Low 25(OH) vitamin D3 levels are associated with adverse outcome in newly diagnosed, intensively treated adult acute myeloid leukemia

Telomerase Inhibition in the Treatment of Leukemia: A Comprehensive Review

Leukemia, characterized by the uncontrolled proliferation and differentiation blockage of myeloid or lymphoid precursor cells, presents significant therapeutic challenges despite current treatment modalities like chemotherapy and stem cell transplantation. Pursuing novel therapeutic strategies that selectively target leukemic cells is critical for improving patient outcomes. Natural products offer a promising avenue for developing effective chemotherapy and preventive measures against leukemia, providing a rich source of biologically active compounds. Telomerase, a key enzyme involved in chromosome stabilization and mainly active in cancer cells, presents an attractive target for intervention. In this review article, we focus on the anti-leukemic potential of natural substances, emphasizing vitamins (such as A, D, and E) and polyphenols (including curcumin and indole-3-carbinol), which, in combination with telomerase inhibition, demonstrate reduced cytotoxicity compared to conventional chemotherapies. We discuss the role of human telomerase reverse transcriptase (hTERT), particularly its mRNA expression, as a potential therapeutic target, highlighting the promise of natural compounds in leukemia treatment and prevention.

Vitamin D and potential effects on cancers: a review

Cancer is characterized by the abnormal and uncontrollable division and growth of cells that can infiltrate tissues and alter normal physiological function, which will become crucial and life-threatening if left untreated. Cancer can be a result of genetics, such as mutations or environmental causes, including smoking, lack of physical activity, as well as nutritional imbalance in the body. Vitamin D is one of the foremost nutrients that play a crucial role in a variety of biochemical pathways, and it is an important key factor in several diseases. Vitamin D is an essential nutrient for preventing malignancies and a complementary treatment for cancer through direct and indirect biochemical pathways. In this article, we summarized the correlation between vitamin D and various cancers using an extensive search on PubMed, Google Scholar, and Scopus. This paper reviews the role of vitamin D in different types of cancer.

Vitamin C and D supplementation in acute myeloid leukemia

Recent studies have highlighted the role of vitamin C and D in acute myeloid leukemia (AML). In 2018, we changed our practices to add both vitamins to the supportive care for all consecutive patients with AML undergoing intensive chemotherapy. In this study, we compared the outcomes of patients treated before and after this change in practice. From 2015 to 2020, 431 patients were included, 262 of whom received no supplementation and 169 of whom received vitamin supplementation. Vitamin C and vitamin D was administered from day 10 of chemotherapy until hematologic recovery from induction and consolidation. Most patients presented at diagnosis with low levels of vitamin C and D. Upon recovery from induction, vitamin D levels among the vitamin C/D group significantly increased compared with those at diagnosis, and pretransplant levels were significantly higher in the vitamin C/D group compared with the control group (median of 33 vs 19 ng/mL; P < .0001). During induction, the rates of bacterial or fungal infection, hemorrhage, or macrophage activation syndrome were lower in the vitamin C/D group, whereas there was no difference in response rate, relapse incidence, and overall survival (OS). However, the multivariate analysis for OS showed a significant interaction between vitamin C/D and NPM1 mutation, meaning that vitamin C/D supplementation was significantly and independently associated with better OS in patients with NPM1 mutations (hazard ratio [HR], 0.52; 95% confidence interval [CI], 0.30-0.90; P = .019) compared with patients with wild-type NPM1 (HR, 1.01; 95% CI, 0.68-1.51; P = .95). In conclusion, vitamin C/D supplementation is safe and could influence the outcomes of patients with AML undergoing intensive chemotherapy.

The role of cadmium in the pathogenesis of myeloid leukemia in individuals with anemia, deficiencies in vitamin D, zinc, and low calcium dietary intake

Iron deficiency, vitamin D deficiency and low calcium diet are frequent health problems with severe long- term consequences. Upon absorption from the duodenum, cadmium binds to transferrin, and cells with the highest density of transferrin receptor 1 (TfR1) take up the majority of the circulating cadmium. Nowadays, it is clear that individuals with iron deficiency anemia have increased blood levels of cadmium because of higher absorption rate, mediated by divalent metal transporter 1 (DMT1). However, the transient receptor potential vanilloid receptor 6 (TRPV6), known as a calcium carrier, is able to bind and transport cadmium as well. In the case of low calcium diet or vitamin D deficiency, TRPV6 may be overexpressed in the intestine and kidney tubules and absorbs (re-uptake in the case of renal tubules) cadmium in larger quantities, resulting in an increased cadmium blood levels. We speculate that the final event in the case of low calcium dietary diet and/or vitamin D deficiency is similar to what is observed in the case of iron deficiency, that cells with the highest levels of TfR1 (for example, megakaryocyte/erythrocyte progenitors and pro-erythroblasts) take up most of the circulating cadmium, which is powerful malignancy inductor, leading to appearance of acute myeloid leukemia (AML).

Vitamin D-Binding Protein and Acute Myeloid Leukemia: A Genetic Association Analysis in Combination with Vitamin D Levels

Genetic variations in the vitamin D-binding protein (VDBP) may be associated with the plasma level of serum 25-hydroxyvitamin D. Furthermore, vitamin D deficiency increases the risk of acute myeloid leukemia (AML). This study aimed to examine the potential association of VDBP genetic variants (rs7041 and rs4588) with AML susceptibility. The polymorphisms in the VDBP gene and serum 25-hydroxyvitamin D levels were analyzed in 227 AML patients and 240 healthy controls enrolled in this study. Our data revealed that rs4588 CA and AA genotypes were significantly associated with AML susceptibility (OR = 1.483, p = 0.046; OR = 2.154, p = 0.013, respectively) and also with 61.59% vitamin D deficiency in the total group of AML patients. Under the TG co-dominant and dominant models, however, the rs7041 genotypes were significantly associated with AML protection (OR < 0.6; p < 0.05). In addition, vitamin D deficiency was prevalent in vitamin-D-deficient vs. sufficient AML patients who carried rs7041 and rs4588 mutant alleles (OR ≥ 2.2). Indeed, vitamin D deficiency and its interaction with the genetic variants of VDBP could change the risk of AML. Thus, vitamin D deficiency could be considered an important molecular factor in AML risk assessment.

Modulation of 25(OH) vitamin D3 level by Imatinib mesylate in patients with chronic myelogenous leukaemia: The role of uptake and efflux transporters

Background

Objective

Methods

Results

Conclusions

Preinduction Serum Vitamin D3 Levels and Induction Chemotherapy Remission Rates in Patients with Acute Leukemia

Vitamin D deficiency(<20 ng/mL) is a common condition, associated with an inferior prognosis in some cancers. However, the prognostic significance of vitamin D deficiency in acute leukemia is largely unknown. The present study aimed to assess the baseline status of vitamin D [25-(OH) D3] and find its association with induction remission rate and mortality using standard chemotherapy in patients with acute leukemia. In this prospective observational study, blood samples were collected from 73 newly diagnosed patients before starting induction chemotherapy to measure serum vitamin D [25(OH)D] levels along with routine investigations.44/73 (60.3%) patients were acute lymphoblastic leukemia (ALL), and 29/77 (39.7%) were acute myeloid leukemia (AML) patients. Descriptive statistics and frequency distribution were used in SPSS software, and Pearson's chi-squared test compared the categorical variables. Post-induction remission status (complete and incomplete remission) and induction-related mortality were correlated with vitamin D levels. 44/73 patients (60.3%) included in this study were males, and the remaining were females. The mean age of the participants was 30.32 ± 14.95 years. The mean serum vitamin D level in the cohort was 15.74 ± 28.14 ng/mL. Vitamin D deficiency was observed in 59/73 (80.8%) patients, whereas 14/73 (19.2%) had normal levels (≥20ng/mL) of the vitamin. Vitamin D deficiency is common among acute leukemia patients. Herein, we observed that low vitamin D level is associated with higher rates of incomplete remission in acute leukemia patients (P = 0.016). Vitamin D deficiency is common among acute leukemia patients and is associated with poor short-term outcomes.

