Serum levels of trace elements in patients with prostate cancer

Serum Trace Element Levels in Cancer Patients Undergoing Chemotherapy: a Before-After Analysis

Trace elements (TEs) play a crucial role in metabolism through their biochemical and catalytic effects, and alterations in their levels have been observed in various malignancies. Given that chemotherapy is a common treatment for cancer, it is important to understand how it may affect the levels of TEs in the body. By investigating changes in TEs levels before and after chemotherapy, this study aims to provide insights into the potential impact of chemotherapy on TEs levels in cancer patients. In the present study, analyses were performed on the serum level of some elements including Zn, Cu, Cd, and Se in 69 patients with leukemia, lymphoma, prostate and breast cancers before and after three courses of chemotherapy. The serum TEs were measured by atomic absorption spectroscopy. The serum Zn levels in patients with leukemia, lymphoma, and breast cancer significantly decreased after chemotherapy (P < 0.05). Significant reductions were also observed in the post-chemotherapy serum level of Cd in patients with prostate (P = 0.020) and breast cancer (P = 0.013). Moreover, the Se serum level significantly decreased after chemotherapy compared to before it in the breast cancer patients (P < 0.001). In contrast, the serum level of Cu was higher before than after chemotherapy in all the patients, but no significant difference was found (P > 0.05). The results show that chemotherapy can alter the level of TEs. The assessment of TEs in cancer patients may provide information about the side effects of chemotherapy as well as the use of appropriate strategies to better manage the clinical conditions of patients.

Concentration of serum trace elements in leukemia and lymphoma: A case-control study

Objective

Trace elements (TEs) have electrochemical and catalytic effects and play a crucial role in metabolism. A change in the concentrations of specific TEs may be associated with the incidence of various diseases such as solid tumors and hematological malignancies. By comparing the concentrations of TEs in the cases and controls, this study aims to provide insights into the possible impacts of TEs concentration on the incidence of leukemia and lymphoma.

Materials and methods

In the current study, the serum concentrations of Zn, Cu, Cd, Fe, and Se were analyzed for 20 patients with leukemia and lymphoma and 20 healthy individuals. Those concentrations were measured by atomic absorption spectroscopy.

Results

The serum Zn concentration in the cases was significantly lower than that in the controls (P < 0.05). The serum concentrations of Cu, Cd and Fe were also lower in the cases than in the controls. However, no significant difference was found (P > 0.05). Also, the serum concentration of Se was higher in the patients than in the controls, but no significant difference was found (P > 0.05).

Conclusion

The results indicate that a low serum concentration of Zn may be associated with the incidence of leukemia and lymphoma. The assessment of TEs in hematological malignancies may be of a prognostic value and provide knowledge about the side effects of alterations in the concentration of those elements. It may also lead to the use of suitable strategies to better manage the clinical conditions of patients.

Intake of oligoelements with cytarabine or etoposide alters dopamine levels and oxidative damage in rat brain

Research on the relationships between oligoelements (OE) and the development of cancer or its prevention is a field that is gaining increasing relevance. The aim was to evaluate OE and their interactions with oncology treatments (cytarabine or etoposide) to determine the effects of this combination on biogenic amines and oxidative stress biomarkers in the brain regions of young Wistar rats. Dopamine (DA), 5-Hydroxyindoleacetic acid (5-Hiaa), Glutathione (Gsh), Tiobarbituric acid reactive substances (TBARS) and Ca+2, Mg+2 ATPase enzyme activity were measured in brain regions tissues using spectrophometric and fluorometric methods previously validated. The combination of oligoelements and cytarabine increased dopamine in the striatum but decreased it in cerebellum/medulla-oblongata, whereas the combination of oligoelements and etoposide reduced lipid peroxidation. These results suggest that supplementation with oligoelements modifies the effects of cytarabine and etoposide by redox pathways, and may become promising therapeutic targets in patients with cancer.

