A Comprehension into Target Binding and Spatial Fingerprints of Noscapinoid Analogues as Inhibitors of Tubulin

Background: Owing to its potential to interfere in microtubule dynamics in the mitotic phase of cell cycle and selectively induce apoptosis in cancer cells without affecting normal cells, noscapine and its synthetic analogues have been investigated by other research groups in different cell lines for their capability to be used as anti-cancer agents. Objective: The present study is focused on the investigation of the mode of binding of noscapinoids with tubulin, prediction of target binding affinities and mapping of their spatial fingerprints (shape and electrostatic). Methods: Molecular docking assisted alignment based 3D-QSAR was used on a dataset (43 molecules) having an inhibitory activity (IC50 = 1.2-250 μM) against human lymphoblast (CEM) cell line. Results and Conclusion: Key amino acid residues of target tubulin were mapped for the binding of most potent noscapine analogue (Compound 11) and were compared with noscapine. Spatial fingerprints of noscapinoids for favorable tubulin inhibitory activity were generated and are proposed herewith for further pharmacophoric amendments of noscapine analogues to design and develop novel potent noscapine based anti-cancer agents that may enter into drug development pipeline.