Synthesis and evaluation of selected 1,3,4-oxadiazole derivatives for in vitro cytotoxicity and in vivo anti-tumor activity

Abstract

The oxadiazole moiety is known for its anticancer activity through its antiangiogenic and mitostatic potential. Taking this as a cue, the present study was designed to investigate the anti-cancer potential of selected oxadiazole derivatives. Twelve 1,3,4-oxadiazole derivatives (AMK OX-1 to AMK OX-12) were synthesized and were tested for IC 50 values through brine shrimp lethality assay and MTT assay on HeLa and A549 cell lines. Four compounds, AMK OX-8, 9, 11 and 12 showed potential cytotoxicity activity with low IC 50 value. These compounds produced considerable cytotoxic effect on Hep-2 and A549 cancer cell lines. However, they were found to be comparatively safer to normal cell lines, viz., V-79 cell lines than to the tested cancer cell lines, such as HeLa, A 549, and Hep2 cell lines. The mechanism of cytotoxicity was evaluated through nuclear staining and DNA ladder assay. Although DNA ladder assay showed DNA fragmentation (apoptotic phenomenon) in Hep-2 cells treated with only AMK OX-12, the staining procedures using acridine orange, ethidium bromide and propidium iodide showed apoptotic bodies in cells treated with AMK OX-8, 9 and 12 also. In JCI staining on isolated mitochondria of Hep2 cells, AMK OX-8, 9-11 and 12 displayed increasing fluorescence intensity with time which confirmed involvement of mitochondrial pathway and intrinsic pathway of apoptosis. All four compounds were found to be safe in acute oral toxicity study in Swiss albino mice. These derivatives were effective in reducing tumor size and weight in the in vivo DLA-induced solid tumor model. They were found to be significantly effective in reducing tumor volume and tumor weight.

Biological Evidences of Hepatocellular Carcinoma Treatment with 1,3,4-oxadiazole-2-thiol as Anticancer Agent

“…Based on those investigations it was possible to select pharmacologically active structures without mutagenic liability [37]. In addition to, previously stated DNA fragmentation (apoptotic phenomenon) in Hep-2 cells treated with oxadiazole derivative, the staining procedures using ethidium bromide and propidium iodide showed apoptotic bodies in cells of oxadiazole derivative treatment [38].…”

Novel 1,3,4-oxadiazole Targets STAT3 Signaling to Induce Antitumor Effect in Lung Cancer

“…A limited number of studies have demonstrated the in vivo antitumor activity of oxadiazoles. Tiwari and colleagues reported that four 1,3,4-oxadiazoles decrease the tumor volume in Dalton’s lymphoma ascites-inoculated mice [ 57 ]. CHK9 displayed good antitumor activity in lung cancer model with depletion of activated STAT3 and other oncogenic proteins in tumor tissues.…”

Groundbreaking Anticancer Activity of Highly Diversified Oxadiazole Scaffolds

“…Tiwari et al synthesized a library of disubstituted 1,3,4-oxadiazoles, containing two phenyl rings with various substituents, and investigated their biological activity both in vitro and in vivo [ 100 ]. Among them, AMK OX-12 ( Figure 11 ) showed a significant toxic effect on Hep2 cells, with IC 50 of 0.0007 µM after 72 h of incubation and, at the same time, displayed low toxicity (IC 50 > 50 µM) on non-malignant cells (Chang Liver and V79).…”