Treatment of prostate cancer cells deficient in argininosuccinate synthetase with siRNAs targeting Beclin-1 or chloroquine (an autophagy inhibitor), has been reported to inhibit autophagy and increase the sensitivity of such cells to treatment with the anti-cancer agent ADI-PEG20, a pegylated arginine deiminase [37]. This evidence concerns the gene BECN1 and prostate cancer.