Low circulating 25-hydroxyvitamin D level is associated with increased colorectal cancer mortality: a systematic review and dose-response meta-analysis

Umbrella Review on the Relationship between Vitamin D Levels and Cancer

BACKGROUND

Cancer is a growing public health problem and cancer is linked to vitamin D via several mechanisms. Recent umbrella reviews on the extra-skeletal effects of vitamin D did not turn their attention to cancer. Accordingly, an overview of the current state of research is needed.

MATERIALS AND METHODS

An umbrella review was conducted to provide an overview of systematic reviews on the association between vitamin D and incidence or mortality of breast cancer, colorectal cancer, lung cancer, pancreatic cancer, and prostate cancer.

RESULTS

Inverse correlations were found between the vitamin D level (measured by circulating 25(OH)D) and mortality for all five types of cancer. For breast cancer, colorectal cancer, lung cancer, and pancreatic cancer, there are also hints of a lower incidence due to higher 25(OH)D levels.

CONCLUSION

As most reviews include observational studies, conclusions on causality cannot be made. Methodological differences between the included reviews and different study designs in the individual studies lead to methodological problems. Despite these problems, the review shows inverse correlations between 25(OH)D levels and mortality, and mostly inverse correlations between 25(OH)D levels and incidence.

Post-diagnosis dietary factors, supplement use and colorectal cancer prognosis: A Global Cancer Update Programme (CUP Global) systematic literature review and meta-analysis

The role of diet in colorectal cancer prognosis is not well understood and specific lifestyle recommendations are lacking. We searched for randomised controlled trials (RCTs) and longitudinal observational studies on post-diagnosis dietary factors, supplement use and colorectal cancer survival outcomes in PubMed and Embase from inception until 28th February 2022. Random-effects dose-response meta-analyses were conducted when at least three studies had sufficient information. The evidence was interpreted and graded by the CUP Global independent Expert Committee on Cancer Survivorship and Expert Panel. Five RCTs and 35 observational studies were included (30,242 cases, over 8700 all-cause and 2100 colorectal cancer deaths, 3700 progression, recurrence, or disease-free events). Meta-analyses, including 3-10 observational studies each, were conducted for: whole grains, nuts/peanuts, red and processed meat, dairy products, sugary drinks, artificially sweetened beverages, coffee, alcohol, dietary glycaemic load/index, insulin load/index, marine omega-3 polyunsaturated fatty acids, supplemental calcium, circulating 25-hydroxyvitamin D (25[OH]D) and all-cause mortality; for alcohol, supplemental calcium, circulating 25(OH)D and colorectal cancer-specific mortality; and for circulating 25(OH)D and recurrence/disease-free survival. The overall evidence was graded as 'limited'. The inverse associations between healthy dietary and/or lifestyle patterns (including diets that comprised plant-based foods), whole grains, total, caffeinated, or decaffeinated coffee and all-cause mortality and the positive associations between unhealthy dietary patterns, sugary drinks and all-cause mortality provided 'limited-suggestive' evidence. All other exposure-outcome associations provided 'limited-no conclusion' evidence. Additional, well-conducted cohort studies and carefully designed RCTs are needed to develop specific lifestyle recommendations for colorectal cancer survivors.

Associations between diet and nutritional supplements and colorectal cancer: A systematic review

Background and Aim

Colorectal cancer (CRC) is one of the most prevalent cancers around the world. The link between nutrients and the likelihood of developing CRC remains uncertain. The primary objective of the present study was to investigate the potential connection between dietary intake/dietary supplements and the occurrence of CRC through a literature review.

Methods

A comprehensive online search was conducted in PubMed, Scopus, Web of Science, and the Cochrane Library from January 1990 to March 2023 using appropriate keywords. A systematic search was conducted for clinical trials and cohort studies in order to determine the relationship between dietary components/supplements and CRC.

Results

The intake of long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFAs), consisting of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has the potential to decrease the likelihood of developing CRC (eight studies found positive effects and four studies found no association). Some other dietary components such as probiotics, prebiotics, and synbiotics may contribute to suppressing CRC development (three studies found positive effects, whereas three studies did not find any association). There is inconclusive evidence that supplementation with certain micronutrients including vitamin D (one trial found positive effects and another trial reported no association), folate, zinc, and selenium may reduce the risk of CRC.

