STAT1 and STAT4 expression as prognostic biomarkers in patients with bladder cancer

Signal transducer and activator of transcription (STAT) proteins are cytoplasmic transcription factors known to play key roles in numerous physiological and pathological processes, from pathogen response to cancer modulation. However, the roles of some STAT family members, particularly STAT1 and STAT4, in the initiation and progression of bladder cancer (BC) have not been comprehensively studied. The present study investigated the expression pattern of STAT1 and STAT4 in the prognosis and survival of BC taking advantage of patients' specimens and cell lines. In our cohort, high mRNA expression of STAT1 was significantly associated with tumor invasiveness, recurrence and progression, and was shown to increase according to tumor stage in BC cell lines. However, it did not affect patient survival. By contrast, STAT4 exhibited its highest expression in early-stage tumors, without a significant link to the tumor stage. Moreover, it was found that increased STAT4 mRNA expression was associated with improved disease-free survival and overall survival in our cohort. Collectively, these findings suggest that STAT1 and STAT4 could be promising prognostic markers to enhance BC management.