STAT3 and neoplasm: Anti-IL-6 therapy has the potential to treat tumors by blocking JAK/STAT signaling.50 Although the clinical results thus far have been mixed, this approach continues to be studied in a variety of tumor types.71–73 Meanwhile, the compounds OPB-31121 and OPB-51602 are being studied as STAT3 inhibitors,74, 75 but with some reservations.