Phytochemistry and Cytotoxic Activity of Aquilaria crassna Pericarp on MDA-MB-468 Cell Lines.

The extracts of Aquilaria crassna pericarp were investigated on the MDA-MB-468, a breast cancer cell line, at desired concentration (1-50 µg/mL). The results showed that the dichloromethane (DCM) extract exhibited the strongest toxicity and was carried out subsequently. A total of nine compounds were isolated from the DCM extract using column chromatography and recrystallization, of which their structures were determined. Intriguingly, in addition to the previously reported compounds, neocucurbitacin A, a cucurbitacin triterpenoid aglycone with a lactone in ring A, was reported for the first time in the Aquilaria genus. Among the isolated compounds, cucurbitacin E highly inhibited MDA-MB-468 cell growth in a dose-dependent manner. Owing to binding abilities with the SH2 domain in the molecular docking study, cucurbitacin E, neocucurbitan A, neocucurbitan B, and cucurbitacin E 2-O-ß-d-glucopyranoside act as STAT3 inhibitors and are suitable for further research. This study suggests thatAquilaria crassnafruits could serve as a promising source of natural compounds with potential anticancer effects, particularly against breast cancer.

Design, synthesis, in vitro and in silico evaluation of anti-colorectal cancer activity of curcumin analogues containing 1,3-diphenyl-1H-pyrazole targeting EGFR tyrosine kinase.

Recent studies have shown that monocarbonyl analogues of curcumin (MACs) and 1H-pyrazole heterocycle both demonstrated promising anticancer activities, in which several compounds containing these scaffolds could target EGFR. In this research, 24 curcumin analogues containing 1H-pyrazole (a1-f4) were synthesized and characterized by using modern spectroscopic techniques. Firstly, synthetic MACs were screened for cytotoxicity against human cancer cell lines such as SW480, MDA-MB-231 and A549, from which the 10 most potential cytotoxic compounds were identified and selected. Subsequently, the selected MACs were further screened for their inhibition against tyrosine kinases, which showed that a4 demonstrated the most significant inhibitory effects on EGFRWT and EGFRL858R. Based on the results, a4 further demonstrated its ability to cause morphological changes, to increase the percentage of apoptotic cells, and to increase caspase-3 activity, suggesting its apoptosis-inducing activity on SW480 cells. In addition, the effect of a4 on the SW480 cell cycle revealed its ability to arrest SW480 cells at G2/M phase. In subsequent computer-based assessments, a4 was predicted to possess several promising physicochemical, pharmacokinetic, and toxicological properties. Via molecular docking and molecular dynamics simulation, a reversible binding mode between a4 and EGFRWT, EGFRL858R, or EGFRG719S, remained stable within the 100-ns simulation due to effective interactions especially the hydrogen bonding with M793. Finally, free binding energy calculations suggested that a4 could inhibit the activity of EGFRG719S more effectively than other EGFR forms. In conclusion, our work would provide the basis for the future design of promising synthetic compounds as anticancer agents targeting EGFR tyrosine kinase.

Synthesis, Biological Evaluation, and Molecular Modeling Studies of 1-Aryl-1H-pyrazole-Fused Curcumin Analogues as Anticancer Agents.