Concentration of trace elements in blood of Polish patients with prostate cancer

The goal of the study was to analyse the concentrations of chemical elements (Fe, Ni, As, Cd, Pb, Hg, Cr, Zn) which are important for the determination of environmental toxins (e.g. resulting from smoking, exposure to harmful agents at work) in Polish patients with prostate cancer. The study covered 66 patients with diagnosed prostate cancer and 64 healthy volunteers over 50 years old. The analysis of the concentrations of selected chemical elements in whole blood was performed using inductively coupled plasma mass spectrometry (ICP-MS). In their blood, the patients with cancer had a significantly higher concentration of only one of the examined elements: arsenic. Additionally, the study group had lower concentrations of chromium, zinc, but also cadmium and lead, which are commonly regarded as carcinogenic. Taking into consideration the control group of healthy subjects of this study, we can assume that the subjects with prostate cancer were exposed to higher levels of arsenic, and that exposure to this element may be associated with an increased risk of cancer.

Blood Pb levels are associated with prostate cancer prevalence among general adult males: Linking National Cancer Registry (2002-2017) and KNHANES (2008-2017) databases of Korea

BACKGROUND

Exposure to heavy metals may increase the risk of developing prostate cancer. However, these observations are often inconsistent and not based on clinically diagnosed cases.

OBJECTIVE

To investigate the association of lead (Pb), cadmium (Cd), and mercury (Hg) exposure with clinically determined prostate cancer cases among adult males in South Korea.

METHODS

Metal biomonitoring data and cancer information from the general Korean population were extracted by linking National Cancer Center (NCC) cancer registration data (2002-2017) with Korea National Health and Nutrition Examination Survey (KNHANES) data (2008-2017). Among them, 46 prostate cancer cases (designated as 'all-prostate'), including 25 diagnosed after heavy metal measurement (designated as 'post-prostate'), and 93 matching controls were chosen. Logistic regression analysis was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) between the heavy metal levels and prostate cancer.

RESULTS

Post-prostate patients exhibited higher blood Pb levels than controls (median 3.1 μg/dL vs. 2.38 μg/dL, p = 0.01). For all-prostate cancer, the OR of prostate cancer increased by 2.04-fold for every doubling of Pb levels (95% CI = 1.08-3.87, p = 0.03). The OR was also significantly elevated when comparing the third quartile (Q3) to the lowest quartile (Q1), with ORs ranging from 3.38 to 7.95, depending on model (p < 0.05). Blood Pb levels maintained a positive association with inconsistent significance for post-prostate cancer patients. For Cd and Hg, no statistically significant association was established.

SIGNIFICANCE

By linking two national health databases for the first time, we constructed an unbiased database of prostate cancer cases and matching controls. We found that blood Pb concentrations were associated with the risk of prostate cancer in Korean men at the current level of exposure.

Micronutrients Importance in Cancer Prevention-Minerals

Cancer, a non-communicable disease with diverse kinds is one of the major global problems with high incidence and no proven method to prevent or treat. Minerals including trace elements are significant micronutrients for preserving the body's typical physiological function. In contrast to extremely processed industrial food, they are rich in natural sources of food and frequently included in nutritional supplements. The daily intake, storage capacities, and homeostasis of micronutrients depend on specific dietary practices in contemporary civilization and can be disturbed by various malignancies. Varied minerals have different effects on the status of cancer depending on how they affect these pathways. The outcomes could differ depending on the mineral such as calcium's supply and the cancer's location. A mineral called zinc helps the immune system function better and aids in wound healing. On the other hand, selenium exhibits anti-oxidant functions and has a dose-response relationship with many cancer types. However, this component can make the patient's condition worse. Although the body produces free radicals when iron is deficient, anaemia affects a patient's quality of life and ability to receive therapy. This chapter compiles the knowledge of minerals connected to unusual accumulation or depletion states in various malignancies.

Zinc: From Biological Functions to Therapeutic Potential

The trace element zinc (Zn) displays a wide range of biological functions. Zn ions control intercellular communication and intracellular events that maintain normal physiological processes. These effects are achieved through the modulation of several Zn-dependent proteins, including transcription factors and enzymes of key cell signaling pathways, namely those involved in proliferation, apoptosis, and antioxidant defenses. Efficient homeostatic systems carefully regulate intracellular Zn concentrations. However, perturbed Zn homeostasis has been implicated in the pathogenesis of several chronic human diseases, such as cancer, diabetes, depression, Wilson's disease, Alzheimer's disease, and other age-related diseases. This review focuses on Zn's roles in cell proliferation, survival/death, and DNA repair mechanisms, outlines some biological Zn targets, and addresses the therapeutic potential of Zn supplementation in some human diseases.

