Vitamin D3 enhances the tumouricidal effects of 5-Fluorouracil through multipathway mechanisms in azoxymethane rat model of colon cancer.
ABSTRACT: Vitamin D3 and its analogues have recently been shown to enhance the anti-tumour effects of 5- Fluorouracil (5-FU) both in vitro and in xenograft mouse model of colon cancer. This study measured the potential mechanism(s) by which vitamin D3 could synergise the tumouricidal activities of 5-FU in azoxymethane (AOM) rat model of colon cancer.Seventy-five male Wistar rats were divided equally into 5 groups: Control, AOM, AOM-treated by 5-FU (5-FU), AOM-treated by vitamin D3 (VitD3), and AOM-treated by 5-FU?+?vitamin D3 (5-FU/D). The study duration was 15 weeks. AOM was injected subcutaneously for 2 weeks (15 mg/kg/week). 5-FU was injected intraperitoneally in the 9th and 10th weeks post AOM (8 total injections were given: 12 mg/kg/day for 4 successive days, then 6 mg/kg every other day for another 4 doses) and oral vitamin D3 (500 IU/rat/day; 3 days/week) was given from week 7 post AOM till the last week of the study. The colons were collected following euthanasia for gross and histopathological examination. The expression of ?-catenin, transforming growth factor-?1 (TGF-?1), TGF-? type 2 receptor (TGF-?R2), smad4, inducible nitric oxide synthase (iNOS), and heat shock protein-90 (HSP-90) proteins was measured by immunohistochemistry. In colonic tissue homogenates, quantitative RT-PCR was used to measure the mRNA expression of Wnt, ?-catenin, Dickkopf-1 (DKK-1) and cyclooxygenase-2 (COX-2) genes, while ELISA was used to measure the concentrations of TGF-?1, HSP-90 and COX-2 proteins.Monotherapy with 5-FU or vitamin D3 significantly decreased the number of grown tumours induced by AOM (P?
Project description:Colorectal cancer (CRC) is one of the most prevalent cancers and has a high mortality rate. Insensitivity and the limited therapeutic efficacy of its standard chemotherapeutic drug, 5-fluorouracil (5-FU), represents an important challenge in CRC treatment. The robust antitumor properties of thymoquinone (TQ), the main bioactive constituent of Nigella sativa, have recently been demonstrated on different cancers. We investigated whether TQ could potentiate the chemopreventive effect of 5-FU to eradicate the early stages of CRC and elucidated its underlying mechanisms. An intermediate-term (15 weeks) model of colorectal tumorigenesis was induced in male Wistar rats by azoxymethane (AOM), and the animals were randomly and equally divided into five groups: control, AOM, AOM/5-FU, AOM/TQ, and AOM/5-FU/TQ. TQ (35 mg/kg/d; 3 d/wk) was given during the seventh and 15th weeks post-AOM injection, while 5-FU was given during the ninth and tenth weeks (12 mg/kg/d for 4 days; then 6 mg/kg every other day for another four doses). At week 15, the resected colons were subjected to macroscopic, histopathological, molecular, and immunohistochemical examinations. Interestingly, 5-FU/TQ combination therapy resulted in a more significant reduction on AOM-induced colorectal tumors and large aberrant crypts foci than treatment with the individual drugs. Mechanistically, 5-FU and TQ remarkably cooperated to repress the expression of procancerous Wnt, ?-catenin, NF-?B, COX-2, iNOS, VEGF, and TBRAS and upregulate the expression of anti-tumorigenesis DKK-1, CDNK-1A, TGF-?1, TGF-?RII, Smad4, and GPx. Overall, our findings present the first report describing the in vivo enhancement effect of combined TQ and 5-FU against early stages of CRC; however, further studies are required to determine the value of this combination therapy in an advanced long-term model of CRC and also to realize its clinical potential.
