Another investigation in 2015 by Zhang et al. studied the effect of SIN on proliferation of RA-FLS, and found that SIN has significant anti-proliferative activity on RA-FLS via inhibition of NF-κB and mitogen-activated protein kinase (MAPK) signal pathway through down-regulating MyD88 and TRAF-6 proteins in RA-FLS [83]. This evidence concerns the gene NFKB1 and rheumatoid arthritis.