Further, immunofluorescence (IF) analysis of both tumors from KPC-CCR2–/– mice and tumors treated with combination therapy showed a profound decrease in TNF-α levels (Figure 9, A and B), again supporting the conclusion that tumor-infiltrating bone marrow–derived TAMs are a primary source of TNF-α in PDA. The gene discussed is TNF; the disease is Patent ductus arteriosus.