STAT3 activation is associated with cerebrospinal fluid interleukin-10 (IL-10) in primary central nervous system diffuse large B cell lymphoma

Signal transducers and activators of transcription 3 ( STAT3) are activated by various cytokines and oncogenes; however, the activity and pathogenesis of STAT3in diffuse large B cell lymphomaof the central nervous system have not been thoroughly elucidated. We investigated the phosphorylation levels of STAT3in 40 specimens of primary central nervous system diffuse large B-cell lymphoma(PCNS DLBCL) and analyzed the association between phsopho- STAT3(pSTAT3) expression and cerebrospinal fluid (CSF) concentration of interleukin-10(IL-10) or IL-6. Immunohistochemistry and Western blot analysis revealed that most of the specimens in PCNS DLBCL expressed pSTST3 protein, and a strong phosphorylation levels of STAT3was statistically associated with high CSF IL-10 levels, but not with CSF IL-6 levels. Next, we demonstrated that recombinant IL-10 and CSF containing IL-10 induced the phosphorylation of STAT3in PCNS DLBCL cells. Furthermore, molecular subtype classified by Hans’ algorithm was correlated with pSTAT3 expression levels and CSF IL-10 levels. These results suggest that the STAT3activity is correlated with CSF IL-10 level, which is a useful marker for STAT3activity in PCNS DLBCLs.