IRF4 and neoplasm: On the other hand, IRF4-C99R′s GOF properties are exemplified by the distinct activation of lymphoma-specific gene expression, including GATA3, CCL5, and TNFRSF8. Expression of these genes is stongly associated with the cHL phenotype and they play important roles not only for the tumor cells themselves but also for their interaction with the microenvironment31,53.