Role of Lipid Peroxidation in the Epidemiology and Prevention of Breast Cancer

Proton pump inhibitors are detrimental to overall survival of patients with glioblastoma: Results from a nationwide real-world evidence database

Background

Proton pump inhibitors (PPIs) are often prescribed to manage corticosteroid-induced gastrointestinal toxicity during glioblastoma (GBM) treatment, but were recently identified as strong inducers of aldehyde dehydrogenase-1A1 (ALDH1A1). ALDH1A1 is a primary metabolic enzyme impacting the outcome of chemotherapy, including temozolomide. High expression of ALDH1A1 is associated with poor prognosis in multiple cancers, suggesting PPIs may have a negative impact on survival.

Methods

Real-world data on GBM patients was annotated from electronic medical records (EMR) according to the prospective observational study, XCELSIOR (NCT03793088). Patients with known IDH1/2 mutations were excluded. Causal effects on survival were analyzed using a multivariate, time-varying Cox Proportional Hazard (CPH) model with stratifications including MGMT methylation status, age, sex, duration of corticosteroid use, extent of resection, starting standard-of-care, and PPI use.

Results

EMR data from 554 GBM patients across 225 cancer centers was collected, with 72% of patients receiving care from academic medical centers. Patients treated with PPIs (51%) had numerically lower median overall survival (mOS) and 2-year OS rates in the total population and across most strata, with the greatest difference for MGMT-methylated patients (mOS 29.2 vs. 40.1 months). In a time-varying multivariate CPH analysis of the above strata, PPIs caused an adverse effect on survival (HR 1.67 [95% CI: 1.15-2.44], P = .007).

Conclusions

Evidence from a nationwide cancer registry has suggested PPIs have a negative impact on OS for GBM patients, particularly those with MGMT promoter methylation. This suggests PPIs should be avoided for prophylactic management of gastrointestinal toxicity in patients with GBM receiving chemoradiotherapy.

Antioxidant Properties of Lippia alba Essential Oil: A Potential Treatment for Oxidative Stress-Related Conditions in Plants and Cancer Cells

Lippia alba (Mill.) N.E.Br. ex Britton and P. Wilson is used in folk medicine of Central and South America for its biological activities: i.e., antifungal, antibacterial, antiviral, and anti-inflammatory. Based on ethnopharmacological information and the increasing interest in this species, this work aimed to test a possible wide use of its essential oil (EO) in pharmaceutical and horticultural applications. Therefore, we focused the attention on the antioxidant activity of the oil as a possible tool to overcome the oxidative stress in both applications. For this purpose, we have chosen three aggressive breast cancer cell lines and two horticultural species (Solanum lycopersicum L. and Phaseolus acutifolius L.) that are very sensitive to salt stress. We determined the antioxidant activity of L. alba EO through the quantification of phenols and flavonoids. Regarding tomato and bean plants under salt stress, L. alba EO was used for the first time as a seed priming agent to enhance plant salt tolerance. In this case, the seed treatment enhanced the content of phenolic compounds, reduced power and scavenger activity, and decreased membrane lipid peroxidation, thus mitigating the oxidative stress induced by salt. While in breast cancer cells the EO treatment showed different responses according to the cell lines, i.e., in SUM149 and MDA-MB-231 the EO decreased proliferation and increased antioxidant activity and lipid peroxidation, showing high cytotoxic effects associated with the release of lactate dehydrogenase, vice versa no effect was observed in MDA-MB-468. Such antioxidant activity opens a new perspective about this essential oil as a possible tool to counteract proliferation in some cancer cell lines and in horticulture as a seed priming agent to protect from oxidative damage in crops sensitive to salinity.

Red Blood Cell Polyunsaturated Fatty Acids and Mortality Following Breast Cancer

BACKGROUND

Intake of polyunsaturated fatty acids (PUFA) may affect mortality following breast cancer; however, epidemiological studies have relied on the self-reported assessment of PUFA intake. Herein, we examined the associations between red blood cell (RBC) PUFAs and mortality.

METHODS

This nested case-control study included 1,104 women from the Women's Healthy Eating and Living study, a multistate randomized controlled trial. Cases (n = 290) comprised women who died from 1995 to 2006. Matched controls (n = 814) comprised women who were alive at the end of follow-up. PUFAs were measured in baseline RBC samples and included four ω-3 and seven ω-6 PUFAs. We examined each PUFA individually and principal components factor analysis (PCFA)-derived scores in association with all-cause mortality (ACM) and breast cancer-specific mortality (BCM) using conditional logistic regression to estimate ORs and 95% confidence intervals (CIs).

RESULTS

In fully adjusted models, ACM ORs were elevated among women with PUFAs above the median  (>median) versus at the median or below (≤median) for α-linolenic acid (ALA; OR = 1.63, 95% CI, 1.18-2.24) and linolenic acid (LA; OR = 1.56, 95% CI, 1.16-2.09). BCM ORs were elevated for ALA (OR = 1.83, 95% CI, 1.27-2.63), LA (OR = 1.70, 95% CI, 1.23-2.37), and γ-linolenic acid (GLA; OR = 1.50, 95% CI, 1.04-2.16). PCFA Factor 1 (arachidonic acid-adrenic acid-docosapentaenoic acid) scores above the median (vs. ≤median) were associated with lower odds of ACM (OR = 0.71, 95% CI, 0.52-0.97) and BCM (OR = 0.69, 95% CI, 0.49-0.97). PCFA Factor 4 (ALA/GLA) scores above the median (vs. ≤median) were associated with increased odds of BCM (OR = 1.47, 95% CI, 1.04-2.09).

CONCLUSIONS

RBC ALA, LA, and GLA may be prognostic indicators among breast cancer survivors.

IMPACT

These results are important for understanding the associations between a biomarker of PUFA intake and mortality among BC survivors.

