Immune-checkpoint gene expression and BCG response in non-muscle invasive bladder cancer

•CD276 (B7-H3) gene expression is associated with BCG unresponseviness in NMIBC patients.•IDO1 expression is a marker of worse prognosis in NMIBC.•MSI and PD-L1 expressions are not associated with responsiveness of BCG vaccine in NMIBC patients. One-hundred-six patients diagnosed with non-muscle invasive bladder cancer and treated with intravesical BCG were included and divided into two groups, BCG-responsive (n = 47) and -unresponsive (n = 59). Immunohistochemistry was used to evaluate PD-L1 expression and MSI was assessed by a commercial multiplex PCR kit. The mRNA expression profile of 15 immune checkpoints was performed using the nCounter technology. For in silico validation, two distinct cohorts sourced from the Gene Expression Omnibus (GEO) database were used. Among the 106 patients, only one (