Plasma Micronutrient Profile of Prostate Cancer Cases Is Altered Relative to Healthy Controls-Results of a Pilot Study in South Australia

Emerging evidence suggests possible roles of micronutrients in cancer prevention. The study was designed to test the hypothesis that the concentration profile of plasma micronutrients (i.e., the nutriome) in prostate cancer patients is different from that of healthy controls. Plasma samples from 116 Caucasian men diagnosed with late onset of prostate cancer and 132 matched controls from the South Australian population were collected and analysed for their concentration of micronutrients. Plasma concentrations of lutein, lycopene, α-carotene and β-carotene were found to be significantly lower in prostate cancer patients (p = 0.03, 0.008, 0.002 and 0.002, respectively). Plasma levels of elements such as iron, copper, calcium and sulphur were significantly higher (p < 0.0001, <0.0001, <0.0001 and p = 0.0003, respectively) while that of selenium was significantly lower (p = 0.002) in prostate cancer patients. Higher prostate cancer risk is significantly associated with plasma levels below the median of lycopene (OR: 2.24), α-carotene (OR: 2.13), β-carotene (OR: 1.97) and high levels above the median of iron (OR: 2.31), calcium (OR: 4.35) and sulphur (OR: 2.39). The results of this study suggest that the plasma nutriome could be a useful diagnostic of prostate cancer risk.

Genetically predicted iron status was associated with the risk of prostate cancer

Introduction

Observational studies have reported a relationship between iron status and the risk of prostate cancer. However, it remains uncertain whether the association is causal or due to confounding or reverse causality. To further clarify the underlying causal relationship, we conducted a Mendelian randomization (MR) analysis.

Methods

We selected three genetic variants (rs1800562, rs1799945, and rs855791) closely correlated with four iron status biomarkers (serum iron, log-transformed ferritin, transferrin saturation, and transferrin) as instrumental variables. Summary statistics for prostate cancer were obtained from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome consortium including 79,148 cases and 61,106 controls of European ancestry. The inverse-variance weighted (IVW) method was conducted primarily to estimate the association of genetically predicted iron status and the risk of prostate cancer, supplemented with simple-median, weighted-median and maximum-likelihood methods as sensitivity analysis. MR-Egger regression was used to detect directional pleiotropy. We also conducted a meta-analysis of observational studies to assess the associations between iron status and the risk of prostate cancer.

Results

Genetically predicted increased iron status was associated with the decreased risk of prostate cancer, with odds ratio of 0.91 [95% confidence interval (CI): 0.84, 0.99; P = 0.035] for serum iron, 0.81 (95% CI: 0.65, 1.00; P = 0.046) for log- transformed ferritin, 0.94 (95% CI: 0.88, 0.99; P = 0.029) for transferrin saturation, and 1.15 (95% CI: 0.98, 1.35; P = 0.084) for transferrin (with higher transferrin levels representing lower systemic iron status), using the inverse-variance weighted method. Sensitivity analyses produced consistent associations, and MR-Egger regression indicated no potential pleiotropy. Our replication analysis based on FinnGen research project showed compatible results with our main analysis. Results from our meta-analysis similarly showed that serum ferritin [standardized mean difference (SMD): -1.25; 95% CI: -2.34, -0.16; P = 0.024] and transferrin saturation (SMD: -1.19; 95% CI: -2.34, -0.05; P = 0.042) were lower in patients with prostate cancer compared with that in controls.

Discussion

Our study suggests a protective role of iron in the risk of prostate cancer, further investigations are required to clarify the underlying mechanisms.

Environmental Exposure to Metals, Parameters of Oxidative Stress in Blood and Prostate Cancer: Results from Two Cohorts

