Modulation of Peripheral Immune Cells Following Vitamin D3 Supplementation in Vitamin D-Insufficient Cancer Patients.

DNA integrity in mononuclear cells improved significantly after vitamin D3 supplementation and serum 25-hydroxy-vitamin D level normalization.

• Eight cancer patients (5 lung cancer, 2 colorectal cancer, 1 urothelial carcinoma) received 30,000 IU of vitamin D3 per week for two months.
• DNA integrity improvement in mononuclear cells was statistically significant (p = 0.01).
• No significant changes in DNA integrity were found in granulocytes.
• DNA integrity was assessed using the alkaline Comet-assay.

Vitamin D3 supplementation led to significant changes in telomere length in mononuclear cells.

• Telomere length change in mononuclear cells reached statistical significance (p = 0.007).
• Telomere length was assessed by telomere qPCR.
• The study included eight patients under active oncological treatment.
• Blood samples were collected before and after the two-month supplementation period.

No significant differences were observed in cfDNA levels or DNA methylation in PBMCs and cfDNA after vitamin D3 supplementation.

• Global DNA methylation level was estimated based on LINE-1 bisulfite-sequencing experiments on cfDNA and PBMC cells.
• Neither circulating cell-free DNA (cfDNA) levels nor DNA methylation showed significant changes post-supplementation.
• DNA methylation was assessed in both PBMC cells and cfDNA compartments.

ATAC-Seq revealed changes in PBMC composition, including an increased number of NK cells, plasmacytoid dendritic cells (pDC), and monocytes following vitamin D3 supplementation.

• Chromatin accessibility alterations were explored using ATAC-Seq performed with 10x Genomics on a NextSeq 550 instrument using the High Output Sequencing kit (Illumina).
• Increased NK cells, pDC cells, and monocytes were observed in PBMC composition after supplementation.
• These immune cell changes were especially pronounced in patients treated with Pembrolizumab in parallel with vitamin D supplementation.
• ATAC-Seq was used to infer PBMC cell composition changes based on chromatin accessibility profiles.

The study enrolled eight cancer patients with vitamin D insufficiency receiving 30,000 IU of vitamin D3 per week for two months alongside ongoing oncological treatment.

• Patient diagnoses included 5 lung cancer, 2 colorectal cancer, and 1 urothelial carcinoma.
• The supplementation dose was 30,000 IU of vitamin D3 per week for a duration of two months.
• PBMCs were isolated from blood samples collected before and after supplementation.
• Multiple assays were employed: alkaline Comet-assay, telomere qPCR, LINE-1 bisulfite sequencing, and ATAC-Seq.

The authors conclude that observed immune cell and chromatin changes after vitamin D3 level normalization are compatible with immunomodulatory effects but require confirmation in larger, controlled cohorts.

• The study is described as exploratory in nature.
• Findings include changes in PBMC composition, DNA integrity, and telomere length.
• Authors note the findings 'warrant confirmation in larger, controlled cohorts.'
• The small sample size of eight patients is an acknowledged limitation of the study.