Effect of Vitamin D on Graft-versus-Host Disease

The different cell subsets of the immune system express the vitamin D receptor (VDR). Through the VDR, vitamin D exerts different functions that influence immune responses, as previously shown in different preclinical models. Based on this background, retrospective studies explored the impacts of vitamin D levels on the outcomes of patients undergoing allogeneic hematopoietic stem-cell transplantation, showing that vitamin D deficiency is related to an increased risk of complications, especially graft-versus-host disease. These results were confirmed in a prospective cohort trial, although further studies are required to confirm this data. In addition, the role of vitamin D on the treatment of hematologic malignancies was also explored. Considering this dual effect on both the immune systems and tumor cells of patients with hematologic malignancies, vitamin D might be useful in this setting to decrease both graft-versus-host disease and relapse rates.

NAFLD and Vitamin D: Evidence for Intersection of MicroRNA Regulated Pathways

Non-alcoholic fatty liver disease (NAFLD) is now the most common cause of chronic liver disease, worldwide. The molecular pathogenesis of NAFLD is complex, involving numerous signalling molecules including microRNAs (miRNAs). Dysregulation of miRNA expression is associated with hepatic inflammation, fibrosis and hepatocellular carcinoma. Although miRNAs are also critical to the cellular response to vitamin D, mediating regulation of the vitamin D receptor (VDR) and vitamin D’s anticancer effects, a role for vitamin D regulated miRNAs in NAFLD pathogenesis has been relatively unexplored. Therefore, this review aimed to critically assess the evidence for a potential subset of miRNAs that are both dysregulated in NAFLD and modulated by vitamin D. Comprehensive review of 89 human studies identified 25 miRNAs found dysregulated in more than one NAFLD study. In contrast, only 17 studies, including a protocol for a trial in NAFLD, had examined miRNAs in relation to vitamin D status, response to supplementation, or vitamin D in the context of the liver. This paper summarises these data and reviews the biological roles of six miRNAs (miR-21, miR-30, miR-34, miR-122, miR-146, miR-200) found dysregulated in multiple independent NAFLD studies. While modulation of miRNAs by vitamin D has been understudied, integrating the data suggests seven vitamin D modulated miRNAs (miR-27, miR-125, miR-155, miR-192, miR-223, miR-375, miR-378) potentially relevant to NAFLD pathogenesis. Our summary tables provide a significant resource to underpin future hypothesis-driven research, and we conclude that the measurement of serum and hepatic miRNAs in response to vitamin D supplementation in larger trials is warranted.

Impact of vitamin D level at diagnosis and transplantation on the prognosis of hematological malignancy: a meta-analysis

Vitamin D deficiency impairs prognosis in many types of cancer; however, its significance in each subtype of hematological malignancies is unclear. In addition, data on the association between pretransplant vitamin D levels and outcomes of hematopoietic stem cell transplantation (HSCT) are inconsistent. This systematic review and meta-analysis aimed to elucidate the impact of vitamin D levels at diagnosis or pre-HSCT on the prognosis of hematological malignancies. Thirty articles and abstracts were extracted from PubMed, Embase, and Cochrane Library databases and conference proceedings. Fixed and random effect models were used to analyze primary outcomes: overall survival (OS) and progression-free survival (PFS). Lower vitamin D level was significantly associated with poorer OS and PFS in myeloid malignancies (hazard ratio [HR], 1.39; 95% confidence interval [CI], 1.06-1.82 and HR, 2.03; 95% CI, 1.23-3.32, respectively) and lymphoid malignancies (HR, 2.07; 95% CI, 1.79-2.40 and HR, 1.91; 95% CI, 1.61-2.25, respectively), as well as outcomes for several lymphoma subtypes individually. Furthermore, a lower pretransplant vitamin D level was associated with poorer OS in autologous and allogeneic HSCT (HR, 1.65; 95% CI, 1.04-2.61 and HR, 1.50; 95% CI, 1.03-2.18, respectively). Despite the relatively small number of studies evaluated, these data suggest the importance of vitamin D status in outcomes of hematological malignancies (PROSPERO registration number: CRD42020205821).

Vitamin D promotes autophagy in AML cells by inhibiting miR-17-5p-induced Beclin-1 overexpression

MicroRNA (miR)-17-5p has been investigated in many diseases as a regulator of disease progression and is highly expressed in acute myeloid leukemia (AML). However, potential mechanisms underlying the function of miR-17-5p in AML need more elucidation. MiR-17-5p expression was augmented, while 25(OH)D3 and Beclin-1 levels were decreased in AML patients with the highest risk for disease progression. MiR-17-5p, 25(OH)D3 and Beclin-1 were determined to be clinically important in AML based on ROC curve analysis. Higher miR-17-5p expression as well as lower 25(OH)D3 and Beclin-1 expression were relevant with poor prognosis in AML. In addition, miR-17-5p was negatively correlated with and bound to BECN1. Vitamin D was found to diminish cell proliferation and enhance autophagy. Finally, through rescue assays, miR-17-5p facilitated the ability of cell proliferation, inhibited autophagy and apoptosis by modulating Beclin-1 in HL-60 cells following the treatment of 4 μM vitamin D. Vitamin D promoted autophagy in AML cells by modulating miR-17-5p and Beclin-1.

Reviewing the Significance of Vitamin D Substitution in Monoclonal Gammopathies

Vitamin D is a steroid hormone that is essential for bone mineral metabolism and it has several other effects in the body, including anti-cancer actions. Vitamin D causes a reduction in cell growth by interrupting the cell cycle. Moreover, the active form of vitamin D, i.e., 1,25-dihydroxyvitamin D, exerts various effects via its interaction with the vitamin D receptor on the innate and adaptive immune system, which could be relevant in the onset of tumors. Multiple myeloma is a treatable but incurable malignancy characterized by the growth of clonal plasma cells in protective niches in the bone marrow. In patients affected by multiple myeloma, vitamin D deficiency is commonly correlated with an advanced stage of the disease, greater risk of progression, the development of pathological fractures, and a worse prognosis. Changes in the vitamin D receptor often contribute to the occurrence and progress of deficiencies, which can be overcome by supplementation with vitamin D or analogues. However, in spite of the findings available in the literature, there is no clear standard of care and clinical practice varies. Further research is needed to better understand how vitamin D influences outcomes in patients with monoclonal gammopathies.

Nuclear Receptors as Potential Therapeutic Targets for Myeloid Leukemia

The nuclear receptor (NR) superfamily has been studied extensively in many solid tumors and some receptors have been targeted to develop therapies. However, their roles in leukemia are less clear and vary considerably among different types of leukemia. Some NRs participate in mediating the differentiation of myeloid cells, making them attractive therapeutic targets for myeloid leukemia. To date, the success of all-trans retinoic acid (ATRA) in treating acute promyelocytic leukemia (APL) remains a classical and unsurpassable example of cancer differentiation therapy. ATRA targets retinoic acid receptor (RAR) and forces differentiation and/or apoptosis of leukemic cells. In addition, ligands/agonists of vitamin D receptor (VDR) and peroxisome proliferator-activated receptor (PPAR) have also been shown to inhibit proliferation, induce differentiation, and promote apoptosis of leukemic cells. Encouragingly, combining different NR agonists or the addition of NR agonists to chemotherapies have shown some synergistic anti-leukemic effects. This review will summarize recent research findings and discuss the therapeutic potential of selected NRs in acute and chronic myeloid leukemia, focusing on RAR, VDR, PPAR, and retinoid X receptor (RXR). We believe that more mechanistic studies in this field will not only shed new lights on the roles of NRs in leukemia, but also further expand the clinical applications of existing therapeutic agents targeting NRs.