We studied the potential role of exposure to various metal(oid)s (As, Cd, Cr, Hg, Ni, and Pb) in prostate cancer. Two cohorts were established: the Croatian cohort, consisting of 62 cases and 30 controls, and the Serbian cohort, consisting of 41 cases and 61 controls. Blood/serum samples were collected. Levels of investigated metal(oid)s, various parameters of oxidative stress, and prostate-specific antigen (PSA) were determined in collected samples. A comparison of the measured parameters between 103 prostate cancer patients and 91 control men from both Croatian and Serbian cohorts showed significantly higher blood Hg, SOD, and GPx levels and significantly lower serum SH levels in prostate cancer patients than in controls. Correlation analyses revealed the significant relationship between certain parameters of oxidative stress and the concentrations of the measured metal(loid)s, pointing to the possible role of metal(oid)-induced oxidative stress imbalance. Furthermore, a significant inverse relationship was found between the blood Pb and the serum PSA in prostate cancer patients, but when the model was adjusted for the impacts of remaining parameters, no significant association between the serum PSA and the measured parameters was found. The results of the overall study indicate a substantial contribution of the measured metal(loid)s to the imbalance of the oxidant/antioxidant system. Although somewhat conflicting, the results of the present study point to the possible role of investigated metal(oid)s in prostate cancer, especially for Hg, since the obtained relationship was observed for both cohorts, followed by the disturbances in oxidative stress status, which were found to be correlated with Hg levels. Nevertheless, further studies in larger cohorts are warranted to explain and confirm the obtained results.

Serum trace element levels of gastrointestinal cancer patients in an endemic upper gastrointestinal cancer region

Gastrointestinal (GI) cancers are an important cause of the death rate in Turkey and in the world. Especially upper (esophageal and gastric) GI cancers are the leading types of cancer by 20-27% in Eastern Turkey. Trace elements are involved in many physiological and metabolic processes in the human body. Recent studies suggest that the increase or decrease of trace elements in the body may be related to the formation and development of many diseases such as cancers, diabetes mellitus and cardiovascular diseases etc. METHOD AND MATERIALS: In this study some trace elements; cadmium (Cd), cobalt (Co), Copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), nickel (Ni), lead (Pb), zinc (Zn) concentrations were investigated in the blood serums of esophageal, gastric and colon cancer patients and healthy controls in Van city area, an endemic upper (esophageal and gastric) GI region of Eastern Turkey. The analysis of the elements was realized with a flame atomic absorption spectrophotometer (FAAS). RESULTS: Mean serum levels of Cd and Ni in esophageal and gastric cancer patients were very significantly lower compared to controls (p < 0.001 and < 0.005). In addition, the mean serum Co level of esophageal cancer patients was very significantly lower than in controls and gastric cancer patients (p < 0.002). Also, the mean serum levels of Fe and Mn in all (esophageal, gastric and colon) cancer groups were very significantly lower than in controls (p < 0.001 and 0.002). Mean serum levels of Cu, Mg, Pb and Zn were not significantly different in all cancer patients compared to controls. CONCLUSION: We have detected the deficiency of five trace elements (Fe, Mn, Cd, Ni, Co) in esophageal, gastric and colon cancer patients. The deficiencies of trace elements may be due to malign over consumption of the nutrients and to the malnutrition of the advanced cancer patients. Nutritional therapy rich in trace elements should be considered as one of the strategies to fight against cancers.

Identification of two-dimensional copper signatures in human blood for bladder cancer with machine learning

Currently, almost all available cancer biomarkers are based on concentrations of compounds, often suffering from low sensitivity, poor specificity, and false positive or negative results. The stable isotopic composition of elements provides a different dimension from the concentration and has been widely used as a tracer in geochemistry. In health research, stable isotopic analysis has also shown potential as a new diagnostic/prognostic tool, which is still in the nascent stage. Here we discovered that bladder cancer (BCa) could induce a significant variation in the ratio of natural copper isotopes (⁶⁵Cu/⁶³Cu) in the blood of patients relative to benign and healthy controls. Such inherent copper isotopic signatures permitted new insights into molecular mechanisms of copper imbalance underlying the carcinogenic process. More importantly, to enhance the diagnostic capability, a machine learning model was developed to classify BCa and non-BCa subjects based on two-dimensional copper signatures (copper isotopic composition and concentration in plasma and red blood cells) with a high sensitivity, high true negative rate, and low false positive rate. Our results demonstrated the promise of blood copper signatures combined with machine learning as a versatile tool for cancer research and potential clinical application.

The blood Cu concentration and isotopic composition enable new insights into Cu imbalance and diagnosis of bladder cancer with machine learning.