Metformin and Aspirin: Anticancer effects on A549 and PC3 cancer cells and the mechanisms of action

Metformin exerts its anticancer effect through two mechanisms, directly affecting the tumor and indirectly reducing systemic insulin levels. The anticancer effects of aspirin occur by inhibiting Cyclooxygenase (COX)-2. COX-2 is absent in many cell types under normal conditions and increases under pathological conditions such as cancer. This study aims to investigate the effect of metformin and aspirin and their combination of them on A549 and PC3 cell lines. Metformin and aspirin were investigated separately and in combination on two cancer cell lines, A549 and PC3. The examined groups include the negative control of untreated cells and the positive control of cisplatin and drugs at concentrations of 15, 10, and 20 μg/ mL to investigate the mechanism of oxidative stress factors (reactive oxygen species, lipid peroxidation, Glutathione (GSH)) and apoptosis (lactate dehydrogenase). The results showed that aspirin, metformin, and their combination could affect cancer cell growth by damaging mitochondria, releasing reactive oxygen species, and activating the oxidative stress pathway. Also, these two drugs show the activation of the apoptotic pathway in cancer cells by increasing the lactate dehydrogenase factor and releasing it from the cells. By disrupting the balance of oxidants and antioxidants in the cell, metformin and aspirin cause an increase in the level of reactive oxygen species and a decrease in the level of glutathione reserves, followed by an increase in the level of lipid peroxidation and a decrease in cell viability. Unlike common chemotherapy drugs, these drugs have no known severe side effects; Therefore, in the not-so-distant future, these drugs can also be used as anticancer drugs.

Highlights

Metformin and aspirin, commonly used drugs for diabetes and inflammation, inhibit the growth of cancer cell lines, A549 and PC3.Metformin and aspirin, either separately or in combination, can potentially impede cancer cell growth by disrupting mitochondrial function, inducing the release of reactive oxygen species (ROS), and activating oxidative stress pathways.Furthermore, these drugs can trigger apoptosis, a programmed cell death mechanism, in cancer cells by increasing lactate dehydrogenase (LDH) levels and facilitating its release from the cells.

Online Home-Based Physical Activity Counteracts Changes of Redox-Status Biomarkers and Fitness Profiles during Treatment Programs in Postsurgery Female Breast Cancer Patients

Breast cancer (BC) is one of the most commonly diagnosed types of cancer in women. Oxidative stress may contribute to cancer etiology through several mechanisms. A large body of evidence indicates that physical activity (PA) has positive effects on different aspects of BC evolution, including mitigation of negative effects induced by medical treatment. With the aim to verify the capacity of PA to counteract negative effects of BC treatment on systemic redox homeostasis in postsurgery female BC patients, we have examined the modulation of circulating levels of oxidative stress and inflammation markers. Moreover, we evaluated the impacts on physical fitness and mental well-being by measuring functional parameters, body mass index, body composition, health-related quality of life (QoL), and fatigue. Our investigation revealed that PA was effective in maintaining plasma levels of superoxide dismutase (SOD) activity and tGSH, as well as peripheral blood mononuclear cells' (PBMCs) mRNA levels of SOD1 and heat-shock protein 27. Moreover, we found a significant decrease in plasma interleukin-6 (≈0.57 ± 0.23-fold change, p < 0.05) and increases in both interleukin-10 (≈1.15 ± 0.35-fold change, p < 0.05) and PBMCs' mRNA level of SOD2 (≈1.87 ± 0.36-fold change, p < 0.05). Finally, PA improves functional parameters (6 min walking test, ≈+6.50%, p < 0.01; Borg, ≈-58.18%, p < 0.01; sit-and-reach, ≈+250.00%, p < 0.01; scratch right, ≈-24.12%, and left, ≈-18.81%, p < 0.01) and body composition (free fat mass, ≈+2.80%, p < 0.05; fat mass, ≈-6.93%, p < 0.05) as well as the QoL (physical function, ≈+5.78%, p < 0.05) and fatigue (cognitive fatigue, ≈-60%, p < 0.05) parameters. These results suggest that a specific PA program not only is effective in improving functional and anthropometric parameters but may also activate cellular responses through a multitude of actions in postsurgery BC patients undergoing adjuvant therapy. These may include modulation of gene expression and protein activity and impacting several signaling pathways/biological activities involved in tumor-cell growth; metastasis; and inflammation, as well as moderating distress symptoms known to negatively affect QoL.

Integrated bioinformatic analysis to understand the association between phthalate exposure and breast cancer progression

Phthalates have been extensively used as plasticizers while manufacturing plastic-based consumer products. Estradiol mimicking properties and association studies suggest phthalates may contribute to breast cancer (BC). We performed an in-silico analysis and functional studies to understand the association between phthalate exposure and BC progression. Search for phthalate-responsive genes using the comparative toxicogenomics database identified 20 genes as commonly altered in response to multiple phthalates exposure. Of the 20 genes, 12 were significantly differentially expressed between normal and BC samples. In BC samples, 9 out of 20 genes showed a negative correlation between promoter methylation and its expression. AHR, BAX, BCL2, CAT, ESR2, IL6, and PTGS2 expression differed significantly between metastatic and non-metastatic BC samples. Gene set enrichment analysis identified metabolism, ATP-binding cassette transporters, insulin signaling, and type II diabetes as highly enriched pathways. The diagnostic assessment based on 20 genes expression suggested a sensitivity and a specificity >0.91. The aberrantly expressed phthalate interactive gene influenced the overall survival of BC patients. Drug-gene interaction analysis identified 14 genes and 523 candidate drugs, including 19 BC treatment-approved drugs. Di(2-ethylhexyl) phthlate (DEHP) exposure increased the growth, proliferation, and migration of MCF-7 and MDA-MB-231 cells in-vitro. DEHP exposure induced morphological changes, actin cytoskeletal remodeling, increased ROS content, reduced basal level lipid peroxidation, and induced epithelial to mesenchymal transition (EMT). The present approach can help to explore the potentially damaging effects of environmental agents on cancer risk and understand the underlined pathways and molecular mechanisms.

