The aim of this research was to examine these novel xanthones and discover one particular common descriptor getting cytotoxic passion to assist the development of more active anticancer representatives. We as well as investigated the essential possible elements regarding action out-of xanthone facing cancer on such basis as common beliefs out-of cancer compliment of when you look at the silico molecular docking.
Colorectal cancer WiDR tissue and you will normal Vero structure was basically obtained from the new Lab out of Parasitology, Professors from Treatments, Gadjah Mada School
The synthesized xanthone compounds were the property of Yuanita (Laboratory of Organic Chemistry of the Faculty of Mathematics and Natural Sciences, Gadjah Mada University) and are listed in Table 1. Cells were cultured in RPMI 1640 (for WiDR) and M199 (for Vero) (Sigma-Aldrich Co., St Louis, MO, USA) supplemented with 0.1 mg/mL streptomycin (Thermo Fisher Scientific, Waltham, MA, USA) and maintained in an incubator with 5% CO2 at 37°C. Only confluent cells were used for the experiment. This study received ethics approval from the Medical and Health Research Committee Faculty of Medicine, Gadjah Mada University, and Dr Sardjito General Hospital, number KE/FK/399/EC/2016.
The data set for the QSAR analysis was obtained from the cytotoxic activity test results. 50) values that were converted to log 1/IC50 and used as dependent variables in the QSAR analysis.
A personal computer with an Intel ® Pentium ® 2117U 1.80 Ghz Central processing unit, 4.00 GB RAM, five hundred GB harddisk, and you may a windows 8 ® os’s was utilized. All the quantum mechanical calculations regarding xanthones had been carried out that with Hyperchem 8 ® , and you can QSAR studies is actually performed by using the BuildQSAR system. 21 Preparation of receptor necessary protein and you may docking validation approach is did by using YASARA ( and you may planning of one’s ligand are did utilising the Chemdraw Ultra a dozen.0.2 and you will s. The fresh new molecular docking procedure are performed with the Flowers/Protein–Ligand Ant Program. 22 Meanwhile, the brand new Pymol system (pymol.org) was used to see brand new hydrogen ties in amino acid residues involving the ligand and you may receptors. 23
The in vitro cytotoxic activities were evaluated by using the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) method as described earlier 24 with modifications. Cells were seeded at 1?10 4 cells/well in 96-well plates and incubated for 24 h. They were then treated with 100 ?L of medium (as untreated control) or 100 ?L of varying concentrations of individual compounds (500, 250, 125, 62.5, , , 7.813, and 3.906 ?g/mL for the WiDR cell line, and 1,000, 500, 250, 125, 62.5, , , and 7.813 ?g/mL for the Vero cell line), 100 ?L of various concentrations of doxorubicin as a positive control (100, 50, 25, 12.5, 6.25, and 3.125 ?g/mL), and 100 ?L of medium without cells as a medium control. The plates were incubated at 5% CO2 and 37°C for 24 h. After treatment, the medium was removed, MTT solution (10 ?L per 100 ?L medium) was added to all wells, and plates were incubated at 5% CO2 37°C for 4 h 
. To the cells was then added 100 ?L of 10% sodium dodecyl sulfate in HCl 0.01 N; the cells were then incubated overnight to ensure that all formazan crystals were dissolved. The plates were read on a microplate enzyme-linked immunosorbent assay reader at 595 nm. The percentage of viable cells was determined according to the following formula:
Cytotoxic activity was represented as the inhibitory concentration 50% (IC50) of each compound that was determined by probit analysis of the sample concentration versus cell viability. The selectivity index (SI) was calculated from the ratio of IC50 in Vero versus that in WiDR cells. SI values >3 were considered as having high selectivity. 25