Transcriptome sequencing identifies ANLN as a promising prognostic biomarker in bladder urothelial carcinoma

The prognosis of bladder urothelial carcinoma (BLCA) varies greatly even for patients with similar pathological characteristics. We conducted transcriptome sequencing on ten pairs of BLCA samples and adjacent normal tissues to identify differentially expressed genes. Anillin (ANLN) was identified as a transcript that was significantly up-regulated in BLCA samples compared with normal tissues. Prognostic power of candidate gene was studied using qRT-PCR and immunohistochemistry on 40 and 209 patients, respectively. Patients with elevated ANLN expression level was correlated with poorer cancer-specific (median, 22.4 vs. 37.3 months, p = 0.001), progression-free (median, 19.7 vs. 27.9 months, p = 0.001) and recurrence-free survival (median, 17.1 vs. 25.2 months, p = 0.011) compared with low ANLN expression. Public datasets TCGA and NCBI-GEO were analyzed for external validation. Knockdown of ANLN in J82 and 5637 cells using small interfering RNA significantly inhibited cell proliferation, migration, and invasion ability. Moreover, knockdown of ANLN resulted in G2/M phase arrest and decreased expression of cyclin B1 and D1. Microarray analysis suggested that ANLN played a major role in cell migration and was closely associated with several cancer-related signaling pathways. In conclusion, ANLN was identified as a promising prognostic biomarker which could be used to stratify different risks of BLCA.