Reduced survival after autologous stem cell transplantation in myeloma and lymphoma patients with low vitamin D serum levels

High-dose chemotherapy (HDCT) with autologous stem cell transplantation (ASCT) is applied for consolidation in myeloma and relapsing lymphoma patients. Vitamin D (VitD) exerts effects during hematopoietic stem cell proliferation, differentiation and interactions with the immune system. VitD deficiency is frequent in patients with hematological malignancies, but its prognostic relevance after ASCT remains unclear. We investigated the effect of VitD serum levels in patients with lymphomas and myeloma at ASCT on progression-free (PFS) and overall survival (OS). The cohort (n = 183) was divided into two groups: 81 (44%) had VitD levels >52 nmol/L and 102 (56%) ≤52 nmol/L at ASCT. VitD levels >52 nmol/L were associated with better PFS (P = 0.0194) and OS (P = 0.011). Similarly, when evaluating myeloma patients alone, patients with lower VitD levels (≤52 nmol/L) had inferior PFS (P = 0.0412) and OS (P = 0.049). Finally, the multivariate analysis was consistent that varying VitD levels were significantly associated with OS (P = 0.0167), also when stratifying patients in groups with VitD levels > versus ≤52 nmol/L (P = 0.0421). Our data suggest that reduced serum VitD levels in myeloma and lymphoma patients undergoing HDCT/ASCT are associated with inferior outcome. Optimizing VitD levels before ASCT may be warranted.

Plasma 25-Hydroxyvitamin D Levels and VDR Gene Expression in Peripheral Blood Mononuclear Cells of Leukemia Patients and Healthy Subjects in Central Kazakhstan

Low blood levels of the vitamin D metabolite 25-hydroxyvitamin D [25(OH)D] have been associated with an increased risk and poorer outcomes of various cancers, including hematological malignancies. The Central Kazakhstan area has a relatively high incidence rate of leukemia. However, the relationship between vitamin D status and leukemia or other types of cancer in Kazakhstan has not yet been addressed. Therefore, in this first pilot single-center study conducted in Central Kazakhstan, we compared plasma levels of 25(OH)D and the vitamin D receptor (VDR) gene expression levels in peripheral blood mononuclear cells of patients with leukemia and demographically matching healthy volunteers. The levels of 25(OH)D in patients were found to be significantly lower (10.8 ± 7.0 ng/mL; n = 31) than in healthy subjects (21.6 ± 7.8 ng/mL; n = 34; p < 0.0001). A similar difference was observed in both younger (<60 years old) and older (>60 years old) participants, though there was no association between 25(OH)D concentration and age within the patient group. In female patients, 25(OH)D levels were significantly lower than in male patients (p = 0.04). No significant seasonal variations of 25(OH)D were observed in either the patient or the control group. VDR gene expression levels appeared to be similar in leukemia patients and healthy subjects, and no correlation between the cellular VDR expression and plasma 25(OH)D concentrations was observed in either group of participants. We did not observe a significant association of 25(OH)D or VDR levels and overall survival of leukemia patients. This observational study conducted for the first time in Kazakhstan supports previous findings demonstrating reduced blood 25(OH)D levels in cancer (leukemia) patients. Larger studies are required to determine whether low 25(OH)D plasma concentrations represent a risk factor for leukemia development and/or progression.

Vitamin D status in children with leukemia, its predictors, and association with outcome

BACKGROUND

Children and adolescents with leukemia are potentially at high risk of vitamin D inadequacy, which may have clinical relevance for skeletal morbidity, infections, and cancer outcome. This study aimed to evaluate vitamin D status at the time of diagnosis to investigate its predictors and association with overall survival in children with leukemia.

PROCEDURE

We included all 295 children and adolescents diagnosed with leukemia at our institution between 1990 and 2016 who had available serum sample from the time of diagnosis. We analyzed serum 25-hydroxyvitamin D and parathyroid hormone levels and correlated them with clinical data.

RESULTS

The 25-hydroxyvitamin D level was deficient (< 25 nmol/L), insufficient (25-50 nmol/L), sufficient (50-75 nmol/L), and optimal (> 75 nmol/L) in 6.4%, 26.8%, 39.7%, and 27.1% of the children, respectively. Older age and a more recent time of sampling (calendar year) predicted lower 25-hydroxyvitamin D level. In preschool children (age ≤6 years), lower 25-hydroxyvitamin D level was also associated with acute myeloid leukemia, and a 25-hydroxyvitamin D level < 50 nmol/L was associated with inferior overall survival. In school-aged children (age > 6 years), the 25-hydroxyvitamin D level showed significant seasonal variation.

CONCLUSION

It remains unclear whether vitamin D supplementation in pediatric leukemia patients will improve outcome.

Role of Vitamins A and D in BCR-ABL Arf-/- Acute Lymphoblastic Leukemia

The effects of vitamin A and/or vitamin D deficiency were studied in an Arf^−/− BCR-ABL acute lymphoblastic leukemia murine model. Vitamin D sufficient mice died earlier (p = 0.003) compared to vitamin D deficient (VDD) mice. Vitamin A deficient (VAD) mice fared worst with more rapid disease progression and decreased survival. Mice deficient for vitamins A and D (VADD) had disease progression similar to VAD mice. Regulatory T cells, previously shown to associate with poor BCR-ABL leukemia control, were present at higher frequencies among CD4⁺ splenocytes of vitamin A deficient vs. sufficient mice. In vitro studies demonstrated 1,25-dihydroxyvitamin D (1,25(OH)₂VD₃) increased the number of BCR-ABL ALL cells only when co-cultured with bone marrow stroma. 1,25(OH)₂VD₃ induced CXCL12 expression in vivo and in vitro in stromal cells and CXCL12 increased stromal migration and the number of BCR-ABL blasts. Vitamin D plus leukemia reprogrammed the marrow increasing production of collagens, potentially trapping ALL blasts. Vitamin A (all trans retinoic acid, ATRA) treated leukemic cells had increased apoptosis, decreased cells in S-phase, and increased cells in G₀/G₁. ATRA signaled through the retinoid X receptor to decrease BCR-ABL leukemic cell viability. In conclusion, vitamin A and D deficiencies have opposing effects on mouse survival from BCR-ABL ALL.

Vitamin D Receptor Controls Cell Stemness in Acute Myeloid Leukemia and in Normal Bone Marrow

Vitamin D (VD) is a known differentiating agent, but the role of VD receptor (VDR) is still incompletely described in acute myeloid leukemia (AML), whose treatment is based mostly on antimitotic chemotherapy. Here, we present an unexpected role of VDR in normal hematopoiesis and in leukemogenesis. Limited VDR expression is associated with impaired myeloid progenitor differentiation and is a new prognostic factor in AML. In mice, the lack of Vdr results in increased numbers of hematopoietic and leukemia stem cells and quiescent hematopoietic stem cells. In addition, malignant transformation of Vdr-/- cells results in myeloid differentiation block and increases self-renewal. Vdr promoter is methylated in AML as in CD34+ cells, and demethylating agents induce VDR expression. Association of VDR agonists with hypomethylating agents promotes leukemia stem cell exhaustion and decreases tumor burden in AML mouse models. Thus, Vdr functions as a regulator of stem cell homeostasis and leukemic propagation.

