The present study aimed to evaluate the expression status of Janus kinase (JAK)-Signal Transducer and Activator of Transcription (STAT) in renal cell carcinoma and benign renal tissue, and identify a potential biomarker for interferon (IFN) response prediction. A total of 32 specimens of human renal cell carcinoma and 10 specimens of benign renal tissue were harvested from surgically removed kidneys. The expression levels of JAK-STAT were determined by immunohistochemical staining and

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... ve polymerase chain reaction. Furthermore, the expression levels of JAK-STAT in renal cell carcinoma tissues that were stimulated with IFN-α were quantified by western blot analysis. The positive expression rates of JAK1, STAT1 and phosphorylated (P)-STAT1 in the renal cell carcinomas were significantly lower than that in the benign renal tissues (25.0, 31.2, and 12.5% vs. 70.0, 50.0, and 70.0%, respectively; P<0.05). The relative expression levels of JAK1 (0.696±0.102) and STAT1 mRNA (0.341±0.068) in the tumor tissue were lower than those in the benign tissue (0.957±0.103 and 0.547±0.082, respectively; P<0.05). IFN stimulation enhanced the expression levels of P-STAT1 in the renal cell carcinoma tissues, and enhancement of the P-STAT1 expression levels was associated with tumor relapse and metastasis. In conclusion, P-STAT1 is a potential predictor of IFN response in patients with advanced renal cell carcinoma.