Clinical implications of lipid peroxides levels in plasma and tumor tissue in breast cancer patients

Oxidative stress can promote the oxidation of lipoproteins and polyunsaturated fatty acids present in cell membranes; an event known as lipid peroxidation (LPO). LPO has been associated with carcinogenesis and cancer progression, however, its meaning concerning the clinicopathological aspects of human breast cancer is not clear. This study investigated LPO profiles in tumor and plasma samples from breast cancer patients (n = 140) considering their clinicopathological features (age at diagnosis, menopausal status, body mass index, tumor histological grade, tumor size, ki-67 proliferation index, presence of metastasis, chemotherapy response, the molecular subtype of cancer and overall survival status). LPO levels were estimated by tert-butyl hydroperoxide-initiated chemiluminescence. High LPO levels were found regarding poor prognosis parameters as young age at diagnosis (p = 0.006 in tissue), premenopausal patients (p = 0.012 in tissue), high-grade tumors (p = 0.010 in tissue and p = 0.002 in plasma), metastatic disease (p = 0.046 in tissue), chemoresistant tumors (p = 0.041 in tissue), disease relapse (p = 0.018 in tissue and p = 0.009 in plasma) and overall survival status (p = 0.001 in plasma). Our findings point out the clinical meaning of LPO and highlight it as an oxidative stress event linked to poor prognosis and disease aggressiveness in breast cancer patients.

Pancreatic Cancer and the Obesity Epidemic: A Narrative Review

Pancreatic cancer (PC) is one of the most frequent causes of death. It usually affects older individuals with incidence closely approaching mortality due to its early asymptomatic feature and highly metastatic nature. Multiple risk factors such as family history, smoking, and germline mutations are associated with PC development, with obesity being one of the controllable factors. This review article focuses on the compilation of various studies to help establish a correlation between obesity or an increased body mass index and PC development. Hence, in this review, we have summarised multiple biological mechanisms of PC development induced by obesity, including insulin resistance, inflammation, beta-cell dysfunction, and oxidative stress, to prove that their correlation when combined with other factors, such as smoking, alcohol and chronic pancreatitis, may increase its risk. We have also reviewed potential diagnostic and screening techniques, such as evaluating precancerous lesions in high-risk patients and management plans discussing upcoming advances in treatment tactics such as neoadjuvant therapy, to reduce post-operative complications.

Vitamin E Derivative with Modified Side Chain Induced Apoptosis by Modulating the Cellular Lipids and Membrane Dynamics in MCF7 Cells

The vitamin E derivative with side chain modification (TC6OAc) has been shown to possess anticancer activity in our earlier in vivo studies. It was hypothesized that, as Vitamin E (VE) and VE derivative are fat soluble lipophilic molecules, they exert their function by modulating the lipid metabolism and related pathways. This study aimed to evaluate the cellular impact of this VE derivative (2,5,7,8-Tetramethyl-2-(4'-Methyl-3'-Pentenyl)-6-Acetoxy Chromane-TC6OH), using α-tocopherol as a reference compound throughout the experiments. Their effects on the cellular metabolism, the biophysical properties of cellular lipids and the functional characteristics of cells were monitored in human estrogen receptor (ER) positive breast cancer cells. It has been documented that TC6OH treatment induces tumor cell apoptosis by dissipating the mitochondrial membrane potential, modulating the lipid, transportation and degradation as well as downregulating certain anti-apoptotic and growth factor related proteins. Due to resistance of ER positive cells to the established therapies, the findings of this study are of translational value.

Comprehensive Analysis of DNA Adducts Using Data-Independent wSIM/MS2 Acquisition and wSIM-City

A novel software has been created to comprehensively characterize covalent modifications of DNA through mass spectral analysis of enzymatically hydrolyzed DNA using the neutral loss of 2'-deoxyribose, a nearly universal MS2 fragmentation process of protonated 2'-deoxyribonucleosides. These covalent modifications termed DNA adducts form through xenobiotic exposures or by reaction with endogenous electrophiles and can induce mutations during cell division and initiate carcinogenesis. DNA adducts are typically present at trace levels in the human genome, requiring a very sensitive and comprehensive data acquisition and analysis method. Our software, wSIM-City, was created to process mass spectral data acquired by a wide selected ion monitoring (wSIM) with gas-phase fractionation and coupled to wide MS2 fragmentation. This untargeted approach can detect DNA adducts at trace levels as low as 1.5 adducts per 109 nucleotides. This level of sensitivity is sufficient for comprehensive analysis and characterization of DNA modifications in human specimens.

Oxidative Stress in Reproduction: A Mitochondrial Perspective

Mitochondria are fundamental organelles in eukaryotic cells that provide ATP through oxidative phosphorylation. During this process, reactive oxygen species (ROS) are produced, and an imbalance in their concentrations can induce oxidative stress (OS), causing cellular damage. However, mitochondria and ROS play also an important role in cellular homeostasis through a variety of other signaling pathways not related to metabolic rates, highlighting the physiological relevance of mitochondria–ROS interactions. In reproduction, mitochondria follow a peculiar pattern of activation, especially in gametes, where they are relatively inactive during the initial phases of development, and become more active towards the final maturation stages. The reasons for the lower metabolic rates are attributed to the evolutionary advantage of keeping ROS levels low, thus avoiding cellular damage and apoptosis. In this review, we provide an overview on the interplay between mitochondrial metabolism and ROS during gametogenesis and embryogenesis, and how OS can influence these physiological processes. We also present the possible effects of assisted reproduction procedures on the levels of OS, and the latest techniques developed to select gametes and embryos based on their redox state. Finally, we evaluate the treatments developed to manage OS in assisted reproduction to improve the chances of pregnancy.

