Anticancer Activity and Molecular Mechanisms of an Ursodeoxycholic Acid Methyl Ester-Dihydroartemisinin Hybrid via a Triazole Linkage in Hepatocellular Carcinoma Cells

Abstract

Hepatocellular carcinoma is the third most common cause of cancer-related death according to the International Agency for Research on Cancer. Dihydroartemisinin (DHA), an antimalarial drug, has been reported to exhibit anticancer activity but with a short half-life. We synthesized a series of bile acid–dihydroartemisinin hybrids to improve its stability and anticancer activity and demonstrated that an ursodeoxycholic–DHA (UDC-DHA) hybrid was 10-fold more potent than DHA against HepG2 hepatocellular carcinoma cells. The objectives of this study were to evaluate the anticancer activity and investigate the molecular mechanisms of UDCMe-Z-DHA, a hybrid of ursodeoxycholic acid methyl ester and DHA via a triazole linkage. We found that UDCMe-Z-DHA was even more potent than UDC-DHA in HepG2 cells with IC50 of 1 μM. Time course experiments and stability in medium determined by cell viability assay as well as HPLC-MS/MS analysis revealed that UDCMe-Z-DHA was more stable than DHA, which in part accounted for the increased anticancer activity. Mechanistic studies revealed that UDCMe-Z-DHA caused G0/G1 arrest and induced reactive oxygen species (ROS), mitochondrial membrane potential loss and autophagy, which may in turn lead to apoptosis. Compared to DHA, UDCMe-Z-DHA displayed much lower cytotoxicity toward normal cells. Thus, UDCMe-Z-DHA may be a potential drug candidate for hepatocellular carcinoma.

Dihydroartemisinin inhibits liver cancer cell migration and invasion by reducing ATP synthase production through CaMKK2/NCLX

“…DHA can also inhibit the activity of NADPH oxidase, thereby reducing the production of ROS (48). In addition, DHA can induce cell cycle arrest of liver cancer cells at the G 0 /G 1 phase, ROS generation and mitochondrial membrane potential loss, thereby leading to apoptosis (49). The present study demonstrated that CaMKK2-OE can significantly upregulate ATP formation and promote ROS generation in liver cancer cells, whereas knocking down NCLX expression could block these regulatory effects of CaMKK2.…”

Dihydroartemisinin-Ursodeoxycholic Bile Acid Hybrids in the Fight against SARS-CoV-2

“…Stability of DHA and DHA-UDCA-based hybrids in cell culture medium assessed by HPLC-MS analyses. Stability of DHA and hybrid DHA-UDC was reported in ref ; stability of hybrid DHA-t-UDCMe was reported in ref ; stability of DHA-s-UDCMe was recorded at 3, 6, 15, and 24 h. The data are presented as the mean ± SD of three independent experiments.…”

“…This compound, although not necessarily a structural analogue of DHA-t-UDCMe, has a labile ester linker between the two conjugation partners instead of the stable triazole moiety and could help elucidate the influence of the linker stability on the antiviral activity of the hybrid. The synthesis of DHA-s-UDCMe was straightforward: having obtained artesunate (ART) by following literature procedures, 45 33,34 were found stable up to 24 h of incubation in cell culture medium, whereas the parent DHA was found far more unstable, being decomposed up to 70% after 6 h (Figure 2). 33 The overall data indicated that the molecular hybridization actually improved the chemical stability with respect to the parent DHA although to a lesser extent in the case of hybrid DHA-s-UDCMe, which underwent decomposition up to 80% after 24 h.…”

“…Analogously, the DHA-s-UDCMe hybrid presents a residue of DHA covalently linked to the 3α-OH of UDCMe; however, in this case, a cleavable succinyl linker has been chosen. Both hybrids DHA-UDC and DHA-t-UDCMe were found stable up to 24 h of incubation in cell culture medium independently on the nature of the linkage/linker and the conjugation point, 33,34 whereas hybrid DHA-s-UDCMe showed a half-life time of around 15 h of incubation. All hybrids considered were found markedly more stable than unconjugated DHA that underwent decomposition up to 70% after 6 h of incubation time (Figure 2).…”

“…Three DHA-UDCA hybrids depicted in Figure c, presenting different linkages or conjugation points, were selected. Among them, DHA-s-UDCMe was newly synthesized, whereas DHA-UDC and DHA-t-UDCMe have previously been explored for anticancer activity in selected cancer cell lines by our group. − …”