Abstract
BACKGROUND: Bladder cancer (BC) is recorded as the fifth most common cancer worldwide with high morbidity and mortality. The most urgent problem in BCs is the high recurrence rate as two-thirds of non-muscle-invasive bladder cancer (NMIBC) will develop into muscle-invasive bladder cancer (MIBC), which retains a feature of rapid progress and metastasis. In addition, only a limited number of biomarkers are available for diagnosing BC compared to other cancers. Hence, finding sensitive and specific biomarkers for predicting the diagnosis and prognosis of patients with BC is critically needed. Therefore, this study aimed to determine the expression and clinical significance of urinary lncRNA BLACAT1 as a non-invasively diagnostic and prognostic biomarker to detect and differentiate BCs stages. METHODS AND RESULTS: The expression levels of urinary BLACAT1 were detected by qRT-PCR assay in seventy (70) BC patients with different TNM grades (T0-T3) and twelve (12) healthy subjects as control. BLACAT1 was downregulated in superficial stages (T0 = 0.09 ± 0.02 and T1 = 0.5 ± 0.1) compared to healthy control. Furthermore, in the invasive stages, its levels started to elevate in the T2 stage (1.2 ± 0. 2), and higher levels were detected in the T3 stage with a mean value of (5.2 ± 0.6). This elevation was positively correlated with disease progression. Therefore, BLACAT1 can differentiate between metastatic and non-metastatic stages of BCs. Furthermore, its predictive values are not like to be influenced by schistosomal infection. CONCLUSIONS: Upregulation of BLACAT1 in invasive stages predicted an unfavorable prognosis for patients with BCs, as it contributes to the migration and metastasis of BCs. Therefore, we can conclude that urinary BLACAT1 may be considered a non-invasive promising metastatic biomarker for BCs.