Evaluation of the Diagnostic and Predicative Values of 8-Iso-Prostaglandin F2α as a Biomarker of Breast Cancer

BACKGROUND

Breast cancer (BC) is a commonly reported cancer that is widely prevalent among women. Its early detection improves patient survival and results in better outcomes. For diagnosis and follow-up care, tumor markers are one of the feasible investigations to be ordered. 8-Iso-prostaglandin F2α (8-iso-PGF2α) serves as a serum marker reflecting oxidative stress and subsequent damaging of DNA. In the present study, we aimed to evaluate both diagnostic and predictive values of 8-iso-PGF2α in BC patients.

MATERIALS AND METHODS

Serum levels of 8-iso-PGF2α were assessed for 66 women with benign breast tumors and 65 women who had malignant BC. To compare the patients who had breast tumors with healthy individuals, 63 women free of breast diseases were selected as controls.

RESULTS

The serum level of 8-iso-PGF2α in the BC patients (57.92 pg/mL) was significantly higher compared to those with benign tumors (18.89 pg/mL) (p < 0.001). In addition, individuals with no breast diseases had less 8-iso-PGF2α (4.02 pg/mL) compared to those who had developed a tumor (p < 0.001). Serum 8-iso-PGF2α was found to be positively correlated with both carcinoembryonic antigen (r = 0.74, p < 0.001) and cancer antigen 15-3 (r = 0.80, p < 0.001). Furthermore, serum 8-iso-PGF2α showed high diagnostic performance in BC (AUC = 0.999, sensitivity = 100%, specificity = 99.2% at a cutoff value of 36.18 pg/mL).

CONCLUSIONS

Our study found that the high level of serum 8-iso-PGF2α helps to provide a non-invasive indicator to detect BC. Future work with a larger sample size and various phases of BC can confirm the current results which provide insights into the early detection of cancer.

High sensitive detection of circulating tumor cell by multimarker lipid magnetic nanoparticles and clinical verifications

Tumor cells with heterogeneity and diversity can express different markers. At present, positive separation of circulating tumor cells (CTC) taking EpCAM as the marker was used in most cases which could be one-sided, while this study successfully prepared four antibody-modified magnetic immunoliposomes (MIL) by using the self-assembled liposome with antibody derivatives. This study aims to explore the separation efficiency and clinical detection feasibility of single or combined use of MIL with multi-tumor markers on different tumors. Captured CTC were stained with CK-FITC, CD45-PE and DAPI, and fluorescence microscope was used for the observation, analysis and calculation. The result indicated that the CTC number positive rate in blood samples of four different magnetic balls on the same patient could be up to 87.5% in 32 patients with 14 different kinds tumors. While the effect of directly mixed separation by four kinds of magnetic balls was not satisfying. It suggested that the MIL of multi-tumor markers could be a powerful tool for CTC separation in application of tumor screening and prognosis.

Resveratrol Action on Lipid Metabolism in Cancer

Cancer diseases have the leading position in human mortality nowadays. The age of oncologic patients is still decreasing, and the entire scientific society is eager for new ways to fight against cancer. One of the most discussed issues is prevention by means of natural substances. Resveratrol is a naturally occurring plant polyphenol with proven antioxidant, anti-inflammatory, and anticancer effects. Tumor cells display specific changes in the metabolism of various lipids. Resveratrol alters lipid metabolism in cancer, thereby affecting storage of energy, cell signaling, proliferation, progression, and invasiveness of cancer cells. At the whole organism level, it contributes to the optimal metabolism extent with respect to the demands of the organism. Thus, resveratrol could be used as a preventive and anticancer agent. In this review, we focus on some of the plethora of lipid pathways and signal molecules which are affected by resveratrol during carcinogenesis.

Flaxseed extract induces apoptosis in human breast cancer MCF-7 cells

Significant evidence indicated that flaxseed (Linum usitatissimum) possesses various positive health aspects such as reducing the risk of cancer and cardiovascular diseases. The fatty acids are considered to be responsible for these benefits of flaxseed. Herein, the in vitro effects of flaxseed extract on the growth and apoptosis of human breast cancer MCF-7 cells were investigated. The MCF-7 cells treated with flaxseed extract showed a dose-dependent decrease in cell viability. The flaxseed extract induced reactive oxygen species and the flow cytometric analysis demonstrated that flaxseed fatty acids triggered apoptosis of MCF-7 cells, which was also shown by the loss of mitochondrial membrane potential and caspase cascade reaction. Thus, the flaxseed extract regulated the growth of MCF-7 cells and induced apoptosis. Eventually, the flaxseed could be used as a dietary supplement to prevent breast cancer.

Oxidative Stress and Anti-oxidants in Pre and Post-operative Cases of Breast Carcinoma

Objectives

To investigate the existence of oxidative stress in the sera of patients with breast cancer and its effects on the consequent breast cancer.

Materials and Methods

This study included 50 control volunteers, 50 patients with breast cancer, and 50 patients with post-operative breast cancer. Patients with pre-operative cancer were clinically and histopathologically diagnosed for breast carcinoma with stage 0, not having therapeutic history. The control 50 healthy female volunteers had the same socio-economic status, and no history of any cancer. After obtaining consent, venous blood was collected from the volunteers by vein puncture using a 10 mL sterile disposable syringe and needle. About 8 mL of blood was collected, 4 mL of which was poured into a heparinized bulb and 4 mL was allowed to clot. The levels of MDA, NO, GSH, and activities of RBC-SOD (in RBC lysate), NOS, copper and zinc GPx, and CAT, and vitamins A, C, and E metabolites were measured in the sera of each group.

Results

The activities of RBC-SOD and the levels of MDA, NO, as well as the NOS were significantly higher in the sera of all patients with breast cancer as compared with the controls. However, the levels of GSH and vitamins A, C, and E, as well as the activities of copper and zinc GPx and CAT were decreased in patients with breast cancer when compared with the controls.

