Tumor-derived exosomes: Potential biomarkers and therapeutic target in the treatment of colorectal cancer.

Colorectal cancer (CRC) is the third most common cause of cancer-related death in men and women in many countries. Early detection of CRC helps to prevent the advanced stages of the disease, and may thereby improve the survival of these patients. A noninvasive test with high specificity and sensitivity is required for this. Exosomes are lipid bilayer membrane nanovesicles that are released into most body fluids and especially in the microenvironment of cancer. They carry various proteins, lipids, and nucleic materials such as DNA, RNA, messenger RNA (mRNA), and microRNA (miRNA), and may also alter the function of target cells. In this review, we aimed to describe the biogenesis, composition, function, and the role of tumor-derived exosomes in cancer progression. Moreover, their applications in tumor diagnosis and treatment are described, with a particular focus on CRC.

A genetic variant in the cytochrome P450 family 2 subfamily R member 1 determines response to vitamin D supplementation.

BACKGROUND: Globally, about 1 billion people have inadequate levels of serum vitamin D and it is prevalent in all ethnicities and age groups. Few foods naturally contain sufficient vitamin D; therefore, most people get their requirements through supplementation. Hence vitamin D status is affected by genetic and environmental determinants including season of measurement, diet habitual, health status, body mass index and concurrent medication. Further studies are necessary to understand how genetic variation influences vitamin D metabolism. We aimed to explore the association between a potential vitamin D-related polymorphism (the rs10766197 polymorphism in the CYP2R1 gene) with the response to supplementation of vitamin D in 253 healthy Iranian girls. MATERIAL AND METHOD: A total of 253 healthy subjects received 50,000 IU of vitamin D3 weekly for 9 weeks. Serum 25(OH)D concentrations and metabolic profiles were measured at baseline and after 9 weeks of supplementation. The genotypes of the CYP2R1 variant (rs10766197) were identified using TaqMan genotyping assays. RESULTS: Serum 25(OH)D during the supplementation, increased in all individuals. Subjects with a AA major genotype at this locus had higher vitamin D concentrations after intervention (Changes (%) 448.4% ± 425% in AA vs 382.7% ± 301% in GG). This genetic variant modulated the response to supplementation (p < 0.001 and p-value SNP = 0.05). Regression analysis showed that the probability of affecting serum 25(OH)D, in individuals who had homozygous major allele GG was two-fold higher than carriers of the uncommon allele A (OR = 2.1 (1-4.2); p = 0.03). Interestingly, the Hs-CRP was reduced in AA carries while was elevated in individuals with GG and AG genotypes, after high-dose vitamin D supplementation. CONCLUSION: Changes in serum vitamin D and metabolic profile following high dose supplementation with vitamin D were associated with CYP2R1 polymorphism. Although carriers of the common G allele showed a greater response in the serum vitamin D.

Interaction between a variant of CDKN2A/B-gene with lifestyle factors in determining dyslipidemia and estimated cardiovascular risk: A step toward personalized nutrition.

BACKGROUND & AIMS: Several genome-wide-association-studies have identified genetic variants in a region on chromosome 9p21 that are associated with an increased risk of Cardiovascular disease (CVD) and diabetes. Here we have explored the interaction of a genetic variant of the CDKN2A/B-rs10811661 gene locus with cardiovascular risk factors and environmental-exposures (e.g., diet and physical activity) in 1165 individuals recruited from the Mashhad-Stroke and Heart-Atherosclerotic-Disorders cohort. METHODS: Genotyping was carried out using TaqMan-real-time-PCR based method. The association of CDKN2A/B-rs10811661 locus and its interaction with dietary intake in association with the main determinants of dyslipidemia, and cardiovascular-risk-factors were assessed in 2 cohorts. RESULTS: Our data showed that obese subjects with a TT genotype had a higher level of TG, TG/HDL ratio and Hs-CRP, compared to the subjects with the wild type genotype, or individuals with a normal BMI. Moreover, the presence of a TT genotype was associated with increased risk of hypercholesterolemia, insulin resistance and CVD. These effects were more pronounced in the sub-group with low physical activity and a high dietary energy intake (e.g., the interaction between TT genotype and total energy intake on serum cholesterol was positive (RERI: 0.2, 95%CI (-0.96-1.3), AP: 0.1, 95%CI (-0.5-0.7) and SI: 1.2, 95%CI (0.3-5.1))). CONCLUSIONS: We have found a significant association between the CDKN2A-rs10811661 polymorphism with cardiovascular risk factors and dyslipidemia in a non-diabetic population. It is possible that a low energy diet and high physical activity could ameliorate the unfavorable effects of T allele of CDKN2A/B locus. Functional analysis is warranted to investigate the value of this genetic biomarker of CVD risk in obese people.

Metabolic syndrome components as markers to prognosticate the risk of developing chronic kidney disease: evidence-based study with 6492 individuals.

OBJECTIVE: The global prevalence of metabolic syndrome (MetS) appears to be increasing and the impact of this condition on potential comorbidities such as cardiovascular disease is high. Chronic kidney disease (CKD) is also a potential comorbidity of MetS but the method of screening for this is somewhat controversial. Thus, predictive markers that can predict the risk of developing CKD are warranted for identification of patients with MetS at an increased risk. RESEARCH METHODS/PATIENTS: We investigated the occurrence of CKD in 6492 individuals, either with or without MetS. RESULTS: Our results showed that the prevalence of CKD was markedly higher in those individuals with MetS, and increased progressively with the number of MetS components and age. Waist circumference, triglycerides and high-density lipoprotein cholesterol were significantly (p<0.05) associated with altered levels of urea nitrogen, glomerular filtration rate and creatinine, and were related to the increased risk of CKD (eg, OR 1.293 (95% CI 1.10 to 1.52; p=0.002)). The relative risk of CKD remained statistically significant for uric acid following multivariate analyses and adjusting for MetS-associated factors. CONCLUSIONS: Our data demonstrated the association of MetS components with CKD in our population and revealed that susceptibility to CKD was increased with the number of defining features of MetS. These findings prompt prospective studies to determine the impact of preventing and detecting MetS on the risk of developing CKD.