By studying transgenic mouse models of skin, lung, breast, and pancreas cancer development, Prof Coussens and her team have shown that adaptive leukocytes differentially regulate myeloid recruitment by organ-dependent mechanisms and that these myeloid cells can prevent CD8+ T cells from killing the tumour in maintaining a microenvironment that allows the tumour to continue to thrive and spread. The gene discussed is CD8A; the disease is neoplasm.