Prognostic Impact of Canonical TGF-β Signaling in Urothelial Bladder Cancer

oleh: Slavica Stojnev, Miljan Krstić, Jovana Čukuranović Kokoris, Irena Conić, Ivan Petković, Sonja Ilić, Jelena Milosević-Stevanović, Ljubinka Janković Veličković

Format: Article
Diterbitkan: MDPI AG 2019-06-01

Deskripsi

<i>Background and objectives</i>: Dysregulation of TGF-&#946; signaling plays multiple roles in cancer development and progression. In the canonical TGF-&#946; pathway, TGF-&#946; regulates the expression of hundreds of target genes via interaction with Smads, signal transducers and transcriptional modulators. We evaluated the association of TGF-&#946;1, Smad2, and Smad4, the key components of canonical TGF&#946; pathway, with clinicopathologic characteristics of urothelial bladder cancer, and assessed their prognostic value in prediction of patients&#8217; outcome. <i>Materials and Methods</i>: Immunohistochemical analysis of TGF-&#946;1, Smad2, and Smad4 expression was performed on 404 urothelial bladder cancer samples, incorporated in tissue microarrays. Expression status was correlated with clinicopathological and follow-up data. The median follow-up was 61 months. <i>Results</i>: High expression of TGF-&#946;1, Smad2, and Smad4 was detected in 68.1%, 31.7% and 45.2% of the tumors, respectively. TGF-&#946;1 overexpression was significantly associated with high tumor grade, and advanced pathologic stage (<i>p</i> &lt; 0.001, respectively). Conversely, high Smad2 and Smad4 expression was linked to low tumor grade (<i>p</i> = 0,003, <i>p</i> = 0.048, respectively), and low tumor stage (<i>p</i> &lt; 0.001, <i>p</i> = 0.003, respectively). Smad2 showed an inverse correlation with variant morphology and divergent differentiation of urothelial tumors (<i>p</i> = 0.014). High TGF-&#946;1 correlated directly, while Smad2 and Smad4 correlated inversely to cancer-specific death (<i>p</i> = 0.043, <i>p</i> = 0.003, and <i>p</i> = 0.022, respectively). There was a strong relationship between Smad2 and Smad4 expression (<i>p</i> &lt; 0.001). Survival analyses showed that high Smad2 and Smad4 expression was associated with longer overall survival (<i>p</i> = 0.003, <i>p</i> = 0.034, respectively), while in multivariate regression analysis TGF-&#946;1 manifested as an independent predictor of poor outcome. <i>Conclusions</i>: Unraveling the complex roles and significance of TGF-&#946; signaling in urothelial bladder cancer might have important implications for therapy of this disease. Assessment of TGF-&#946; pathway status in patients with urothelial bladder cancer may provide useful prognostic information, and identify patients that could have the most benefit from therapy targeting TGF-&#946; signaling cascade.