Newly-identified Pathways Relating Vitamin D to Carcinogenesis: A Review

Post-diagnosis serum 25-hydroxyvitamin D concentrations in women treated for breast cancer participating in a lifestyle trial in Italy

OBJECTIVE

To report cross-sectionally serum levels of 25-hydroxyvitamin D [25(OH)D] in women living in Italy within 12 months from breast cancer (BC) diagnosis.

METHODS

Baseline data were obtained from 394 women diagnosed with primary BC, enrolled from 2016 to 2019 in a lifestyle trial conducted in Italy. Subjects' characteristics were compared between two 25(OH)D concentrations (hypovitaminosis D<20 and ≥20 ng/mL) with the Chi-squared test or Fisher's exact test for small-expected counts. Using multiple logistic regression-adjusted models, we estimated odds ratios (ORs) of hypovitaminosis D with 95% confidence intervals (CIs) in the total sample and in the unsupplemented subgroup.

RESULTS

Hypovitaminosis D was found in 39% of all subjects, 60% in unsupplemented subjects, and 10% in supplemented subjects. Increasing ORs of hypovitaminosis D were found with increasing body mass index, 25-30, >30, and ≥35 versus <25 kg/m2 (ORs: 2.50, 4.64, and 5.81, respectively, in the total cohort and ORs: 2.68, 5.38, and 7.08 in the unsupplemented); living in the most southern Italian region (OR 2.50, 95%CI 1.22-5.13); and with hypertriglyceridemia (OR 2.46; 95%CI 1.16-5.22), chemotherapy history (OR 1.86, 95%CI 1.03-3.38), and inversely with anti-estrogenic therapy (OR 0.43, 95%CI 0.24-0.75) in the total sample.

CONCLUSIONS

Hypovitaminosis D in women recently diagnosed with BC and participating in a lifestyle trial in Italy was widespread and highest with obesity, hypertriglyceridemia, and chemotherapy use. Considering that hypovitaminosis D is a risk factor for lower efficacy of bone density treatments and possibly BC mortality, our results suggest the need to promptly address and treat vitamin D deficiency.

Potential tactics with vitamin D and certain phytochemicals for enhancing the effectiveness of immune-checkpoint blockade therapies

Immunotherapy strategies targeting immune checkpoint molecules such as programmed cell death-1 (PD-1) and cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) are revolutionizing oncology. However, its effectiveness is limited in part due to the loss of effector cytotoxic T lymphocytes. Interestingly, supplementation of vitamin D could abolish the repressive effect of programmed cell death-ligand 1 (PD-L1) on CD8⁺ T cells, which might prevent the lymphocytopenia. In addition, vitamin D signaling could contribute to the differentiation of T-regulatory (Treg) cells associated with the expression of Treg markers such as forkhead box P3 (FOXP3) and CTLA-4. Furthermore, vitamin D may be associated with the stimulation of innate immunity. Peroxisome proliferator-activated receptor (PPAR) and estrogen receptor (ESR) signaling, and even the signaling from phosphoinositide-3 kinase (PI3K)/AKT pathway could have inhibitory roles in carcinogenesis possibly via the modulation of immune checkpoint molecules. In some cases, certain small molecules including vitamin D could be a novel therapeutic modality with a promising potential for the better performance of immune checkpoint blockade cancer therapies.

Regular use of vitamin D supplement is associated with fewer melanoma cases compared to non-use: a cross-sectional study in 498 adult subjects at risk of skin cancers

There are conflicting results on the role of vitamin D system in cutaneous carcinogenesis. Therefore, it was investigated whether the use of oral vitamin D supplements associates with photoaging, actinic keratoses, pigment cell nevi, and skin cancers. In this cross-sectional study, 498 adults (aged 21-79 years, 253 males, 245 females, 96 with immunosuppression) subjects at risk of any type of skin cancer were examined, and possible confounding factors were evaluated. The subjects were divided into three groups based on their self-reported use of oral vitamin D supplements: non-use, occasional use, or regular use. The serum level of 25-hydroxyvitamin-D3 was analyzed in 260 subjects. In 402 immunocompetent subjects, vitamin D use did not associate with photoaging, actinic keratoses, nevi, basal, and squamous cell carcinoma. In contrast, there were lower percentages of subjects with a history of past or present melanoma (32/177, 18.1% versus 32/99, 32.3%, P  = 0.021) or any type of skin cancer (110/177, 62.1% versus 74/99, 74.7%, P  = 0.027) among regular users compared to non-users. In the logistic regression analysis, the odds ratio for melanoma was 0.447 ( P  = 0.016, 95% confidence interval, 0.231-0.862) among regular users. Furthermore, the investigator-estimated risk class of skin cancers was significantly lower among regular users. Serum 25-hydroxyvitamin-D3 did not show marked associations with skin-related parameters. The results on 96 immunosuppressed subjects were somewhat similar, although the number of subjects was low. In conclusion, regular use of vitamin D associates with fewer melanoma cases, when compared to non-use, but the causality between them is obscure.

