A variety of CXC chemokines, such as CXCL4 [19], CXCL5 [42], CXCL6 [43], CXCL12 [44], CXCL13 [45] and CXCL14 [46], have been shown to be associated with the progression of SSc. This evidence concerns the gene CXCL6 and systemic sclerosis.