Negative argininosuccinate synthetase expression in melanoma tumours may predict clinical benefit from arginine-depleting therapy with pegylated arginine deiminase

• Published in: British journal of cancer Vol. 106; no. 9; pp. 1481 - 1485
• Main Authors: Feun, L G, Marini, A, Walker, G, Elgart, G, Moffat, F, Rodgers, S E, Wu, C J, You, M, Wangpaichitr, M, Kuo, M T, Sisson, W, Jungbluth, A A, Bomalaski, J, Savaraj, N
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 24.04.2012; Nature Publishing Group
• Subjects: 631/208/199; 631/92/436/2388; 692/699/67/1059; 692/699/67/1813/1634; Adult; Aged; Aged, 80 and over; Arginine - deficiency; Argininosuccinate Synthase - metabolism; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Biopsy; Cancer Research; Cancer therapies; Clinical trials; Dermatology; Drug dosages; Drug Resistance; Epidemiology; Female; Humans; Hydrolases - therapeutic use; Liver Neoplasms - drug therapy; Liver Neoplasms - mortality; Liver Neoplasms - secondary; Lung Neoplasms - drug therapy; Lung Neoplasms - mortality; Lung Neoplasms - secondary; Male; Medical prognosis; Medical research; Medical sciences; Melanoma; Melanoma - drug therapy; Melanoma - mortality; Melanoma - pathology; Metastasis; Middle Aged; Molecular Medicine; Oncology; Patients; Polyethylene Glycols - therapeutic use; Skin Neoplasms - drug therapy; Skin Neoplasms - mortality; Skin Neoplasms - pathology; Survival Rate; Toxicity; Translational Therapeutics; Treatment Outcome; Tumors; Tumors of the skin and soft tissue. Premalignant lesions; New York; United States > US; arginine deiminase; melanoma; arginine; Carbon-nitrogen ligases; Enzyme; Argininosuccinate synthase; Malignant tumor; Arginine deiminase; Cancerology; Depletion; Treatment; Ligases; Malignant melanoma; Hydrolases; Predictive factor; Pegylated form; Cancer
• ISSN: 0007-0920; 1532-1827
• DOI: 10.1038/bjc.2012.106

Background: Arginine-depleting therapy with pegylated arginine deiminase (ADI-PEG20) was reported to have activity in advanced melanoma in early phase I–II trial, and clinical trials are currently underway in other cancers. However, the optimal patient population who benefit from this treatment is unknown. Methods: Advanced melanoma patients with accessible tumours had biopsy performed before the start of treatment with ADI-PEG20 and at the time of progression or relapse when amenable to determine whether argininosuccinate synthetase (ASS) expression in tumour was predictive of response to ADI-PEG20. Results: Twenty-seven of thirty-eight patients treated had melanoma tumours assessable for ASS staining before treatment. Clinical benefit rate (CBR) and longer time to progression were associated with negative expression of tumour ASS. Only 1 of 10 patients with ASS-positive tumours (ASS+) had stable disease, whereas 4 of 17 (24%) had partial response and 5 had stable disease, when ASS expression was negative (ASS−), giving CBR rates of 52.9 vs 10%, P =0.041. Two responding patients with negative ASS expression before therapy had rebiopsy after tumour progression and the ASS expression became positive. The survival of ASS− patients receiving at least four doses at 320 IU m − 2 was significantly better than the ASS+ group at 26.5 vs 8.5 months, P =0.024. Conclusion: ADI-PEG20 is safe and the drug is only efficacious in melanoma patients whose tumour has negative ASS expression. Argininosuccinate synthetase tumour positivity is associated with drug resistance and tumour progression.