Conclusion

Some dietary supplements such as n-3 LCPUFAs and probiotics have the potential to reduce the risk of developing CRC. Further studies are necessary to validate these results and understand the underlying mechanisms.

Colorectal Cancer: Epidemiology, Risk Factors, and Prevention

Colorectal cancer (CRC) is the third most common cancer and the second most common cause of cancer mortality worldwide. There are disparities in the epidemiology of CRC across different populations, most probably due to differences in exposure to lifestyle and environmental factors related to CRC. Prevention is the most effective method for controlling CRC. Primary prevention includes determining and avoiding modifiable risk factors (e.g., alcohol consumption, smoking, and dietary factors) as well as increasing protective factors (e.g., physical activity, aspirin). Further studies, especially randomized, controlled trials, are needed to clarify the association between CRC incidence and exposure to different risk factors or protective factors. Detection and removal of precancerous colorectal lesions is also an effective strategy for controlling CRC. Multiple factors, both at the individual and community levels (e.g., patient preferences, availability of screening modalities, costs, benefits, and adverse events), should be taken into account in designing and implementing CRC screening programs. Health policymakers should consider the best decision in identifying the starting age and selection of the most effective screening strategies for the target population. This review aims to present updated evidence on the epidemiology, risk factors, and prevention of CRC.

Association between the Serum Vitamin D Concentration and All-Cause and Cancer-Specific Mortality in Individuals with Cancer

We aimed to explore the association between the serum 25-hydroxyvitamin D concentration and all-cause and cancer-specific mortality in 2,463 adult patients with cancer from the National Health and Nutrition Examination Survey 2007-2018. We linked mortality data from the survey to the National Death Index records up to December 31, 2019. During a median follow-up period of 70 months, 567 patients died, of whom 194 died due to cancer. Multivariate adjustment was performed for demographic characteristics, lifestyle, dietary factors, 25-hydroxyvitamin D testing period, and cancer site. Higher serum 25-hydroxyvitamin D concentrations up to 75 nmol/L significantly reduced the risk of all-cause and cancer-specific mortality. When 25-hydroxyvitamin D quartiles were compared, the multivariable-adjusted hazard ratios were 0.59 (95% confidence interval: 0.42, 0.84) for all-cause mortality (P for trend <0.001) and 0.48 (95% confidence interval: 0.29, 0.79) for cancer-specific mortality (P for trend = 0.037) in quartile 3 (79.3-99.2 nmol/L). A threshold of 75 nmol/L for serum 25-hydroxyvitamin D may represent an intervention target to reduce mortalities in patients with cancer, and maintaining 25(OH)D concentrations within range (79.3-99.2 nmol/L) is beneficial for reducing all-cause and cancer-specific mortality.

Pre- and post-diagnostic dairy intake in relation to recurrence and all-cause mortality in people with stage I-III colorectal cancer

PURPOSE

Higher dairy consumption is associated with a lower risk of colorectal cancer (CRC), but no studies thus far have investigated its relation with recurrence in CRC. Few studies have investigated total dairy in relation to mortality in CRC, and yielded inconsistent results.

METHODS

In this prospective cohort study, people newly diagnosed with stage I-III CRC filled out a food frequency questionnaire at diagnosis (n = 1812) and six months after diagnosis (n = 1672). We examined associations between pre- and post-diagnostic intake of total dairy, low-fat dairy, high-fat dairy, milk, yoghurt, and cheese with recurrence and all-cause mortality using multivariable Cox proportional hazard models and restricted cubic splines (RCS).

RESULTS

A total of 176 recurrences and 301 deaths occurred during a median follow-up of 3.0 and 5.9 years, respectively. Before diagnosis, a higher low-fat dairy intake was associated with a lower risk of recurrence (HRQ4vsQ1: 0.42, 95% CI 0.26-0.67; PRCS: 0.008) and all-cause mortality (HRQ4vsQ1: 0.58, 95% CI 0.41-0.81; PRCS < 0.001), whereas a higher high-fat dairy consumption tended to be associated with an increased all-cause mortality risk (HRQ4vsQ1: 1.41, 95% CI 0.98-2.01; PRCS: 0.030). After diagnosis, only the associations between low- and high-fat dairy in relation to all-cause mortality remained.

