Vitamin D Deficiency has a Negative Impact on Cetuximab-Mediated Cellular Cytotoxicity against Human Colon Carcinoma Cells.

BACKGROUND: Hypovitaminosis D is associated with an adverse prognosis in colon cancer patients, possibly due to the effects of the vitamin on the immune system. Antibody-dependent cell-mediated cytotoxicity (ADCC) significantly contributes to the anti-tumor effects of monoclonal antibodies, including cetuximab, an epidermal growth factor receptor (EGFR)-targeted monoclonal antibody that is frequently added to chemotherapy in the treatment of colon cancer. OBJECTIVE: The present study evaluates the association between vitamin D serum levels and the ability of ex vivo NK cells to support cetuximab-mediated ADCC in colon cancer cell lines. METHODS: Blood samples were obtained from 124 healthy volunteers and serum vitamin D was determined by RIA. NK cells were isolated from each sample and added to human colorectal carcinoma cells with or without cetuximab, and ADCC was assessed using a colorimetric lactate dehydrogenase assay. RESULTS: Correlation analysis indicates a significant, gender- and age-independent association between vitamin D levels and cetuximab-induced ADCC on HT29 cells, where NK cells from samples with vitamin D < 20 ng/mL are significantly less efficient in inducing ADCC. A confirmatory study on two additional colon cancer cell lines yielded similar results. CONCLUSIONS: These data suggest that vitamin D supplementation in vitamin-deficient/insufficient colorectal cancer patients could improve cetuximab-induced ADCC.

Goals and objectives of the Italian Network for Tumor Biotherapy (NIBIT).

The explosion in the immuno-oncology field, exemplified by the clinical implementation of immune checkpoint inhibitor blockade and other immunotherapeutic strategies was quickly recognized by the Italian biomedical community, thanks to the networking activities of the Italian Network for Tumor Biotherapy (NIBIT), which has been active since 2004 in the diffusion of new scientific and clinical findings in the fields of tumor immunology and immunotherapy. Numerous activities of NIBIT have also helped to overcome the hurdles associated with the clinical implementation of cancer immune-biotherapeutic strategies at the national and international levels. Looking forward, a concerted interaction of NIBIT with existing European networks focused on cancer bio-immunotherapy will further contribute to the development of improved therapies in the immuno-oncology field. This Introduction briefly summarizes the history and objectives of NIBIT, as well as the current activities of the Network.