Age-Related Changes in Zinc, Copper and Selenium Levels in the Human Prostate

Pathophysiological changes in the prostate gland-benign prostatic hyperplasia (BPH) and prostatic adenocarcinoma (PCa)-are closely related to the age of men. In the prostate gland, zinc is of particular importance for its proper functioning, especially with regard to the effects of hormonal disorders. The aim of this study was to evaluate zinc, copper and selenium concentrations in different parts of the prostate gland in relation to age and the nature of pathological changes. Zinc and copper were determined by the AAS method and selenium by the spectrofluorometric method. The concentration of zinc in the central part of the prostate increases with age, and in patients over 36 years it is twice as high as in the peripheral part, where no increase in the level of this element was observed with the age of patients. The above data confirm a possible influence of zinc on the formation of PCa (located mostly in the peripheral part of the prostate, with low levels of zinc) and BPH in the central part where the levels of this element are the highest. The results apparently confirm the disturbed homeostasis of zinc and other essential elements in the etiology of BPH and PCa.

Analysis of trace elements in human hair through X-ray fluorescence spectroscopy for screening of prostate cancer

Background: Use of hair samples to analyze the trace element concentrations is one of the interesting fields among many researchers. X-ray fluorescence (XRF) is considered as one of the most common methods in studying the concentration of elements in tissues and also crystalline materials, using low energy X-ray. In the present study, we aimed to evaluate the concentration of the trace elements in the scalp hair sample through XRF spectroscopy using signal processing techniques as a screening tool for prostate cancer. Methods: Hair samples of 22 men (including 11 healthy and 11 patients) were analyzed. All the sample donors were Iranian men. EDXRF method was used for the measurements. Signals were analyzed, and signal features such as mean, root-mean-square (RMS), variance, and standard deviation, skewness, and energy were investigated. The Man-Whitney U test was used to compare the trace element concentrations. The analysis of variance (ANOVA) test was used to identify which extracted feature could help to identify healthy and patient people. P values ≤ 0.05 were considered statistically significant. Statistical analysis was performed using SPSS 16.0 software. Results: The mean±SD age was 67.8±8.7 years in the patient group and 61.4±6.9 years in the healthy group. There were statistically significant differences in the aluminum (Al, P<0.001), silicon (Si, P=0.006), and phosphorus (P, P=0.028) levels between healthy and patient groups. Skewness and variance were found to be relevant in identifying people with cancer, as signal features. Conclusion: The use of EDXRF is a feasible method to study the concentration of elements in the hair sample, and this technique may be effective in prostate cancer screening. Further study with a large sample size will be required to elucidate the efficacy of the present method in prostate cancer screening.

Copper metabolism as a unique vulnerability in cancer

The last 25 years have witnessed tremendous progress in identifying and characterizing proteins that regulate the uptake, intracellular trafficking and export of copper. Although dietary copper is required in trace amounts, sufficient quantities of this metal are needed to sustain growth and development in humans and other mammals. However, copper is also a rate-limiting nutrient for the growth and proliferation of cancer cells. Oral copper chelators taken with food have been shown to confer anti-neoplastic and anti-metastatic benefits in animals and humans. Recent studies have begun to identify specific roles for copper in pathways of oncogenic signaling and resistance to anti-neoplastic drugs. Here, we review the general mechanisms of cellular copper homeostasis and discuss roles of copper in cancer progression, highlighting metabolic vulnerabilities that may be targetable in the development of anticancer therapies.

Serum and Saliva Concentrations of Biochemical Parameters in Men with Prostate Cancer and Benign Prostate Hyperplasia

OBJECTIVES

To find suitable biomarkers for diagnosis of prostate cancer (PC) in serum and saliva; also, to evaluate the diagnostic efficacy of saliva in patients with PC.

METHODS

This case-control study included 20 patients with PC and 20 patients with benign prostatic hyperplasia (BPH). Blood and saliva were collected from the participants and centrifuged. Serum and supernatant saliva were used for biochemical analysis. We evaluated serum and salivary levels of urea, creatinine, prostate-specific antigen (PSA), creatine kinase BB (CK-BB), zinc, β-2 microglobulin (B2M), and melatonin. Also, we used Mann-Whitney U testing, Spearman correlation coefficients, and receiver operating characteristic (ROC) analysis to evaluate the data.

RESULTS

Serum and salivary concentrations of urea, creatinine, PSA, CK-BB, zinc, and B2M were significantly higher in patients with PC, compared with the BPH group (P <.05). However, serum and salivary concentrations of melatonin were significantly lower in patients with PC, compared with BPH group (P <.05). In both groups, salivary concentrations of all markers were lower (P <.05), compared with those values in serum. We observed positive correlation between serum and salivary concentrations of all markers studied (P <.05).