Project description:Prevention of colon cancer among high-risk group has been long lasting research goal. Emerging data have evidenced the anticancer activities of Vitamin D3 (Vit.D) and Thymoquinone (TQ). The aim of the current study was to evaluate the synergistic potential of Thymoquinone and Vitamin D3 in the control of colon cancer progression using azoxymethane-induced rat model. Vit.D and TQ were given individually or in combination 4 week prior to induction and continued for a total of 20 week. At the end of the study, all animals were euthanized and their resected colons were examined macroscopically and microscopically for tumor growth. Colonic tissue preparations were used for measuring gene expression and/or protein levels of selected pro and anti-tumor biomarkers using quantitative RT-PCR, ELISA and immunohistochemistry. Compared with their individual supplementation, combined Vit.D/TQ showed prominent anti-tumor effect manifested by significant reduction (P < 0.05) of the numbers of grown tumors and large aberrant crypts foci. Mechanistically, gene expression and/or protein quantification studies revealed that combined Vit.D/TQ supplementation induced significant reduction (P < 0.01 and P < 0.05) of pro-cancerous molecules (Wnt, ?-catenin, NF-?B, COX-2, iNOS, VEGF and HSP-90) as well as significant increase (P < 0.01 and P < 0.05, respectively) of anti-tumorigenesis biomarkers (DKK-1, CDNK-1A, TGF-?1, TGF-?/RII and smad4) as compared to un-supplemented or individually supplemented groups, respectively. In conclusion, TQ augmented the chemopreventive effect of Vit.D during the initiation phase of colon cancer in rat model, with the potential to suppress progression of pre-neoplastic lesions in colon carcinogenesis.
Project description:Low vitamin D status is associated with progression in patients with renal cell carcinoma (RCC). The present study found that vimentin, a mesenchymal marker, was accordingly upregulated, and E-cadherin, an epithelial marker, was downregulated in RCC patients with low vitamin D status. Thus, we investigated the effects of calcitriol or vitamin D3, an active form of vitamin D, on epithelial-mesenchymal transition (EMT) in RCC cells. RCC cells were treated by two models. In model 1, three RCC cell lines, ACHN, 786-O and CAKI-2, were incubated with either LPS (2.0 ?g/mL) or transforming growth factor (TGF)-?1 (10 ng/mL) in the presence or absence of calcitriol (200 nmol/L). In model 2, two RCC cell lines, ACHN and CAKI-2, were incubated with calcitriol (200 nmol/L) only. Calcitriol inhibited migration and invasion not only in TGF-?1-stimulated but also in TGF-?1-unstimulated RCC cells. Moreover, calcitriol suppressed E-cadherin downregulation and vimentin upregulation not only in TGF-?1-stimulated but also in TGF-?1-unstimulated ACHN and CAKI-2 cells. Calcitriol attenuated LPS-induced upregulation of MMP-2, MMP-7, MMP-9, MMP-26 and urokinase-type plasminogen activator (u-PA) in ACHN cells. In addition, calcitriol blocked TGF-?1-induced nuclear translocation of ZEB1, Snail and Twist1 in ACHN and CAKI-2 cells. Mechanistically, calcitriol suppressed EMT through different signaling pathways: (i) calcitriol suppressed Smad2/3 phosphorylation by reinforcing physical interaction between vitamin D receptor (VDR) and Smad3 in TGF-?1-stimulated RCC cells; (ii) calcitriol inhibited signal transducer and activator of transcription (STAT)3 activation in LPS-stimulated RCC cells; (iii) calcitriol inhibited ?-catenin/TCF-4 activation by promoting integration of VDR with ?-catenin in TGF-?1-unstimulated RCC cells. Taken together, calcitriol inhibits migration and invasion of RCC cells partially by suppressing Smad2/3-, STAT3- and ?-catenin-mediated EMT.