Addressing the growing burden of cancer and the shortcomings of chemotherapy in cancer treatment are the current research goals. Research to overcome the limitations of curcumin and to improve its anticancer activity via its heterocycle-fused monocarbonyl analogues (MACs) has immense potential. In this study, 32 asymmetric MACs fused with 1-aryl-1H-pyrazole (7a-10h) were synthesized and characterized to develop new curcumin analogues. Subsequently, via initial screening for cytotoxic activity, nine compounds exhibited potential growth inhibition against MDA-MB-231 (IC50 2.43-7.84 µM) and HepG2 (IC50 4.98-14.65 µM), in which seven compounds showing higher selectivities on two cancer cell lines than the noncancerous LLC-PK1 were selected for cell-free in vitro screening for effects on microtubule assembly activity. Among those, compounds 7d, 7h, and 10c showed effective inhibitions of microtubule assembly at 20.0 µM (40.76-52.03%), indicating that they could act as microtubule-destabilizing agents. From the screening results, three most potential compounds, 7d, 7h, and 10c, were selected for further evaluation of cellular effects on breast cancer MDA-MB-231 cells. The apoptosis-inducing study indicated that these three compounds could cause morphological changes at 1.0 µM and could enhance caspase-3 activity (1.33-1.57 times) at 10.0 µM in MDA-MB-231 cells, confirming their apoptosis-inducing activities. Additionally, in cell cycle analysis, compounds 7d and 7h at 2.5 µM and 10c at 5.0 µM also arrested MDA-MB-231 cells in the G2/M phase. Finally, the results from in silico studies revealed that the predicted absorption, distribution, metabolism, excretion, and the toxicity (ADMET) profile of the most potent MACs might have several advantages in addition to potential disadvantages, and compound 7h could bind into (ΔG -10.08 kcal·mol-1) and access wider space at the colchicine-binding site (CBS) than that of colchicine or nocodazole via molecular docking studies. In conclusion, our study serves as a basis for the design of promising synthetic compounds as anticancer agents in the future.

Molecular Docking Studies of Glycyrrhetinic Acid Derivatives as Anti- Colorectal Cancer Agents.

BACKGROUND: In this study, the anti-colorectal cancer (CRC) activities of 40 glycyrrhetinic acid derivatives were proposed and evaluated by the molecular docking method, which allowed the flexibility of both ligand-receptor, with twelve CRC-related targets. METHODS: The proposed derivatives, which clearly distinguish isomers at position 18 as well as the different tautomers, were divided into five groups, including (1) glycyrrhetinic acid and its oxidation derivatives, (2) glycoside derivatives, (3) 3ß-amine derivatives, (4) five-membered heterocyclic ring-combined derivatives, and (5) six-membered heterocyclic ring-combined derivatives. RESULTS: Finally, four out of twelve proposed targets related to CRC with good binding affinities to the proposed glycyrrhetinic acid derivatives were selected, including Epidermal Growth Factor Receptor (EGFR), Focal Adhesion Kinase (FAK), Lactate Dehydrogenase A (LDHA), and Thymidylate Synthase (TS). CONCLUSION: From there, 9/40 derivatives for EGFR (pKd ≥ 9); 10/40 derivatives for FAK (pKd ≥ 10); 9/40 derivatives for LDHA (pKd ≥ 10), and 6/40 derivatives for TS (pKd ≥ 9) were also obtained. The glycoside derivatives showed the best binding affinity (especially the glucuronide derivative 5b), followed by the 3ß-amino derivatives (especially the 3ß-(phenylamino) derivative 8b) and the five-membered heterocyclic ring-combined derivatives (especially the pyrrole derivative 10a or pyrazole derivative 11.2a), while the six-membered heterocyclic ring-combined derivatives had less potential to inhibit the 4 selected targets.

Synthesis of 1,5-diarylhaloimidazole analogs and their inhibitory activities against PGE2 production from LPS-treated RAW 264.7 cells.

A number of 1,5-diarylimidazole analogs were synthesized and evaluated their inhibitory activities of cyclooxygenase-2 catalyzed prostaglandin E(2) production. Reactions of 1,5-diarylimidazoles with halogenating reagents (NCS, NBS, NIS) afforded halogenated analogs. Among the analogs tested, compounds Ib, IIa, IIb and IIe exhibited significantly improved inhibitory activities against COX-2-mediated PGE(2) production from LPS-induced RAW 264.7 cells compared to those of the parent 1,5-diarylimidazoles. Especially, the analogs Ib (IC(50)=0.55 µM) and IIa (IC(50)=0.58 µM) showed best results. Halogenation on the 1,5-diarylimidazole ring enhanced inhibitory activities against COX-2 catalyzed PGE(2) production, however, inhibitory activities were significantly varied by position(s) and species of the substituted halogen(s).