Anticancer activity of 3-demethylubiquinone Q2. In vivo experiments and probable mechanism of action

Background: 3-Demethylubiquinone Q2 (3DMUbQ2), isolated from the ascidian Aplidium glabrum and later synthesized, is known as a natural product inhibiting EGF-induced malignant JB6 P₊ Cl 41 cell transformation. However, its in vivo anticancer properties and probable mechanism of this action have not been studied. Materials and Methods: Preventive and curable effects of 3DMUbQ2 on mice with inoculated Ehrlich carcinoma tumors were examined by magnetic resonance tomography. Capability to inhibit human tumor cell colony growth and induce their apoptosis was investigated using the anchorage-independent phenotype expression assay in soft agar and flow cytometry. Results: 3DMUbQ2 inhibits the growth of the solid Ehrlich carcinoma in mice, especially using the prophylactic scheme of administration (50% inhibition). It inhibits the phenotype expression of HT-460, HCT-116 and SK-MEL-28 human tumor cells and induces apoptosis of these cell lines, as well as that of HL-60 and THP-1 tumor cells. Conclusion: 3DMUbQ2 and other related marine polyprenylquinones have potential for development of a new antitumor agent in cancer prophylactics and treatment and should be further investigated.