Monitoring Tumor Genome Stability - Immunohistochemistry (IHC) for P53

Immunohistochemical assays for p53 aim to assess the status of the p53 protein, a nuclear transcription factor that acts as a guardian of the genome and inhibits tumorigenesis. IHC reveals the accumulation of mutant (non-functional) p53 protein within the nucleus, or the absence of the protein in the case of certain loss-of-function mutations. The expression pattern (strong accumulation or complete absence) is a proxy for the presence of a mutation in the TP53 gene, one of the most common genetic alterations in human cancer.