AbstractGut barrier dysfunction promotes chronic inflammation, contributing to several gastrointestinal diseases, including colorectal cancer. Preliminary evidence suggests that vitamin D and calcium could prevent colorectal carcinogenesis, in part, by influencing gut barrier function. However, relevant human data are scarce. We tested the effects of supplemental calcium (1,200 mg/day) and/or vitamin D3 (1,000 IU/day) on circulating concentrations of biomarkers of gut permeability (anti-flagellin and anti-lipopolysaccharide IgA and IgG, measured via ELISA) from baseline to 1 and 3 or 5 years postbaseline among 175 patients with colorectal adenoma in a randomized, double-blinded, placebo-controlled clinical trial. We also assessed factors associated with baseline concentrations of these biomarkers. We found no appreciable effects of supplemental vitamin D3 and/or calcium on individual or aggregate biomarkers of gut permeability. At baseline, a combined permeability score (the summed concentrations of all four biomarkers) was 14% lower among women (P = 0.01) and 10% higher among those who consumed >1 serving per day of red or processed meats relative to those who consumed none (Ptrend = 0.03). The permeability score was estimated to be 49% higher among participants with a body mass index (BMI) > 35 kg/m2 relative to those with a BMI < 22.5 kg/m2 (Ptrend = 0.17). Our results suggest that daily supplemental vitamin D3 and/or calcium may not modify circulating concentrations of gut permeability biomarkers within 1 or 3–5 years, but support continued investigation of modifiable factors, such as diet and excess adiposity, that could affect gut permeability.Prevention Relevance:Calcium and vitamin D may be involved in regulating and maintaining the integrity of the intestinal mucosal barrier, the dysfunction of which results in exposure of the host to luminal bacteria, endotoxins, and antigens leading to potentially cancer-promoting endotoxemia and chronic colon inflammation. While our results suggest that daily supplementation with these chemopreventive agents does not modify circulating concentrations of gut permeability biomarkers, they support continued investigation of other potential modifiable factors, such as diet and excess adiposity, that could alter gut barrier function, to inform the development of treatable biomarkers of risk for colorectal neoplasms and effective colon cancer preventive strategies.

Table S1. pIKKα/β, TLR4, and TLR5 Expression in the Full Length of Crypts and Stroma in the Differentiation Zone (Upper 40%) in the Normal-Appearing Rectal Mucosa of the Adjunct Biomarker Study Table S2. pIKKα/β, TLR4, and TLR5 Expression in the Full Length of Crypts and Stroma in the Proliferation Zone (Lower 60%) of Normal-Appearing Rectal Mucosa of the Adjunct Biomarker Study Participants (n = 105) During the Triala. Table S3. pIKKα/β, TLR4, and TLR5 Expression in the Ratio (ϕh) of the Differentiation Zone over the Full Length of the Crypt in Normal-Appearing Rectal Mucosa of the Adjunct Biomarker Study Participants (n = 105) During the Triala. Table S4. The Ratios of (pIKKα/β)/TLR4 and (pIKKα/β)/TLR5 in the Crypts in the Normal-Appearing Rectal Mucosa of the Adjunct Biomarker Study Participants (n=105)a. Table S5. Geometric Means, 95% CIs, and Proportional Differences in pIKKα/β, TLR4 and TLR5 Expression in the Full Length of the Crypts and Stroma, by Categories of Baseline Participant Characteristics (n = 105)a.

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Perspective on this Article from Effects of Vitamin D and Calcium Supplementation on Markers of Apoptosis in Normal Colon Mucosa: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Supplementary Figure Legends 1-4 from A Randomized Clinical Trial of the Effects of Supplemental Calcium and Vitamin D3 on Markers of Their Metabolism in Normal Mucosa of Colorectal Adenoma Patients

Supplementary References from A Randomized Clinical Trial of the Effects of Supplemental Calcium and Vitamin D3 on Markers of Their Metabolism in Normal Mucosa of Colorectal Adenoma Patients

