c-Jun NH2-teminal kinase 1 interacts with vitamin D receptor and affects vitamin D-mediated inhibition of cancer cell proliferation

VDR is a potential prognostic biomarker and positively correlated with immune infiltration: a comprehensive pan-cancer analysis with experimental verification

The vitamin D receptor (VDR) is a transcription factor that mediates a variety of biological functions of 1,25-dihydroxyvitamin D3. Although there is growing evidence of cytological and animal studies supporting the suppressive role of VDR in cancers, the conclusion is still controversial in human cancers and no systematic pan-cancer analysis of VDR is available. We explored the relationships between VDR expression and prognosis, immune infiltration, tumor microenvironment, or gene set enrichment analysis (GSEA) in 33 types of human cancers based on multiple public databases and R software. Meanwhile, the expression and role of VDR were experimentally validated in papillary thyroid cancer (PTC). VDR expression decreased in 8 types and increased in 12 types of cancer compared with normal tissues. Increased expression of VDR was associated with either good or poor prognosis in 13 cancer types. VDR expression was positively correlated with the infiltration of cancer-associated fibroblasts, macrophages, or neutrophils in 20, 12, and 10 cancer types respectively and this correlation was experimentally validated in PTC. Increased VDR expression was associated with increased percentage of stromal or immune components in tumor microenvironment (TME) in 24 cancer types. VDR positively and negatively correlated genes were enriched in immune cell function and energy metabolism pathways, respectively, in the top 9 highly lethal tumors. Additionally, VDR expression was increased in PTC and inhibited cell proliferation and migration. In conclusion, VDR is a potential prognostic biomarker and positively correlated with immune infiltration as well as stromal or immune components in TME in multiple human cancers.

Role of vitamins A, C, D, E in cancer prevention and therapy: therapeutic potentials and mechanisms of action

Cancer, a leading global cause of mortality, arises from intricate interactions between genetic and environmental factors, fueling uncontrolled cell growth. Amidst existing treatment limitations, vitamins have emerged as promising candidates for cancer prevention and treatment. This review focuses on Vitamins A, C, E, and D because of their protective activity against various types of cancer. They are essential as human metabolic coenzymes. Through a critical exploration of preclinical and clinical studies via PubMed and Google Scholar, the impact of these vitamins on cancer therapy was analyzed, unraveling their complicated mechanisms of action. Interestingly, vitamins impact immune function, antioxidant defense, inflammation, and epigenetic regulation, potentially enhancing outcomes by influencing cell behavior and countering stress and DNA damage. Encouraging clinical trial results have been observed; however, further well-controlled studies are imperative to validate their effectiveness, determine optimal dosages, and formulate comprehensive cancer prevention and treatment strategies. Personalized supplementation strategies, informed by medical expertise, are pivotal for optimal outcomes in both clinical and preclinical contexts. Nevertheless, conclusive evidence regarding the efficacy of vitamins in cancer prevention and treatment is still pending, urging further research and exploration in this compelling area of study.

Hedgehog signaling in gastrointestinal carcinogenesis and the gastrointestinal tumor microenvironment

The Hedgehog (HH) signaling pathway plays important roles in gastrointestinal carcinogenesis and the gastrointestinal tumor microenvironment (TME). Aberrant HH signaling activation may accelerate the growth of gastrointestinal tumors and lead to tumor immune tolerance and drug resistance. The interaction between HH signaling and the TME is intimately involved in these processes, for example, tumor growth, tumor immune tolerance, inflammation, and drug resistance. Evidence indicates that inflammatory factors in the TME, such as interleukin 6 (IL-6) and interferon-γ (IFN-γ), macrophages, and T cell-dependent immune responses, play a vital role in tumor growth by affecting the HH signaling pathway. Moreover, inhibition of proliferating cancer-associated fibroblasts (CAFs) and inflammatory factors can normalize the TME by suppressing HH signaling. Furthermore, aberrant HH signaling activation is favorable to both the proliferation of cancer stem cells (CSCs) and the drug resistance of gastrointestinal tumors. This review discusses the current understanding of the role and mechanism of aberrant HH signaling activation in gastrointestinal carcinogenesis, the gastrointestinal TME, tumor immune tolerance and drug resistance and highlights the underlying therapeutic opportunities.

Pirfenidone and Vitamin D Ameliorate Cardiac Fibrosis Induced by Doxorubicin in Ehrlich Ascites Carcinoma Bearing Mice: Modulation of Monocyte Chemoattractant Protein-1 and Jun N-terminal Kinase-1 Pathways

