Fractalkine (CX3CL1)– and Interleukin-2–Enriched Neuroblastoma Microenvironment Induces Eradication of Metastases Mediated by T Cells and Natural Killer Cells

Abstract

Fractalkine (FKN) is a unique CX3C chemokine (CX3CL1) known to induce both adhesion and migration of leukocytes mediated by a membrane-bound and a soluble form, respectively. Its function is mediated through CX3C receptor (CX3CR), which is expressed by T H 1 immune cells including T cells and natural killer (NK) cells. FKN was shown to be expressed in >90% of 68 neuroblastoma samples as determined by cDNA microarray analysis. Here, we characterized the effect of FKN in the neuroblastoma microenvironment using a syngeneic model genetically engineered to secrete FKN. We show FKN-mediated migration, adhesion, and IFN-; secretion of immune effector cells, but limited antineuroblastoma activity, in vitro and in vivo. Therefore, we tested the hypothesis that a combined increase of FKN and interleukin-2 (IL-2) in the neuroblastoma microenvironment induces an effective antitumor immune response. For this purpose, IL-2 was targeted to ganglioside GD2, which is highly expressed on neuroblastoma tissue, using an anti-GD2 antibody IL-2 immunocytokine (ch14.18-IL-2). Only mice bearing FKN-and IL-2-enriched neuroblastoma tumors exhibited a reduction in primary tumor growth and a complete eradication of experimental liver metastases. The depletion of T cells and NK cells in vivo abrogated the effect, and these effector cells showed the highest cytolytic activity in vitro. Finally, only the FKN-and IL-2-enriched neuroblastoma microenvironment resulted in T-cell activation and the release of proinflammatory cytokines. In summary, we showed for the first time the immunologic mechanisms by which targeted IL-2 treatment of neuroblastoma with an FKN-rich microenvironment induces an effective antitumor response. [Cancer Res 2007;67(5):2331-8]

Transcriptome analysis in mouse tumors induced by Ret-MEN2/FMTC mutations reveals subtype-specific role in survival and interference with immune surveillance

“…Previous reports have demonstrated that the antitumor effects elicited by fractalkine gene transfer into subcutaneously implanted murine cancer cell lines depend on NK and T cells (Guo et al 2003, Lavergne et al 2003, Xin et al 2005. Consistent with our data, high endogenous fractalkine expression in neuroblastoma (Zeng et al 2007), colorectal cancer (Ohta et al 2005), and gastric adenocarcinoma (Hyakudomi et al 2008), where it is mainly observed in the plasma membrane and cytoplasm of tumor cells, correlated with a higher density of tumor-infiltrating immune cells. In case of RET oncogene-induced tumors, this activation is dependent on the kind of RET mutation, since fractalkine is not expressed in MEN2B tumors lacking immune infiltrates.…”

“…In support of a potential NK-and/or T-cell-mediated antitumor immune response to RET/FMTC expressing cells, a number of genes that are highly upregulated in RET/FMTC tumors code for apoptosis molecules such as Fas ligand (FasL), perforin 1 (Prf1), and the majority of murine granzymes (Gzma, Gzmb, Gzmc, Gzmd, Gzme, Gzmf, Gzmg, Gzmk, Gzmn). Seven genes encode cytokines, cytokine receptors, or chemokines (IL15, Il2rb, Il2rg, Il12rb1, Il18rap, Icos, Vav3, and Cx3cl1) critically involved in the stimulation of T-and NK-cell proliferation and their recruitment in cancerous tissues (Allavena et al 1997, Kuniyasu et al 2001, Dimberg et al 2007, Zeng et al 2007). Ten upregulated genes in this category code for signaling molecules (e.g.…”

Xenogeneic immunization with human tyrosine hydroxylase DNA vaccines suppresses growth of established neuroblastoma

“…Determination of TH Expression in NB Patients TH expression was detected as described previously (27). Briefly, a cohort of 67 primary NBs profiled with the use of Affymetrix Gene Arrays was reanalyzed for expression of TH.…”

Survivin minigene DNA vaccination is effective against neuroblastoma

“…Then, lysis of NXS2-target cells was determined in a standard 51 Cr-release assay. 36 Lysis was calculated as follows: (sample release -spontaneous release)/ (maximum release-spontaneous release) 3 100 per cent.…”

“…Infiltration of primary tumors (NXS2) by T cells was analyzed using anti-CD8 antibody (53-6.7) and anti-CD4 antibody (RM4-5) (BD Pharmingen, Heidelberg, Germany) as previously described. 36 The average number of infiltrating T cells per lm 2 of tumor tissue was quantified by light microscopy analyzing 20 squares of 0.25 lm 2 at a magnification of 2003.…”