Regulation of the Immune Balance During Allogeneic Hematopoietic Stem Cell Transplantation by Vitamin D

One of the most promising therapeutic approaches for numerous hematological malignancies represents the allogeneic hematopoietic stem cell transplantation (allo-HSCT). One major complication is the development of the life-threatening graft-vs.-host disease (GvHD) which limits beneficial effects of graft-vs.-leukemia (GvL) responses during allo-HSCT. Strengthening GvL effects without induction of severe GvHD is essential to decrease the relapse rate after allo-HSCT. An interesting player in this context is vitamin D₃ since it has modulatory capacity in both preventing GvHD and boosting GvL responses. Current studies claim that vitamin D₃ induces an immunosuppressive environment by dendritic cell (DC)-dependent generation of regulatory T cells (Tregs). Since vitamin D₃ is known to support the antimicrobial defense by re-establishing the physical barrier as well as releasing defensins and antimicrobial peptides, it might also improve graft-vs.-infection (GvI) effects in patients. Beyond that, alloreactive T cells might be attenuated by vitamin D₃-mediated inhibition of proliferation and activation. Despite the inhibitory effects of vitamin D₃ on T cells, anti-tumor responses of GvL might be reinforced by vitamin D₃-triggered phagocytic activity and antibody-based immunotherapy. Therefore, vitamin D₃ treatment does not only lead to a shift from a pro-inflammatory toward a tolerogenic state but also promotes tumoricidal activity of immune cells. In this review we focus on vitamin D₃ and its immunomodulatory effects by enhancing anti-tumor activity while alleviating harmful allogeneic responses in order to restore the immune balance.

Pretreatment Vitamin D Deficiency Is Associated With Impaired Progression-Free and Overall Survival in Hodgkin Lymphoma

PURPOSE

Vitamin D deficiency is described as a modifiable risk factor for the incidence of and mortality in many common cancers; however, data in Hodgkin lymphoma (HL) are lacking.

PATIENTS AND METHODS

We thus performed a study measuring pretreatment vitamin D levels in prospectively treated patients with HL and correlated this with clinical outcomes. A total of 351 patients from the German Hodgkin Study Group clinical trials (HD7, HD8, and HD9) were included.

RESULTS

Fifty percent of patients were vitamin D deficient (< 30 nmol/L) before planned chemotherapy. Pretreatment vitamin D deficiency was more common in relapsed/refractory patients than matched relapse-free controls (median baseline vitamin D, 21.4 nmol/L v 35.5 nmol/L; proportion with vitamin D deficiency, 68% v 41%; P < .001). Vitamin D-deficient patients had impaired progression-free survival (10-year difference, 17.6%; 95% CI, 6.9% to 28.4%; hazard ratio, 2.13; 95% CI, 1.84 to 2.48; P < .001) and overall survival (10-year difference, 11.1%; 95% CI, 2.1% to 20.2%; hazard ratio, 1.82; 95% CI, 1.53 to 2.15; P < .001), consistent across trials and treatment groups. We demonstrated that vitamin D status is an independent predictor of outcome and hypothesized that vitamin D status might be important for the chemosensitivity of HL. We subsequently performed experiments supplementing physiologic doses of vitamin D (calcitriol) to cultured HL cell lines and demonstrated increased antiproliferative effects in combination with chemotherapy. In an HL-xenograft animal model, we showed that supplemental vitamin D (dietary supplement, cholecalciferol) improves the chemosensitivity of tumors by reducing the rate of tumor growth compared with vitamin D or chemotherapy alone.

CONCLUSION

On the basis of our clinical and preclinical findings, we encourage that vitamin D screening and replacement be incorporated into future randomized clinical trials to properly clarify the role of vitamin D replacement therapy in HL.

Vitamin D and its receptor polymorphisms: New possible prognostic biomarkers in leukemias

Several factors such as chromosomal translocations, gene mutations, and polymorphisms are involved in the pathogenesis of leukemia/lymphoma. Recently, the role of vitamin D (VD) and vitamin D receptor (VDR) polymorphisms in hematologic malignancies has been considered. In this review, we examine the possible role of VD levels, as well as VDR polymorphisms as prognostic biomarkers in leukemia/lymphoma. Relevant English language literature were searched and retrieved from Google Scholar search engine (1985-2017). The following keywords were used: vitamin D, vitamin D receptor, leukemia, lymphoma, and polymorphism. Increased serum levels of VD in patients with leukemia are associated with a better prognosis. However, low VD levels are associated with a poor prognosis, and VDR polymorphisms in various leukemias can have prognostic value. VD biomarker can be regarded as a potential prognostic factor for a number of leukemias, including acute myeloblastic leukemia (AML), chronic lymphoblastic leukemia (CLL), and diffuse large B-cell lymphoma (DLBCL). There is a significant relationship between different polymorphisms of VDR (including Taq I and Fok I) with several leukemia types such as ALL and AML, which may have prognostic value.

Vitamin D: Effect on Haematopoiesis and Immune System and Clinical Applications

Vitamin D is a steroid-like hormone which acts by binding to vitamin D receptor (VDR). It plays a main role in the calcium homeostasis and metabolism. In addition, vitamin D display other important effects called “non-classical actions.” Among them, vitamin D regulates immune cells function and hematopoietic cells differentiation and proliferation. Based on these effects, it is currently being evaluated for the treatment of hematologic malignancies. In addition, vitamin D levels have been correlated with patients’ outcome after allogeneic stem cell transplantation, where it might regulate immune response and, accordingly, might influence the risk of graft-versus-host disease. Here, we present recent advances regarding its clinical applications both in the treatment of hematologic malignancies and in the transplant setting.

The burgeoning role of cytochrome P450-mediated vitamin D metabolites against colorectal cancer

The metabolites of vitamin D₃ (VD3) mediated by different cytochrome P450 (CYP) enzymes, play fundamental roles in many physiological processes in relation to human health. These metabolites regulate a variety of cellular signal pathways through the direct binding of activated vitamin D receptor/retinoic X receptor (VDR/RXR) heterodimeric complex to specific DNA sequences. Thus, the polymorphisms of VDR and VD3 metabolizing enzymes lead to differentiated efficiency of VD3 and further affect serum VD3 levels. Moreover, VDR activation is demonstrated to inhibit the growth of various cancers, including colorectal cancer. However, excessive intake of vitamin D may lead to hypercalcemia, which limits the application of vitamin D tremendously. In this review, we have summarized the advances in VD3 research, especially the metabolism map of VD3 and the molecular mechanisms of inhibiting growth and inducing differentiation in colorectal cancer mediated by VDR-associated cellular signal pathways. The relationship between VDR polymorphism and the risk of colorectal cancer is also illustrated. In particular, novel pathways of the activation of VD3 started by CYP11A1 and CYP3A4 are highlighted, which produce several noncalcemic and antiproliferative metabolites. At last, the hypothesis is put forward that further research of CYP-mediated VD3 metabolites may develop therapeutic agents for colorectal cancer without resulting in hypercalcemia.

Calcitriol-mediated reduction in IFN-γ output in T cell large granular lymphocytic leukemia requires vitamin D receptor upregulation

Constitutively activated STAT1 and elevated IFN-γ are both characteristic of T cell large granular lymphocytic leukemia (T-LGLL), a rare incurable leukemia with clonal expansion of cytotoxic T cells due to defective apoptosis. Interferon gamma (IFN-γ) is an inflammatory cytokine that correlates with worse progression and symptomology in multiple autoimmune diseases and cancers. In canonical IFN-γ-STAT1 signaling, IFN-γ activates STAT1, a transcription factor, via phosphorylation of tyrosine residue 701 (p-STAT1). p-STAT1 then promotes transcription of IFN-γ, creating a positive feedback loop. We previously found that calcitriol treatment of the TL-1 cell line, a model of T-LGLL, significantly decreased IFN-γ secretion and p-STAT1 while increasing the vitamin D receptor (VDR) protein. Here we further explore these observations. Using TL-1 cells, IFN-γ decreased starting at 4h following calcitriol treatment, with a reduction in the intracellular and secreted protein levels as well as the mRNA content. A similar reduction in IFN-γ transcript levels was observed in primary T-LGLL patient peripheral blood mononuclear cells (PBMCs). p-STAT1 inhibition followed a similar temporal pattern and VDR upregulation inversely correlated with IFN-γ levels. Using EB1089 and 25(OH)D₃, which have high or low affinity for VDR, respectively, we found that the decrease in IFN-γ correlated with the ability of EB1089, but not 25(OH)D₃, to upregulate VDR. However, both compounds inhibited p-STAT1; thus the reduction of p-STAT1 is not solely responsible for IFN-γ inhibition. Conversely, cells treated with VDR siRNA exhibited decreased basal IFN-γ production upon VDR knockdown in a dose-dependent manner. Calcitriol treatment upregulated VDR and decreased IFN-γ regardless of initial VDR knockdown efficiency, strengthening the connection between VDR upregulation and IFN-γ reduction. Our findings suggest multiple opportunities to further explore the clinical relevance of the vitamin D pathway and the potential role for vitamin D supplementation in T-LGLL.

