Potential therapeutic role of natural killer cells in cancer

Cancer immunotherapy is a growing field that aims at restoring and enhancing immune function to combat oncogenic conditions. One target of this field is natural killer (NK) cells. Part of innate immunity, NK cells are able to kill tumor cells without previous priming. Results from stem cell transplants containing alloreactive donor NK cells and in vitro work have evidenced a great antitumor potential. In addition, NK cells are likely to interact with dendritic cells, potent antigen-presenting cells, thus forming a bridge between innate and adaptive immunity. This review aims to provide an overview of NK cells with particular emphasis on properties that can and are being targeted in order to potentiate the antitumor activity of these cells.