MAPK8 and rheumatoid arthritis: The results showed that artesunate (60 μM) did not alter the mRNA and protein expression of PI3K and Akt in primary RA-FLS, nor levels of p44/42 MAPK, p38 MAPK, JNK, and p-JNK from MAPK pathway; IKK-α, IKK-β, IκB, p-IκBα, NF-κB p65, and NF-κB p-p65 from NF-κB pathway; or c-fos and c-jun from AP-1 pathway (data not shown).