Vitamin D3 Supplementation Promotes Regulatory T-Cells to Maintain Immune Homeostasis After Surgery for Early Stages of Colorectal Cancer

BACKGROUND/AIM

Vitamin D₃ (VD₃) affects the regulation of the immune system, including the differentiation and function of regulatory T-cells (Tregs). Tregs play an important role in maintaining immune homeostasis in patients with colorectal cancer (CRC). The effects of VD₃ on Treg-associated immune function were investigated in Thai patients in the early stages of CRC.

MATERIALS AND METHODS

Twenty-eight patients were randomized to one of two groups: Untreated or treatment with VD₃ for 3 months. Whole blood samples were collected at baseline, and at 1 and 3 months. Peripheral blood mononuclear cells were isolated and the populations of forkhead box P3-positive Treg cells was analyzed by flow cytometry. The levels of Treg-associated cytokines, interleukin 10 (IL-10) and transforming growth factor beta 1 (TGF-β1), were measured by enzyme-linked immunosorbent assays.

RESULTS

Serum VD₃ levels of the VD₃-treated group were significantly increased at 1 (p=0.017) and 3 months (p<0.001) compared to the untreated control group. The mean percentage of Tregs was maintained between 1 and 3 months in the VD₃-treated group. At 3 months, the untreated group had significantly lower Treg levels than the VD₃-treated group (p=0.043). Serum IL-10 levels of the VD₃-treated group were statistically increased at 1 month compared to the control group (p=0.032). No significant difference in serum TGF-β1 levels was observed between the two groups. However, the TGF-β1 level in the VD₃-treated group at 1 month was lower than that of the control.

CONCLUSION

Our findings suggest that VD₃ supplementation can maintain immune responses in the early stages of CRC, helping to control Treg function. Therefore, VD₃ should be supplemented to maintain immune homeostasis, especially in patients with vitamin D deficiency.

Effects of Vitamin D3 Supplementation on Cardiovascular and Cancer Outcomes by eGFR in VITAL

Background

Reduced 25-hydroxyvitamin D (25[OH]D) metabolism and secondary hyperparathyroidism are common with lower estimated glomerular filtration rate (eGFR) and may contribute to cardiovascular disease and cancer risk.

Methods

We assessed for heterogeneity by baseline eGFR of the effects of vitamin D3 on cardiovascular and cancer outcomes in the Vitamin D and Omega-3 Trial (VITAL). Participants were randomized to 2000 IU vitamin D3 and/or 1 g Ω-3 fatty acids daily using a placebo-controlled, two-by-two factorial design (5.3 years follow-up). Primary study end points were incident major cardiovascular events and invasive cancer. Changes in serum 25(OH)D and parathyroid hormone (PTH) were examined.

Results

Baseline eGFR was available for 15,917 participants. Participants' mean age was 68 years, and 51% were women. Vitamin D3 resulted in higher serum 25(OH)D compared with placebo (difference in change 12.5 ng/ml; 95% CI, 12 to 13.1 ng/ml), without heterogeneity by eGFR (P interaction, continuous eGFR=0.2). Difference in change in PTH between vitamin D3 and placebo was larger with lower eGFR (P interaction=0.05): -6.9 (95% CI, -10.5 to -3.4), -5.8 (95% CI, -8.3 to -3.4), -4 (95% CI, -5.9 to -2.2), and -3.8 (95% CI, -5.6 to -2) pg/ml for eGFR <60, 60-74, 75-89, and ≥90 ml/min per 1.73 m2, respectively. Effects of vitamin D3 supplementation on cardiovascular events (P interaction=0.61) and cancer (P interaction=0.89) did not differ by eGFR: HR=1.14 (95% CI, 0.73 to 1.79), HR=1.06 (95% CI, 0.75 to 1.5), HR=0.92 (95% CI, 0.67 to 1.25), and HR=0.92 (95% CI, 0.66 to 1.27) across eGFR categories for cardiovascular events and HR=1.63 (95% CI, 1.03 to 2.58), HR=0.85 (95% CI, 0.64 to 1.11), HR=0.84 (95% CI, 0.68 to 1.03), and 1.11 (95% CI, 0.92 to 1.35) for cancer, respectively.

Conclusions

We observed no significant heterogeneity by baseline eGFR in the effects of vitamin D3 supplementation versus placebo on cardiovascular or cancer outcomes, despite effects on 25(OH)D and PTH concentrations.