Treatment of breast cancer with doxorubicin causes numerous side effects, of which cardiac fibrosis is considered the main one. This study was designed to investigate the underlying molecular mechanisms for the potential anti-fibrotic effect of pirfenidone and vitamin D against doxorubicin-induced cardiac fibrosis. Seventy mice carrying solid Ehrlich’s ascites carcinoma (EAC) discs on the ventral side were treated with orally administered pirfenidone (500 mg/kg) and intraperitoneal injection of vitamin D (0.5 µg/kg) either individually or in combination with a doxorubicin (15 mg/kg; i.p.) single dose. All treatments commenced one week post-tumor inoculation and continued for 14 days. Compared to control EAC mice, the doxorubicin group showed a significant increase in heart and left ventricle weights, troponin T, and creatinine kinase serum levels. Furthermore, the doxorubicin group depicts a high expression of monocyte chemoattractant protein (MCP-1), nuclear factor-kappa B (NF-κB), transforming growth factor-beta 1 (TGF-β1), smad3, Jun N-terminal Kinase-1 (JNK1), and alpha-smooth muscle actin (α-SMA). Treatment with pirfenidone or vitamin D significantly decreased all of these parameters. Furthermore, the expression of smad7 was downregulated by doxorubicin and improved by pirfenidone or vitamin D. Furthermore, all treated groups showed a marked decrease in tumor weight and volume. Current data demonstrate that pirfenidone and vitamin D represent an attractive approach to ameliorate the cardiac fibrosis produced by doxorubicin through inhibiting both JNK1 signaling and MCP-1 inflammatory pathways, thus preserving heart function. Further, this combination demonstrated an anti-tumor effect to combat breast cancer.

The vitamin D receptor Taq I polymorphism is associated with reduced VDR and increased PDIA3 protein levels in human intestinal fibroblasts

The synonymous single nucleotide polymorphism (SNP) rs731236, located in the vitamin D receptor (VDR) gene (Taq I) has been associated with both decreased levels of the protein in peripheral blood mononuclear cells and a fibrosis-related complication in Crohn´s disease (CD). Interactions between VDR and a protein-disulfide isomerase-associated 3 (PDIA3) in the regulation of extracellular matrix have been reported and we aim to analyze the relevance of the VDR genotypes and the effects of Vitamin D (VD) in the expression of VDR, PDIA3 and proliferation of intestinal fibroblasts. Human intestinal fibroblasts were isolated from the non-affected surgical resections of colorectal patients and classified according to the VDR genotype. In some cases, cells were transfected with specific PDIA3 siRNA. Basal and VD-stimulated expression of VDR, PDIA3 and Collagen 1A1 (COL1A1) as well as fibroblast migration/proliferation were analyzed. Our data show that intestinal fibroblasts homozygous for the C allele in the VDR gene exhibited lower VDR protein levels and higher proliferation than cells homozygous for the T allele. VD increased VDR and attenuated the accelerated proliferation of CC fibroblasts. The diminished VDR level detected in CC cells was associated with increased levels of both PDIA3 and COL1A1 expression and the transient silencing of PDIA3 significantly reduced COL1A1 expression. We conclude that intestinal fibroblasts homozygous for the C allele in the VDR gene exhibited: reduced VDR protein levels, increased proliferation and increased PDIA3/COL1A1 expression. Treatment with VD increased VDR and attenuated proliferation of these cells.

Vitamin D-Induced Molecular Mechanisms to Potentiate Cancer Therapy and to Reverse Drug-Resistance in Cancer Cells

Increasing interest in studying the role of vitamin D in cancer has been provided by the scientific literature during the last years, although mixed results have been reported. Vitamin D deficiency has been largely associated with various types of solid and non-solid human cancers, and the almost ubiquitous expression of vitamin D receptor (VDR) has always led to suppose a crucial role of vitamin D in cancer. However, the association between vitamin D levels and the risk of solid cancers, such as colorectal, prostate and breast cancer, shows several conflicting results that raise questions about the use of vitamin D supplements in cancer patients. Moreover, studies on vitamin D supplementation do not always show improvements in tumor progression and mortality risk, particularly for prostate and breast cancer. Conversely, several molecular studies are in agreement about the role of vitamin D in inhibiting tumor cell proliferation, growth and invasiveness, cell cycle arrest and inflammatory signaling, through which vitamin D may also regulate cancer microenvironment through the activation of different molecular pathways. More recently, a role in the regulation of cancer stem cells proliferation and short non-coding microRNA (miRNAs) expression has emerged, conferring to vitamin D a more crucial role in cancer development and progression. Interestingly, it has been shown that vitamin D is able not only to potentiate the effects of traditional cancer therapy but can even contribute to overcome the molecular mechanisms of drug resistance—often triggering tumor-spreading. At this regard, vitamin D can act at various levels through the regulation of growth of cancer stem cells and the epithelial–mesenchymal transition (EMT), as well as through the modulation of miRNA gene expression. The current review reconsiders epidemiological and molecular literature concerning the role of vitamin D in cancer risk and tumor development and progression, as well as the action of vitamin D supplementation in potentiating the effects of drug therapy and overcoming the mechanisms of resistance often triggered during cancer therapies, by critically addressing strengths and weaknesses of available data from 2010 to 2020.

