In the SSc dataset, the gene up-regulated with CCL2 expression value was enriched mainly in lipid metabolism, such as acyl − CoA metabolic process, cholesterol biosynthetic process, establishment of skin barrier, fatty − acyl − CoA biosynthetic process, fatty acid derivative biosynthetic process, fatty acid derivative metabolic process, mitochondrial protein-containing complex, fatty acid synthase activity, biosynthesis of unsaturated fatty acids, butanoate metabolism, fatty acid degradation, fatty acid elongation and fatty acid metabolism (Fig. 6e–h). The gene discussed is FASN; the disease is systemic sclerosis.