CONCLUSION

From the data, we conclude that investigation using saliva specimens is a noninvasive, simple, and effective tool for screening of biochemical parameters.

Serum Copper and Zinc Levels in Patients with Endometrial Cancer

The aim of the present study was to evaluate serum concentrations of copper (Cu) and zinc (Zn), in relation with metabolic profile and clinicopathologic features of patients with endometrial cancer. A total of 47 women with endometrial cancer and 45 controls were eligible for the study. Clinicopathologic features and metabolic profile as well as serum copper and zinc levels were evaluated in each subject. Patients with endometrial cancer (Cu mean 3.72 ± 2.15 mg/L, median 3.54 [0.41-9.16] mg/L and Zn mean 1.83 ± 0.71 mg/L, median 1.77 [0.71-4.02] mg/L) exhibited lower Cu and Zn levels than those of controls (Cu mean 6.06 ± 1.79 mg/L, median 6.32 [2.95-9.05] mg/L and Zn mean 2.48 ± 0.89 mg/L, median 2.23 [1.23-4.54] mg/L) (p < 0.001). Cu/Zn ratio was also higher (0.85 ± 1.96 vs. 2.57 ± 0.73) in controls as compared with patients with endometrial cancer. While Cu levels showed no significant correlation with age, body mass index, gravidity, and parity, a positive correlation was found between Zn levels and parity. When cancer patients were evaluated on their own, both Cu and Zn levels showed positive correlation with age. Additionally, the cancer patients with myometrial invasion > 1/2 exhibited lower Cu levels compared with the cancer patients with myometrial invasion < 1/2. The data of the present study suggested that women with endometrial cancer are characterized by altered serum Cu and Zn levels as compared with controls. Imbalance of these trace element levels might be associated with endometrial cancer among Turkish patients.

Advances of Zinc Signaling Studies in Prostate Cancer

Prostate cancer (PCa) is one of the most common cancers and the second leading cause of cancer-related death among men worldwide. Despite progresses in early diagnosis and therapeutic strategies, prognosis for patients with advanced PCa remains poor. Noteworthily, a unique feature of healthy prostate is its highest level of zinc content among all soft tissues in the human body, which dramatically decreases during prostate tumorigenesis. To date, several reviews have suggested antitumor activities of zinc and its potential as a therapeutic strategy of PCa. However, an overview about the role of zinc and its signaling in PCa is needed. Here, we review literature related to the content, biological function, compounds and clinical application of zinc in PCa. We first summarize zinc content in prostate tissue and sera of PCa patients with their clinical relevance. We then elaborate biological functions of zinc signaling in PCa on three main aspects, including cell proliferation, death and tumor metastasis. Finally, we discuss clinical applications of zinc-containing compounds and proteins involved in PCa signaling pathways. Based on currently available studies, we conclude that zinc plays a tumor suppressive role and can serve as a biomarker in PCa diagnosis and therapies.

Association between serum heavy metals and prostate cancer risk - A multiple metal analysis

BACKGROUND

Prostate cancer is one of the most prevalent cancers in men. Exposure to heavy metals and their association with prostate cancer risk has been studied extensively, but combined effects remain largely inconclusive.

OBJECTIVES

To elucidate the association between serum concentrations of heavy metals and prostate cancer risk.

METHODS

Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the concentrations of a panel of 10 heavy metals (Mn, Cu, Zn, As, Se, Sb, Co, Cu, Cd and Pb) in serum samples of 141 cases and 114 controls in the Singapore Prostate Cancer Study. Linear probit regression models were used to estimate risk differences (RDs) and 95% confidence intervals (CIs) for the associations between log-centered serum metal concentrations and prostate cancer risk with adjustment for potential confounders. Bayesian kernel machine regression (BKMR) models were used to account for nonlinear, interactive, and joint metal effects.

RESULTS

Using probit regression, four heavy metals (As, Zn, Mn, Sb) were significantly and positively associated with prostate cancer risk in the unadjusted models. Using BKMR analysis, both As and Zn had positive risk differences on prostate cancer risk when all other metals were held fixed at the 25th and 50th percentiles (RD, 25th percentile: As: 0.15, Zn: 0.19, RD, 50th percentile: As: 0.45, Zn: 0.37). In addition, the overall mixture risk difference was positive and the 95% credible intervals did not include 0 when all metals in the mixture were jointly above their 55th percentile, as compared to when all metals were below their median values.