Project description:We previously showed that EGF receptor (EGFR) promotes tumorigenesis in the azoxymethane/dextran sulfate sodium (AOM/DSS) model, whereas vitamin D suppresses tumorigenesis. EGFR-vitamin D receptor (VDR) interactions, however, are incompletely understood. Vitamin D inhibits the renin-angiotensin system (RAS), whereas RAS can activate EGFR. We aimed to elucidate EGFR-VDR cross-talk in colorectal carcinogenesis.To examine VDR-RAS interactions, we treated Vdr(+/+) and Vdr(-/-) mice with AOM/DSS. Effects of VDR on RAS and EGFR were examined by Western blotting, immunostaining, and real-time PCR. We also examined the effect of vitamin D3 on colonic RAS in Vdr(+/+) mice. EGFR regulation of VDR was examined in hypomorphic Egfr(Waved2) (Wa2) and Egfr(wild-type) mice. Angiotensin II (Ang II)-induced EGFR activation was studied in cell culture.Vdr deletion significantly increased tumorigenesis, activated EGFR and ?-catenin signaling, and increased colonic RAS components, including renin and angiotensin II. Dietary VD3 supplementation suppressed colonic renin. Renin was increased in human colon cancers. In studies in vitro, Ang II activated EGFR and stimulated colon cancer cell proliferation by an EGFR-mediated mechanism. Ang II also activated macrophages and colonic fibroblasts. Compared with tumors from Egfr(Waved2) mice, tumors from Egfr(wild-type) mice showed upregulated Snail1, a suppressor of VDR, and downregulated VDR.VDR suppresses the colonic RAS cascade, limits EGFR signals, and inhibits colitis-associated tumorigenesis, whereas EGFR increases Snail1 and downregulates VDR in colonic tumors. Taken together, these results uncover a RAS-dependent mechanism mediating EGFR and VDR cross-talk in colon cancer.
Project description:Transforming growth factor alpha (TGF?) and TGF?1 are growth-promoting and -inhibiting autocrine/paracrine growth factors, respectively, that may (1) affect risk for colorectal cancer and (2) be modifiable by anti-proliferative exposures. The effects of supplemental calcium and vitamin D3 on these two markers in the normal-appearing colorectal mucosa in humans are unknown. We conducted a pilot, randomized, double-blind, placebo-controlled, 2 × 2 factorial clinical trial (n = 92; 23/treatment group) of calcium 2 g and/or vitamin D3 800 IU/d versus placebo over 6 mo. TGF? and TGF?1 expression was measured in biopsies of normal-appearing rectal mucosa using automated immunohistochemistry and quantitative image analysis at baseline and 6-mo follow-up. In the calcium, vitamin D3 , and calcium plus vitamin D3 groups relative to the placebo group (1) the mean overall expression of TGF?1 increased by 14% (P= 0.25), 19% (P = 0.17), and 22% (P = 0.09); (2) the ratio of TGF? expression in the upper 40% (differentiation zone) to that in the lower 60 (proliferation zone) of the crypts decreased by 34% (P = 0.11), 31% (P = 0.22), and 26% (P = 0.33); and (3) the TGF?/TGF?1 ratio in the upper 40% of the crypts decreased by 28% (P = 0.09), 14% (P = 0.41), and 22% (P = 0.24), respectively. These preliminary results, although not statistically significant, suggest that supplemental calcium and vitamin D3 may increase TGF?1 expression and shift TGF? expression downward from the differentiation to the proliferation zone in the crypts in the normal-appearing colorectal mucosa of sporadic colorectal adenoma patients, and support further investigation in a larger clinical trial.
Project description:Vitamin D is implicated in the etiology of cancers of the gastrointestinal tract, usually characterized by alteration in the APC/?-catenin/TCF tumor suppressor pathway. The vitamin D receptor (VDR) is also implicated in cardiovascular and skin diseases as well as in immunity. Activated VDR can indirectly alter ?-catenin nuclear localization and directly suppress ?-catenin/TCF mediated transcriptional activity. We treated VDR null mice with the carcinogen azoxymethane (AOM) and generated mice bearing a mutated APC (hypomorph) on a VDR null background (Apc1638N/+Vdr-/-). VDR null mice do not develop GI or extra-colonic tumors but loss of VDR decreased intestinal tumor latency and increased progression to adenocarcinoma in both models. AOM treatment of VDR null mice also caused squamous cell carcinoma of the anus. Although levels and distribution of total or activated ?-catenin in the epithelial component of tumors were unaffected by loss of VDR, ?-catenin dependent cyclin D1 expression was affected suggesting a direct VDR effect on ?-catenin co-activator activity. Extra-colonic mucosa manifestations in Apc1638N/+Vdr-/- animals included increased nuclear ?-catenin in submucosal stromal cells, spleno- and cardiomegaly and large epidermoid cysts characteristic of the FAP variant, Gardner's syndrome. Consistent with this, SNPs in the VDR, vitamin D binding protein and CYP24 as well as mutations in APC distal to codon 850 were strongly associated with Gardners syndrome in a cohort of 457 FAP patients, This work suggests that alterations in the vitamin D/VDR axis are important in Gardner's syndrome, as well as in the etiology of anal cancer.
