Although macrophages as well as fibroblasts and tumor cells contribute to this upregulation of Pdgfc expression in TB aged lungs, our findings are recapitulated in a dormancy model using human ER+ ZR-75-1 cells in immunocompromised mice, indicating that PDGF-C can elicit its pro-metastatic effects in an immune-independent manner. The gene discussed is PDGFC; the disease is tuberculosis.