Conclusion

The study provides further evidence for the presence of oxidative stress in the serum of patients with breast carcinoma. Patients with higher levels of MDA showed deficiencies of antioxidants and trace elements in the serum. A poor dietary antioxidant status and high oxidant levels are associated with the risk of breast cancer, thus suggesting that patients with breast cancer should take nutritive supplements to balance the antioxidant and oxidant levels for better outcomes.

NF-kappaB Regulates Redox Status in Breast Cancer Subtypes

Oxidative stress (OS) is an indispensable condition to ensure genomic instability in cancer cells. In breast cancer (BC), redox alterations have been widely characterized, but since this process results from a chain of inflammatory events, the causal molecular triggers remain to be identified. In this context, we used a microarray approach to investigate the role of the main pro-oxidant transcription factor, nuclear factor-kappa B (NF-κB), in gene profiles of BC subtypes. Our results showed that NF-κB knockdown in distinct BC subtypes led to differential expression of relevant factors involved in glutathione metabolism, prostaglandins, cytochrome P450 and cyclooxygenase, suggesting a relationship between the redox balance and NF-κB in such cells. In addition, we performed biochemical analyses to validate the microarray dataset focusing on OS and correlated these parameters with normal expression or NF-κB inhibition. Our data showed a distinct oxidative status pattern for each of the three studied BC subtype models, consistent with the intrinsic characteristics of each BC subtype. Thus, our findings suggest that NF-κB may represent an additional mechanism related to OS maintenance in BC, operating in various forms to mediate other important predominant signaling components of each BC subtype.

Association between CYP17 T-34C rs743572 and breast cancer risk

Association between CYP17 T-34C (rs743572) polymorphism and breast cancer (BC) risk was controversial. In order to derive a more definitive conclusion, we performed this meta-analysis. We searched in the databases of PubMed, EMBASE and Cochrane for eligible publications. Pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were used to assess the strength of association between CYP17 T-34C polymorphism and breast cancer risk. Forty-nine studies involving 2,7104 cases and 3,4218 control subjects were included in this meta-analysis. In overall, no significant association between CYP17 T-34C polymorphism and breast cancer susceptibility was found among general populations. In the stratified analysis by ethnicity and source, significant associations were still not detected in all genetic models; besides, limiting the analysis to studies with controls in agreement with HWE, we also observed no association between CYP17 T-34C polymorphism and breast cancer risk. For premenopausal women, we didn't detect an association between rs743572 and breast cancer risk; however, among postmenopausal women, we observed that the association was statistically significant under the allele contrast genetic model (OR = 1.10, 95% CI = 1.03-1.17, P = 0.003), but not in other four models. In conclusion, rs743572 may increase breast cancer risk in postmenopausal individuals, but not in premenopausal folks and general populations.

Effect of Cruciferous Vegetable Intake on Oxidative Stress Biomarkers: Differences by Breast Cancer Status

This post hoc analysis examined cruciferous vegetable intake on urinary oxidative metabolites in postmenopausal women. Intervention participants (n = 69) received cruciferous vegetables (≥14 cups/week) during a 3-week period. First morning urine measured 8-isoprostane and 8-hydroxy-2'-deoxyguanosine. Dietary intake was estimated using 24-h recalls. When stratified by history of breast cancer, those with breast cancer had significantly lower post-intervention urinary 8-hydroxy-2'-deoxyguanosine values in the intervention arm versus. the control arm (1.1 ng/mL vs. 3.2 ng/mL, p = .01) after adjustment for baseline 8-hydroxy-2'-deoxyguanosine. This was not observed in those without breast cancer. Further work is needed to understand the role of breast cancer in these relationships.

Effects of exercise on markers of oxidative stress: an Ancillary analysis of the Alberta Physical Activity and Breast Cancer Prevention Trial

BACKGROUND

Oxidative stress may contribute to cancer aetiology through several mechanisms involving damage to DNA, proteins and lipids leading to genetic mutations and genomic instability. The objective of this study was to determine the effects of aerobic exercise on markers of oxidative damage and antioxidant enzymes in postmenopausal women.

METHODS

The Alberta Physical Activity and Breast Cancer Prevention Trial (ALPHA) was a two-centre, two-armed randomised trial of 320 inactive, healthy, postmenopausal women aged 50-74 years. Participants were randomly assigned to a year-long exercise intervention (225 min/week) or a control group while being asked to maintain a normal diet. Fasting blood samples were obtained and plasma concentrations of two oxidative damage markers (8-hydroxy-2'-deoxyguanosine (8-OHdG) and 8-isoprostaglandin F2α (8-Iso-PGF2α)) and two antioxidant enzymes (superoxide dismutase and catalase) were measured at baseline, 6 months and 12 months. Intention-to-treat (ITT) and per-protocol analyses were performed using linear mixed models adjusted for baseline biomarker concentrations. A further exercise adherence analysis, based on mean minutes of exercise per week, was also performed.

RESULTS

In the ITT and per-protocol analyses, the exercise intervention did not have any statistically significant effect on either oxidative damage biomarkers or antioxidant enzyme activity.

CONCLUSIONS

A year-long aerobic exercise intervention did not have a significant impact on oxidative stress in healthy, postmenopausal women.

TRIAL REGISTRATION NUMBER

NCT00522262.

Anti-cancer effect of Annona Muricata Linn Leaves Crude Extract (AMCE) on breast cancer cell line

Background

Annona muricata Linn which comes from Annonaceae family possesses many therapeutic benefits as reported in previous studies and to no surprise, it has been used in many cultures to treat various ailments including headaches, insomnia, and rheumatism to even treating cancer. However, Annona muricata Linn obtained from different cultivation area does not necessarily offer the same therapeutic effects towards breast cancer (in regards to its bioactive compound production). In this study, anti-proliferative and anti-cancer effects of Annona muricata crude extract (AMCE) on breast cancer cell lines were evaluated.