CONCLUSIONS

In summary, we found positive associations between the serum levels of As and Zn and prostate cancer risk on the risk difference scale using BKMR models. The overall mixture effect was also associated with increased prostate cancer risk. Future studies are warranted to validate these findings in prospective studies.

The crosstalk between trace elements with DNA damage response, repair, and oxidative stress in cancer

DNA damage response (DDR) is a regulatory system responsible for maintaining genome integrity and stability, which can sense and transduce DNA damage signals. The severity of damage appears to determine DDRs, which can include damage repair, cell-cycle arrest, and apoptosis. Furthermore, defective components in DNA damage and repair machinery are an underlying cause for the development and progression of various types of cancers. Increasing evidence indicates that there is an association between trace elements and DDR/repair mechanisms. In fact, trace elements seem to affect mediators of DDR. Besides, it has been revealed that oxidative stress (OS) and trace elements are associated with cancer development. In this review, we discuss the role of some critical trace elements in the risk of cancer. In addition, we provide a brief introduction on DDR and OS in cancer. Finally, we will further review the interactions between some important trace elements including selenium, zinc, chromium, cadmium, and arsenic, and DDR, and OS in cancer.

Copper and zinc in stage I multiple myeloma: relation with ceruloplasmin, lipid peroxidation, and superoxide dismutase activity

Background The main aim of this study was to assess the serum levels of copper (Cu), zinc (Zn) with lipid peroxidation, Cu/Zn superoxide dismutase (Cu/Zn SOD) activity, and ceruloplasmin (Cp) in multiple myeloma (MM) patients. Materials and methods The study was conducted in 34 MM patients at stage I. Serum Cu and Zn levels were measured by atomic absorption spectrometry. Also, spectrophotometric assays of malondialdehyde (MDA) levels in addition to Cp and Cu/Zn SOD were quantitated. Results The results showed a significant decrease in the serum Zn levels in patients with MM (p < 0.0001). Also, serum Cu levels were significantly higher (p < 0.0001). However, the serum Cu/Zn ratio was significantly higher in the cancer patients (p < 0.0001). A significant difference was observed in the patients group compared with the control group according to the Cu/Zn SOD activity (p < 0.0001). Moreover, serum levels of Cp and MDA were significantly increased in patients (p < 0.0001, both). Conclusions The elevated levels of serum Cu and MDA with a decrease in Zn and Cu/Zn SOD might explain the increased oxidative stress in MM disease. As the high Cu level was observed in MM patients, therefore, Cu levels should be concentrated in the pathogenesis and progression of MM disease.

Association of zinc level and polymorphism in MMP-7 gene with prostate cancer in Polish population

INTRODUCTION

Prostate cancer is one of the most commonly diagnosed malignancies among men in Western populations. Evidence reported in the literature suggests that zinc may be related to prostate cancer. In this study we evaluated the association of serum zinc levels and polymorphisms in genes encoding zinc-dependent proteins with prostate cancer in Poland.

METHODS

The study group consisted of 197 men affected with prostate cancer and 197 healthy men. Serum zinc levels were measured and 5 single nucleotide polymorphisms in MMP-1, MMP-2, MMP-7, MMP-13, MT2A genes were genotyped.

RESULTS

The mean serum zinc level was higher in prostate cancer patients than in healthy controls (898.9±12.01 μg/l vs. 856.6±13.05 μg/l, p<0.01). When compared in quartiles a significant association of higher zinc concentration with the incidence of prostate cancer was observed. The highest OR (OR = 4.41, 95%CI 2.07-9.37, p<0.01) was observed in 3rd quartile (>853.0-973.9 μg/l). Among five analyzed genetic variants, rs11568818 in MMP-7 appeared to be correlated with 2-fold increased prostate cancer risk (OR = 2.39, 95% CI = 1.19-4.82, p = 0.015).

CONCLUSION

Our results suggest a significant correlation of higher serum zinc levels with the diagnosis of prostate cancer. The polymorphism rs11568818 in MMP-7 gene was also associated with an increased prostate cancer risk in Poland.

