TY - JOUR
T1 - Effects of siltuximab on the IL-6-induced signaling pathway in ovarian cancer
AU - Guo, Yuqi
AU - Nemeth, Jeffrey
AU - O'Brien, Colin
AU - Susa, Michiro
AU - Liu, Xianzhe
AU - Zhang, Zhan
AU - Choy, Edwin
AU - Mankin, Henry
AU - Hornicek, Francis
AU - Duan, Zhenfeng
PY - 2010/12/1
Y1 - 2010/12/1
N2 - Purpose: To explore potential therapeutic strategies for interrupting the interleukin-6 (IL-6) signaling pathway, we measured IL-6 expression in ovarian cancer tissues, and evaluated the effects of a monoclonal anti-IL-6 antibody; siltuximab (CNTO 328), on levels of IL-6-induced Stat3 phosphorylation, Stat3 nuclear translocation, and Stat3 downstream antiapoptotic genes. We then looked for enhancing paclitaxel sensitivity in multidrug-resistant ovarian cancer cell lines. Experimental Design: Expressions of IL-6 in ovarian cancer patient specimens were assessed by immunohistochemistry. Effects of siltuximab on IL-6-induced activation of Stat3 in an ovarian cancer cell line were determined by Western blot and real-time analysis of Stat3 nucleocytoplasmic translocation. Influence of combination of siltuximab and paclitaxel on tumor growth was evaluated in a xenograft mouse mode in vivo. Results: Metastatic and drug-resistant recurrent tumors have significantly higher IL-6 expression when compared with the matched primary tumors. Siltuximab specifically suppressed IL-6-induced Stat3 phosphorylation and Stat3 nuclear translocation. Treatment with siltuximab significantly decreased the levels of Stat3 downstream proteins such as MCL-1, Bcl-XL, and survivin. Treatment with siltuximab reduced expression of multiple IL-6-induced genes in these cell lines. Furthermore, siltuximab increased the cytotoxic effects of paclitaxel in a paclitaxel resistant ovarian cancer cell line in vitro, but combination therapy with siltuximab did not have a significant effect on paclitaxel resistant tumor growth in vivo. Conclusions: These results show that siltuximab effectively block the IL-6 signaling pathways and IL-6-induced gene expression. Blockage of IL-6 signaling may provide benefits for the treatment of ovarian cancer.
AB - Purpose: To explore potential therapeutic strategies for interrupting the interleukin-6 (IL-6) signaling pathway, we measured IL-6 expression in ovarian cancer tissues, and evaluated the effects of a monoclonal anti-IL-6 antibody; siltuximab (CNTO 328), on levels of IL-6-induced Stat3 phosphorylation, Stat3 nuclear translocation, and Stat3 downstream antiapoptotic genes. We then looked for enhancing paclitaxel sensitivity in multidrug-resistant ovarian cancer cell lines. Experimental Design: Expressions of IL-6 in ovarian cancer patient specimens were assessed by immunohistochemistry. Effects of siltuximab on IL-6-induced activation of Stat3 in an ovarian cancer cell line were determined by Western blot and real-time analysis of Stat3 nucleocytoplasmic translocation. Influence of combination of siltuximab and paclitaxel on tumor growth was evaluated in a xenograft mouse mode in vivo. Results: Metastatic and drug-resistant recurrent tumors have significantly higher IL-6 expression when compared with the matched primary tumors. Siltuximab specifically suppressed IL-6-induced Stat3 phosphorylation and Stat3 nuclear translocation. Treatment with siltuximab significantly decreased the levels of Stat3 downstream proteins such as MCL-1, Bcl-XL, and survivin. Treatment with siltuximab reduced expression of multiple IL-6-induced genes in these cell lines. Furthermore, siltuximab increased the cytotoxic effects of paclitaxel in a paclitaxel resistant ovarian cancer cell line in vitro, but combination therapy with siltuximab did not have a significant effect on paclitaxel resistant tumor growth in vivo. Conclusions: These results show that siltuximab effectively block the IL-6 signaling pathways and IL-6-induced gene expression. Blockage of IL-6 signaling may provide benefits for the treatment of ovarian cancer.
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U2 - 10.1158/1078-0432.CCR-10-1095
DO - 10.1158/1078-0432.CCR-10-1095
M3 - Article
C2 - 20699329
AN - SCOPUS:78650356983
SN - 1078-0432
VL - 16
SP - 5759
EP - 5769
JO - Clinical Cancer Research
JF - Clinical Cancer Research
IS - 23
ER -
