Disruption of Ras binding to PI3K, either constitutively or just in host tissues, severely impairs the recruitment of F4/80+ macrophages to tumors in K-Ras-driven lung tumors [164,320], and the few TAMs present in the tumors are closer to an M1 phenotype, which is associated with good prognosis in context of cancer [320]. The gene discussed is KRAS; the disease is cancer.