Preliminary study on the role of the CSMD2 gene in bladder cancer

CSMD2 has been reported as a potential prognostic factor in several cancers. However, whether CSMD2 affects bladder cancer (BC) remains unclear.

Public data were obtained from the TCGA (https://cancergenome.nih.gov) databases. CSMD2expression and its prognostic value were analyzed using bioinformatics methods. CSMD2 mRNA level in patients with BC and BC cell lines was evaluated via quantitative reverse transcriptase polymerase chain reaction. CSMD2 protein level in patients with BC was evaluated via immunohistochemistry. BC cell lines T24 and UMUC-3 were selected for loss-of-function assays targeting CSMD2. Cell viability was determined by CCK8 and clone formation experiments. Cell migration and invasion were evaluated using Transwell assays. Furthermore, the transcriptome of UMUC-3 with CSMD2 knockdown was sequenced to analyze potential signaling network pathways. Finally, the TIMER2.0 database was employed to identify the correlation between CSMD2 and immune cells in the tumor microenvironment.

CSMD2 expression was up-regulated in BC tissues compared to adjacent tissues. High CSMD2 expression was associated with poor survival and could serve as an independent predictor for survival in patients with BC. Furthermore, down-regulation of CSMD2 notably restrained the viability, migration, and invasion abilities of T24 and UMUC-3 cells. Moreover, transcriptomic sequencing after CSMD2 knockdown in UMUC-3 cells revealed its involvement in the regulation of the malignant phenotype in BC. Finally, public databases suggest a connection between CSMD2 and immune cell infiltration in BC.

These findings suggest that CSMD2 may promote proliferation and tumorigenicity, and could represent a potential target for improving the prognosis of BC.