Increasing the Clinical Efficacy of NK and Antibody-Mediated Cancer Immunotherapy: Potential Predictors of Successful Clinical Outcome Based on Observations in High-Risk Neuroblastoma

Department of Human Oncology, University of Wisconsin Madison Madison, WI, USA.
Frontiers in Pharmacology (Impact Factor: 3.8). 05/2012; 3:91. DOI: 10.3389/fphar.2012.00091
Source: PubMed


Disease recurrence is frequent in high-risk neuroblastoma (NBL) patients even after multi-modality aggressive treatment [a combination of chemotherapy, surgical resection, local radiation therapy, autologous stem cell transplantation, and cis-retinoic acid (CRA)]. Recent clinical studies have explored the use of monoclonal antibodies (mAbs) that bind to disialoganglioside (GD(2)), highly expressed in NBL, as a means to enable immune effector cells to destroy NBL cells via antibody-dependent cell-mediated cytotoxicity (ADCC). Preclinical data indicate that ADCC can be more effective when appropriate effector cells are activated by cytokines. Clinical studies have pursued this by administering anti-GD(2) mAb in combination with ADCC-enhancing cytokines (IL2 and GM-CSF), a regimen that has demonstrated improved cancer-free survival. More recently, early clinical studies have used a fusion protein that consists of the anti-GD(2) mAb directly linked to IL2, and anti-tumor responses were seen in the Phase II setting. Analyses of genes that code for receptors that influence ADCC activity and natural killer (NK) cell function [Fc receptor (FcR), killer immunoglublin-like receptor (KIR), and KIR-ligand (KIR-L)] suggest patients with anti-tumor activity are more likely to have certain genotype profiles. Further analyses will need to be conducted to determine whether these genotypes can be used as predictive markers for favorable therapeutic outcome. In this review, we discuss factors that affect response to mAb-based tumor therapies such as hu14.18-IL2. Many of our observations have been made in the context of NBL; however, we will also include some observations made with mAbs targeting other tumor types that are consistent with results in NBL. Therefore, we hypothesize that the NBL observations discussed here may also be relevant to mAb therapy for other cancers, in which ADCC is known to play a role.

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    • "Anti-TACA antibodies, thus, may be involved in more than direct tumor cytotoxicity even though this mechanism is exciting. Although, the exact mechanism may represent a cascade of steps that are still to be established, TACA targeting has the potential to yield anti-tumor effects mediated by Natural Killer cells, which has not been thoroughly investigated in humans even though there is some evidence of therapeutic benefit (118, 119) or through neutralization of tumor immunosuppressive factors in the form of soluble gangliosides (120–122). Future work should clarify the points of involvement of antibody/carbohydrate interactions in modulating tumor growth and facilitating innate surveillance mechanisms. "
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