Serum Copper and Zinc Levels Among Iranian Colorectal Cancer Patients

Alterations of trace element concentrations adversely affect biological processes and could promote carcinogenesis. Only a few studies have investigated the degree of changes in copper and zinc levels in colorectal cancer (CRC). The aim of the present study was to compare the serum copper (Cu) and zinc (Zn) concentrations in patients with CRC from Iran with those of healthy subjects. Cu and Zn concentrations in the serum of 119 cancer patients and 128 healthy individuals were measured by atomic absorption spectrometry. We found a significant decrease in the total mean serum Cu and Zn concentrations in CRC patients as compared with the control group (137.5 ± 122.38 vs. 160.68 ± 45.12 μg/dl and 81.04 ± 52.05 vs. 141.64 ± 51.75, respectively). However, the serum Cu/Zn ratio in the patient group was significantly higher than that measured in the control group (p = 0.00). There was no significant difference in the mean values of serum Cu and Zn concentrations between young (<60 years) and elderly (≥60 years) patients. However, the Cu/Zn ratio in <60-year cases was significantly higher than that in ≥60-year age group (p < 0.05). In addition, mean serum Cu level in normal weight patients was significantly higher than that in overweight/obese cases (132.31 ± 87.43 vs. 103.81 ± 53.72 μg/dl, respectively) (p < 0.05). There was no difference in mean serum Cu and Zn concentrations in patients stratified by the site, stage, or differentiation grade of tumors. Our findings suggest that imbalance in Cu and Zn trace element level is associated with CRC and might play an important role in cancer development among Iranian patients.

Status and Interrelationship of Zinc, Copper, Iron, Calcium and Selenium in Prostate Cancer

Deficiency or excess of certain trace elements has been considered as risk factor for prostate cancer. This study was aimed to detect differential changes and mutual correlations of selected trace elements in prostate cancer tissue versus benign prostatic hyperplasia tissue. Zinc, copper, iron, calcium and selenium were analysed in histologically proven 15 prostate cancer tissues and 15 benign prostatic hyperplasia tissues using atomic absorption spectrophotometer. Unpaired two tailed t test/Mann-Whitney U test and Pearson correlation coefficient were used to compare the level of trace elements, elemental ratios and their interrelations. As compared to benign prostatic tissue, malignant prostatic tissue had significantly lower selenium (p = 0.038) and zinc (p = 0.043) concentrations, a lower zinc/iron ratio (p = 0.04) and positive correlation of selenium with zinc (r = 0.71, p = 0.02) and iron (r = 0.76, p = 0.009). Considerably divergent interrelationship of elements and elemental ratios in prostate cancer versus benign prostatic hyperplasia was noted. Understanding of differential elemental changes and their interdependence may be useful in defining the complex metabolic alterations in prostate carcinogenesis with potential for development of element based newer diagnostic, preventive and therapeutic strategies. Further studies may be needed to elucidate this complex relationship between trace elements and prostate carcinogenesis.

Prostate-specific antigen levels in relation to background factors: are there links to endocrine disrupting chemicals and AhR expression?

BACKGROUND

Prostate-specific antigen (PSA) is a potential biomarker for early detection of prostate cancer (PCa) but its level is known to be affected by many background factors and roles of ubiquitous toxicants have not been determined. Endocrine disrupting chemicals (EDCs) are ubiquitous reproductive toxicants used in consumer products, which promote tumor formation in some reproductive model systems by binding to AhR, but human data on its expression in prostate cancer as well as its association with PSA levels are not clear. This study aimed to evaluate the expression levels of AhR and its association with serological levels of PSA and to detect possible effects of background factors and EDC exposure history on PSA levels in PCa cases.

MATERIALS AND METHODS

A cross-sectional study was conducted on the tissue levels of AhR and serum levels of PSA in 53 PCa cases from 2008-2011 and associations between each and background and lifestyle related factors were determined.

RESULTS

Although the AhR was overexpressed in PCa and correlated with the age of patients, it did not correlate with PSA levels.Of nutritional factors, increased intake of polysaturated fats and fish in the routine regimen of PCa cases increased the PSA levels significantly.

CONCLUSIONS

AhR overexpression in PCa pontws to roles of EDCs in PCa but without any direct association with PSA levels. However, PSA levels are affected by exposure to possible toxicants in foods whichneed to be assessed as possible risk factors of PCa in future studies.