STAT3 and cancer: Drug strategies to target OSM biological activities fall into four categories: (i) monoclonal antibodies that directly block the cytokine (GSK315234 [100] or GSK2330811 [101]); (ii) cytokine antagonist (Jorcyk et al., date of patent 24 January 2017, Oncostatin M (OSM) antagonist for preventing cancer metastasis and IL-6 related disorders, U.S. Patent USO09550828B2, https://patentimages.storage.googleapis.com/e7/55/a4/026371eca35619/US9550828.pdf); (iii) small molecules targeting LIFRβ (EC359 [102]); (iv) small molecules interfering with OSMR through gp130 and the JAK–STAT3 pathway.