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

Structural diversification of vitamin D using microbial biotransformations

Vitamin D deficiencies are linked to multiple human diseases. Optimizing its synthesis, physicochemical properties, and delivery systems while minimizing side effects is of clinical relevance and is of great medical and industrial interest. Biotechnological techniques may render new modified forms of vitamin D that may exhibit improved absorption, stability, or targeted physiological effects. Novel modified vitamin D derivatives hold promise for developing future therapeutic approaches and addressing specific health concerns related to vitamin D deficiency or impaired metabolism, such as avoiding hypercalcemic effects. Identifying and engineering key enzymes and biosynthetic pathways involved, as well as developing efficient cultures, are therefore of outmost importance and subject of intense research. Moreover, we elaborate on the critical role that microbial bioconversions might play in the a la carte design, synthesis, and production of novel, more efficient, and safer forms of vitamin D and its analogs. In summary, the novelty of this work resides in the detailed description of the physiological, medical, biochemical, and epidemiological aspects of vitamin D supplementation and the steps towards the enhanced and simplified industrial production of this family of bioactives relying on microbial enzymes. KEY POINTS: • Liver or kidney pathologies may hamper vitamin D biosynthesis • Actinomycetes are able to carry out 1α- or 25-hydroxylation on vitamin D precursors.

The Role of Dietary Vitamins and Antioxidants in Preventing Colorectal Cancer: A Systematic Review

The role of dietary vitamins and antioxidants in preventing colorectal cancer (CRC) is a significant area of research within nutritional oncology. However, the relationship between these nutrients and CRC prevention is complex and influenced by factors such as dosage, timing, and individual health status. This review aims to comprehensively analyze and synthesize the existing scientific literature on the potential role of dietary vitamins and antioxidants in preventing CRC. A comprehensive literature review was conducted by searching electronic databases to identify studies examining the prospected impacts of dietary vitamins and antioxidants on the prevention of CRC. According to the outcomes of this review, this research review shows a complex link between vitamins and CRC. While some vitamins such as B2, B6, and D seemed helpful, others such as A and E had mixed results. Vitamin C deficiency was even linked to worse outcomes in cancer patients. Overall, the studies suggest focusing on a balanced diet rich in various vitamins rather than relying solely on individual supplements to prevent CRC. On the other hand, the results of our review suggest that the relationship between antioxidant intake and CRC is more intricate than previously thought. Data from this review indicates that taking specific antioxidant supplements such as selenium and vitamin E does not seem to offer the same protection. This suggests that a balanced diet with a variety of antioxidants is more helpful than focusing on single supplements. While we did not observe a direct association, future studies could investigate how different types and combinations of antioxidants might influence CRC development. In conclusion, the present systematic review highlights the need for more research on the relationship between vitamins, antioxidants, and CRC. We need to understand how these nutrients affect both the survival of people with CRC and the prevention of the disease. This will help us determine the best ways to use vitamins and antioxidants in CRC management and prevention.

Plasma 25-hydroxyvitamin D deficiency in the peri-operative period is associated with survival outcome in colorectal cancer patients: a meta-analysis

AIM

Surgery had a significant impact on 25-hydroxyvitamin D (25-(OH)D) levels. Uncertainty still existed regarding the effects of peri-operative 25(OH)D deficiency on colorectal cancer (CRC) patients' prognosis. The purpose of the present study was to explore the potential association between the peri-operative 25(OH)D deficiency and the survival outcome of CRC.

METHODS

Seven electronic databases [including PubMed, EMBASE, Web of Science, The Cochrane Library, OvidMEDLINE(R), China National Knowledge Infrastructure (CNKI) and Wangfang data] were searched without language limitations. The primary outcomes were overall survival and all-cause mortality. Secondary outcomes were the incidence of 25(OH)D deficiency and risk variables for low 25(OH)D level in the peri-operative period.

RESULTS

14 eligible studies were obtained with 9324 patients for meta-analysis. In the peri-operative period, the pooled incidence of blood 25(OH)D deficiency was 59.61% (95% CI: 45.74-73.48). The incidence of blood 25(OH)D deficiency post-operatively (66.60%) was higher than that pre-operatively (52.65%, 95% CI: 32.94-72.36). Male (RR = 1.09, 95% CI: 1.03-1.16), rectum tumor (RR = 1.23, 95% CI: 1.03-1.47), spring and winter sampling (RR = 1.24, 95% CI: 1.02-1.49) were the risk factors for the 25(OH)D deficiency. The association between the low 25(OH)D post-operatively and short-term overall survival (HR = 0.43, 95% CI: 0.24-0.77) was most prominent, while a low 25(OH)D pre-operatively (HR = 0.47, 95% CI: 0.31-0.70) was more significantly associated with long-term all-cause mortality than that after surgery.

CONCLUSION

Peri-operative 25(OH)D impacted the CRC patients' prognosis. Due to possible confounding effects of systemic inflammatory response (SIR), simultaneous measurement of vitamin D and SIR is essential for colorectal survival.

Association Between CYP24A1 Polymorphisms and Bladder Cancer Risk in the Chinese Han Population

In this cohort of 217 bladder cancer patients and 484 healthy controls, we explored the association between CYP24A1 variants (rs2762934, rs1570669, rs6068816, rs2296241) and bladder cancer risk in the Chinese Han population. Utilizing the Agena MassARRAY system, we genotyped four selected CYP24A1 polymorphisms. Logistic regression revealed a significant association of rs2762934 and rs1570669 with elevated bladder cancer risk, while rs6068816 exhibited a protective effect. Bioinformatics analysis of CYP24A1 expression in normal and cancerous bladder tissues indicated higher expression in normal tissue. In conclusion, our findings highlight the potential role of CYP24A1 variants in bladder cancer susceptibility.

