For example, CD4 T cells of the “Th 2” type have been shown to enhance the frequency of lung metastases of mammary tumors through their interactions with TAMs (44), and, in a clinical setting, it has been found that the ratio of Th2 over Th1 cells infiltrating a tumor correlates with poor prognosis of patients with pancreatic cancer (45). This evidence concerns the gene CD4 and pancreatic neoplasm.