The silencing of argininosuccinate synthetase 1 (ASS1) is a common occurrence in many solid and liquid tumors, as many sarcomas, melanomas, bladder cancers, prostate cancers, small cell lung cancers (SCLC), hepatocellular carcinomas, and leukemias are deficient in this enzyme (1–7). The gene discussed is ASS1; the disease is sarcoma.