ABSTRACT
OBJECTIVE The eradication of cancer stem cells(CSCs)is signifcant for cancer therapy and prevention.METHODS In this study,we evaluated WM130,a novel derivative of matrine,for its effect on CSCs using human hepatocellular carcinoma(HCC)cell lines,their sphere cells,and sorted EpCAM+cells. RESULTS We revealed that WM130 could not only inhibit proliferation and colony formation of HCC cells, but also suppress the expression of some stemness-related genes and up-regulate some mature hepatocyte marker genes, indicating a promotion of differentiation from CSCs to hepatocytes. WM130 also suppressed the proliferation of doxorubicin-resistant hepatoma cells, and markedly reduced the cells with CSC biomarker EpCAM.Moreover,WM130 suppressed HCC spheres,not only primary spheres but also subsequent spheres,indicating an inhibitory effect on self-renewal capability of CSCs.Interestingly,WM130 exhibiteda remarkable inhibitory preference on HCC spheres and EpCAM+cells rather than their parental HCC cells and EpCAM- cells respectively. In vivo, WM130 inhibited HCC xenograft growth, decreased the number of sphere-forming cells, and remarkably decreased the levels of EpCAM mRNA and protein in tumor xenografts. Better inhibitory effect was achieved by WM130 in combination with doxorubicin.Further mechanism study revealed that WM130 inhibited AKT/GSK3β/β-catenin signaling pathway. CONCLUSION Collectively, our results suggest that WM130 remark-ably inhibits hepatic CSCs, and this effect may via the down-regulation of the AKT/GSK3β/β-catenin pathway.These findings provide a strong rationale for the use of WM130 as a novel drug candidate in HCC therapy.
ABSTRACT
A general strategy for the total synthesis of the antitumor agent apoptolidin (1) is proposed, and the chemical synthesis of the defined key building blocks (4, 5, 6, 8, and 9) in their enantiomerically pure forms is described. The projected total synthesis calls for a dithiane coupling reaction to construct the C(20)-C(21) bond, a Stille coupling reaction to form the C(11)-C(12) bond, and a Yamaguchi macrolactonization to assemble the macrolide ring, as well as two glycosidation reactions to fuse the carbohydrate units onto the molecule. First and second generation syntheses to the required fragments for apoptolidin (1) are described.
Subject(s)
Macrolides/chemical synthesis , StereoisomerismABSTRACT
No less than 30 stereogenic elements, a highly unsaturated 20-membered macrocyclic system, four carbohydrate units, and unique biological activity, make the natural occurring apoptolidin (1) a challenging synthetic target. The retrosynthetic analysis revealed five key building blocks-three for the construction of the macrolide ring B and two prospective pendant saccharide units-which were synthesized in a highly convergent manner and then connected. Apoptolidin's rather labile nature proved particularly challenging in the final deprotection, purification, and characterization procedures.
