[Antitumor activity and structure-activity relationship of seven lanostane-type triterpenes from Fomitopsis pinicola and F. officinalis].

Seven lanostane-type triterpenes including fomitopsin C(1),3-keto-dehydrosulfurenic acid(2),dehydroeburiconic acid(3),3-acetyloxylanosta-8, 24-dien-21-oic acid(4),pinicolic acid A(5),trametenolic acid B(6),and eburicoic acid(7),were isolated from the fruitbodies of Fomitopsis pinicola and F. officinalis. In vitro assay, all compounds were evaluated against MCF-7, HeLa, HepG2 and A549 cells lines using the MTT assay and the structure-activity relationship of antitumor activity was discussed. The results showed that the seven compounds were more sensitive to MCF-7 cells.The IC₅₀ value for MCF-7 was 2<5<4<1<3<6<7. H22 tumor mouse model was used to assay compounds 2, 3, 4 and 5 in vivo. Compounds 2 and 4 had obvious effect and the necrosis area and measurement were positively correlated. The results showed that compounds 2, 4 and 5 had significant antitumor activities at a dose of 20 mg•L⁻¹ with 65.31%, 56.71%, 58.72% suppression, respectively, approaching to CTX group with 69.19% suppression in subcutaneous H22-implanted mice.The results showed that these compounds had significant against the expression of VEGF, cytokines IL-4 and IFN-γ tumor, additionally, the structure-activity relationship of lanostane-type triterpenes indicated that the acetoxyl or carbonyl at C-3 and hydroxy at C-15 can enhance the antitumor activity.