CXCL12 and Schwartz-Jampel syndrome: The absence of this signal, in association with abundance of survival factors (TNFSF13B, TNFSF14), inflammatory cytokines and chemokines (CXCL9, CXCL12) and costimulatory molecules (ICOS), unveiled by our analysis could explain the occurrence of malignant clone escape that has been described TLS and is responsible for the increased frequency in development of mucosal associated lymphoid tissue lymphoma observed in SjS.