Irfan Ahmad - Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
Safia Irfan - Department of Physiology, College of Medicine, King Khalid University, Abha, Saudi Arabia
Mirza Masroor Ali Beg - Department of Biochemistry, Maulana Azad Medical College, New Delhi, India
Hosam Kamli - Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
Syed Parveen Ali - Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia.
Naseem Begum - Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
. Mohammad Alshahrani - Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
Prasanna Rajagopalan - Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia

Objective(s): The Inhibitors of Apoptosis (IAPs) regulate initiator and effector phases of caspase mediated apoptosis. This study evaluates the effects of SMAC mimetic AT-۱۰۱ in regulation of IAPs/caspases/NFƙB-p۶۵ in an adenocarcinoma cell line.Materials and Methods: MTT assay was performed in the NCI-H۵۲۲ cell line. Flow cytometry was used for detecting cell cycle, apoptosis, and NFƙB-p۶۵ regulation.  Effects of AT-۱۰۱ on IAPs and caspases were determined by quantitative real time-PCR and western blotting. AutoDock-VINA was used for computational analysis.    Results: AT-۱۰۱ reduced the cell proliferation of NCI-H۵۲۲ with a GI۵۰ value of ۷ μM. The compound arrested adenocarcinoma cells in the G۱ phase of the cell cycle and increased early and late phase apoptosis while decreasing tumor-cell trans-migration. AT-۱۰۱ treatment to NCI H۵۲۲ at a concentration of ۰.۳۵ μM decreased XIAP, cIAP-۱, and cIAP-۲ mRNA levels to ۴.۳۹±۰.۶۶, ۱.۹۳±۰.۲۶, and ۲.۲۰±۰.۲۴ folds, respectively. Increased dose of AT-۱۰۱ at ۰.۷ μM concentration further decreased XIAP, cIAP-۱, and cIAP-۲ mRNA levels to ۲.۴۴±۰.۶۷, ۱.۴۶±۰.۹۳, and ۰.۹۷±۰.۱۰ folds, respectively.  Similar effects of a dose-dependent decrease in the protein expressions of XIAP, cIAP-۱, and cIAP-۲ were observed with AT-۱۰۱ treatments, while a dose-responsive increase in the mRNA and protein expression levels of caspase ۶ and caspase ۷ was observed in the NCI-H۵۲۲ cell line. The compound exhibited binding affinity (-۶.۱ kcal/mol) and inhibited NFƙB-p۶۵ in these cells. Conclusion: AT-۱۰۱ had anti-tumor efficacy against lung adenocarcinoma cells which could be mediated through IAPs/caspase-dependent apoptosis and NFƙB-p۶۵ cross talk. Results from this study suggests a signal cross talk between IAPs and NFkB and open new channels for further investigations in therapeutic intervention against lung cancer management.

AT-۱۰۱, Caspases, IAPs, NCI-H۵۲۲, NFƙB, SMAC mimetic