HLA class I downregulation is It frequent event associated with tumour
invasion and development. Altered HLA class I tumour phenotypes can h
ave profound effects on T-cell and natural killer (NK)-cell antitumour
responses. Here, Federico Garrido and colleagues analyse these altere
d tumour phenotypes in detail, indicating their potential relevance fo
r implementation of immunotherapeutic protocols and strategies to over
come tumour escape mechanisms.