The expression and clinical significance of ZBTB7 in transitional cell carcinoma of the bladder

Abstract

Zinc finger and BTB domain containing 7A (ZBTB7) is a ZBTB protein family member of transcriptional repressors that serves a critical role in cell transformation and malignancy. However, the association between ZBTB7 expression in bladder cancer tissues and the prognosis of patients remains unclear. The aim of the current study was to detect the expression of ZBTB7 in transitional cell carcinoma (TCC) of the bladder and normal bladder mucous tissues to evaluate the diagnostic and prognostic value of ZBTB7 in TCC of the bladder. A total of 100 TCC specimens were analyzed and the expression of ZBTB7 mRNA was examined via reverse transcription-quantitative polymerase chain reaction. The expression of ZBTB7 protein was examined by western blotting and immunohistochemistry. The association between ZBTB7 expression and the clinical prognosis of patients from the TCGA database was analyzed. High expression of ZBTB7 mRNA and protein in TCC tissue was detected and TCC expression was significantly higher in TCC tissue than in normal bladder mucous tissues (P<0.05). Furthermore, ZBTB7 expression was associated with recurrence, a larger tumor size and higher tumor grade. In terms of overall and recurrence-free survival, the group expressing high levels of ZBTB7 exhibited lower overall and recurrence-free survival compared with the low ZBTB7 expression group, although these differences were not statistically significant. Therefore, ZBTB7 may be important in the initiation and progression of TCC.

Keywords: ZBTB7; prognosis; survival; transitional cell carcinoma of the bladder.

Figure 1.

ZBTB7 expression in patients with TCC. (A) ZBTB7 expression in patients with T1, T2, T3 stage TCC. (B) ZBTB7 expression in potential, low and high grade TCC. (C) ZBTB7 expression in primary and recurrent TCC. TCC, transitional cell carcinoma; ZBTB7, zinc finger and BTB domain containing 7A. **P<0.01, ***P<0.001.

Figure 2.

H&E and IHC staining for ZBTB7 in normal and tumor tissue. (A) H&E and IHC staining for ZBTB7 in normal tissue. ZBTB7 staining was positive only in superficial mucous layer. (B) H&E and IHC staining for ZBTB7 in tumor tissue. ZBTB7 staining was positive throughout the mucous and muscular layers. Left panels, ×100 magnification; middle panels, ×200 magnification; right panel, ×400 magnification. H&E, hematoxylin and eosin; IHC, immunohistochemistry; ZBTB7, zinc finger and BTB domain containing 7A.

Figure 3.

Western blot analysis of levels of ZBTB7 expression in three patients with transitional cell carcinoma. The expression of ZBTB7 protein is markedly increased in tumor tissue. T, transitional cell carcinoma samples; N, normal samples; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; ZBTB7, zinc finger and BTB domain containing 7A.

Figure 4.

Associations between ZBTB7 expression and the clinical prognosis of patients with transitional cell carcinoma. (A) The overall survival curve indicated that patients with high expression of ZBTB7 exhibited lower overall survival levels compared with patients with low ZBTB7 expression. However, this difference between the two groups was not statistically significant (P>0.05). (B) The recurrence-free survival curve indicated that there was a decline in recurrence-free survival in patients exhibiting high expression of ZBTB7. However, there was still no significant difference between two groups (P>0.05). ZBTB7, zinc finger and BTB domain containing 7A.