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- Hoffmann, Thomas K, et al.
(författare)
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A novel mechanism for anti-EGFR antibody action involves chemokine-mediated leukocyte infiltration.
- 2009
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 124:11, s. 2589-96
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Tidskriftsartikel (refereegranskat)abstract
- Overexpression of the epidermal growth factor receptor (EGFR) is a hallmark of squamous cell carcinoma of the head and neck (SCCHN). Monoclonal antibodies (mAbs) against EGFR are currently used for therapy of recurrent or metastatic disease; however, their mode of action is not completely understood. To investigate the immunological effects of anti-EGFR mAb, we generated a three-dimensional spheroid model of EGFR-expressing SCCHN and used this model to study the effect of anti-EGFR mAb on leukocyte migration toward tumors. Pretreatment with the blocking anti-EGFR mAb EMD 72000, its F(ab')2 fragments or an EGFR tyrosine kinase inhibitor led to substantially increased leukocyte infiltration into EGFR overexpressing tumor spheroids, but not into those with low EGFR expression. Nonblocking anti-EGFR mAb or fibroblast-specific mAb did not affect leukocyte infiltration, suggesting that the observed increase in leukocyte infiltration depends on interference with EGFR activation. Using a human cytokine macroarray, we demonstrated that the blockade of EGFR by anti-EGFR mAb in EGFR-overexpressing SCCHN cells leads to differential expression of several cytokines and chemokines, including the chemokine MCP-1/CCL-2. The significant upregulation of MCP-1/CCL2 on exposure to anti-EGFR mAb was confirmed by quantitative PCR and enzyme-linked immunospot analyses. Moreover, blocking anti-MCP-1 antibody inhibited leukocyte migration toward tumor cells induced by anti-EGFR mAb, pointing to an important role of MCP-1/CCL2 in anti-EGFR mAb-induced leukocyte migration. Our findings demonstrate that anti-EGFR mAb induces leukocyte infiltration to tumor spheroids by upregulating chemokine expression. This novel mechanism for anti-EGFR mAb action may contribute to the antitumor effects of anti-EGFR mAb in vivo.
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- Loskog, Angelica, et al.
(författare)
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In vitro activation of cancer patient-derived dendritic cells by tumor cells genetically modified to express CD154
- 2002
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Ingår i: Cancer Gene Therapy. - 0929-1903 .- 1476-5500. ; 9:10, s. 846-853
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Triggering of CD40 on antigen-presenting cells via its ligand CD154 is an important event in the initial phase of an immune response against cancer cells. In this study, we investigated the effects of adenoviral CD154 immunomodulatory gene therapy on the activation of human dendritic cells (DCs) in a well-defined in vitro system. EXPERIMENTAL DESIGN: Human bladder cancer cell lines and tumor cells from patients with renal cell carcinoma (RCC) were transduced with Ad-CD154 vectors or control vectors. Activation of human in vitro generated DCs after coculture with transduced tumor cells was analyzed. Therapeutic efficacy and cytotoxic T-lymphocyte (CTL) activity were assessed in a subcutaneous (s.c.) murine bladder cancer model. RESULTS: Human bladder cancer cell lines expressing CD154 showed a decreased growth rate, increased apoptosis, and modulated expression of molecules important for recognition by cytotoxic lymphocytes. Further, CD154-expressing allogeneic bladder tumor cell lines and autologous tumor cells from patients with renal cell cancer induced maturation of DCs and stimulated IFN-gamma production from lymphocytes cocultured with mature DCs. In vivo studies showed that CD154 gene therapy was highly effective in wild-type mice but only minimally effective in nude mice. Consequently, strong tumor-specific CTL activity was detected in mice vaccinated with tumor cells expressing CD154. CONCLUSIONS: Using tumor cell lines as well as patient-derived material, we could show that tumor cells expressing CD154 efficiently induce maturation and activation of DCs as well as activation of lymphocytes. Our murine in vivo studies demonstrate that lymphocytes contribute to the observed antitumor effect in a s.c. bladder tumor model. These studies should stimulate CD154 gene therapy approaches for the treatment of urologic malignancies.
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