Vitamin D Metabolites in Nonmetastatic High-Risk Prostate Cancer Patients with and without Zoledronic Acid Treatment after Prostatectomy

Simple Summary

Recent research on prostate cancer and vitamin D is controversial. We measured three vitamin D₃ metabolites in 32 selected prostate cancer patients after surgery at four time points over four years. Within a large European study, half of the patients were prophylactically treated with zoledronic acid (ZA); the others received a placebo. After the study start, all the patients daily took calcium and vitamin D₃. The development of metastasis was not affected by ZA treatment. While two vitamin D metabolites had higher values after the study’s start, with constant follow-up values, the 1,25(OH)₂-vitamin D₃ concentrations remained unchanged. The latter form was the only metabolite that was higher in the patients with metastasis as compared to those without bone metastasis. This result is surprising. However, it is too premature to discuss possible prognostic value yet. Our results should be confirmed in larger cohorts.

Abstract

There are limited and discrepant data on prostate cancer (PCa) and vitamin D. We investigated changes in three vitamin D₃ metabolites in PCa patients after prostatectomy with zoledronic acid (ZA) treatment regarding their metastasis statuses over four years. In 32 patients from the ZEUS trial, 25(OH)D₃, 24,25(OH)₂D₃, and 1,25(OH)₂D₃ were measured with liquid chromatography coupled with tandem mass spectrometry at four time points. All the patients received daily calcium and vitamin D₃. Bone metastases were detected in 7 of the 17 ZA-treated patients and in 5 of the 15 controls (without ZA), without differences between the groups (p = 0.725). While 25(OH)D₃ and 24,25(OH)₂D₃ increased significantly after the study’s start, with following constant values, the 1,25(OH)₂D₃ concentrations remained unchanged. ZA treatment did not change the levels of the three metabolites. 25(OH)D₃ and 24,25(OH)₂D₃ were not associated with the development of bone metastases. In contrast, 1,25(OH)₂D₃ was also higher in patients with bone metastasis before the study’s start. Thus, in high-risk PCa patients after prostatectomy, 25(OH)D₃, 24,25(OH)₂D₃, and 1,25(OH)₂D₃ were not affected by supportive ZA treatment or by the development of metastasis over four years, with the exception of 1,25(OH)₂D₃, which was constantly higher in metastatic patients. There might be potential prognostic value if the results can be confirmed.

Combinations of Calcitriol with Anticancer Treatments for Breast Cancer: An Update

Preclinical, clinical, and epidemiological studies indicate that vitamin D3 (VD) deficiency is a risk factor for the development of breast cancer. Underlying mechanisms include the ability of calcitriol to induce cell differentiation, inhibit oncogenes expression, and modify different signaling pathways involved in the control of cell proliferation. In addition, calcitriol combined with different kinds of antineoplastic drugs has been demonstrated to enhance their beneficial effects in an additive or synergistic fashion. However, a recognized adjuvant regimen based on calcitriol for treating patients with breast cancer has not yet been fully established. Accordingly, in the present work, we review and discuss the preclinical and clinical studies about the combination of calcitriol with different oncological drugs, aiming to emphasize its main therapeutic benefits and opportunities for the treatment of this pathology.

Identifying a possible new target for diagnosis and treatment of postmenopausal osteoporosis through bioinformatics and clinical sample analysis

Background

Postmenopausal osteoporosis, a common yet chronic systemic metabolic disease, has become a major public health problem due to life expectancy increasing around the world. The differentiation of mesenchymal stem cells (MSCs) into osteoblasts, and the differentiation of circulating monocyte cells into osteoclasts, play an important role in the balance of bone metabolism. However, when both undergo pathological changes, it can lead to abnormalities, resulting in osteoporosis. This study aims to explore a new biomarker for postmenopausal osteoporosis, thereby providing a new entry point for bioinformatic research into the clinical diagnosis and treatment of the disease.

Methods

Using the Gene Expression Omnibus (GEO) database, microarray analysis was conducted to identify differentially expressed genes in MSCs and monocytes in both postmenopausal osteoporosis patients and a healthy control group. The Database for Annotation, Visualization and Integrated Discovery (DAVID) database was used to analyze the function and enrichment of the selected genes, and a protein-protein interaction (PPI) network was constructed from the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) website and displayed in Cytoscape. To achieve the final results, module analysis of the PPI network was performed by using Molecular Complex Detection (MCODE).

Results

We identified 45 high-expression and 26 low-expression genes through the study, all of which underwent pathway enrichment analysis. This enrichment was observed in the cell cycle regulation, osteoclast differentiation, tumor necrosis factor (TNF) signaling pathway, and RNA transport. The top 10 hub genes of the PPI network were SF3B1, SRSF5, FUBP1, SRSF3, TIA1, KHSRP, LUC7L3, PNN, SRC, and ATRX. Comparing the MSCs and monocytes between the postmenopausal osteoporosis patients and the healthy control group, we noted that the expression of the above genes differed greatly.

Conclusions

Through bioinformatic analysis and clinical specimen validation, our study provides a new way for exploring the pathogenesis of postmenopausal osteoporosis. Most importantly, it suggests that the hub genes, SF3B1, SRSF5, FUBP1, KHSRP, and SRC, may become new diagnostic markers and therapeutic targets for diagnosing and treating postmenopausal osteoporosis in the future.