CONCLUSIONS

This study demonstrated that higher pre- and post-diagnostic intakes of low-fat dairy were associated with a reduced all-cause mortality risk in people with stage I-III CRC, whereas higher intakes of high-fat dairy were associated with an increased all-cause mortality risk. Also, a higher pre-diagnostic low-fat dairy intake was associated with a reduced risk of recurrence.

TRIAL REGISTRATION

Clinical Trials.gov identifier: NCT03191110.

[Calcium, Vitamin D, and Colorectal Cancer]

Colorectal cancer has a high incidence and mortality worldwide, with Westernized lifestyles and diet being significant contributing factors. Vitamin D and calcium have been known to reduce the incidence of colorectal cancer by affecting cell differentiation, proliferation, and apoptosis. Despite observational studies which have suggested that a higher serum vitamin D level can lower the risk of colorectal cancer and improve survival rates, no large-scale randomized controlled trials to establish these benefits have been conducted to date. Calcium intake has also been found to have a beneficial role in reducing the incidence and improving survival rates of colorectal cancer in several observational studies. Moreover, intervention studies have proved its effect in preventing colorectal adenomas. However, there are few intervention studies that have identified the relationship of vitamin D and calcium with colon cancer. To elucidate the impact of vitamin D and calcium supplementation on colorectal cancer, well-designed and large-scale randomized controlled trials are necessary in the future.

Prediagnostic 25-Hydroxyvitamin D in Association with Cancer-specific and All-cause Mortality among Low-income, Non-Hispanic Black Americans with Colorectal Cancer

BACKGROUND

Observational studies show high prediagnosis 25-hydroxyvitamin D is associated with lower mortality after colorectal cancer diagnosis. Results from clinical trials suggest vitamin D supplementation may improve outcomes among patients with colorectal cancer. Most studies included few Black Americans, who typically have lower 25-hydroxyvitamin D. We evaluated associations between serum 25-hydroxyvitamin D and mortality after colorectal cancer diagnosis among Black American cases.

METHODS

Data arose from 218 Black Americans from the Southern Community Cohort Study diagnosed with colorectal cancer during follow-up (age 40-79 at enrollment). Prediagnostic 25-hydroxyvitamin D was measured at enrollment and categorized as deficient (<12 ng/mL), insufficient (12-19.9 ng/mL), or sufficient (≥20 ng/mL). Mortality was determined from the National Death Index. Cox proportional hazards were used to estimate HRs and 95% confidence intervals (CI) for associations between 25-hydroxyvitamin D and mortality.

RESULTS

As a continuous exposure, higher 25-hydroxyvitamin D was associated with overall mortality [HR = 0.79 (0.65-0.96) per-SD increase, Ptrend = 0.02] and colorectal cancer-specific mortality [HR = 0.83 (0.64-1.08), Ptrend = 0.16]. For overall mortality, associations were strongest among females [HR = 0.65 (0.42-0.92)], current smokers [HR = 0.61 (0.38-0.98)], and obese participants [HR = 0.47 (0.29-0.77)]. Compared with those with deficiency, participants with sufficient 25-hydroxyvitamin D had lower overall mortality after multivariable adjustment [HR: 0.61 (0.37-1.01)].

CONCLUSIONS

Prediagnosis 25-hydroxyvitamin D is inversely associated with overall and colorectal cancer-specific mortality among Black Americans with colorectal cancer. Correcting vitamin D deficiency may improve survival of these patients, particularly for obese individuals and smokers.

IMPACT

Our results support including more Black Americans in trials of vitamin D supplementations to improve colorectal cancer outcomes.

Vitamin D Status, Cdx2 Genotype, and Colorectal Cancer Survival: Population-Based Patient Cohort

