Tumor cells attract these cells to the microenvironment and alter their functions and phenotypes by secreting chemoattractants, such as MIC-1 (Wu et al., 2010), MCP-1 (Roesch et al., 2018), GM-CSF (Horikawa et al., 2020), S100A8/9 (Gabrilovich and Nagaraj, 2009) and CCL2 (Chang et al., 2016), to create an immunosuppressive milieu that aids in evading anti-tumor immunity. The gene discussed is CCL2; the disease is neoplasm.