Nuclear Expression Of Antizyme Inhibitor Is Associated With Poor Prostate Cancer Prognosis

Novel molecular markers that are associated with prostate cancer progression are needed to provide more useful information for the diagnosis and treatment of this disease. The antizyme inhibitor (AZI), a non-enzymatic homologue of ornithine decarboxylase (ODC), is upregulated in many cancer types, including: prostate cancer, breast cancer, hepatocellular carcinoma and non-small cell lung cancer. In this study, we examined the distribution of AZI in benign prostate tissues and in prostate cancers at differing stages. We were interested specifically in the possible correlation between AZI expression and patient survival. We found that AZI can reside in the cytoplasm and/or nuclear space in prostate cancer tissue. Nuclear AZI was observed in nearly all of the prostate cancer specimens but not in benign prostate tissue. Cytoplasmic AZI was found both in tumor cells and in adjacent benign prostate tissue. Nuclear AZI was associated significantly with prostate-specific antigen recurrence-free survival but not with overall survival. Further, we found that the presence of nuclear AZI could distinguish poor survival in lower grade patients (Gleason score ≤ 7), especially in samples with non-cribriform tumors. Our results demonstrate a potential role for nuclear AZI as an independent marker of patient outcome in prostate cancer patients. Citation Format: Liangzhe Wang, Yingjie Xu, Shulin Wu, Mary Fergus, Chin-Lee Wu, Bruce Zetter. Nuclear expression of antizyme inhibitor is associated with poor prostate cancer prognosis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4340. doi:10.1158/1538-7445.AM2015-4340