According to recent evidence, the prognostic value of Vitamin D (VitD) status for colorectal cancer (CRC) patients might be confined to patients with the GG genotype of Cdx2, a functional polymorphism of the VitD receptor gene. We aimed to validate these findings in a cohort of CRC patients. Post-operative serum 25-hydroxyvitamin D concentration was determined by mass spectrometry and Cdx2 genotyping was performed from blood or buccal swabs using standard methods. Joint associations of VitD status and Cdx2 with overall survival (OS), CRC-specific survival (CSS), recurrence-free survival (RFS), and disease-free survival (DFS) were assessed using Cox regression. For patients with GG genotype, adjusted hazard ratios (95% confidence interval) for the associations of sufficient compared with deficient VitD were 0.63 (0.50-0.78), 0.68 (0.50-0.90), 0.66 (0.51-0.86), and 0.62 (0.50-0.77) for OS, CSS, RFS, and DFS, respectively. These associations were weaker and not statistically significant for the AA/AG genotype. Interaction between VitD status and genotype did not reach statistical significance. VitD deficiency is an independent predictor of poorer survival, particularly for the GG Cdx2 carriers, suggesting a potential role of VitD supplementation according to VitD status and genotype, which should be evaluated in randomised trials.

Preoperative plasma vitamin D in patients with localized colorectal cancer: Age-dependent association with inflammation, postoperative complications, and survival

INTRODUCTION

Aging is often associated with low-grade chronic inflammation and a senescent immune system. Vitamin D is a regulator of immune function, and low plasma vitamin D is associated with poor health. The association between plasma vitamin D and inflammatory biomarkers and risk of postoperative complications and survival in patients with colorectal cancer (CRC) is unknown. Our aim was to investigate these associations and how they are influenced by age.

MATERIALS AND METHODS

Circulating vitamin D and the inflammatory biomarkers C-reactive protein (CRP), interleukin (IL)-6, and YKL-40 were measured in 398 patients with stage I-III CRC preoperatively. Older patients (≥70 years, n = 208) were compared to younger patients (<70 years, n = 190). The relation between vitamin D and complications and high inflammatory biomarker levels was presented by odds ratios ([OR], 95% confidence interval [CI]). Associations with survival were presented with hazard ratios ([HR], 95% CI).

RESULTS

Plasma vitamin D was higher in older patients than in younger patients (75 vs. 67 nmol/L, P = 0.001). High vitamin D was associated with low plasma CRP in younger patients (OR = 0.35, 95% CI 0.17-0.76), but not in older patients (OR = 0.93, 0.49-1.76). High vitamin D in older patients with CRC was associated with reduced risk of major complications (OR = 0.52, 0.28-0.95). This was not found in younger patients (OR = 1.47, 0.70-3.11). Deficient vitamin D (<25 nmol/L) was associated with short overall survival compared to sufficient (>50 nmol/L) irrespective of age (HR = 3.39, 1.27-9.37, P = 0.02).

CONCLUSION

For patients with localized CRC, high vitamin D levels before resection were associated with reduced risk of high inflammatory biomarkers for younger patients and reduced risk of major postoperative complications for older patients. Vitamin D deficiency was associated with reduced survival regardless of age.

Vitamin D and Colorectal Cancer: Current Perspectives and Future Directions

Vitamin D is considered to be the main mediator of the beneficial effects of sun exposure. In humans, highest expression of Vitamin D receptors is found in the intestinal tract. In addition, 1α,25-dihydroxyvitamin D3 (or calcitriol), the most active Vitamin D metabolite, plays important homeostatic roles in the intestine, particularly calcium absorption. Vitamin D deficiency is defined as a serum 25-hydroxyvitamin D [25(OH)D] level of < 20 ng/mL. Previous studies show that higher circulating 25(OH)D levels are associated with reduced risk of colorectal cancer (CRC) and improved survival. Most research to date has been conducted in animals, specifically mice. Although human studies have a limited number of participants, one study recruiting a large cohort of patients with advanced or metastatic CRC revealed that higher plasma 25(OH)D levels are associated with improved overall and progression-free survival. However, the effects of Vitamin D supplementation on incidence and mortality of CRC remain inconclusive. Although Vitamin D may help to prevent cancer, there is a paucity of research demonstrating conclusively that Vitamin D alters prognosis after chemotherapy. Here, we review the mechanisms by which Vitamin D affects CRC, as well as the results of clinical, epidemiological, and human intervention studies. We also discuss current perspectives and future directions regarding Vitamin D and CRC.

Nonlinear Association between Serum 25-Hydroxyvitamin D and All-Cause Mortality in Adults with Inflammatory Bowel Disease in a Prospective Cohort Study

BACKGROUND

Nonlinear association between serum 25-hydroxyvitamin D [25(OH)D] concentration and all-cause mortality has been widely reported for the general population, but this association has not been quantified for individuals with inflammatory bowel disease (IBD).

