Synthesis and Biological Evaluation of Novel Heterocyclic Imines Linked Coumarin- Thiazole Hybrids as Anticancer Agents.

Abstract

BACKGROUND:

Human Galectin-1, a protein of lectin family showing affinity towards β-galactosides has emerged as a critical regulator of tumor progression and metastasis, by modulating diverse biological events including homotypic cell aggregation, migration, apoptosis, angiogenesis and immune escape. Therefore, galectin-1 inhibitors might represent novel therapeutic agents for cancer.

METHODS:

A new series of heterocyclic imines linked coumarin-thiazole hybrids (6a-6r) was synthesized and evaluated for its cytotoxic potential against a panel of six human cancer cell lines namely, lung (A549), prostate (DU-145), breast (MCF-7 & MDA-MB-231), colon (HCT-15 & HT-29) using MTT assay. Characteristic apoptotic assays like DAPI staining, cell cycle, annexin V and Mitochondrial membrane potential studies were performed for the most active compound. Furthermore, Gal-1 inhibition was confirmed by ELISA and fluorescence spectroscopy.

RESULTS:

Among all, compound 6g {3-(2-(2-(pyridin-2-ylmethylene) hydrazineyl) thiazol-4-yl)-2H-chromen-2- one} exhibited promising growth inhibition against HCT-15 colorectal cancer cells with an IC50 value of 1.28 ± 0.14 µM. The characteristic apoptotic morphological features like chromatin condensation, membrane blebbing and apoptotic body formation were clearly observed with compound 6g on HCT-15 cells using DAPI staining studies. Further, annexin V-FITC/PI assay confirmed effective early apoptosis induction by treatment with compound 6g. Loss of mitochondrial membrane potential and enhanced ROS generation were confirmed with JC-1 and DCFDA staining method, respectively by treatment with compound 6g, suggesting a possible mechanism for inducing apoptosis. Moreover, flow cytometric analysis revealed that compound 6g blocked G0/G1 phase of the cell cycle in a dose-dependent manner. Compound 6g effectively reduced the levels of Gal-1 protein in a dose-dependent manner. The binding constant (Ka) of 6g with Gal-1 was calculated from the intercept value which was observed as 1.9 x 107 M-1 by Fluorescence spectroscopy. Molecular docking studies showed strong interactions of compound 6g with Gal-1 protein.

CONCLUSION:

Our studies demonstrate the anticancer potential and Gal-1 inhibition of heterocyclic imines linked coumarin-thiazole hybrids.

• Authors: Nerella S Goud, Mahammad S Ghouse, Jatoth Vishnu, Jakkula Pranay, Ravi Alvala, Venu Talla, Insaf A Qureshi, Mallika Alvala
• Journal: Anti-cancer agents in medicinal chemistry (Anticancer Agents Med Chem) Vol. 19 Issue 4 Pg. 557-566 ( 2019) ISSN: 1875-5992 [Electronic] Netherlands
• PMID: 30734685 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright© Bentham Science Publishers; For any queries, please email at [email protected].

Chemical References

• Antineoplastic Agents
• Coumarins
• Heterocyclic Compounds
• Imines
• Thiazoles
• coumarin

Topics

• Antineoplastic Agents (chemical synthesis, pharmacology)
• Cell Line, Tumor
• Coumarins (chemistry)
• Drug Screening Assays, Antitumor
• Heterocyclic Compounds (chemistry)
• Humans
• Imines (chemical synthesis, pharmacology)
• Membrane Potential, Mitochondrial (drug effects)
• Molecular Docking Simulation
• Thiazoles (chemistry)