The role of VDR and BIM in potentiation of cytarabine-induced cell death in human AML blasts

Acute Myeloid Leukemia (AML) has grave prognosis due to aggressive nature of the disease, the toxicity of standard treatment, and overall low cure rates. We recently showed that AML cells in established culture treated with cytarabine (AraC) and a differentiation agent combination show enhancement of AraC cytotoxicity. Here we elucidate molecular changes which underlie this observation with focus on AML blasts in primary culture. The cells were treated with AraC at concentrations achievable in clinical settings, and followed by the addition of Doxercalciferol, a vitamin D2 derivative (D2), together with Carnosic acid (CA), a plant-derived antioxidant. Importantly, although AraC is also toxic to normal bone marrow cell population, the enhanced cell kill by D2/CA was limited to malignant blasts. This enhancement of cell death was associated with activation of the monocytic differentiation program as shown by molecular markers, and the increased expression of vitamin D receptor (VDR). Apoptosis elicited by this treatment is caspase-dependent, and the optimal blast killing required the increased expression of the apoptosis regulator Bim. These data suggest that testing of this regimen in the clinic is warranted.

Pretransplant Vitamin D Deficiency Is Associated With Higher Relapse Rates in Patients Allografted for Myeloid Malignancies

Purpose Vitamin D (VitD) deficiency is common in patients with hematologic malignancies undergoing allogeneic transplantation (alloSCT), but its prognostic relevance is unclear. Patients and Methods The impact of pretransplant VitD status on overall survival, relapse mortality, and nonrelapse mortality was investigated retrospectively in a cohort of 492 patients undergoing alloSCT at our center from 2002 to 2013. VitD deficiency was defined as a serum level of 25-hydroxyvitamin D3 < 20 ng/mL (equivalent to < 50 nM) before alloSCT and was assessed using accredited laboratory methods and a standard chemiluminescent immunoassay. Results were validated in an independent cohort of 398 patients diagnosed with myeloid malignancies. Results A total of 396 (80%) and 348 (87%) patients had VitD deficiency before alloSCT in the training and validation cohort, respectively. In the training cohort, VitD deficiency was significantly associated with inferior overall survival (hazard ratio [HR], 1.78; P = .007) in multivariable analysis. This was due to a higher risk of relapse (HR, 1.96; P = .006) rather than nonrelapse mortality. A significant association of pretransplant VitD deficiency with higher relapse rates was observed only in patients diagnosed with myeloid (HR, 2.55; P = .014) but not with lymphatic diseases (HR, 1.60; P = .147). A similar impact of pretransplant VitD deficiency on relapse risk in myeloid diseases was also observed in an independent patient cohort (HR, 2.60; P = .017). Validation of the effect of VitD deficiency on relapse in patients with myeloid malignancies was successful. Conclusion Pretransplant VitD deficiency was associated with a higher risk of relapse in patients allografted for myeloid malignancies. Prospective studies on VitD status and correction of VitD deficiency in the setting of alloSCT are highly warranted.

High Prevalence of Vitamin D Deficiency in Newly Diagnosed Acute Myeloid Leukemia Patients and Its Adverse Outcome

Background: Although several studies have supported a preventive and therapeutic role of vitamin D (Vit D) for different types of cancers, we face insufficient documentation in acute myeloid leukemia (AML). So, we examined whether the serum calcidiol (25(OH)D) levels at the time of induction therapy have any impact on response and relapse in AML patients. Materials and Methods: Blood samples were collected from 65 patients on days 0 and 28^th of treatment to evaluate serum concentration of 25(OH)D and its effects on complete remission (CR) achievement, relapse rate and hospitalization length. Results: Of the 65 patients who were included in the study, 38 were male (58.5%) and 27 were female (41.5%). Median age at the time of treatment was 37 years (range 15-68). 6% of the participants were older than 60 years. In regard to 25(OH)D levels, 81.5% of AML patients were deficient (levels <20 ng/ml). There was a significant difference in CR between patients with sufficient and deficient level of 25(OH)D. Deficient patients had longer length of hospitalization than those with sufficient levels. Also Vitamin D deficient patients had higher serum ALP levels. The mean level of 25(OH)D on treatment day 28^th in our study was significantly lower than the baseline value. Conclusion: The results of the study showed that serum 25(OH)D levels deficiency was highly prevalent among Iranian AML patients. Furthermore, higher Vit D levels in AML patients were associated with better outcome in these patients.

Incidence of hematologic malignancy and cause-specific mortality in the Women's Health Initiative randomized controlled trial of calcium and vitamin D supplementation

BACKGROUND

Prior evidence of a possible link between vitamin D status and hematologic malignancy (HM) in humans comes from observational studies, leaving unresolved the question of whether a true causal relationship exists.

METHODS

The authors performed a secondary analysis of data from the Women's Health Initiative Calcium/Vitamin D (CaD) trial, a large randomized controlled trial of CaD supplementation compared with placebo in older women. Kaplan-Meier and Cox proportional hazards survival analysis methods were used to evaluate the relationship between treatment assignment and 1) incident HM and 2) HM-specific mortality over 10 years following randomization. HMs were classified by cell type (lymphoid, myeloid, or plasma cell) and analyzed as distinct endpoints in secondary analyses.

RESULTS

A total of 34,763 Women's Health Initiative CaD trial participants (median age, 63 years) had complete baseline covariate data and were eligible for analysis. Women assigned to CaD supplementation had a significantly lower risk of incident HM (hazard ratio [HR], 0.80; 95% confidence interval [95% CI], 0.65-0.99) but not HM-specific mortality (HR, 0.77 [95% CI, 0.53-1.11] for the entire cohort; and HR, 1.03 [95% CI, 0.70-1.51] among incident HM cases after diagnosis). In secondary analyses, protective associations were found to be most robust for lymphoid malignancies, with HRs of 0.77 (95% CI, 0.59-1.01) and 0.46 (95% CI, 0.24-0.89), respectively, for cancer incidence and mortality in those assigned to CaD supplementation.

CONCLUSIONS

The current post hoc analysis of data from a large and well-executed randomized controlled trial demonstrates a protective association between modest CaD supplementation and HM risk in older women. Additional research concerning the relationship between vitamin D and HM is warranted. Cancer 2017;123:4168-4177. © 2017 American Cancer Society.

The impact of vitamin D pathway genetic variation and circulating 25-hydroxyvitamin D on cancer outcome: systematic review and meta-analysis

BACKGROUND

Vitamin D has been linked with improved cancer outcome. This systematic review and meta-analysis investigates the relationship between cancer outcomes and both vitamin D-related genetic variation and circulating 25-hydroxyvitamin D (25OHD) concentration.

METHODS

A systematic review and meta-analysis of papers until November 2016 on PubMed, EMBASE and Web of Science pertaining to association between circulating vitamin D level, functionally relevant vitamin D receptor genetic variants and variants within vitamin D pathway genes and cancer survival or disease progression was performed.

RESULTS

A total of 44 165 cases from 64 studies were included in meta-analyses. Higher 25OHD was associated with better overall survival (hazard ratio (HR=0.74, 95% CI: 0.66-0.82) and progression-free survival (HR=0.84, 95% CI: 0.77-0.91). The rs1544410 (BsmI) variant was associated with overall survival (HR=1.40, 95% CI: 1.05-1.75) and rs7975232 (ApaI) with progression-free survival (HR=1.29, 95% CI: 1.02-1.56). The rs2228570 (FokI) variant was associated with overall survival in lung cancer patients (HR=1.29, 95% CI: 1.0-1.57), with a suggestive association across all cancers (HR=1.26, 95% CI: 0.96-1.56).