OBJECTIVES

The aim was to explore the association between serum 25(OH)D and all-cause mortality in individuals with IBD.

METHODS

We identified 2690 females and 2532 males aged 40-69 y with diagnosed IBD at baseline in the UK Biobank. Serum 25(OH)D concentration was measured by direct competitive chemiluminescent immunoassay. The outcome was all-cause mortality, ascertained via the death registry. Cox proportional hazard regression was used to evaluate associations between serum 25(OH)D in quintiles and all-cause mortality among individuals with IBD [Crohn disease (CD; n = 1760) and ulcerative colitis (UC; n = 3462)]. Restricted cubic splines were used to investigate potential nonlinearity.

RESULTS

During the mean follow-up period of 11.9 y, 529 deaths (198 in CD and 331 in UC) were documented among 5222 individuals with IBD. Compared with the lowest quintile of serum 25(OH)D, HRs for the second to the highest quintiles were 0.82 (95% CI: 0.63, 1.06), 0.63 (95% CI: 0.47, 0.83), 0.64 (95% CI: 0.48, 0.85), and 0.74 (95% CI: 0.55, 0.99), respectively. Nonlinearity was detected in the dose-response association between serum 25(OH)D concentration and all-cause mortality (P-nonlinearity < 0.001), and 25(OH)D concentrations of 44-78 nmol/L were associated with a 50% lower risk of all-cause mortality (than 10 nmol/L). Subgroup analyses showed that the nonlinear association mostly applied to females (P-nonlinearity < 0.001 compared with 0.080 in males).

CONCLUSIONS

We observed a nonlinear association, mostly applicable to females, between serum 25(OH)D concentrations and all-cause mortality among individuals with IBD. A 25(OH)D concentration range of 44-78 nmol/L can serve as a starting point for future research to confirm recommended 25(OH)D concentrations for individuals with IBD.

Vitamin D and colorectal cancer - A practical review of the literature

Colorectal cancer (CRC) is the third leading cause of cancer-related mortality in the United States and the second cause worldwide. Its incidence rates have been decreasing in the overall population in the US in the past few decades, but with increasing rates in the population younger than 50 years old. Environmental factors are supposed to be involved in the development of the disease, with strong evidence favoring an influence of the diet and lifestyle. A diet high in red meat and calories, and low in fiber, fruits and vegetables increases the risk of CRC, as well as physical inactivity. The influence of low calcium intake and low levels of vitamin D on the risk of the disease and on the clinical outcomes of CRC patients has also been investigated. Hypovitaminosis D has been highly prevalent worldwide and associated with several chronic diseases, including malignancies. Vitamin D is a steroid hormone with the main function of regulating bone metabolism, but with many other physiological functions, such as anti-inflammatory, immunomodulatory, and antiangiogenic effects, potentially acting as a carcinogenesis inhibitor. In this review, we aim to describe the relation of vitamin D with malignant diseases, mainly CRC, as well as to highlight the results of the studies which addressed the potential role of vitamin D in the development and progression of the disease. In addition, we will present the results of the pivotal randomized clinical trials that evaluated the impact of vitamin D supplementation on the clinical outcomes of patients with CRC.

The Role of Diet, Alcohol, BMI, and Physical Activity in Cancer Mortality: Summary Findings of the EPIC Study

Evidence on the impact of diet, alcohol, body-mass index (BMI), and physical activity on mortality due to cancer and other cancer-related outcomes is still scarce. Herein, we reviewed the contribution of the European Prospective Investigation into Cancer and Nutrition (EPIC) study to the current state of the art on the role of these factors in cancer mortality. We identified 45 studies using a rapid systematic review methodology. Dietary factors associated with reduced cancer mortality included raw vegetable intake; dietary fiber intake; the Mediterranean diet; other dietary scores; other diet patterns including low meat eaters, vegetarians/vegans, or fish eaters; dietary intake (or biomarkers) of some vitamins (e.g., vitamin D, vitamin K2, or Vitamin C); and intake of lignans. Physical activity and following healthy lifestyle recommendations also reduced cancer mortality risk. In contrast, dietary factors associated with higher cancer mortality risk included poor diet quality, consumption of alcohol and soft drinks including juice, and, to a lesser extent, intake of some fatty acids. Excess weight and obesity also increased the risk of cancer mortality. The EPIC study holds valuable information on diet and lifestyle factors and offers a unique opportunity to identify key diet-related factors for cancer mortality prevention.

