TY - JOUR T1 - Combination of Arginine Deprivation with TRAIL Treatment as a Targeted-Therapy for Mesothelioma JF - Anticancer Research JO - Anticancer Res SP - 6991 LP - 6999 VL - 34 IS - 12 AU - MEDHI WANGPAICHITR AU - CHUNJING WU AU - GREGORY BIGFORD AU - GEORGE THEODOROPOULOS AU - MIN YOU AU - YING YING LI AU - JAVIER VERONA-SANTOS AU - LYNN G. FEUN AU - DAO M. NGUYEN AU - NIRAMOL SAVARAJ Y1 - 2014/12/01 UR - http://ar.iiarjournals.org/content/34/12/6991.abstract N2 - In the present study we present data to show that certain tumor cells including malignant pleural mesothelioma (MPM) cells do not express argininosuccinate synthetase (ASS), and thus are unable to synthesize arginine from citrulline. Exposure of these ASS-negative cells to the arginine degrading enzyme, arginine deiminase (ADI-PEG20), for 72 h results in significant increases in cleaved caspase-3. Importantly, this apoptotic signal is further strengthened by the addition of TNF-related apoptosis-inducing ligand (TRAIL). Using flow cytometry, we showed that the combination treatment (ADI-PEG20 at 50 ng/ml and TRAIL at 10 ng/ml) for 24 h resulted in profound cell death with 67% of cells positive for caspase-3 activity, while ADI-PEG20 alone or TRAIL alone resulted in only 10-15% cell death. This positive amplification loop is mediated through the cleavage of proapototic protein “BID”. Conclusion: Our work represents a new strategy for treating patients with malignant pleural mesothelioma using targeted molecular therapeutics based on selected tumor markers, thus avoiding the use of potentially cytotoxic chemotherapy. ER -