In this study we showed that inhibiting naive CD4+ T cell recruitment by knocking down PITPNM3 in tumor-bearing humanized mice could reduce TI Tregs, restore immune killing of tumors and suppress tumor growth and metastases, confirming the role of PITNM3 recognition of CCL18 in TI Treg biogenesis. This evidence concerns the gene PITPNM3 and neoplasm.