CONCLUSIONS

Higher 25OHD concentration is associated with better cancer outcome, and the observed association of functional variants in vitamin D pathway genes with outcome supports a causal link. This analysis provides powerful background rationale to instigate clinical trials to investigate the potential beneficial effect of vitamin D in the context of stratification by genotype.

Vitamin D in hematological disorders and malignancies

Commonly known for its critical role in calcium homeostasis and bone mineralization, more recently vitamin D has been implicated in hematological cancer pathogenesis and shows promise as an anti-cancer therapy. Serum levels of 25(OH)D₃ , the precursor to the active form of vitamin D, calcitriol, are frequently lower in patients with hematological disease compared to healthy individuals. This often correlates with worse disease outcome. Furthermore, diseased cells typically highly express the vitamin D receptor, which is required for many of the anti-cancer effects observed in multiple in vivo and in vitro cancer models. In abnormal hematological cells, vitamin D supplementation promotes apoptosis, induces differentiation, inhibits proliferation, sensitizes tumor cells to other anti-cancer therapies, and reduces the production of pro-inflammatory cytokines. Although the dosage of vitamin D required to achieve these effects may induce hypercalcemia in humans, analogs and combinatorial treatments have been developed to circumvent this side effect. Vitamin D and its analogs are well tolerated in clinical trials, and thus, further investigation into the use of these agents in the clinic is warranted. Here, we review the current literature in this field.

Single nucleotide polymorphisms in the vitamin D pathway associating with circulating concentrations of vitamin D metabolites and non-skeletal health outcomes: Review of genetic association studies

Polymorphisms in genes encoding proteins involved in vitamin D metabolism and transport are recognised to influence vitamin D status. Syntheses of genetic association studies linking these variants to non-skeletal health outcomes are lacking. We therefore conducted a literature review to identify reports of statistically significant associations between single nucleotide polymorphisms (SNP) in 11 vitamin D pathway genes (DHCR7, CYP2R1, CYP3A4, CYP27A1, DBP, LRP2, CUB, CYP27B1, CYP24A1, VDR and RXRA) and non-bone health outcomes and circulating levels of 25-hydroxyvitamin D (25[OH]D and 1,25-dihydroxyvitamin D (1,25[OH]₂D). A total of 120 genetic association studies reported positive associations, of which 44 investigated determinants of circulating 25(OH)D and/or 1,25(OH)₂D concentrations, and 76 investigated determinants of non-skeletal health outcomes. Statistically significant associations were reported for a total of 55 SNP in the 11 genes investigated. There was limited overlap between genetic determinants of vitamin D status and those associated with non-skeletal health outcomes: polymorphisms in DBP, CYP2R1 and DHCR7 were the most frequent to be reported to associate with circulating concentrations of 25(OH)D, while polymorphisms in VDR were most commonly reported to associate with non-skeletal health outcomes, among which infectious and autoimmune diseases were the most represented.

25-Hydroxyvitamin D and TSH as Risk Factors or Prognostic Markers in Thyroid Carcinoma

Objective

The increasing incidence of thyroid nodules demands identification of risk factors for malignant disease. Several studies suggested the association of higher TSH levels with cancer, but influence of 25-hydroxyvitamin D (25OHD) is controversial. This study aimed to identify the relationship of thyroid cancer with higher TSH levels and hypovitaminosis D and to evaluate their influence on prognostic characteristics of papillary thyroid carcinomas (PTC).

Methods

We retrospectively evaluated 433 patients submitted to thyroidectomy for thyroid nodules. Patients were categorized according to quartiles of TSH and 25OHD levels. Clinicopathological features were analyzed.

Results

Subjects with thyroid carcinomas were more frequently male and younger compared to those with benign disease. Their median TSH levels were higher and adjusted odds-ratio (OR) for cancer in the highest-quartile of TSH (> 2.4 mUI/mL) was 2.36 (1.36–4.09). Although vitamin D deficiency/insufficiency was prevalent in our cohort (84%), no significant differences in 25OHD levels or quartile distribution were observed between benign and malignant cases. Among 187 patients with PTC, analyses of prognostic features revealed increased risk of lymph nodes metastases for subjects with highest-quartile TSH levels (OR = 3.7, p = 0.029). Decreased 25OHD levels were not overtly associated with poor prognosis in PTC.

Conclusions

In this cross-sectional cohort, higher TSH levels increased the risk of cancer in thyroid nodules and influenced its prognosis, particularly favoring lymph nodes metastases. On the other hand, no association was found between 25OHD levels and thyroid carcinoma risk or prognosis, suggesting that serum 25OHD determination may not contribute to risk assessment workup of thyroid nodules.

Prodifferentiation Activity of Novel Vitamin D₂ Analogs PRI-1916 and PRI-1917 and Their Combinations with a Plant Polyphenol in Acute Myeloid Leukemia Cells

1α,25-dihydroxyvitamin D₃ (1,25D3) is a powerful differentiation inducer for acute myeloid leukemia (AML) cells. However, 1,25D3 doses required for differentiation of AML cells may cause lethal hypercalcemia in vivo. There is evidence that vitamin D₂ is less toxic than vitamin D₃ in animals. Here, we determined the differentiation effects of novel analogs of 1α,25-dihydroxyvitamin D₂ (1,25D2), PRI-1916 and PRI-1917, in which the extended side chains of their previously reported precursors (PRI-1906 and PRI-1907, respectively) underwent further 24Z (24-cis) modification. Using four human AML cell lines representing different stages of myeloid maturation (KG-1a, HL60, U937, and MOLM-13), we found that the potency of PRI-1916 was slightly higher or equal to that of PRI-1906 while PRI-1917 was significantly less potent than PRI-1907. We also demonstrated that 1,25D2 was a less effective differentiation agent than 1,25D3 in these cell lines. Irrespective of their differentiation potency, all the vitamin D₂ derivatives tested were less potent than 1,25D3 in transactivating the DR3-type vitamin D response elements. However, similar to 1,25D3, both 1,25D2 and its analogs could strongly cooperate with the plant polyphenol carnosic acid in inducing cell differentiation and inhibition of G1–S cell cycle transition. These results indicate that the 24Z modification has contrasting effects on the differentiation ability of PRI-1906 and PRI-1907 and that the addition of a plant polyphenol could result in a similar extent of cell differentiation induced by different vitamin D compounds. The enhanced antileukemic effects of the tested combinations may constitute the basis for the development of novel approaches for differentiation therapy of AML.

The role of vitamin D in cancer prevention

Vitamin D, also known as cholecalciferol, is the precursor to the active steroid hormone 1, 25-dihydroxyvitamin D3 (calcitriol; 1, 25(OH)2D3). The main physiological role for 1, 25(OH)2D3 is to regulate calcium and inorganic phosphate homeostasis for bone health. More recently, vitamin D has been investigated for its effects in the prevention and treatment of a variety of diseases such as cancer, autoimmune disorders, and cardiovascular disease. Preclinical data strongly support a role for vitamin D in the prevention of cancer through its anti-proliferative, pro-apoptotic, and anti-angiogenic effects on cells. Epidemiologic and clinical studies have shown mixed data on the correlation between serum vitamin D levels and cancer risk. This report seeks to outline results from the most recent preclinical and clinical studies investigating the potential role of vitamin D in cancer prevention.