Assessment the effect of vitamin D supplementation on plasma vitamin D levels, inflammation, and oxidative stress biomarkers based on vitamin D receptor genetic variation in breast cancer survivors: a protocol for clinical trial

BACKGROUND

Both human genes and environmental exposures, due to complex interplay, play important role in the cancer etiology. Vitamin D is associated with a reduced risk of incidence and mortality of several human cancers. This study will aim to investigate the possible effects of individual polymorphisms in vitamin D receptor (VDR) as well as effects of VDR haplotypes on response to vitamin D supplementation in breast cancer survivors.

METHODS

This is an interventional study in which the effects of vitamin D supplementation on plasma vitamin D levels, inflammatory and antioxidant biomarkers and factors associated with cell proliferation, differentiation, damage, and apoptosis will be investigated stratified by variations in VDR genotype. The present study will be conducted on breast cancer survivors referred to the Shohadaye Tajrish hospital and its associated clinics. One hundred ninety-eight breast cancer survivors will receive 4000 IU of vitamin D3 daily for 12 weeks. VDR Fok1, ApaI, TaqI, BsmI, and Cdx-2 genotype will be determined at the end of the study and responses to vitamin D supplements (inflammatory, antioxidant, cell proliferation, differentiation, damage, and apoptosis biomarkers) will be compared between the three subgroups of each VDR polymorphism as well as different VDR haplotype categories.

DISCUSSION

Genetic variation is a fundamental factor influencing individuals' divergent responses to diet, nutritional status, metabolic response, and diet-related health disorders. Furthermore, studies of gene and environment interactions will provide a precise and accurate assessments of individuals' dietary requirements by considering both the genetic and environmental aspects simultaneously. The results of the current study, to some extent, will highlight the discrepancies existing in the findings of different studies regarding vitamin D, VDR, and cancer by considering both the genetic and environmental aspects simultaneously. If responses to vitamin D supplementation could be modified by VDR SNPs, determining the distribution of VDR polymorphisms in both breast cancer survivors and healthy populations will provide a new insight into the vitamin D requirements of individuals to prevent cancer and its related mortality based on their genotypes. Trial registration This trial has been registered on Iranian Registry of Clinical Trials (IRCT) under the identification code: IRCT2017091736244N1, registration date: 2017-11-10, http://www.irct.ir/trial/27153.

The association between preoperative 25-OH vitamin D levels and postoperative complications in patients undergoing colorectal cancer surgery

BACKGROUND

Determining the modifiable risk factors for postoperative complications is particularly significant in patients undergoing colorectal surgery since those are associated with worse long-term outcomes.

METHODS

Consecutive newly diagnosed 104 colorectal cancer patients were prospectively included in this single-center observational study. Preoperative serum 25-OH vitamin D levels were measured and analyzed for infectious and postoperative complications.

RESULTS

Serum 25-OH vitamin D levels were found to be < 20 ng/ml in 74 patients (71.2%) and ≥ 20 ng/ml in 30 patients (28.8%); and the mean serum 25-OH vitamin D level was 15.95 (± 9.08) ng/ml. In patients with surgical site infection and infectious complications, 25-OH vitamin D levels were significantly lower than patients without complications (p = 0.036 and p = 0.026). However, no significant difference was demonstrated in 25-OH vitamin D levels according to overall postoperative complications.

CONCLUSIONS

Our results suggest that vitamin D levels might be a potential risk factor for infectious complications in patients undergoing colorectal cancer surgery.

