Abstract 3968: Ovarian cancer chemokine microenvironment is conducive to homing of CD3/CD28 co-stimulated T cells prepared for adoptive transfer therapy.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Chemokines play a central role in lymphocyte trafficking and therefore affect the success of immune therapy by supporting the homing of T cells to the site of disease. We are conducting a phase I study using CD3/CD28 co-stimulated lysate vaccine-primed autologous T cells for advanced ovarian cancer. Papillary serous ovarian cancer is a very heterogeneous tumor and little is known about the expression of chemokines in its microenvironment. We thus mapped the chemokines predominantly expressed in advanced stage papillary serous ovarian cancer and characterized the chemokine receptor expression and homing ability of co-stimulated autologous T-cells of patients participating in our adoptive T cell transfer trial. The expression of all known human chemokines was analyzed on a gene expression array dataset from 63 patients with primary ovarian cancer and validated on publicly available microarray dataset from 222 ovarian cancer samples, as well as on 17 primary ovary cancer lines. Immunohistochemistry for the 10 most highly expressed chemokines from the 3 databases was performed on tissue microarrays constructed from 50 patients with advanced stage papillary serous ovarian cancer. Slides were also stained for CD3+, CD8+ and FoxP3+ T cells. Median expression level of chemokines and T cells were measured at primary and metastatic sites. Vaccine-primed, ex vivo CD3/CD28 co-stimulated autologous T-cells of 5 patients were characterized for chemokine receptors by flow cytometry. Chemotaxis assays were performed to assess the functionality of the receptors. The 10 most highly expressed chemokines found in advanced stage papillary cancer by gene expression analysis were: CCL2, CCL4, CCL5, CCL28, CXCL5, CXCL6 CXCL10, CXCL12, CXCL16 and CX3CL1. Immunohistochemistry confirmed the expression of these chemokines at both primary and metastatic sites. The expression of CCL4 and CCL5 showed the strongest correlation with the presence of tumor-infiltrating CD8+ cells, whereas CCL28, CXCL12, CX3CL1, CXCL5 and CXCL6 expression showed correlation with increased numbers of FoxP3+ cells in tumor islets. The three expressed chemokine receptors on vaccine-primed CD3/CD28 co-stimulated T cells were CCR10 (CCL27, CCL28 receptor), CXCR3 (CXCL9-11 receptor) and CXCR4 (CXCL12 receptor). Chemotaxis assays confirmed the migration of these co-stimulated T cells towards ligands of all three of these receptors. Chemokines play a paramount role in tumor immune response and characterization of the tumor microenvironment is key to successful immunotherapy. Ex vivo expanded tumor specific cytotoxic T cells have shown promising results for the treatment of small-volume disease, and our data confirm that these cells are armed with the appropriate receptors to home to ovarian cancer. Citation Format: Emese Zsiros, Hongzhe Lee, Ian S. Hagemann, Priyanka Duttagupta, Renee Frank, Thomas Garrabrant, Bruce L. Levine, Carl H. June, Janos Tanyi, Lana Kandalaft, Michael Feldman, George Coukos. Ovarian cancer chemokine microenvironment is conducive to homing of CD3/CD28 co-stimulated T cells prepared for adoptive transfer therapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3968. doi:10.1158/1538-7445.AM2013-3968