DNA Repair in Despair-Vitamin D Is Not Fair

The role of vitamin D as a treatment option for neoplastic diseases, once considered to have a bright future, remains controversial. The preclinical studies discussed herein show compelling evidence that Vitamin D Derivatives (VDDs) can convert some cancer and leukemia cells to a benign phenotype, by differentiation/maturation, cell cycle arrest, or induction of apoptosis. Furthermore, there is considerable, though still evolving, knowledge of the molecular mechanisms underlying these changes. However, the attempts to clearly document that the treatment outcomes of human neoplastic diseases can be positively influenced by VDDs have been, so far, disappointing. The clinical trials to date of VDDs, alone or combined with other agents, have not shown consistent results. It is our contention, shared by others, that there were limitations in the design or execution of these trials which have not yet been fully addressed. Based on the connection between upregulation of JNK by VDDs and DNA repair, we propose a new avenue of attack on cancer cells by increasing the toxicity of the current, only partially effective, cancer chemotherapeutic drugs by combining them with VDDs. This can impair DNA repair and thus kill the malignant cells, warranting a comprehensive study of this novel concept. J. Cell. Biochem. 117: 1733-1744, 2016. © 2016 Wiley Periodicals, Inc.

Vitamin D Control of Hematopoietic Cell Differentiation and Leukemia

It is now well known that in the mammalian body vitamin D is converted by successive hydroxylations to 1,25-dihydroxyvitamin D (1,25D), a steroid-like hormone with pleiotropic properties. These include important contributions to the control of cell proliferation, survival and differentiation, as well as the regulation of immune responses in disease. Here, we present recent advances in current understanding of the role of 1,25D in myelopoiesis and lymphopoiesis, and the potential of 1,25D and analogs (vitamin D derivatives; VDDs) for the control of hematopoietic malignancies. The reasons for the unimpressive results of most clinical studies of the therapeutic effects of VDDs in leukemia and related diseases may include the lack of a precise rationale for the conduct of these studies. Further, clinical trials to date have generally used extremely heterogeneous patient populations and, in many cases, small numbers of patients, generally without controls. Although low calcemic VDDs have been used and combined with agents that can increase the leukemia cell killing or differentiation effects in acute leukemias, the sequencing of agents used for combination therapy should to be more clearly delineated. Most importantly, it is recommended that in future clinical trials the rationale for the basis of the enhancing action of drug combinations should be clearly articulated and the effects on anticancer immunity should also be evaluated.

Low Vitamin D Levels Are Associated With an Adverse Clinical Outcome in Febrile Neutropenia

AIM

The aim of the study was to evaluate the levels of vitamin D in patients of aplastic anemia presenting with febrile neutropenia and its association with clinically important parameters.

MATERIALS AND METHODS

The 25-hydroxy vitamin D (25(OH)D) levels were measured in 35 patients of aplastic anemia with febrile neutropenia in the age group of 4 to 16 years. About 30 healthy children served as controls. Vitamin D deficiency was defined as 25(OH)D<20 ng/mL, insufficiency 20 to 29 ng/mL, and sufficiency≥30 ng/mL.

RESULTS

The median age of patients was 9.3 years. The mean 25(OH)D level was 17.71±8.90 ng/mL in patients against 23.67±10.80 ng/mL in the control group (P<0.01). About 65.7% of the patients were 25(OH)D deficient (<20 ng/mL). Only 8.6% had sufficient levels. Older (above 10 y) patients, male children, and those from a rural background and a low socioeconomic status had significantly lower 25(OH)D levels as compared with controls. Low 25(OH)D levels were associated with a longer duration (≥7 d) of febrile neutropenia (17.26±7.19 vs. 20.01±12.12 ng/mL) although the difference was not statistically significant. Two patients who expired had significantly lower 25(OH)D levels (12.85±4.12 ng/mL) compared with those who improved (22.86±6.47 ng/mL, P<0.05).

CONCLUSIONS

A high prevalence of vitamin D deficiency was observed in patients with febrile neutropenia. Low levels were associated with an adverse clinical outcome.

Low serum vitamin D occurs commonly among multiple myeloma patients treated with bortezomib and/or thalidomide and is associated with severe neuropathy

PURPOSE

Previous studies have shown that low serum vitamin D levels have been associated with many skeletal and non-skeletal disorders. We studied the relationship between 25-hydroxyvitamin D (25D) levels and motor and sensory peripheral neuropathy (PN) among multiple myeloma (MM) patients who have been treated with bortezomib and/or thalidomide.

METHODS

We performed a study of 111 MM patients who had received at least one of these two agents for at least 12 weeks by correlating physical exam/neurologic assessment findings with patient self-assessment responses.

RESULTS

The median age of study patients was 66 years (range 42-89 years) and 54 % were males. 25D levels were determined, and complete history and physical and neurologic examinations were performed at the same study visit. In addition, study subjects completed questionnaires regarding symptoms related to motor and sensory PN. Overall, patients had a median serum 25D level of only 32 ng/ml; 42 % of patients were considered either 25D-deficient (<20.0 ng/mL; 16 % of patients) or 25D-insufficient (20.0-29.9 ng/mL; 26 %). Notably, we found that 25D-deficient MM patients were more likely to have severe PN (>grade 2) of both motor (p = 0.0415) and sensory (p = 0.0086) types although the overall incidence of PN was not higher in this patient population.

CONCLUSION

These results show that the severity of peripheral neuropathy is associated with lower vitamin D levels and provides the rationale for monitoring vitamin D for myeloma patients especially those receiving drugs associated with the development of peripheral neuropathy.

Low serum vitamin D levels are associated with shorter survival after first-line azacitidine treatment in patients with myelodysplastic syndrome and secondary oligoblastic acute myeloid leukemia

BACKGROUND & AIMS

Azacitidine (AZA) therapy has become the recommended first-line treatment for patients with high-risk myelodysplastic syndromes (MDS) and oligoblastic (<30% bone marrow blasts) acute myeloid leukemia (AML). However, improvement of the efficacy of AZA treatment remains a challenge. We retrospectively tested the hypothesis that VitD levels (25-hydroxyvitamin D3) prior to start of first-line AZA therapy are predictive of overall survival (OS) in patients diagnosed with MDS and secondary oligoblastic AML. Furthermore, the antiproliferative effects of AZA in combination with 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3 were investigated in vitro.

METHODS

A total of 58 patients treated at our center between 2006 and 2014 were analyzed. Serum levels of VitD were quantified using a standard, commercially available 25-hydroxyvitamin D3 chemiluminescent immunoassay. Effects on cell proliferation were assessed using tetrazolium-based MTT assays.

RESULTS

Median serum VitD level prior to AZA treatment was 32.8 nM (range 11.0-101.5 nM). Patient, disease and treatment characteristics did not differ significantly between the low (≤32.8 nM; n = 29) and high (>32.8 nM; n = 29) VitD group. Estimated probability of 2-year OS in the low versus high VitD group was 14% versus 40% (P < 0.05). In multivariable analysis with OS as endpoint, adverse cytogenetics (HR 2.66, P = 0.03) and VitD (per 10 nM decrease, HR 1.68, P = 0.02) were independent predictors of worse survival. In-vitro treatment of myeloid cell lines with AZA in combination with VitD produced synergistic and additive antiproliferative effects. Addition of nanomolar VitD concentrations to AZA resulted in potentiation of AZA activity. Conversely, combination with the VitD antagonist TEI-9647 resulted in inhibition of AZA activity.

CONCLUSIONS

Our study suggests that higher VitD levels were associated with a survival advantage following first-line AZA therapy. Enhanced cytotoxic effects upon combination treatment may contribute to the observed clinical effects. VitD repletion/supplementation during AZA treatment should be explored.