The correlation between low vitamin D status and renal interleukin-6/STAT3 hyper-activation in patients with clear cell renal cell carcinoma

Low vitamin D status has been associated with increased risks of renal cell carcinoma (RCC). This study aimed to analyze the link between low vitamin D status and interleukin (IL)-6/STAT3 hyper-activation in clear cell RCC (ccRCC) patients. Forty-three newly diagnosed ccRCC patients and 86 age- and sex-matched controls were recruited. The association between low vitamin D status and IL-6/STAT3 hyper-activation was analyzed. Proliferation makersand STAT3 signal were evaluated. As expected, serum IL-6 level was higher in ccRCC patients than in controls. Moreover, serum IL-6 level was reversely correlated with serum 25(OH)D in ccRCC patients but not in controls. In addition, STAT3 signaling was hyper-activated in cancerous tissue. CcRCC patients were divided into three groups according to serum 25(OH)D level: vitamin D sufficiency (VitD-S, ≥30 ng/ml), vitamin D insufficiency (VitD-I, ≥20 and <30 ng/ml) or vitamin D deficiency (VitD-D, <20 ng/ml). Serum IL-6 was higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. Cancerous pSTAT3 level was higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The number of pSTAT3⁺ nuclei in cancerous tissue was more in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The expressions of cancerous PCNA, cyclin D1 and Ki-67, three markers of proliferation, were higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The in vitro experiments showed that active vitamin D3 inhibited LPS-induced STAT3 phosphorylation in ACHN cells. Our results provide evidence that low vitamin D status is correlated with hyper-activation of cancerous IL-6/STAT3 and proliferation in ccRCC patients.

Fine tuning of vitamin D receptor (VDR) activity by post-transcriptional and post-translational modifications

Vitamin D receptor (VDR) is a member of the nuclear receptor (NR) superfamily of ligand-activated transcription factors. Activated VDR is responsible for maintaining calcium and phosphate homeostasis, and is required for proper cellular growth, cell differentiation and apoptosis. The expression of both phases I and II drug-metabolizing enzymes is also regulated by VDR, therefore it is clinically important.

Post-translational modifications of NRs have been known as an important mechanism modulating the activity of NRs and their ability to drive the expression of target genes. The aim of this mini review is to summarize the current knowledge about post-transcriptional and post-translational modifications of VDR.

Yin-yang regulating effects of cancer-associated genes, proteins, and cells: An ancient Chinese concept in vogue in modern cancer research

Great achievements have been made in human cancer research, but most of this research is focused on conditions at the microscopic rather than the systemic level. Recent studies have increasingly cited the ancient Chinese theory of yin-yang in an effort to expand beyond the microscopic level. Various cancer-associated genes and proteins such as mitogen-activated protein kinase (MAPK), p38, p53, c-Myc, tumor necrosis factor (TNF)-α, NF-κB, Cyclin D1, and cyclin-dependent kinase (CDK) and cells such as T cells, B cells, macrophages, neutrophils, and fibroblasts have been reported to regulate various types of cancers in a yin-yang manner. These studies have brought the theory of yin-yang into vogue in cancer research worldwide.

1α,25-Dihydroxyvitamin D3 up-regulates IL-34 expression in SH-SY5Y neural cells

Vitamin D supplementation is regarded as a novel approach to treat Alzheimer’s disease, but the underlying mechanism remains elusive. The cytokine IL-34 provides strong neuroprotective and survival signals in brain injury and neurodegeneration and could be an immunological mediator for the vitamin D-induced protection. The aim of this study was to investigate whether human IL-34 is up-regulated in neuronal cells by the hormonally active form of vitamin D, 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3]. We found that IL-34 was detectable in a variety of cell lines and its expression was strongly induced in SH-SY5Y neural cells in a dose- and time-dependent manner by 1α,25(OH)2D3 through the vitamin D receptor (VDR). Furthermore, we identified the core promoter of IL-34 gene and a VDR binding site (CGCCCT) that was required for 1α,25(OH)2D3-induced IL-34 expression. These findings suggest that the induction of IL-34 expression by 1α,25(OH)2D3 may constitute a mechanism that explains the protective function of vitamin D in Alzheimer’s disease.

Crosstalk between sphingolipids and vitamin D3: potential role in the nervous system

Sphingolipids are both structural and bioactive compounds. In particular, ceramide and sphingosine 1-phosphate regulate cell fate, inflammation and excitability. 1-α,25-dihydroxyvitamin D3 (1,25(OH)2 D3 ) is known to play an important physiological role in growth and differentiation in a variety of cell types, including neural cells, through genomic actions mediated by its specific receptor, and non-genomic effects that result in the activation of specific signalling pathways. 1,25(OH)2 D3 and sphingolipids, in particular sphingosine 1-phosphate, share many common effectors, including calcium regulation, growth factors and inflammatory cytokines, but it is still not known whether they can act synergistically. Alterations in the signalling and concentrations of sphingolipids and 1,25(OH)2 D3 have been found in neurodegenerative diseases and fingolimod, a structural analogue of sphingosine, has been approved for the treatment of multiple sclerosis. This review, after a brief description of the role of sphingolipids and 1,25(OH)2 D3 , will focus on the potential crosstalk between sphingolipids and 1,25(OH)2 D3 in neural cells.