ABSTRACT
Side population (SP) cells mediate chemoresistance in leukemia. However, chemical inhibition approach to target SP cells has been poorly studied. Herein, we report the discovery of isatin derivatives of nicotinic acid amide as potent side population cell inhibitors. The selected derivatives showed superior potency over the reference drug verapamil. Furthermore, the treatment increased chemosensitivity and inhibited the cell proliferation on three different leukemic cell lines, K562, THP-1 and U937, suggesting that both SP and the bulk of leukemic cells are affected. Moreover, treatment with the most potent compound Nic9 reduced the expression of ABCG2, demonstrating that side population inhibition effect of the target derivatives is at least via ABCG2 inhibition. Importantly, the target derivatives induced erythrocyte/dendritic differentiation to leukemic cells mainly through Musashi/Numb pathway modulation.
Subject(s)
Isatin/pharmacology , Leukemia/drug therapy , Niacinamide/pharmacology , Side-Population Cells/drug effects , ATP Binding Cassette Transporter, Subfamily G, Member 2 , ATP-Binding Cassette Transporters/antagonists & inhibitors , ATP-Binding Cassette Transporters/physiology , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Resistance, Neoplasm , Humans , Leukemia/pathology , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/physiology , Neoplastic Stem Cells/drug effects , Nerve Tissue Proteins/analysis , Receptors, Nerve Growth Factor/analysisABSTRACT
Four new complexes of Hg (II), Pb (II), Sn (II) and Bi (III) with indomethacin drug ligand (IMC) were synthesized and characterized by using infrared, electronic, 1H-NMR spectral, thermogravimetric and conductivity measurements. The IMC was found to act as bidentate chelating agent. IMC complexes coordinate through the oxygen of the carboxyl group. The molar ratio chelation is 1:2 (M2+:IMC) with general formula [M (IMC) 2], nH2O for Hg (II), Pb(II) and Sn(II), but 1:3 for Bi(III) ions. Antibacterial screening of these heavy metal complexes against Escherichia coli (Gram-ve), Bacillus subtilis (Gram +ve) and anti-fungi (Asperagillus oryzae, Asperagillus niger, Asperagillus Flavus) were investigated. In the present study, we found evidence suggesting that Bi+3/IMC possesses the capacity to protect the stomach, sperm, testes, cellular ATP, cellular NAD, INSL3, PGD2, PGE2 and antioxidant enzymes from deleterious actions of IMC.
