Ali Zeiz
1 
, Ranin Kawtharani
2, Mirvat Elmasri
3, Ghada Khawaja
1, Eva Hamade
3,4, Aida Habib
5, Abeer J. Ayoub
4, Mohamed Abarbri
6, Mohammad H. El-Dakdouki
7* 1 Department of Biological Sciences, Faculty of Science, Beirut Arab University, Debbieh, Lebanon
2 Laboratory of Medicinal Chemistry and Natural Products, Lebanese University, Faculty of Science-I, Beirut, Lebanon
3 Department of Chemistry and Biochemistry, Faculty of Science-I, Lebanese University, Beirut, Lebanon
4 Laboratory of Cancer Biology and Molecular Immunology, Faculty of Sciences-I, Lebanese University, Beirut, Lebanon
5 Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha 2713, Qatar
6 Laboratoire de Physico-Chimie des Matériaux et des Electrolytes pour l'Energie (PCM2E)., EA 6299. Avenue Monge Faculté des Sciences, Parc de Grandmont, 37200 Tours, France
7 Department of Chemistry, Faculty of Science, Beirut Arab University, Debbieh, Lebanon
Abstract
Introduction: The anticancer and anti-inflammatory activities of a novel series of eleven pyrimido[1,2-b]pyridazin-2-one analogues substituted at position 7 were assessed in the current study.
Methods: The physicochemical characteristics were studied using MolSoft software. The antiproliferative activity was investigated by MTT cell viability assay, and cell cycle analysis elucidated the antiproliferative mechanism of action. Western blot analysis examined the expression levels of key pro-apoptotic (Bax, p53) and pro-survival (Bcl-2) proteins. The anti-inflammatory activity was assessed by measuring the production levels of nitric oxide in RAW264.7 cells, and the expression levels of COX-2 enzyme in LPS-activated THP-1 cells. In addition, the gene expression of various pro-inflammatory cytokines (IL-6, IL-8, IL-1β, TNF-α) and chemokines (CCL2, CXCL1, CXCL2, CXCL3) was assessed by RT-qPCR.
Results: Compound 1 bearing a chlorine substituent displayed the highest cytotoxic activity against HCT-116 and MCF-7 cancer cells where IC50 values of 49.35 ± 2.685 and 69.32 ± 3.186 µM, respectively, were achieved. Compound 1 increased the expression of pro-apoptotic proteins p53 and Bax while reducing the expression of pro-survival protein Bcl-2. Cell cycle analysis revealed that compound 1 arrested cell cycle at the G0/G1 phase. Anti-inflammatory assessments revealed that compound 1 displayed the strongest inhibitory activity on NO production with IC50 of 29.94 ± 2.24 µM, and down-regulated the expression of COX-2. Compound 1 also induced a statistically significant decrease in the gene expression of various cytokines and chemokines.
Conclusion: These findings showed that the pyrimidine derivative 1 displayed potent anti-inflammatory and anticancer properties in vitro, and can be selected as a lead compound for further investigation.