Abnormal expression of Wnt pathway and DNA mismatch repair proteins is common during colorectal carcinogenesis. To investigate cross-sectional associations of lifestyle, dietary, and other participant characteristics with the expression of such proteins, we measured APC, β-catenin, E-cadherin, and MSH2 colorectal crypt expression in biopsies of normal-appearing colorectal mucosa from 104 sporadic colorectal adenoma patients using automated immunohistochemistry and quantitative image analysis. We used multivariable general linear models to compare adjusted mean biomarker expression across categories of participant characteristics. Example findings include that among women relative to men, mean APC expression in whole crypts, the upper 40% of crypts (differentiation zone), and the lower 60% of crypts (proliferation zone) was 322.9% higher (p<0.01), 296.7% higher (p<0.01), and 399.1% higher (p<0.01), respectively. Among participants with higher alcohol consumption, APC expression in the crypt differentiation zone was estimated to be 15.9% lower (p=0.08). Among those with higher total meat consumption, β-catenin expression in whole crypts and the crypt proliferation zone was estimated to be 20.5% higher (p=0.07) and 19.6% higher (p=0.06), respectively, and MSH2 expression in the crypt differentiation zone was estimated to be 64.4% lower (p=0.10). Among those with a higher body mass index, MSH2 expression in the crypt differentiation zone was estimated to be 87.5% lower (p=0.15). These pilot study findings suggest that being male, higher adiposity, and higher alcohol and meat consumption may be unfavorably associated with biomarkers of colorectal carcinogenesis pathway proteins in the normal-appearing colorectal mucosa of sporadic colorectal adenoma patients and support further investigation in larger studies.

Increased COX-2 and decreased 15-hydroxyprostaglandin dehydrogenase (15-HPGD) expression promote prostaglandin-mediated inflammation and colorectal carcinogenesis. Experimental studies suggest that vitamin D and calcium may inhibit these pathways, but their effects on colorectal tissue COX-2 and 15-HPGD expression in humans are unknown. We tested the effects of supplemental vitamin D(1,000 IU/day) and/or calcium (1,200 mg/day) on COX-2 and 15-HPGD expression in the morphologically normal rectal mucosa from 62 paients with colorectal adenoma in a placebo-controlled chemoprevention trial. We measured biomarker expression using automated IHC and quantitative image analysis at baseline and 1-year follow-up, and assessed treatment effects using mixed linear models. The primary outcome was the COX-2/15-HPGD expression ratio, because these enzymes function as physiologic antagonists. After 1 year of treatment, the mean COX-2/15-HPGD expression ratio in full-length crypts proportionately decreased 47% in the vitamin D group (P = 0.001), 46% in the calciumgroup (P = 0.002), and 34% in the calcium thorn vitamin D group (P = 0.03), relative to the placebo group. Among individuals with the functional vitamin D-binding protein isoform DBP2 (GC rs4588*A), the COX-2/15-HPDG ratio decreased 70% (P = 0.0006), 75% (P = 0.0002), and 60% (P = 0.006) in the vitamin D, calcium, and combined supplementation groups, respectively, relative to placebo. These results show that vitamin D and calcium favorably modulate the balance of expression of COX-2 and 15-HPGD-biomarkers of inflammation that are strongly linked to colorectal carcinogenesis-in the normal-appearing colorectal mucosa of patients with colorectal adenoma (perhaps especially those with the DBP2 isoform). Prevention Relevance: Supplemental calcium and vitamin D reduce indicators of cancer-promoting inflammation in normal colorectal tissue in humans, thus furthering our understanding of how they may help prevent colorectal cancer.

The physical gut barrier, comprised of a thick mucus layer and the epithelium, plays an important role in defense against microbes and foreign antigens. Calcium and vitamin D may be involved in maintaining the integrity of the intestinal mucosal barrier, the dysfunction of which may lead to endotoxemia and inflammation, and contribute to colorectal carcinogenesis. We investigated supplemental calcium (1200 mg, daily) and/or vitamin D-3 (1000 IU daily) effects on intestinal barrier function-related biomarkers in a subset of 105 participants from a large colorectal adenoma recurrence chemoprevention clinical trial. We assessed expression of the tight junction proteins claudin-1 (CLDN1), occludin (OCLD), and mucin-12 (MUC12) in the normal-appearing colorectal mucosa using standardized, automated immunohistochemistry and quantitative image analysis. Following 1 year of treatment, in the calcium relative to the no calcium group, the CLDN1, OCLD, and MUC12 expression increased by 14% (P = 0.17), 23% (P = 0.11), and 22% (P = 0.07), respectively. In secondary analyses, the estimated calcium treatment effects were greater among participants with baseline serum 25-OH-vitamin D concentrations below the median value of 22.69 ng/mL (CLDN1: 29%, P = 0.04; OCLD: 36%, P = 0.06; MUC12: 35%, P = 0.05). There were no biomarker expression changes in the vitamin D-3 alone group; however, modest increases were found in the combined calcium/vitamin D-3 group. At baseline, obesity, history of a sessile-serrated adenoma, colorectal MIB-1/Ki-67 expression, and a family history of colorectal cancer were associated with CLDN1, OCLD, and MUC12 expression. Our study supports continued investigation of factors that could affect intestinal mucosal barrier integrity relevant to colorectal carcinogenesis.