Methods

A screening of nineteen samples of Annona muricata from different location was determined by MTT assay on breast cancer cell lines (MCF-7, MDA-MB-231, and 4 T1) which revealed a varied potency (IC₅₀) amongst them. Then, based on the IC₅₀ profile from the anti-proliferative assay, further downward assays such as cell cycle analysis, Annexin V/FITC, AO/PI, migration, invasion, and wound healing assay were performed only with the most potent leaf aqueous extract (B1 AMCE) on 4 T1 breast cancer cell line to investigate its anti-cancer effect. Then, the in vivo anti-cancer study was conducted where mice were fed with extract after inducing the tumor. At the end of the experiment, histopathology of tumor section, tumor nitric oxide level, tumor malondialdehyde level, clonogenic assay, T cell immunophenotyping, and proteome profiler analysis were performed.

Results

Annona muricata crude extract samples exhibited different level of cytotoxicity toward breast cancer cell lines. The selected B1 AMCE reduced the tumor’s size and weight, showed anti-metastatic features, and induced apoptosis in vitro and in vivo of the 4 T1 cells. Furthermore, it decreased the level of nitric oxide and malondialdehyde in tumor while also increased the level of white blood cell, T-cell, and natural killer cell population.

Conclusion

The results suggest that, B1 AMCE is a promising candidate for cancer treatment especially in breast cancer and deserves further research as an alternative to conventional drugs while also stressed out the selection of soursop sample which plays a significant role in determining its potential therapeutic effect on cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1290-y) contains supplementary material, which is available to authorized users.

Combined Incubation of Cadmium, Docosahexaenoic and Eicosapentaenoic Acid Affecting the Oxidative Stress and Antioxidant Response in Human Hepatocytes In Vitro

Human hepatocellular cells Hep G2 were used to investigate the effects of the intake of contaminated fish on oxidative stress. Uptake of heavy metal contaminated fish was mimicked by incubating the cells with a combination of cadmium chloride (Cd2+) as possible contaminant and a combination of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) as important fatty acids (FA) specific for fish. The main aim of this study was to determine the effects of these co-incubations (FA, Cd2+) on lipid and protein oxidation. In addition we also evaluated the antioxidant response of the cells using two different methods (SOD and TAC). Pre-incubation with the chosen FA significantly reduced the oxidative stress caused by incubation with Cd2+. We measured an increased level of carbonyl proteins (CP) in the cells pre-incubated with bovine serum albumin (BSA) and post-incubated with Cd2+.

Reproductive toxicity in male mice after exposure to high molybdenum and low copper concentrations

To evaluate the effects of dietary high molybdenum (HMo) and low copper (LCu) concentrations on reproductive toxicity of male mice, 80 mice were divided into 4 groups of 20. These groups were fed with the following: (1) normal control (NC) diet (NC group); (2) NC and HMo diets (HMo group); (3) LCu diet (LCu group); and (4) HMo and LCu diets (HMoLCu group). On the 50th and 100th day, superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), and total antioxidant capacity (T-AOC) were analyzed to determine oxidative stress states. Morphological changes in testicular tissue were evaluated with hematoxylin and eosin staining and ultrastructural changes were monitored by transmission electron microscopy. The results showed that administration of HMo, LCu, and HMoLCu not only decreased sperm density and motility but also increased the rate of teratosperm occurrence. A significant increase in MDA content and a decrease in SOD, GSH-Px, and T-AOC contents were observed in LCu, HMo, and HMoLCu groups. Testicular tissues and cells of mice were damaged by HMo and the damages were more serious in the case of Cu deficiency. Exposure to HMo adversely affected the reproductive system of male mice, and dietary LCu plays key roles in HMo-induced reproductive toxicity.

Plasma fluorescent oxidation products and risk of estrogen receptor-negative breast cancer in the Nurses' Health Study and Nurses' Health Study II

Findings from epidemiologic studies of oxidative stress biomarkers and breast cancer have been mixed, although no studies have focused on estrogen receptor-negative (ER-) tumors which may be more strongly associated with oxidative stress. We examined prediagnostic plasma fluorescent oxidation products (FlOP), a global biomarker of oxidative stress, and risk of ER- breast cancer in a nested case-control study in the Nurses' Health Study and Nurses' Health Study II. ER- breast cancer cases (n = 355) were matched to 355 controls on age, month/time of day of blood collection, fasting status, menopausal status, and menopausal hormone use. Conditional logistic regression models were used to examine associations of plasma FlOP at three emission wavelengths (FlOP_360, FlOP_320, and FlOP_400) and risk of ER- breast cancer. We did not observe any significant associations between FlOP measures and risk of ER- breast cancer overall; the RRQ4vsQ1 (95 %CI) 0.70 (0.43-1.13), p trend = 0.09 for FlOP_360; 0.91(0.56-1.46), p trend = 0.93 for FlOP_320; and 0.62 (0.37-1.03), p trend = 0.10 for FlOP_400. Results were similar in models additionally adjusted for total carotenoid levels and in models stratified by age and total carotenoids. Although high (vs. low) levels of FIOP_360 and FIOP_400 were associated with lower risk of ER- breast cancer in lean women (body mass index (BMI) < 25 kg/m(2)) but not in overweight/obese women, these differences were not statistically significant (pint = 0.23 for FlOP_360; pint = 0.37 for FlOP_400). Our findings suggest that positive associations of plasma FlOP concentrations and ER- breast cancer risk are unlikely.

