myeloma); 20 μg/ml, Daudi (Burkitt’s lymphoma). Cell cycle analysis revealed a G2/M arrest, most prominently in HL-60 cells (24% in G2/M compared to 12% in control cells cultured with 100 mg/ml Ganoderma for 3 days). Three hematological cell lines (HL-60, U937, Blin-1) were examined for apoptosis, which ranged between 10% – 35% and 30% – 49% compared to <6% in control cells after exposure to 100 and 200 mg/ml Ganoderma for 3 days, respectively (Annexin V staining). Of particular note, cytospin preparations of HL-60 cells revealed that Ganoderma lucidum caused prominent multinucleation. Dose-dependent studies revealed 1% multinucleation in the cells treated with 1 mg/ml, 5% with 10 mg/ml, 10% with 50 mg/ml, 40% with 75 mg/ml and 80% with 100 mg/ml Ganoderma at day 4 of culture. FACS analysis of PI stained HL-60 cells confirmed the increased DNA content of these cells. Of interest, multinucleation did not occur in 6 other hematologic and 6 solid tumor cell lines. In summary, we discovered that 5 phytochemical herbs have growth inhibitory effects on AML, CML, B-ALL, Burkitt’s lymphoma and multiple myeloma cell lines. The most effective drug was Ganoderma lucidum, and it induced cell death by apoptosis. Moreover, multinucleation was observed in HL-60 cells, which may provide interesting insight in the same process in normal cells, like megakaryocytes. Notably, these studies have identified one plant, Ganoderma lucidum, that deserves careful separation techniques to identify its anticancer molecule (s).