To clarify the roles of vitamin D and calcium as potential chemopreventive agents against colorectal cancer in humans, and to develop “treatable”, pre-neoplastic, phenotypic biomarkers of risk for colorectal neoplasms, we estimated the effects of supplemental vitamin D3 (1,000 IU/day [25 μg/day]) and calcium (1,200 mg/day), alone and in combination, on biomarkers of proliferation (mib-1), differentiation (p21), and apoptosis (bax [apoptosis-promoting] and bcl-2 [apoptosis-inhibiting]), in the normal-appearing rectal mucosa in a subsample of participants (n = 104) in a larger randomized, double-blind, placebo-controlled clinical trial among colorectal adenoma patients. The biomarkers were measured in rectal biopsies at baseline and after one year of follow up, using automated immunohistochemistry and quantitative image analysis. In the vitamin D plus calcium group relative to control, in the crypt differentiation zone (upper 40% of crypts), mib-1 expression decreased 24% (P = 0.28); p21 expression alone and relative to mib-1 expression increased 29% (P = 0.06) and 73% (P = 0.06), respectively; and bax expression relative to mib-1 expression increased 58% (P = 0.21). The estimated vitamin D alone treatment effects were similar but of lesser magnitudes, and those for calcium alone were mixed. All estimated treatment effects on bcl-2 expression were close to the null. These pilot study results support further investigation of whether 1) vitamin D and calcium promote colorectal epithelial cell differentiation, reduce proliferation, and promote apoptosis in the normal-appearing human colorectal mucosa, 2) vitamin D and calcium act as chemopreventive agents against colorectal neoplasms, and 3) mib-1, p21, and bax are potential “treatable”, pre-neoplastic, biomarkers of risk for colorectal neoplasms.

Abnormal expression of the DNA mismatch repair protein MSH2 and autocrine/paracrine transforming growth factors TGF alpha (growth promoter) and TGF beta(1) (growth inhibitor) is common during colorectal carcinogenesis. To estimate vitamin D and calcium effects on these biomarkers in the normal-appearing colorectal mucosa of sporadic colorectal adenoma patients, we conducted a pilot, randomized, double-blinded, placebo-controlled, modified 2 x 2 factorial chemoprevention clinical trial (N = 104) of supplemental vitamin D-3 (1000 IU daily) and calcium (1200 mg daily), alone and in combination, versus placebo over 1 year. The expression of the three biomarkers and Ki-67/mib-1 in colorectal crypts in biopsies of normal-appearing rectal mucosa were detected using automated immunohistochemistry and quantified using image analysis. In the vitamin D-3 and vitamin D-3 plus calcium groups, relative to their reference groups, in the upper 40% (differentiation zone) of crypts, it was estimated that, respectively, the MSH2/mib-1 ratio increased by 47% (P = 0.14) and 62% (P = 0.08), TGF beta(1) expression increased by 41% (P = 0.25) and 78% (P = 0.14), and the TGF alpha/TGF beta(1) ratio decreased by 25% (P = 0.31) and 44% (P = 0.13). Although not statistically significant, these results support further research into (i) whether supplemental vitamin D-3, alone or in combination with calcium, may increase DNA mismatch repair relative to proliferation, increase TGF beta(1) expression, and decrease autocrine/paracrine growth promotion relative to growth inhibition in the colorectal epithelium, all hypothesized to reduce risk for colorectal carcinogenesis; and (ii) the expression of MSH2 relative to mib-1, TGF beta(1) alone, and TGF alpha relative to TGF beta(1) in the normal-appearing rectal mucosa as potential modifiable, pre-neoplastic markers of risk for colorectal neoplasms.