Identification of Vitamin D-related gene signature to predict colorectal cancer prognosis

Colorectal cancer (CRC) is one of the most common malignant carcinomas worldwide with poor prognosis, imposing an increasingly heavy burden on patients. Previous experiments and epidemiological studies have shown that vitamin D and vitamin D-related genes play a vital role in CRC. Therefore, we aimed to construct a vitamin D-related gene signature to predict prognosis in CRC. The CRC data from The Cancer Genome Atlas (TCGA) was performed as the training set. A total of 173 vitamin D-related genes in the TCGA CRC dataset were screened, and 17 genes associated with CRC prognosis were identified from them. Then, a vitamin D-related gene signature consisting of those 17 genes was established by univariate and multivariate Cox analyses. Moreover, four external datasets (GSE17536, GSE103479, GSE39582, and GSE17537) were used as testing set to validate the stability of this signature. The high-risk group presented a significantly poorer overall survival than low-risk group in both of training set and testing sets. Besides, the areas under the curve (AUCs) for signature on OS in training set at 1, 3, and 5 years were 0.710, 0.708, 0.710 respectively. The AUCs of the ROC curve in GSE17536 for 1, 3, and 5 years were 0.649, 0.654, and 0.694. These results indicated the vitamin D-related gene signature model could effectively predict the survival status of CRC patients. This vitamin D-related gene signature was also correlated with TNM stage in CRC clinical parameters, and the higher risk score from this model was companied with higher clinical stage. Furthermore, the high accuracy of this prognostic signature was validated and confirmed by nomogram model. In conclusion, we have proposed a novel vitamin D-related gene model to predict the prognosis of CRC, which will help provide new therapeutic targets and act as potential prognostic biomarkers for CRC.

Role of Vitamin D in Colorectal Cancer: A Holistic Approach and Review of the Clinical Utility

Vitamin D is well known for its effects on the homeostasis of calcium and phosphorus. Lately, considerable research has brought the extra-skeletal role of vitamin D under the spotlight, including its anti-cancer activity. Colorectal cancer (CRC) is the most extensively studied neoplasia that has been observed to be affected by vitamin D; the list includes breast, prostate, and ovarian cancer. This review aims to shine a light on the influence of vitamin D over CRC and to further understand its ability to be used as a potential economical treatment for CRC patients. For this review, PubMed was used as the main database for the literature search. Studies on the role of vitamin D on CRC within 10 years and all of the study types were included. Post the extensive research over PubMed, it was noted that vitamin D, through its effect on multiple pathways, especially Wnt/β-catenin, apoptosis, and inflammation, hinders the progression of CRC carcinogenesis. High levels of this steroid hormone can delay the progression and may provide a cost-effective way of treating CRC patients. Further research and additional human trials are still due to bring about more knowledge on this topic. In conclusion, high serum levels of vitamin D are associated with a lower risk of incidence and progression of CRC.

Dietary Supplements Use among Adults with Cancer in the United States: A Population-Based Study

To assess the patterns of use of dietary supplements among cancer survivors in the United States in a population-based setting. National Health and Nutrition Examination Survey (NHANES) datasets (1999-2016) were accessed, and adult respondents (≥ 20 years old) with a known status of cancer diagnosis and a known status of dietary supplements intake were included. Multivariable logistic regression analysis was then used to assess factors associated with dietary supplements intake. Moreover, and to evaluate the impact of dietary supplements on overall survival among respondents with cancer, multivariable Cox regression analysis was conducted. A total of 49,387 respondents were included in the current analysis, including a total of 4,575 respondents with cancer. Among respondents with cancer, 3,024 (66.1%) respondents have reported the use of dietary supplements; while 1,551 (33.9%) did not report the use of dietary supplements. Using multivariable logistic regression analysis, factors associated with the use of dietary supplements included older age (OR: 1.028; 95% CI: 1.027-1.030); white race (OR for black race vs. white race: 0.67; 95% CI: 0.63-0.72); female gender (OR for males vs. females: 0.56; 95% CI: 0.53-0.59), higher income (OR: 1.13; 95% CI: 1.11-1.14), higher educational level (0.59; 95% CI: 0.56-0.63), better self-reported health (OR: 1.36; 95% CI: 1.17-1.58), health insurance (OR: 1.35; 95% CI: 1.27-1.44), and history of cancer (OR: 1.20; 95% CI: 1.10-1.31). Using multivariable Cox regression analysis and within the subgroup of respondents with a history of cancer, the use of dietary supplements was not found to be associated with a difference in overall survival (HR: 1.13; 95% CI: 0.98-1.30). Dietary supplement use has increased in the past two decades among individuals with cancer in the United States, and this increase seems to be driven mainly by an increase in the use of vitamins. The use of dietary supplements was not associated with any improvement in overall survival for respondents with cancer in the current study cohort.