Serum Oxidative Stress Markers and Genotoxic Profile Induced by Chemotherapy in Patients with Breast Cancer: A Pilot Study

The aim of this study was to evaluate the oxidative parameters of erythrocytes and genotoxicity in leukocytes of patients with breast cancer. Oxidative parameters were detected by spectrophotometry and genotoxic damage by single cell gel electrophoresis. Twenty-eight women with breast cancer were monitored before chemotherapy and after the second and fourth cycles of therapy with cyclophosphamide and doxorubicin. After the fourth cycle, increases (P < 0.05) in the reactive substances to thiobarbituric acid levels, nitrite content, and superoxide dismutase activity and high rates of DNA damage in leukocytes were observed when compared with healthy women group and baseline levels. Similarly, after the second cycle, the same parameters were increased (P < 0.05) when compared with baseline levels. Increase in catalase activity was detected only after the fourth cycle and reduced glutathione levels and glutathione peroxidase activity were decreased in all cycles when compared with healthy women, as well as after the second and fourth chemotherapy cycles compared to baseline (P < 0.05). Patients with breast cancer presented an indicative of oxidative stress before, during, and after chemotherapy, as well as increased genotoxic damage in all stages of treatment, demonstrating the clinical applicability of this investigation.

The effect of physical training on the N-methyl-N-nitrosourea-induced mammary carcinogenesis of Sprague-Dawley rats

The impact of physical activity on carcinogenesis has been demonstrated in many studies. Taking into account the discrepant results of physical exercise on the cell proliferation and apoptosis of breast cancer, we aimed to examine the impact of physical training on N-methyl-N-nitrosourea-(MNU)-induced mammary carcinogenesis. Fifty female rats were divided into four groups according to the intensity of physical activity they undertook. The number of developed tumors, tumor volume, and histopathological diagnoses were noted. Apoptosis and cell proliferation were studied by the number of TUNEL-positive and Ki-67-expressing cells. We demonstrated a statistically significant decrease in the tumor number between all trained groups and the control group. The results were most pronounced in the group with a moderate intensity of training. Moreover, we showed a decrease in tumor volume as training intensity increased, though the differences were not statistically significant. The mean number of TUNEL-positive cancer cells was significantly higher in the training groups than in the control group. These data suggest that physical training, especially of moderate intensity, may alleviate MNU-induced mammary carcinogenesis. The results could suggest that physical exercise-induced apoptosis may be a protective mechanism.

Trastuzumab-based chemotherapy modulates systemic redox homeostasis in women with HER2-positive breast cancer

Trastuzumab is an immunotargeting therapeutic against breast tumors with amplification of the human epithelial growth factor receptor 2 (HER2). HER2 patients naturally exhibit disruption in the pro-oxidant inflammatory profiling; however, the impact of trastuzumab-based chemotherapy in modulating this process is still unknown. Here we determined the systemic pro-inflammatory profile of women diagnosed with HER2-amplified tumors, undergoing trastuzumab-based chemotherapy (TZ), and compared the results with that of healthy controls (CTR) and untreated patients with HER2-amplified breast cancer (CA). The plasmatic inflammatory profile was assessed by evaluating pro-oxidant parameters such as lipid peroxidation, total antioxidant capacity (TRAP), levels of advanced oxidation protein products (AOPPs), nitric oxide (NO), C-reactive protein (CRP), and total thiol content. Markers of cardiac damage were also assessed. Our findings showed increased NO levels in TZ than that in either CA or CTR groups. Furthermore, TZ augmented TRAP and reduced total thiol than that of the CA group. Our data also revealed that AOPP levels were significantly higher in the TZ than the CA group. AOPP and the MB fraction of creatine-kinase (CKMB) levels were positively correlated in TZ patients. These findings suggest that trastuzumab-associated chemotherapy can modulate the pro-inflammatory markers of HER2-positive breast cancer patients to the levels found in healthy controls.

Blighia sapida leaves halt elevated blood glucose, dyslipidemia and oxidative stress in alloxan-induced diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Blighia sapida leaves are used in the management of diabetes in Nigeria. Thus the antidiabetic activity of methanolic Blighia sapida leaf extract and its capability to halt oxidative stress and dyslipidemia in alloxan-induced diabetic rats were investigated.

METHODS

In vitro antioxidant activity of the extract (0.2-1.0mg/mL) was investigated using 2,2-diphenyl-1-1picrylhydrazyl (DPPH) radical, superoxide ion, hydrogen peroxide, and hydroxyl radical and ferric ion reducing system. Antidiabetic was evaluated in alloxan-induced diabetic rats.

RESULTS

The methanolic extract of Blighia sapida leaves at 1.0mg/mL scavenged DPPH, superoxide ion, hydrogen peroxide, and hydroxyl radical at 80.34%, 57.39%, 72.36% and 77.0% respectively, while ferric ion was significantly reduced. Single oral dose of the extract significantly reduced blood glucose level in a dose dependent manner with highest dose producing 18.6% reduction after 240min. Similar reduction was produced after 28 days of extract administration with the highest dose producing 65.65% reduction which compared significantly (P<0.05) with the control group and glibenclamide treated groups. Alloxan-induced diabetic mediated alterations in liver and serum cholesterol, triacylglycerides, high-density lipoprotein cholesterol (HDLc), low density lipoprotein (LDL) cholesterol and very low-density lipoprotein cholesterol (VLDLc) were significantly (P<0.05) restored by the extract. Methanolic extract of Blighia sapida leaves significantly attenuated the decrease in the activities of reactive oxygen species detoxifying enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose 6-phosphate dehydrogenase) in the liver and pancreas of alloxan-induced diabetic rats. Elevation in the concentrations of malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl, and fragmented DNA was significantly (P<0.05) lowered by Blighia sapida leaves extract.

CONCLUSION

Overall, methanolic extract of Blighia sapida leaves at all doses used reduced blood glucose level and prevented oxidative stress and dyslipidemia in alloxan-induced diabetic rats.

Impact of tumor removal on the systemic oxidative profile of patients with breast cancer discloses lipid peroxidation at diagnosis as a putative marker of disease recurrence

BACKGROUND

Recent studies have suggested a regulatory role for some of the metabolites derived from oxidative stress in breast cancer. In this way, cancer-induced oxidative changes could modify the breast environment and potentially trigger systemic responses that may affect disease prognosis and recurrence. In this study, we investigated the systemic oxidative profile of women with early breast cancer bearing the primary tumor and after tumor withdrawal, and its long-term implications.