Abstract Chronic inflammation in the colorectum, a significant contributor to colorectal carcinogenesis, can be triggered by the activation of proinflammatory signaling pathways such as those initiated by Toll-like receptors (TLR) and nuclear factor κB (NF-κB). Although experimental evidence supports calcium and vitamin D potentially modifying these proinflammatory pathways in the colorectum, human data in these regards are scarce. We investigated supplemental calcium (1,200 mg daily) and/or vitamin D3 (1,000 IU daily) effects on inflammatory signaling pathway-related biomarkers in a subset of 105 participants from a colorectal adenoma recurrence chemoprevention clinical trial. We assessed expression of TLR4 and TLR5, which recognize the bacterial components lipopolysaccharides and flagellin, respectively, and phospho-IKKα/β (pIKKα/β), a biomarker of inflammation, in the normal-appearing rectal crypt epithelium and stroma using standardized, automated immunohistochemistry and quantitative image analysis. Following 1 year of treatment, TLR4, TLR5, and pIKKα/β expression in the rectal mucosa did not statistically significantly change with vitamin D or calcium supplementation, taken alone or in combination. Several baseline participant characteristics, including body mass index, history of sessile serrated adenomas, high red/processed meat intake, and high levels of rectal epithelial cell proliferation (as measured by MIB-1/Ki-67), were associated with higher baseline expression of TLRs or pIKKα/β. Our findings suggest that vitamin D and calcium may have no substantial effect on the investigated biomarkers. However, several modifiable lifestyle factors may be associated with TLRs and pIKKα/β expression in the normal rectal mucosa, supporting their future investigation as potentially treatable, preneoplastic risk factors for colorectal neoplasms. Cancer Prev Res; 11(11); 707–16. ©2018 AACR.

APC/β‐catenin pathway malfunction is a common and early event in colorectal carcinogenesis. To assess calcium and vitamin D effects on the APC/β‐catenin pathway in the normal‐appearing colorectal mucosa of sporadic colorectal adenoma patients, nested within a larger randomized, double‐blind, placebo‐controlled, partial 2 × 2 factorial chemoprevention clinical trial of supplemental calcium (1200 mg daily) and vitamin D (1000 IU daily), alone and in combination versus placebo, we assessed APC, β‐catenin, and E‐cadherin expression in colon crypts in normal‐appearing rectal mucosa biopsies from 104 participants at baseline and 1‐yr follow up using standardized, automated immunohistochemistry and quantitative image analysis. For vitamin D versus no vitamin D, the ratio of APC expression to β‐catenin expression in the upper 40% (differentiation zone) of crypts (APC/β‐catenin score) increased by 28% (P = 0.02), for calcium versus no calcium it increased by 1% (P = 0.88), and for vitamin D + calcium versus calcium by 35% (P = 0.01). Total E‐cadherin expression increased by 7% (P = 0.35) for vitamin D versus no vitamin D, 8% (P = 0.31) for calcium versus no calcium, and 12% (P = 0.21) for vitamin D + calcium versus calcium. These results support (i) that vitamin D, alone or in combination with calcium, may modify APC, β‐catenin, and E‐cadherin expression in humans in directions hypothesized to reduce risk for colorectal neoplasms; (ii) vitamin D as a potential chemopreventive agent against colorectal neoplasms; and (iii) the potential of APC, β‐catenin, and E‐cadherin expression as treatable, pre‐neoplastic risk biomarkers for colorectal neoplasms. © 2016 Wiley Periodicals, Inc.

Transforming growth factor alpha (TGF alpha) and TGF beta(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 D-3 on these two markers in the normal-appearing colorectal mucosa in humans are unknown. We conducted a pilot, randomized, double-blind, placebo-controlled, 2 x 2 factorial clinical trial (n = 92; 23/treatment group) of calcium 2 g and/or vitamin D-3 800 IU/d versus placebo over 6 mo. TGF alpha and TGF beta(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 D-3, and calcium plus vitamin D-3 groups relative to the placebo group (1) the mean overall expression of TGF beta(1) increased by 14% (P = 0.25), 19% (P = 0.17), and 22% (P = 0.09); (2) the ratio of TGF alpha 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 alpha/TGF beta(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 D-3 may increase TGF beta(1) expression and shift TGF alpha 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. (C) 2013 Wiley Periodicals, Inc.

