IL6 and Castleman disease: It is known to competitively inhibit IL-6/IL-6R signaling and completely neutralizes IL-6 activities.[8, 9] A series of clinical studies has successfully shown that the suppression of IL-6/IL-6R signaling by tocilizumab is therapeutically effective in alleviate Castleman’s disease and rheumatoid arthritis.[10, 11] Given its success in treating these diseases, tocilizumab may prove useful in treating IL-6–related cancers and we were motivated to elucidate the therapeutic potential of tocilizumab against ovarian cancer.