Project description:Vitamin D deficiency is associated with increased incidence and severity of various immune-mediated diseases. Active vitamin D (1?,25-dihydroxyvitamin D3; 1,25(OH)2 D3) up-regulates CD4(+) T-cell expression of the purine ectonucleotidase CD39, a molecule that is associated with the generation of anti-inflammatory adenosine. Here we aimed to investigate the direct impact of 1,25(OH)2 D3 on expression of the downstream ecto-5'-nucleotidase CD73 by human CD4 T cells, and components of the transforming growth factor-? (TGF-?) pathway, which have been implicated in the modulation of CD73 by murine T cells. At 10(-8) to 10(-7) m, 1,25(OH)2 D3 significantly increased expression of CD73 on peripheral human CD4(+) T cells. Although 1,25(OH)2 D3 did not affect the mRNA expression of latent TGF-?1 , 1,25(OH)2 D3 did up-regulate expression of TGF-?-associated molecules [latency-associated peptide (LAP), glycophorin A repetitions predominant (GARP), GP96, neuropilin-1, thrombospondin-1 and ?v integrin] which is likely to have contributed to the observed enhancement in TGF-? bioactivity. CD73 was highly co-expressed with LAP and GARP following 1,25(OH)2 D3 treatment, but unexpectedly, each of these cell surface molecules was expressed primarily on CD4(+) Foxp3(-) T cells, rather than CD4(+) Foxp3(+) T cells. Notably, neutralization of TGF-? significantly impaired 1,25(OH)2 D3-mediated induction of CD73. Collectively, we show that 1,25(OH)2 D3 enhances expression of CD73 on CD4(+) Foxp3(-) T cells in a process that is at least partially TGF-?-dependent. These data reveal an additional contributing mechanism by which vitamin D may be protective in immune-mediated disease.
Project description:Background:Curcumin contained in Curcuma xanthorrhiza is an immunomodulator that has similar biological effect as vitamin D. Combination of curcumin and vitamin D3 is expected to work synergistically. Objective:To determine the effect of Curcuma xanthorrhiza supplementation on vitamin D3 administration to SLEDAI, IL-6, and TGF-?1 serum in SLE patients with hypovitamin D. Methods:This was a double-blind RCT conducted in Saiful Anwar Hospital, Malang, in January 2016-March 2017. Subjects were SLE active (SLEDAI > 3) with levels of 25(OH)D3 ? 30?ng/ml and divided into two groups: those receiving cholecalciferol 3 × 400?IU and placebo 3 × 1 tablets (group I) and those receiving 3 × 400?IU cholecalciferol and Curcuma xanthorrhiza 3 × 20?mg for 3 months (group II). SLEDAI, levels of vitamin D, IL-6, and TGF-?1 in serum were evaluated before and after the treatment. Results:There were no significant differences in SLEDAI reduction, decreased serum levels of IL-6, and increased levels of TGF-?1 serum among groups after the treatment. Decreased levels of serum IL-6 have a positive correlation with SLEDAI reduction. Conclusion. Curcuma xanthorrhiza supplementation on vitamin D3 had no effects on SLEDAI and serum levels of IL-6 and TGF-?1. This clinical trial is registered with NCT03155477.