Increased inflammatory markers predict antidepressant treatment non-response in patients with depression, and inflammatory cytokines can sabotage and circumvent mechanisms of action of conventional antidepressants. We therefore endeavored to determine whether inhibition of the inflammatory cytokine tumor necrosis factor (TNF)-alpha would reduce depressive symptoms in patients with treatment resistant depression (TRD) and whether baseline inflammation would predict response. Sixty outpatients with major depression participated in a double-blind, placebo-controlled trial involving random assignment to three infusions of the TNF-alpha antagonist infliximab (5 mg/kg) (n = 30) or placebo (n = 30) at baseline and weeks 2 and 6 of a 12-week trial. The 17-item Hamilton Depression Rating Scale (HAM-D-17) was the primary outcome variable. No differences in change of HAM-D-17 scores between groups across time were found. Interestingly, however, there was significant interaction between treatment, time and log baseline hs-CRP (p = 0.01) with the change in HAM-D-17 scores at Week 12 favoring infliximab-treated patients at a baseline hs-CRP > 5 mg/L. Treatment response (⩾50% reduction in HAM-D-17 at any time during treatment) in patients with a baseline hs-CRP > 5 mg/L (n = 22) was 62% in infliximab-treated patients versus 33% for placebo. Baseline concentrations of TNF-alpha and its soluble receptors were significantly higher in infliximab-treated responders versus infliximab non-responders (p < 0.05). Drop-outs and adverse events did not differ between groups. This proof-of-concept study suggests that anti-cytokine therapies may have efficacy in TRD patients, but only in the context of high inflammation.

CONTEXT Increased concentrations of inflammatory biomarkers predict antidepressant nonresponse, and inflammatory cytokines can sabotage and circumvent the mechanisms of action of conventional antidepressants. OBJECTIVES To determine whether inhibition of the inflammatory cytokine tumor necrosis factor (TNF) reduces depressive symptoms in patients with treatment-resistant depression and whether an increase in baseline plasma inflammatory biomarkers, including high-sensitivity C-reactive protein (hs-CRP), TNF, and its soluble receptors, predicts treatment response. DESIGN Double-blind, placebo-controlled, randomized clinical trial. SETTING Outpatient infusion center at Emory University in Atlanta, Georgia. PARTICIPANTS A total of 60 medically stable outpatients with major depression who were either on a consistent antidepressant regimen (n = 37) or medication-free (n = 23) for 4 weeks or more and who were moderately resistant to treatment as determined by the Massachusetts General Hospital Staging method. INTERVENTIONS Three infusions of the TNF antagonist infliximab (5 mg/kg) (n = 30) or placebo (n = 30) at baseline and weeks 2 and 6 of a 12-week trial. MAIN OUTCOME MEASURES The 17-item Hamilton Scale for Depression (HAM-D) scores. RESULTS No overall difference in change of HAM-D scores between treatment groups across time was found. However, there was a significant interaction between treatment, time, and log baseline hs-CRP concentration (P = .01), with change in HAM-D scores (baseline to week 12) favoring infliximab-treated patients at a baseline hs-CRP concentration greater than 5 mg/L and favoring placebo-treated patients at a baseline hs-CRP concentration of 5 mg/L or less. Exploratory analyses focusing on patients with a baseline hs-CRP concentration greater than 5 mg/L revealed a treatment response (≥50% reduction in HAM-D score at any point during treatment) of 62% (8 of 13 patients) in infliximab-treated patients vs 33% (3 of 9 patients) in placebo-treated patients (P = .19). Baseline concentrations of TNF and its soluble receptors were significantly higher in infliximab-treated responders vs nonresponders (P < .05), and infliximab-treated responders exhibited significantly greater decreases in hs-CRP from baseline to week 12 compared with placebo-treated responders (P < .01). Dropouts and adverse events were limited and did not differ between groups. CONCLUSIONS This proof-of-concept study suggests that TNF antagonism does not have generalized efficacy in treatment-resistant depression but may improve depressive symptoms in patients with high baseline inflammatory biomarkers. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00463580.

AbstractAPC/β-catenin pathway perturbation is a common early event in colorectal carcinogenesis and is affected by calcium and vitamin D in basic science studies. To assess the effects of calcium and vitamin D on adenomatous polyposis coli (APC), β-catenin, and E-cadherin expression in the normal appearing colorectal mucosa of sporadic colorectal adenoma patients, we conducted a randomized, double-blinded, placebo-controlled 2 × 2 factorial clinical trial. Pathology-confirmed colorectal adenoma cases were treated with 2 g/day elemental calcium and/or 800 IU/day vitamin D3 versus placebo over 6 months (N = 92; 23/group). Overall APC, β-catenin, and E-cadherin expression and distributions in colon crypts in normal-appearing rectal mucosa biopsies were detected by standardized automated immunohistochemistry and quantified by image analysis. In the vitamin D3-supplemented group relative to placebo, the proportion of APC in the upper 40% of crypts (Φh APC) increased 21% (P = 0.01), β-catenin decreased 12% (P = 0.18), E-cadherin increased 72% (P = 0.03), and the Φh APC/β-catenin ratio (APC/β-catenin score) increased 31% (P = 0.02). In the calcium-supplemented group Φh APC increased 10% (P = 0.12), β-catenin decreased 15% (P = 0.08), and the APC/β-catenin score increased 41% (P = 0.01). In the calcium/vitamin D3-supplemented group, β-catenin decreased 11% (P = 0.20), E-cadherin increased 51% (P = 0.08), and the APC/β-catenin score increased 16% (P = 0.26). These results support (i) that calcium and vitamin D modify APC, β-catenin, and E-cadherin expression in humans in directions hypothesized to reduce risk for colorectal neoplasms, (ii) calcium and vitamin D as potential chemopreventive agents against colorectal neoplasms, and (iii) the potential of APC, β-catenin, and E-cadherin expression as modifiable, preneoplastic risk biomarkers for colorectal neoplasms. Cancer Prev Res; 5(10); 1247–56. ©2012 AACR.