Low Cloud Cover-Adjusted Ultraviolet B Irradiance Is Associated with High Incidence Rates of Leukemia: Study of 172 Countries

There are 52,380 cases of leukemia and 24,090 deaths from it in the US annually. Its causes are unknown and no preventive strategies have been implemented. We hypothesized that leukemia is due mainly to vitamin D deficiency, which is due mainly to low solar ultraviolet B (UVB) irradiance. To test this hypothesis, we estimated age-standardized cloud-cover-adjusted winter UVB irradiance using cloud cover data from the International Satellite Cloud Climatology Project, latitudes of population centroids, and standard astronomical calculations. Incidence rates for 172 countries, available from the International Agency for Cancer Research, were plotted according to cloud-adjusted UVB irradiance. We used multiple regression to account for national differences in elevation and average life expectancy. Leukemia incidence rates were inversely associated with cloud-adjusted UVB irradiance in males (p ≤ 0.01) and females (p ≤ 0.01) in both hemispheres. There were few departures from the trend line, which was parabolic when plotted with the equator at the center of the display, northern hemisphere countries on the right side and southern hemisphere countries on the left. The bivariate association displayed by the polynomial trend line indicated that populations at higher latitudes had at least two times the risk of leukemia compared to equatorial populations. The association persisted in males (p ≤ 0.05) and females (p ≤ 0.01) after controlling for elevation and life expectancy. Incidence rates of leukemia were inversely associated with solar UVB irradiance. It is plausible that the association is due to vitamin D deficiency. This would be consistent with laboratory studies and a previous epidemiological study. Consideration should be given to prudent use of vitamin D for prevention of leukemia.

Impact of p53 Status on Radiosensitization of Tumor Cells by MET Inhibition-Associated Checkpoint Abrogation

Signaling via the MET receptor tyrosine kinase has been implicated in crosstalk with cellular responses to DNA damage. Our group previously demonstrated that MET inhibition in tumor cells with deregulated MET activity results in radiosensitization via downregulation of the ATR-CHK1-CDC25 pathway, a major signaling cascade responsible for intra-S and G2-M cell-cycle arrest following DNA damage. Here we aimed at studying the potential therapeutic application of ionizing radiation in combination with a MET inhibitor, EMD-1214063, in p53-deficient cancer cells that harbor impaired G1-S checkpoint regulation upon DNA damage. We hypothesized that upon MET inhibition, p53-deficient cells would bypass both G1-S and G2-M checkpoints, promoting premature mitotic entry with substantial DNA lesions and cell death in a greater extent than p53-proficient cells. Our data suggest that p53-deficient cells are more susceptible to EMD-1214063 and combined treatment with irradiation than wild-type p53 lines as inferred from elevated γH2AX expression and increased cytotoxicity. Furthermore, cell-cycle distribution profiling indicates constantly lower G1 and higher G2-M population as well as higher expression of a mitotic marker p-histone H3 following the dual treatment in p53 knockdown isogenic variant, compared with the parental counterpart.

IMPLICATIONS

The concept of MET inhibition-mediated radiosensitization enhanced by p53 deficiency is of high clinical relevance, as p53 is frequently mutated in numerous types of human cancer. The current data point for a therapeutic advantage for an approach combining MET targeting along with DNA-damaging agents for MET-positive/p53-negative tumors.

Vitamin D and Bone Minerals Status in the Long-term Survivors of Childhood Acute Lymphoblastic Leukemia

Background:

Low vitamin D and diminished bone minerals with the potential for fractures are one of the nonapparent late effects of acute lymphoblastic leukemia (ALL). Chemotherapy and radiation were known as two important risk factors. We evaluated these late effects in ALL survivors who were treated with chemotherapy or chemo plus cranial radiation therapy.

Methods:

In a case–control study, 33 of ALL survivors who were treated with chemotherapy (Group A), and 33 subjects who were treated with chemoplus cranial radiation (Group B) were compared against 33 matched age, sex, and pubertal stage of their healthy siblings (Group C). Standard anthropometric data were collected as well as Tanner staging for puberty, number of fractures since treatment, serum calcium (Ca), phosphorus (P), magnesium (Mg), alkaline phosphatase, parathyroid hormone, and 25-hydroxyvitamin D (25(OH) D). The independent t-test, one-way ANOVA, Chi-square test, and Tukey's test were used to analyze the data.

Results:

The findings indicated that the mean serum levels of 25(OH) D in ALL survivors (i.e. Groups A and B) with age mean score of 11.2 years and 12.3 years, average treatment length: 3.25 years and average time after treatment completion: 4 years, was lower compared to the controls group (12.94 ± 6.69, 14.6 ± 8.1, 20.16 ± 10.83, respectively, P < 0.001) but no significant difference was observed between Group A and B in this regard (P > 0.05). Other clinical and laboratory parameters had no significant differences between the survivors and control. Vitamin D deficiency (<20 ng/ml) was observed in 27% of group A and 24% of group B and vitamin D insufficiency (20–30 ng/ml) in 72.7% and 69.6% survivors of Group A and B and 48.5% of controls group (P = 0.003).

Conclusions:

ALL treatment is associated with the increase in prevalence of vitamin D insufficiency in the childhood ALL survivors and since the low vitamin D level potentially increases the risk of low bone density, subsequent malignancies, and cardiovascular disease in the survivors, close follow-up of such patients are highly recommended to prevent the stated complications.

The Potential of Vitamin D-Regulated Intracellular Signaling Pathways as Targets for Myeloid Leukemia Therapy

The current standard regimens for the treatment of acute myeloid leukemia (AML) are curative in less than half of patients; therefore, there is a great need for innovative new approaches to this problem. One approach is to target new treatments to the pathways that are instrumental to cell growth and survival with drugs that are less harmful to normal cells than to neoplastic cells. In this review, we focus on the MAPK family of signaling pathways and those that are known to, or potentially can, interact with MAPKs, such as PI3K/AKT/FOXO and JAK/STAT. We exemplify the recent studies in this field with specific relevance to vitamin D and its derivatives, since they have featured prominently in recent scientific literature as having anti-cancer properties. Since microRNAs also are known to be regulated by activated vitamin D, this is also briefly discussed here, as are the implications of the emerging acquisition of transcriptosome data and potentiation of the biological effects of vitamin D by other compounds. While there are ongoing clinical trials of various compounds that affect signaling pathways, more studies are needed to establish the clinical utility of vitamin D in the treatment of cancer.

Review: the impacts of circulating 25-hydroxyvitamin D levels on cancer patient outcomes: a systematic review and meta-analysis

CONTEXT

Circulating levels of 25-hydroxyvitamin D [25(OH)D] may affect the prognosis of cancer patients; however, the epidemiological results are not consistent.

OBJECTIVE

To perform a meta-analysis of all published studies to assess the associations of circulating 25(OH)D levels measured at or near the time of diagnosis and outcomes for cancer patients.

DATA SOURCES

Searches of the PubMed and MEDLINE databases were performed and updated to December 2013.

STUDY SELECTION

Studies reporting an association between circulating 25(OH)D levels at or near the time of diagnosis and outcomes for the patients were included.

DATA EXTRACTION

Data extraction was performed independently by two authors, and conflicts were resolved by a third investigator.

DATA SYNTHESIS

Included in the meta-analysis were 25 studies with 17 332 cases. Significant associations between circulating 25(OH)D levels at or near the time of diagnosis and the outcomes for cancer patients were found. The pooled hazard ratio for the highest vs the lowest quartile of circulating 25(OH)D levels was 0.55 (95% confidence interval [CI] = 0.33-0.91) for overall survival of colorectal cancer patients, 0.63 (95% CI = 0.51-0.77) for breast cancer patients, and 0.48 (95% CI = 0.36-0.64) for lymphoma patients. Higher 25(OH)D levels were significantly associated with reduced cancer-specific mortality for patients with colorectal cancer (P = .005) and lymphoma (P < .001) and improved disease-free survival for patients with breast cancer (P < .001) or lymphoma (P < .05). A 10-nmol/L increment in circulating 25(OH)D levels conferred a hazard ratio of 0.96 (95% CI = 0.95-0.97) for overall survival of the cancer patients.

CONCLUSIONS

The results indicate that cancer patients with higher circulating 25(OH)D levels at or near the time of diagnosis have better outcomes.