Integrated In silico and In vitro Discovery of A New Anticancer Thiadiazole Analog Targeting VEGFR-2

In this work, a new thiadiazole analogue (TDA) was designed with the intention of incorporating key features of Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2) inhibitors, and then was examined computationally and experimentally. In vitro (cytotoxicity on MCF-7, HepG2 and WI-38 cell lines, in vitro VEGFR-2 assay, cell cycle analysis, apoptosis assays, RT-PCR, and migration studies), in addition to in silico (molecular docking, ADMET, MD simulations and DFT studies) were conducted. Prior to synthesis, docking and ADMET studies yielded predictions indicating favorable activity and drug likeness. After synthesis, the results demonstrated promising inhibitory activity of TDA on MCF-7 and HepG2 cancer cell lines. These results were notably close to those of sorafenib. The in vitro VEGFR-2 assay revealed significant inhibition, with an IC50 value of 0.283 µM. Selectivity studies indicated a favorable safety profile, with reduced toxicity towards normal lung cells (WI-38). Cell cycle analysis of TDA revealed a significant arrest in the G0-G1 phase, compared to the control group. Apoptosis assays demonstrated a considerable increase in programmed cell death, particularly in the early stages as opposed to the control group. Additionally, there was a notable increase in the expression of the pro-apoptotic gene Bax and a downregulation of the anti-apoptotic gene Bcl2 in MCF-7 cells treated with TDA. TDA also exhibited an anti-angiogenic potential through decreasing the abilities of the MCF-7 cells to migrate and heal. Computationally, various MD simulations studies indicated stable interactions between TDA and VEGFR-2 over 200 ns on both mechanical and energetic levels. DFT studies confirmed reactivity and stability of TDA. These comprehensive findings emphasize TDA’s potential as a multi-targeted candidate for further development in cancer therapy. The promising inhibitory activity, favorable safety profile, and mechanistic insights highlight TDA as a noteworthy contender through further in vivo studies and modifications.