Nicotinamide N-methyltransferase protein expression in renal cell cancer
Jun ZHANG, Xin-you XIE, Su-wen YANG, Jin WANG, Chao HE
Department of Clinical Laboratory, Sir Run Run Show Hospital, School of Medicine, Zhejiang University, Hangzhou 310016, China; Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou 310016, China; Department of Pathology, Sir Run Run Show Hospital, School of Medicine, Zhejiang University, Hangzhou 310016, China; Biomedical Research Center, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310016, China; Department of Colorectal Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310016, China
jameszhang2000@163.com; drhe_srrsh@sina.com
Abstract: Objective: To understand the function of nicotinamide N-methyltransferase (NNMT) protein as tumor biomarker in renal carcinoma. Methods: Recombinant NNMT protein was used to prepare monoclonal antibodies by hybridoma technique. The diagnostic and prognostic function of NNMT protein in renal carcinoma was evaluated by analyzing 74 renal cancer tissues through immunohistochemical staining for NNMT by using the prepared antibodies. Results: Two hybridomas named 2F8 and 1E7 stably secreting the monoclonal antibodies were isolated successfully, and characters such as isotypes and specificity were determined. NNMT protein was significantly up-regulated in renal cancer and significantly associated with tumor histology and ages. The univariate survival analysis demonstrated that the pT-status, high levels of NNMT, and distant metastasis were significant prognosticators. Conclusion: NNMT is over-expressed in a large proportion in renal cell cancers. High NNMT expression is significantly associated with unfavorable prognosis. However, the prognostic value of NNMT needs further verification in larger sample sizes.