title: 2-aryl benzimidazole conjugate induced apoptosis in human breast cancer MCF-7 cells through caspase independent pathway.
abstract: Apoptosis is a representative form of programmed cell death, which has been assumed to be critical for cancer prevention. Thus, any agent that can induce apoptosis may be useful for cancer treatment and apoptosis induction is arguably the most potent defense against cancer promotion. In our previous studies, 2-aryl benzimidazole conjugates were synthesized and evaluated for their antiproliferative activity and one of the new molecule (2f) was considered as a potential lead. This lead molecule showed significant antiproliferative activity against human breast cancer cell line, MCF-7. The results of the present study revealed that this compound arrested the cell cycle at G2/M phase. Topoisomerase II inhibition assay and Western blot analysis suggested that this compound effectively inhibits topoisomerase II activity which leads to apoptotic cell death. Apoptosis induction in MCF-7 cells was further confirmed by loss of mitochondrial membrane potential (∆Ψm), release of cytochrome c from mitochondria, an increase in the level of apoptosis inducing factor (AIF), generation of reactive oxygen species (ROS), up regulation of proapoptotic protein Bax and down regulation of anti apoptotic protein Bcl-2. Apoptosis assay using Annexin V-FITC assay also suggested that this compound induced cell death by apoptosis. However, compound 2f induced apoptosis could not be reversed by Z-VAD-FMK (a pan-caspase inhibitor) demonstrated that the 2f induced apoptosis was caspase independent. Further, 2f treatment did not activate caspase-7 and caspase-9 activity, suggesting that this compound induced apoptosis in breast cancer cells via a caspase independent pathway. Most importantly, this compound was less toxic towards non-tumorigenic breast epithelial cells, MCF-10A. Furthermore, docking studies also support the potentiality of this molecule to bind to the DNA topoisomerase II.
authors: Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India.
authors: V Lakshma
authors: VL
authors: Nayak
authors: CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500007, India.
authors: Narayana
authors: N
authors: Nagesh
authors: Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India.|Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, 500037, India.
authors: A
authors: A
authors: Ravikumar
authors: Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India.|Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, 500037, India.
authors: Chandrakant
authors: C
authors: Bagul
authors: Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India.
authors: M V P S
authors: MVPS
authors: Vishnuvardhan
authors: Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India.
authors: Vunnam
authors: V
authors: Srinivasulu
authors: Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500007, India. ahmedkamal@iict.res.in.|Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, 500037, India. ahmedkamal@iict.res.in.
authors: Ahmed
authors: A
authors: Kamal
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D051033:Apoptosis Inducing Factor / Q000235:genetics; D001562:Benzimidazoles / Q000008:administration & dosage* / Q000737:chemistry; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D061945:Caspase Inhibitors / Q000008:administration & dosage / Q000737:chemistry; D020169:Caspases / Q000235:genetics; D049109:Cell Proliferation / Q000187:drug effects; D004250:DNA Topoisomerases, Type II / Q000737:chemistry* / Q000235:genetics; D005260:Female; D006801:Humans; D061986:MCF-7 Cells; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000235:genetics; D062105:Molecular Docking Simulation; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: C494829:AIFM1 protein, human; D051033:Apoptosis Inducing Factor; C494826:BAX protein, human; D001562:Benzimidazoles; D061945:Caspase Inhibitors; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; C031000:benzimidazole; D020169:Caspases; D004250:DNA Topoisomerases, Type II
keywords: Annexin V-FITC and apoptosis; Anticancer activity; Topoisomerase II; Western blot analysis