Vitamin D delivered through carbon quantum dots modifies cytokine expression and migration in MCF-7 breast cancer cells.

BACKGROUND

Vitamin D is a crucial regulator of immune responses and has recognized anti-proliferative effects in cancer. However, its clinical use is limited by poor solubility and bioavailability. Nanocarrier systems, such as carbon quantum dots (CQDs), may improve vitamin D delivery and activity.

METHODS

MCF-7 breast cancer cells were treated with free vitamin D or vitamin D-loaded CQDs (CQD-VitD). Cell viability was measured using the WST-8 assay; migration was assessed with a wound-healing assay; and gene expression of IL-6, IL-10, NF-κB, TNF-α, and VDR was analyzed through qRT-PCR.

RESULTS

CQD-VitD significantly increased cell viability compared to both control and free vitamin D (p < 0.01). Wound-healing assays demonstrated that CQD-VitD markedly inhibited cell migration, while free vitamin D caused moderate wound closure. Gene expression analysis showed that free vitamin D slightly decreased IL-6 and significantly suppressed IL-10 (p < 0.05). Conversely, CQD-VitD strongly upregulated IL-10 (p < 0.001) and NF-κB (p < 0.05), with TNF-α and VDR expression remaining unchanged.

CONCLUSION

CQD-based delivery of vitamin D enhances its cellular activity and selectively affects immune-related genes in breast cancer cells. Although CQD-VitD reduced migration and increased cell viability, its upregulation of IL-10 and NF-κB suggests a complex role in tumor-immune interactions. These findings highlight both the potential and the challenges of nanocarrier-mediated vitamin D delivery in breast cancer therapy. To our knowledge, this is the first study to investigate the effects of vitamin D-loaded carbon quantum dots on immune-related gene expression in breast cancer cells.