STAT3 and central nervous system cancer: It has been reported that more than 50% p-STAT3 (Try705)-positive immunohistochemical staining in WHO grade III or IV glioma.5 Ser727 phosphorylation is considered a secondary event after Tyr705 phosphorylation.34 In our present study, we also found that the inhibitory effect of CTS on phosphorylation of STAT3 Tyr705 in MGs cells was independent on activation of JAKs.