H19: An Oncogenic Long Non-coding RNA in Colorectal Cancer

Colorectal cancer (CRC) has been recorded amongst the most common cancers in the world, with high morbidity and mortality rates, and relatively low survival rates. With risk factors such as chronic illness, age, and lifestyle associated with the development of CRC, the incidence of CRC is increasing each year. Thus, the discovery of novel biomarkers to improve the diagnosis and prognosis of CRC has become beneficial. Long non-coding RNAs (lncRNAs) have been emerging as potential players in several tumor types, one among them is the lncRNA H19. The paternally imprinted oncofetal gene is expressed in the embryo, downregulated at birth, and reappears in tumors. H19 aids in CRC cell growth, proliferation, invasion, and metastasis via various mechanisms of action, significantly through the lncRNA-microRNA (miRNA)-messenger RNA (mRNA)-competitive endogenous RNA (ceRNA) network, where H19 behaves as a miRNA sponge. The RNA transcript of H19 obtained from the first exon of the H19 gene, miRNA-675 also promotes CRC carcinogenesis. Overexpression of H19 in malignant tissues compared to adjacent non-malignant tissues marks H19 as an independent prognostic marker in CRC. Besides its prognostic value, H19 serves as a promising target for therapy in CRC treatment.

Dissecting the role of the gut microbiome and fecal microbiota transplantation in radio- and immunotherapy treatment of colorectal cancer

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and poses a major burden on the human health worldwide. At the moment, treatment of CRC consists of surgery in combination with (neo)adjuvant chemotherapy and/or radiotherapy. More recently, immune checkpoint blockers (ICBs) have also been approved for CRC treatment. In addition, recent studies have shown that radiotherapy and ICBs act synergistically, with radiotherapy stimulating the immune system that is activated by ICBs. However, both treatments are also associated with severe toxicity and efficacy issues, which can lead to temporary or permanent discontinuation of these treatment programs. There's growing evidence pointing to the gut microbiome playing a role in these issues. Some microorganisms seem to contribute to radiotherapy-associated toxicity and hinder ICB efficacy, while others seem to reduce radiotherapy-associated toxicity or enhance ICB efficacy. Consequently, fecal microbiota transplantation (FMT) has been applied to reduce radio- and immunotherapy-related toxicity and enhance their efficacies. Here, we have reviewed the currently available preclinical and clinical data in CRC treatment, with a focus on how the gut microbiome influences radio- and immunotherapy toxicity and efficacy and if these treatments could benefit from FMT.

Beneficial effects of alpha-1 antitrypsin therapy in a mouse model of colitis-associated colon cancer

BACKGROUND

It is widely accepted that chronic inflammatory bowel diseases significantly higher a risk for colorectal cancer development. Among different types of treatments for patients with colon cancer, novel protein-based therapeutic strategies are considered.

AIM

To explore the effect of human plasma alpha-1 antitrypsin (AAT) protein in the chemically induced mouse model of colorectal cancer.

METHODS

BALB/c mice with azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colitis-associated colorectal cancer (CAC), we intraperitoneally treated with commercial preparation of human plasma AAT (4 mg per mouse). Effects of this therapy were evaluated histologically, and by immunohistochemical and gene expression assays.

RESULTS

When compared with non-treated controls, AOM/DSS mice receiving AAT therapy exhibited significantly longer colons, and less anal bleeding. Concurrently, AAT-treated mice had significantly fewer polyps, and lower numbers of large colon tumors. Immunohistochemical examinations of colon tissues showed significantly lower neutrophil counts, more granzyme B-positive but fewer MMP9 (gelatinase B)-positive cancer cells and lower numbers of apoptotic cells in mice receiving AAT therapy. The expression levels of IL4 were significantly higher while TNFA was slightly reduced in tumor tissues of AOM/DSS mice treated with AAT than in AOM/DSS mice.

CONCLUSION

Human AAT is an acute phase protein with a broad-protease inhibitory and immunomodulatory activities used as a therapeutic for emphysema patients with inherited AAT deficiency. Our results are consistent with previous findings and support an idea that AAT alone and/or in combination with available anti-cancer therapies may represent a new personalized approach for patients with colitis-induced colon cancer.

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.

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.

New Roles for Vitamin D Superagonists: From COVID to Cancer

Vitamin D is a potent steroid hormone that induces widespread changes in gene expression and controls key biological pathways. Here we review pathophysiology of vitamin D with particular reference to COVID-19 and pancreatic cancer. Utility as a therapeutic agent is limited by hypercalcemic effects and attempts to circumvent this problem have used vitamin D superagonists, with increased efficacy and reduced calcemic effect. A further caveat is that vitamin D mediates multiple diverse effects. Some of these (anti-fibrosis) are likely beneficial in patients with COVID-19 and pancreatic cancer, whereas others (reduced immunity), may be beneficial through attenuation of the cytokine storm in patients with advanced COVID-19, but detrimental in pancreatic cancer. Vitamin D superagonists represent an untapped resource for development of effective therapeutic agents. However, to be successful this approach will require agonists with high cell-tissue specificity.