Fig. 4

In silico analyses show a positive association between hypoxia and PD-L1 in muscle-invasive bladder tumours. Analyses involved microarray data from the BCON trial normalised previously using aroma package and filtered to include only tumours stage 2 and above (n = 142) and the TCGA-BLCA RNASeq2GeneNorm dataset downloaded using the Bioconductor package TCGAutils and filtered to include only tumours of a known stage 2 and above (n = 404). Hypoxia scores were applied to each tumour sample using a previously published 24-gene bladder cancer hypoxia signature. Hypoxia signature scores were plotted against the expression of PD-L1 in A) BCON and C) TCGA cohorts. R² values were calculated using Pearson’s correlation coefficient and the p values represent a linear model analysis. Tumours were stratified into hypoxia low or high using the median of the hypoxia scores for each cohort, and plotted against the PD-L1 expression in the B) BCON and D) TCGA cohorts. P values were calculated using one way ANOVA between the two groups. p values are represented as follows: ns = not significant, * < 0.05, ** < 0.01, *** < 0.001, **** < 0.0001