Across TCGA pan-cancer cohorts, CRP mass-spec protein differs between tumor and matched normal tissue in 3 of 18 cancer types tested, making tumor–normal expression one of CRP’s most consistent transcriptional readouts.
The strongest signal is observed in head and neck squamous cell carcinoma (HNSC), where CRP mass-spec protein is repressed in tumor relative to normal tissue. In most cancer types CRP is over-expressed in tumor, although a few such as HNSC show the opposite, repressed pattern.
HNSC, CCRCC, and LUAD are the cancer types where CRP tumor–normal differential expression is most reproducible.