Immune Response: A Missed Opportunity Between Vitamin D and Radiotherapy

Melatonin and vitamin D as potential synergistic adjuvants for cancer therapy (Review)

Significant advancements have been made in cancer therapy; however, limitations remain with some conventional approaches. Adjuvants are agents used alongside primary treatments to enhance their efficacy and the treatment outcomes of patients. Modern lifestyles contribute to deficiencies in melatonin and vitamin D. Limited sun exposure affects vitamin D synthesis, and artificial light at night suppresses melatonin production. Both melatonin and vitamin D possess anti‑inflammatory, immune‑boosting and anticancer properties, rendering them potential adjuvants of interest. Studies suggest melatonin and vitamin D supplementation may address antioxidant imbalances in lip, oral and pharyngeal cancers. Moreover, promising results from breast, head and neck, brain, and osteosarcoma research indicate potential for tumor growth inhibition, improved survival, and a better quality of life of patients with cancer. The radioprotective properties of melatonin and vitamin D are another exciting area of exploration, potentially enhancing radiotherapy effectiveness while reducing side effects. For its part, the sleep‑promoting effects of melatonin may indirectly benefit patients with cancer by influencing the immune system. Thus, the prevalence of vitamin D and melatonin deficiencies highlights the importance of supplementation, as lower levels can worsen side‑effects from cancer treatments. The present review explores the potential of combining melatonin and vitamin D as synergistic adjuvants for cancer therapy. These agents have shown promise individually in cancer prevention and treatment, and their combined effects warrant investigation. Therefore, large‑scale controlled trials are crucial to definitively determine the optimal dosage, safety and efficacy of this combination in improving the lives of patients with cancer.

Impact of chrono-radiotherapy on the prognosis and treatment-related toxicity in patients with locally advanced nasopharyngeal carcinoma: A multicenter propensity-matched study

The timing of radiotherapy (RT) delivery has been reported to affect both cancer survival and treatment toxicity. However, the association among the timing of RT delivery, survival, and toxicity in locally advanced nasopharyngeal carcinoma (LA-NPC) has not been investigated. We retrospectively reviewed patients diagnosed with LA-NPC who received definitive RT at multiple institutions. The median RT delivery daytime was categorized as morning (DAY) and night (NIGHT). Seasonal variations were classified into the darker half of the year (WINTER) and brighter half (SUMMER) according to the sunshine duration. Cohorts were balanced according to baseline characteristics using propensity score matching (PSM). Survival and toxicity outcomes were evaluated using Cox regression models. A total of 355 patients were included, with 194/161 in DAY/NIGHT and 187/168 in WINTER/SUMMER groups. RT delivered during the daytime prolonged the 5-year overall survival (OS) (90.6% vs. 80.0%, p = 0.009). However, the significance of the trend was lost after PSM (p = 0.068). After PSM analysis, the DAY cohort derived a greater benefit in 5-year progression-free survival (PFS) (85.6% vs. 73.4%, p = 0.021) and distant metastasis-free survival (DMFS) (89.2% vs. 80.8%, p = 0.051) in comparison with the NIGHT subgroup. Moreover, multivariate analysis showed that daytime RT was an independent prognostic factor for OS, PFS, and DMFS. Furthermore, daytime RT delivery was associated with an increase in the incidence of leukopenia and radiation dermatitis. RT delivery in SUMMER influenced only the OS significantly (before PSM: p = 0.051; after PSM: p = 0.034). There was no association between toxicity and the timing of RT delivery by season. In LA-NPC, the daytime of radical RT served as an independent prognostic factor. Furthermore, RT administered in the morning resulted in more severe toxic side effects than that at night, which needs to be confirmed in a future study.

Serum 25-Hydroxyvitamin D Is Inversely Associated with Nasopharyngeal Carcinoma: A Hospital-Based Matched Case-Control Study in Malaysia

Serum 25(OH)D deficiency consistently demonstrated molecular mechanisms through which chronic inflammation is associated with the risk of nasopharyngeal carcinoma (NPC). This study aimed to determine the association between serum 25(OH)D and NPC. A matched case-control study was conducted at two local hospitals. A total of 300 histologically confirmed NPC cases were matched with controls for age, gender, and ethnicity, and assessed for vitamin D status and other nutritional factors. Mean Vitamin D concentration was significantly lower among cases compared to controls (63.17 ± 19.15 nmol/L and 67.34 ± 23.06 nmol/L) (t = -2.41, p = 0.016). Multiple conditional logistic regression analysis indicated that higher levels of serum 25(OH)D were associated with reduced odds of NPC (AOR = 0.73, 95% CI = 0.57-0.94, p = 0.016) controlling for confounders including BMI, physical activity, smoking status, alcohol consumption, consumption of food high in vitamin D, salted fish consumption, and family history of NPC. There was a significant association between inadequate serum 25(OH)D status with accumulation of four risk factors and increased odds of getting NPC using polynomial regression analysis. Increased NPC odds ratios were observed after sequential accumulation of additional risk factors with the presence of inadequate serum 25(OH)D status (OR = 0.54, 95% CI = 0.27, 4.77, p = 0.322, OR = 1.04, 95% CI = 0.64, 1.72, p = 0.267, OR = 1.15, 95% CI = 0.73, 1.80, p = 0.067, OR = 1.93, 95% CI = 1.13, 3.31, p = 0.022, and OR = 5.55, 95% CI = 1.67, 10.3, p < 0.001 respectively). Future research in Malaysia should involve both prospective cohort studies and randomized controlled trials to confirm and further clarify the role of vitamin D in NPC outcomes.

Vitamin D can ameliorate premature ovarian failure by inhibiting neutrophil extracellular traps: A review

The etiology of premature ovarian failure (POF) is mainly related to inflammatory diseases, autoimmune diseases, and tumor radiotherapy and chemotherapy; however, its specific pathogenesis has not been clarified. Vitamin D (VD), a fat-soluble vitamin, is an essential steroid hormone in the human body. Neutrophil extracellular traps (NETs) are meshwork structures that are formed when neutrophils are stimulated by inflammation and other factors and are closely associated with autoimmune and inflammatory diseases. Notably, VD inhibits NET formation and intervenes in the development of POF in terms of inflammatory and immune responses, oxidative stress, and tissue fibrosis. Therefore, this study aimed to theorize the relationship between NETs, VD, and POF and provide new ideas and targets for the pathogenesis and clinical treatment of POF.