Frequent expression of a novel cancer testis antigen, protein kinase human monopolar spindle 1 (hMps1/TTK) in human urinary bladder transitional cell carcinoma.

Abstract

Urothelial bladder cancer (UBC) is a frequently occurring malignancy of the urinary tract. The present study was undertaken to evaluate the mRNA and immunohistochemical (IHC) expression of protein kinase human monopolar spindle 1 (hMps1/TTK) gene in transitional cell carcinoma (TCC) of the bladder and correlate its expression with the clinicopathological characteristics of patients. In the present study, quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR) was used to evaluate TTK mRNA expression in TCC. IHC analysis of TTK was also evaluated. Independent Student's t, ANOVA and chi-square (χ2) tests were used to analyze the data statistically. The frequency of TTK mRNA over expression was detected in 50% of UBC (38/76) by qRT-PCR. Relative mean fold expression of TTK mRNA was found significantly (p < 0.05) higher in muscle-invasive bladder cancer (MIBC) as compared to non-muscle-invasive bladder cancer (NMIBC) patients (8.96 ± 4.51 vs. 5.64 ± 3.53, p = 0.03). Moreover, IHC reveals heterogenous immunostaining pattern of TTK in TCC tissues. The frequency of TTK protein over expression was detected in 56.9% (37 of 65) UBC patients. No significant IHC expression of TTK was detected among adjacent noncancerous tissues (ANCTs) and benign prostatic hyperplasia (BPH) used as control. Collectively our study observations conclude that TTK is a novel cancer/testis antigen (CTA) as a diagnostic marker for early diagnosis of UBC.