AbstractIn cancer cell lines and rodent models, calcium and vitamin D favorably modulate cell proliferation, differentiation, and apoptosis in colonic epithelia. These effects may be modulated by local expression of the calcium receptor (CaR), the vitamin D receptor (VDR), and the P450 cytochromes, CYP27B1 and CYP24A1; however, they have yet to be investigated in humans. To address this gap, we conducted a randomized, double-blinded, placebo-controlled 2 × 2 factorial clinical trial. Patients with at least one pathology-confirmed colorectal adenoma were treated with 2 g/d elemental calcium and/or 800 IU/d vitamin D3 versus placebo over 6 months (n = 92; 23 per group). CaR, VDR, CYP27B1, and CYP24A1 expression and distribution in biopsies of normal appearing rectal mucosa were detected by standardized, automated immunohistochemistry and quantified by image analysis. In the calcium-supplemented group, CaR expression increased 27% (P = 0.03) and CYP24A1 expression decreased 21% (P = 0.79). In the vitamin D3-supplemented group, CaR expression increased 39% (P = 0.01) and CYP27B1 expression increased 159% (P = 0.06). In patients supplemented with both calcium and vitamin D3, VDR expression increased 19% (P = 0.13) and CaR expression increased 24% (P = 0.05). These results provide mechanistic support for further investigation of calcium and vitamin D3 as chemopreventive agents against colorectal neoplasms, and CaR, VDR, CYP27B1, and CYP24A1 as modifiable, preneoplastic risk biomarkers for colorectal neoplasms. Cancer Res; 71(2); 413–23. ©2010 AACR.

An 83-year-old Asian man presented with a 3-day history of melena. His medical history was significant for hypertension and coronary artery disease. On physical examination, he was afebrile with normal vital signs. His abdomen was soft and nontender. Laboratory data showed a hemoglobin level of 12.8 g/dL from a baseline level of 15.6 g/dL. On upper endoscopy, a large, friable, ulcerated mass was found in the second part of the duodenum (Figure A). The mass could not be traversed with the endoscope.

To further clarify and develop calcium and vitamin D as chemopreventive agents against colorectal cancer in humans and develop modifiable biomarkers of risk for colorectal cancer, we conducted a pilot, randomized, double-blind, placebo-controlled, 2 × 2 factorial clinical trial to test the effects of calcium and vitamin D3, alone and in combination, on key DNA mismatch repair proteins in the normal colorectal mucosa. Ninety-two men and women with at least one pathology-confirmed colorectal adenoma were treated with 2.0 g/d calcium or 800 IU/d vitamin D3, alone or in combination, versus placebo over 6 months. Colorectal crypt overall expression and distribution of MSH2 and MLH1 proteins in biopsies of normal-appearing rectal mucosa were detected by automated immunohistochemistry and quantified by image analysis. After 6 months of treatment, MSH2 expression along the full lengths of crypts increased by 61% (P = 0.11) and 30% (P = 0.36) in the vitamin D and calcium groups, respectively, relative to the placebo group. The estimated calcium and vitamin D treatment effects were more pronounced in the upper 40% of crypts (differentiation zone) in which MSH2 expression increased by 169% (P = 0.04) and 107% (P = 0.13) in the vitamin D and calcium groups, respectively. These findings suggest that higher calcium and vitamin D intakes may result in increased DNA MMR system activity in the normal colorectal mucosa of sporadic adenoma patients and that the strongest effects may be vitamin D related and in the differentiation zone of the colorectal crypt. Cancer Epidemiol Biomarkers Prev; 19(4); 1022–32. ©2010 AACR.