J Cancer 2017; 8(8):1347-1354. doi:10.7150/jca.18450 This issue Cite
Research Paper
1. Division of Pulmonology, Department of Internal Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea;
2. Division of Pulmonology, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea;
3. Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea;
4. Department of Life Science and Pharmaceutical Science, Ewha Womans University, Seoul, Korea;
5. WCU Department of Molecular Medicine and Biopharmaceutical Sciences, Seoul National University, Suwon, Korea.
Aminoacyl-tRNA synthetase-interacting multi-functional protein 2 (AIMP2) works as potent tumor suppressor, while its splicing variant lacking exon 2 (AIMP2-DX2) competes with AIMP2 for binding to target proteins and compromises its anti-tumor activity. Assuming that AIMP2 and its variant AIMP2-DX2 could be released out to human sera in pathological condition, we investigated the diagnostic and prognostic usefulness of autoantibodies against AIMP2 and AIMP2-DX2 by measuring their serum levels in 80 normal and lung cancer samples that were matched in age, gender and smoking status. The area under the curve of AIMP2-DX2, AIMP2, and AIMP2-DX2/AIMP2 autoantibody ratio was low (0.416, 0.579, and 0.357, respectively), suggesting limited diagnostic value. A total of 165 lung cancer patients were classified into low and high AIMP2-DX2, AIMP2, and AIMP2-DX2/AIMP2 based on the median expression of each parameter. The high AIMP2-DX2 group was older and had larger tumors (>3 cm) than the low AIMP2-DX2 group. The high AIMP2-DX2/AIMP2 group had higher CYFRA-21 levels and significantly shorter overall survival than the low AIMP2-DX2/AIMP2 group (18.6 vs. 48.9 months, P = 0.021, Log Rank Test). Taken together, autoantibodies against AIMP2-DX2 and AIMP2 are detectable in the human blood and the increased ratio of AIMP2-DX2/AIMP2 is related to poor clinical outcome of lung cancer.
Keywords: Aminoacyl t-RNA synthetase (ARS), Aminoacyl t-RNA synthetase-interacting multi-functional protein 2 (AIMP2), Aminoacyl t-RNA synthetase-interacting multi-functional protein 2-exon 2 deletion (AIMP2-DX2), Autoantibody, Lung cancer.