This Article Full Text Full Text (PDF) Supplementary Data Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Bharadwaj, U. Articles by Yao, Q. Search for Related Content PubMed PubMed Citation Articles by Bharadwaj, U. Articles by Yao, Q.

Elevated Interleukin-6 and G-CSF in Human Pancreatic Cancer Cell Conditioned Medium Suppress Dendritic Cell Differentiation and Activation

¹ Molecular Surgeon Research Center, Michael E. DeBakey Department of Surgery and ² Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas

Requests for reprints: Qizhi (Cathy) Yao, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, One Baylor Plaza, NAB 2010, Houston, TX 77030. Phone: 713-798-1765; Fax: 713-798-1705; E-mail: qizhiyao{at}bcm.edu.

Although dendritic cell (DC) function is impaired in pancreatic cancer patients, the underlying mechanisms are unknown. This study analyzed the soluble factors released by pancreatic cancer cells responsible for inhibiting DC differentiation and activation. Medium conditioned by a highly metastatic human pancreatic cancer cell line BxPC-3 [BxPC-3 conditioned medium (BxCM)] was mainly used for the study. Both CD34⁺ hematopoietic progenitor cell–derived and CD14⁺ monocyte-derived immature DCs and mature DCs (mDCs) were inhibited by BxCM. Allostimulation of CD4⁺ and CD8⁺ T cells by BxCM-treated mDCs was inefficient and resulted in production of lower levels of Th1 and Th2 cytokines. Antigen-specific T-cell activation capability was also reduced in BxCM-treated mDCs. Addition of exogenous interleukin-6 (IL-6) and granulocyte colony-stimulating factor (G-CSF), which were present in high amounts in BxCM, mimicked the inhibitory effect of BxCM on DC differentiation and maturation. IL-6 was able to suppress DC differentiation and G-CSF mainly acted on the suppressing allostimulatory capacity of DCs. In addition, pancreatic cancer patient sera were able to inhibit DC differentiation of CD14⁺ monocytes obtained from healthy donors. Depleting IL-6 or G-CSF from BxCM could reverse the DC-inhibitory properties of BxCM. Furthermore, BxCM, IL-6, or G-CSF led to the activation of signal transducer and activator of transcription 3 (STAT3) in CD14⁺ monocytes to different degrees. Blocking BxCM-induced STAT3 activation also reversed the inhibitory effect of BxCM on DC differentiation. Therefore, IL-6 and G-CSF in BxCM represent two main factors responsible for suppression of DC differentiation, maturation, and antigen presentation, and this suppression of DC functions may be due to the aberrant activation of STAT3 by BxCM. [Cancer Res 2007;67(11):5479–88]

This article has been cited by other articles:

				E. Tassi, F. Gavazzi, L. Albarello, V. Senyukov, R. Longhi, P. Dellabona, C. Doglioni, M. Braga, V. Di Carlo, and M. P. Protti Carcinoembryonic Antigen-Specific but Not Antiviral CD4+ T Cell Immunity Is Impaired in Pancreatic Carcinoma Patients J. Immunol., November 1, 2008; 181(9): 6595 - 6603. [Abstract] [Full Text] [PDF]

				H. van Cruijsen, A. A.M. van der Veldt, L. Vroling, D. Oosterhoff, H. J. Broxterman, R. J. Scheper, G. Giaccone, J. B.A.G. Haanen, A. J.M. van den Eertwegh, E. Boven, et al. Sunitinib-Induced Myeloid Lineage Redistribution in Renal Cell Cancer Patients: CD1c+ Dendritic Cell Frequency Predicts Progression-Free Survival Clin. Cancer Res., September 15, 2008; 14(18): 5884 - 5892. [Abstract] [Full Text] [PDF]

				H. Shiraishi, H. Yoshida, K. Saeki, Y. Miura, S. Watanabe, T. Ishizaki, M. Hashimoto, G. Takaesu, T. Kobayashi, and A. Yoshimura Prostaglandin E2 is a major soluble factor produced by stromal cells for preventing inflammatory cytokine production from dendritic cells Int. Immunol., September 1, 2008; 20(9): 1219 - 1229. [Abstract] [Full Text] [PDF]