Vitamin D Modifies the Incidence of Graft-versus-Host Disease after Allogeneic Stem Cell Transplantation Depending on the Vitamin D Receptor (VDR) Polymorphisms.

PURPOSE: The biologically active metabolite of vitamin D3, 1,25-dihydroxyvitamin D3 (vit D), has immunoregulatory properties via binding vitamin D receptor (VDR). In a prospective trial, we previously reported a reduction in the incidence of chronic GvHD (cGvHD) among patients who received vit D after allogeneic stem cell transplantation (allo-HSCT; Clinical Trials.gov: NCT02600988). Here we analyze the role of patients and donors' VDR SNPs on the immunomodulatory effect of vit D. PATIENTS AND METHODS: Patients undergoing allo-HSCT were included in a prospective phase I/II clinical trial (Alovita) in three consecutive cohorts: control (without vit D), low-dose (1,000 IU/day), and high-dose (5,000 IU/day) groups. Vit D was given from day -5 until +100 after transplant. Genotyping of four SNPs of the VDR gene, FokI, BsmI, ApaI, and TaqI, were performed using TaqMan SNP genotyping assays. RESULTS: We observed a decrease in the incidence of overall cGvHD at 1 year after allo-HSCT depending on the use or not of vit D among patients with FokI CT genotype (22.5% vs 80%, P = 0.0004) and among those patients without BsmI/ApaI/TaqI ATC haplotype (22.2% vs 68.8%, P = 0.0005). In a multivariate analysis, FokI CT genotype significantly influenced the risk of cGvHD in patients treated with vit D as compared with the control group (HR 0.143, P interaction < 0.001). CONCLUSIONS: Our results show that the immunomodulatory effect of vit D depends on the VDR SNPs, and patients carrying the FokI CT genotype display the highest benefit from receiving vit D after allo-HSCT.

Immunomodulatory Effect of Vitamin D after Allogeneic Stem Cell Transplantation: Results of a Prospective Multicenter Clinical Trial.

PURPOSE: We describe the results of a prospective multicenter phase I/II trial evaluating the impact of the use of vitamin D (VitD) from day -5 to +100 on the outcome of patients undergoing allogeneic transplantation (EudraCT: 2010-023279-25; ClinicalTrials.gov: NCT02600988). EXPERIMENTAL DESIGN: A total of 150 patients were included in three consecutive cohorts of 50 patients each group: control group (CG, not receive VitD); low-dose group (LdD, received 1,000 IU VitD daily); and high-dose group (HdD, 5,000 IU VitD daily). We measured levels of VitD, cytokines, and immune subpopulations after transplantation. RESULTS: No significant differences were observed in terms of cumulative incidence of overall and grades 2-4 acute GVHD in terms of relapse, nonrelapse mortality, and overall survival. However, a significantly lower cumulative incidence of both overall and moderate plus severe chronic GVHD (cGVHD) at 1 year was observed in LdD (37.5% and 19.5%, respectively) and HdD (42.4% and 27%, respectively) as compared with CG (67.5% and 44.7%, respectively; P < 0.05). In multivariable analysis, treatment with VitD significantly decreased the risk of both overall (for LdD: HR = 0.31, P = 0.002; for HdD: HR = 0.36, P = 0.006) and moderate plus severe cGVHD (for LdD: HR = 0.22, P = 0.001; for HdD: HR = 0.33, P = 0.01). VitD modified the immune response, decreasing the number of B cells and naïve CD8 T cells, with a lower expression of CD40L. CONCLUSIONS: This is the first prospective trial that analyzes the effect of VitD postransplant. We observed a significantly lower incidence of cGVHD among patients receiving VitD. Interestingly, VitD modified the immune response after allo-SCT. Clin Cancer Res; 22(23); 5673-81. ©2016 AACR.