Vitamins as Possible Cancer Biomarkers: Significance and Limitations

Abstract

The Western-style diet, which is common in developed countries and spreading into developing countries, is unbalanced in many respects. For instance, micronutrients (vitamins A, B complex, C, D, E, and K plus iron, zinc, selenium, and iodine) are generally depleted in Western food (causing what is known as ‘hidden hunger’), whereas some others (such as phosphorus) are added beyond the daily allowance. This imbalance in micronutrients can induce cellular damage that can increase the risk of cancer. Interestingly, there is a large body of evidence suggesting a strong correlation between vitamin intake as well as vitamin blood concentrations with the occurrence of certain types of cancer. The direction of association between the concentration of a given vitamin and cancer risk is tumor specific. The present review summarized the literature regarding vitamins and cancer risk to assess whether these could be used as diagnostic or prognostic markers, thus confirming their potential as biomarkers. Despite many studies that highlight the importance of monitoring vitamin blood or tissue concentrations in cancer patients and demonstrate the link between vitamin intake and cancer risk, there is still an urgent need for more data to assess the effectiveness of vitamins as biomarkers in the context of cancer. Therefore, this review aims to provide a solid basis to support further studies on this promising topic.

Vitamin C Deficiency in Blood Samples of COVID-19 Patients

“…In this study, we demonstrated that plasma ascorbate is lower in patients with COVID-19 than in uninfected SARS-CoV-2 negative individuals. The vitamins quantified are all considered essential for the immune response to viral infections [ 43 ], thus the study aimed at assessing whether they could play a role in SARS-CoV-2 infection. The data gathered herein did not show a COVID-19 specific decrease in blood calciferol or retinol as previously reported for COVID-19 [ 31 , 44 ], whereas the data confirmed previous investigations reporting decreased plasma ascorbate in COVID-19 cases [ 45 , 46 , 47 ] and the absence of relation between calcidiol and COVID-19 severity [ 48 ].…”

“…So far, two other studies reported low ascorbate levels in COVID-19 cases. Indeed, according to a recent study, vitamin C levels were undetectable in more than 90% of COVID-19 patients with ARDS [ 43 ]. Moreover, an epidemiological study reported that up to 82% of critically ill adult COVID-19 patients with ARDS had low vitamin C levels [ 45 , 49 ].…”

Minerals and Cancer: Overview of the Possible Diagnostic Value

“…Excess dietary phosphorus is linked to arteriosclerosis, renal dysfunction, premature aging, and cancer [ 119 ]. Intake of phosphorus is complicated by the fact that it is entangled with that of calcium and vitamin D, whose imbalance is also associated with an increased risk of cancer [ 120 ]. Moreover, even dietary fructose acts as an additional bias because it decreases the intestinal adsorption of phosphate [ 121 ].…”

“…Vitamin C, in the form of ascorbate (AscH – ) rescues leaked ferrous iron by converting ferric iron to Fe 2+ , which can be taken up by ferritin, but in the presence of a large amount of iron, it boosts the Fenton reaction by providing even more ferrous iron: Fe 3+ + AscH − → Fe 2+ + H + + Asc• − [ 150 ]. The ascorbic radical (Asc• − ) can also affect the mitochondrial respiration producing a ROS burst that causes even further cellular damage [ 120 ]. ROS is also part of several signal pathways (such as NF-κB, PI3K, and MAPK), hence, high levels of these free radicals promote aberration in cellular proliferation and inflammation [ 151 , 152 ].…”

Radial-EBUS: CryoBiopsy Versus Conventional Biopsy: Time-Sample and C-Arm

“…Lung cancer is usually diagnosed at a late stage due to a lack of early disease symptoms. We still do not have early blood biomarkers, such as in the case of prostate cancer, gastrointestinal cancer, and breast cancer [ 1 , 2 , 3 ]. Therefore, we have focused our efforts towards prevention with computed tomography scans of patients ≥50 years of age, smokers, former smokers, and patients with a known cancer family medical history [ 4 , 5 ].…”