To examine the source of serum CXCL1 in 3LL tumor-bearing mice, we first examined the expression and secretion of CXCL1 in 3LL cells and found that 3LL cells constitutively secreted and expressed high level of CXCL1 (Figures 1(b) and 1(c)). The gene discussed is CXCL1; the disease is neoplasm.