High Expression of Derlin-1 Is Associated with the Malignancy of Bladder Cancer in a Chinese Han Population.

Derlin-1 is overexpressed in various types of solid tumors and has an important function in cancer progression. However, its expression pattern in and association with the clinicopathological characteristics of human bladder cancer remain unclear. In the present study, 3 pairs of fresh samples of bladder cancer tissue and paracancerous tissue were first detected by liquid chromatography tandem mass spectrometry (UPLC-MS/MS) to screen for differentially expressed proteins. Following bioinformatics analysis and assessments by qRT-PCR and western blotting, Derlin-1 was selected as a candidate protein and was then validated in samples from patients with bladder cancer by immunohistochemistry and western blotting. The results showed that the bladder cancer tissues exhibited higher levels of Derlin-1 expression than the paracancerous tissues (P < 0.05). Positive expression of Derlin-1 was significantly correlated with tumor stage, histological grade, and lymph node metastasis (P < 0.001) but was not correlated with other clinicopathological parameters including patient age (P = 0.758) and gender (P = 0.831). Besides, Derlin-1 was highly expressed in BC cell lines (um-uc-3 and T24), and the interference of Derlin-1 could reverse EMT progression, inhibit the tumor migration and invasion in T24 cells. Further, patients with positive Derlin-1 expression had shorter overall survival than those with negative expression (P < 0.001). Taken together, our results demonstrated that Derlin-1 was overexpressed in bladder cancer and was associated with the malignancy of bladder cancer.