In Silico Screening Studies on Methanesulfonamide Derivatives as Dual Hsp27 and Tubulin Inhibitors Using QSAR and Molecular Docking

The expression of heat shock protein 27 (Hsp27) as a chaperone protein, is increased in response to various stress stimuli such as anticancer chemotherapy. This phenomenon can lead to survive of the cells and causes drug resistance. In this study, a series of methanesulfonamide derivatives as dual Hsp27 and tubulin inhibitors in the treatment of cancer were applied to quantitative structure–activity relationship (QSAR) analysis. A collection of chemometrics methods such as MLR, FA-MLR, PCR, and GA-PLS was applied to make relations between structural characteristics and anti-proliferative activity of them against SKBR-3 breast cancer cell line. The best multiple linear regression equation was obtained from GA-PLS. Concerning this model, new potent lead compounds were designed based on new structural patterns using in silico-screening study. To obtain their binding mode, binding site and types of their interactions to both tubulin and HSP27, molecular docking studies were also conducted on these compounds. The validity of docking protocol was also explored. The results obtained from this docking study indicate that the important amino acids inside the active site cavity that are in charge of essential interactions with HSP27 are Arg140, Thr139, Phe138, Cys137, Arg136, Phe104, His103, Val101, and Asp100. And this important amino acids in essential interactions with tubulin are Asn258, Val238, Cys241, Asn350, Leu255, Met259, Val315, Thr353, Arg221, Thr179 and Ser178.