Project description:AIM:To prospectively evaluate the effects of vitamin D3 on disease activity and quality of life in ulcerative colitis (UC) patients with hypovitaminosis D. METHODS:The study was a prospective double-blinded, randomized trial conducted at Community Regional Medical Center, Fresno, CA from 2012-2013. Patients with UC and a serum 25(OH)D level <30 ng/ml were eligible for the study. Enrolled subjects were randomized to receive either 2,000 IU or 4,000 IU of oral vitamin D3 daily for a total of 90 days. The Short IBD Questionnaire (SIBDQ) for quality of life, the Partial Mayo Score for UC disease activity and serum lab tests were compared between the two treatment groups. Matched pair t-tests were computed to assess differences between the vitamin D levels, CRP, UC disease activity and SIBDQ scores before and after vitamin D3 therapy using SPSS version 21. RESULTS:Eight UC patients received 2,000 IU/daily and ten UC patients received 4,000 IU/daily of vitamin D3 for 90 days. Vitamin D levels increased after 90 days of oral vitamin D3 in both dose groups. However, the increase in vitamin D levels after 90 days of oral vitamin D3, in the 4,000 IU group was significantly higher 16.80 ± 9.15 (p < 0.001) compared to the 2,000 IU group of vitamin D 5.00 ± 3.12 (p = 0.008). Normal vitamin D levels (>30 ng/dl) were achieved in four out of the ten UC patients (40%) in the 4,000 IU group and in one out of the eight UC patients (12%) in the 2,000 IU group. In the group receiving 4,000 IU/day of vitamin D3 the increase in quality life scores (SIBDQ) was significant 1.0 ± 1.0 (p = 0.017) but not in the 2,000 IU vitamin D3 group 0.1 ± 1.0 (p = 0.87). In the 2,000 IU of vitamin D3 group the mean decrease in the Partial Mayo UC Score was -0.5 ± 1.5 (p = 0.38) compared to -1.3 ± 2.9 (p = 0.19) in the 4,000 IU vitamin D3 group but this was not statistically significant. CRP levels decreased after 90 days of daily vitamin D3 in both the 2,000 IU group and 4,000 IU group by -3.0 ± 9.4 (p = 0.4) and -10.8 ± 35.0 (p = 0.36) respectively. CONCLUSION:Vitamin D3 at 4,000 IU/day is more effective than 2,000 IU/day in increasing vitamin D to sufficient levels in UC patients with hypovitaminosis D, however higher doses or treatment beyond ninety days may be required. Vitamin D3 may improve the quality of life in UC patients but clinically significant improvement is not yet established. The effect of vitamin D3 on UC disease activity is still unclear. Further larger studies are needed to investigate the effects of vitamin D in ulcerative colitis.
Project description:Pulmonary fibrosis is a progressive fibrotic lung disease of persisting lung injury and ineffective wound repair, with poor prognosis. Epithelial-mesenchymal transition (EMT) of alveolar epithelia cells is an early event in the development of pulmonary fibrosis, and transforming growth factor β (TGF-β) is an acknowledged inducer of EMT. Epidemiological studies demonstrated that serum levels of 25-hydroxy-vitamin D were associated with the presence of fibrosis diseases. We investigated whether vitamin D attenuated TGF-β-induced pro-fibrotic effects through inhibiting EMT in human alveolar epithelia A549 cells. A549 cells were cultured with TGF-β alone or in combination with 1α,25-dihydroxyvitamin D3 (1α,25(OH)₂D₃). TGF-β increased the expression of the mesenchymal markers (N-cadherin and Vimentin), and decreased the expression of epithelial markers (E-cadherin). 1α,25(OH)₂D₃ attenuated these TGF-β-induced alterations. Furthermore, the EMT-related transcription factors (Snail and β-catenin) and the extracellular matrix genes (Collagen I and fibronectin) were inhibited by 1α,25(OH)₂D₃, while the expression of vitamin D receptor (VDR) was elevated. In addition, 1α,25(OH)₂D₃ alleviated the cell migration and the invasion abilities in TGF-β-stimulated A549 cells, determined by the scratch wound healing and transwell assays. Our findings suggested that 1α,25(OH)₂D₃ inhibited the pro-fibrotic phenotype of lung epithelial cells under TGF-β stimulation and provided new clues in the clinical management of pulmonary fibrosis.