Barone et al. demonstrated that expression of CXCL13 and CCL21 in the salivary glands of SS patients is indicative of reactive lymphoid aggregates and suggestive of their implication in ectopic lymphoid tissue organization, whilst CXCL12 expression predominates in infiltrated ducts and malignant B cells, possibly regulating the survival of malignant B cells [37]. This evidence concerns the gene CXCL13 and synovial sarcoma.