PATIENTS AND METHODS

Plasma samples were collected at diagnosis, and the systemic oxidative profile was determined by evaluating the lipid peroxidation, total antioxidant capacity of plasma (TRAP), malondialdehyde (MDA), protein carbonylation, and hydroperoxides. Nitric oxide, vascular endothelial growth factor (VEGF), and tumor necrosis factor alpha (TNF-α) levels were further measured. We also evaluated the impact of the oxidative profiling at diagnosis on disease recurrence in a 5-year follow-up.

RESULTS

Enhanced oxidative stress was detected in patients bearing the primary tumors, characterized by high lipid peroxidation, TRAP consumption, high carbonyl content, and elevated VEGF and TNF-α levels. After tumor removal, the systemic oxidative status presented attenuation in lipid peroxidation, MDA, VEGF, and TNF-α. The 5-year recurrence analysis indicated that all patients who recidivated presented high levels of lipid peroxidation measured by chemiluminescence at diagnosis.

CONCLUSIONS

Our data suggest that the presence of the primary tumor is indicative of the systemic pro-oxidant status of breast cancer and demonstrates a role for lipid peroxidation in disease recurrence, highlighting the need for a metabolic follow-up of patients with cancer at diagnosis before tumor removal.

Exercício de força associado a óleo de peixe reduzem massa tumoral e caquexia em ratos

OBJETIVO: Investigar o efeito do treinamento de salto associado à suplementação com óleo de peixe (1g/kg peso corporal/dia) em ratos portadores do tumor de Walker 256, sobre parâmetros bioquímicos de caquexia e crescimento tumoral.MÉTODOS: Oitenta Ratos foram divididos em sedentário sem ou com tumor (S ou SW), exercitado (EX ou EXW), suplementado com óleo de peixe (SO ou SWO) e suplementado e exercitado (EXO ou EXWO). Sessões de treinamento de salto consistiram de 10 séries com duração de 30 segundos e intervalo de 1 minuto entre cada série. Após seis semanas de treinamento, células do tumor de Walker 256 foram inoculadas e após 15 dias os animais foram mortos.RESULTADOS: O peso médio do tumor no grupo SW foi de 25,32 g, p<0,05 vs. ao dos SWO, EXW e EXWO (~11 g). O grupo SW apresentou hipoglicemia, hiperlactatemia, hipertriacilglicerolemia e perda de peso (-7,52±3,19g), caracterizando estado caquético. Suplementação com óleo de peixe (SWO), exercício (EXW) e associação de ambos (EXWO) impediram a instalação da caquexia (p<0,05 vs. SW). No grupo SWO, EXW e suas associações (EXWO) promoveram ganho de peso (p<0,05 vs. SW), mas inferior ao da suplementação isolada (p<0,05 vs. SWO). A proliferação celular in vitro das células tumorais foi menor no grupo SWO (p<0,05 vs. SW) e o exercício reduziu ainda mais (p<0,05 vs. SW e SWO), não havendo incremento quando se associaram ambas as terapias. Lipoperoxidação (p<0,05) foi maior nos SWO, EXW, EXWO vs. S. A expressão de Bcl-2 foi menor também nestes grupos vs. SW.CONCLUSÕES: O treinamento de força e a suplementação com óleo de peixe foram eficazes em evitar a caquexia e induzir a redução do crescimento tumoral, da proliferação tumoral e expressão de Bcl-2, mas a associação de ambos não promoveu efeito aditivo.

Urinary biomarkers of oxidative stress and breast cancer survival

PURPOSE

Systemic oxidative stress has been implicated in the pathogenesis and progression of many chronic diseases, including breast cancer. No studies have investigated F2-isoprostanes (F2-IsoPs), valid biomarkers of systemic oxidative stress, in association with breast cancer prognosis. We conducted a nested case-control study in a prospective breast cancer survivor cohort to investigate systemic oxidative stress and survival.

METHODS

Urinary levels of F2-IsoPs and its major urinary metabolite (2,3-dinor-5,6-dihydro-15-F2t-IsoP, F2-IsoP-M) were measured post-cancer treatment using gas chromatography/negative ion chemical ionization mass spectrometry for 57 deceased breast cancer patients (cases) and 103 surviving patients (controls) matched 1:2 on age at diagnosis, stage, and diagnosis year. Odds ratios (ORs) and 95 % confidence intervals (CIs) were derived from conditional logistic regression models.

RESULTS

In unadjusted models, elevated F2-IsoP levels categorized based on the median value [≥1.73; <1.73 (reference)] were nonsignificantly inversely associated with mortality (OR 0.51, 95 % CI 0.24-1.10). After adjustment for potential confounders, elevated F2-IsoP levels were significantly associated with mortality (OR 0.36, 95 % CI 0.14-0.96). The inverse association was marginally significant when F2-IsoP was categorized based on tertiles (p trend = 0.08). In contrast, elevated F2-IsoP-M levels, categorized based on the median level [≥0.91; < 0.91(reference)], were associated with a statistically nonsignificant increased risk of mortality in both unadjusted and adjusted models (adjusted OR 1.39, 95 % CI 0.62-3.09).

CONCLUSION

Results suggest a role for oxidative stress biomarkers in breast cancer survival; however, as this is the first study to date, additional larger studies are needed.

EGCG inhibits Cd(2+)-induced apoptosis through scavenging ROS rather than chelating Cd(2+) in HL-7702 cells

CONTEXT AND OBJECTIVE

Epigallocatechin-3-gallat (EGCG), the major catechin in green tea, shows a potential protective effect against heavy metal toxicity to humans. Apoptosis is one of the key events in cadmium (Cd(2+))-induced cytotoxicity. Nevertheless, the study of EGCG on Cd(2+)-induced apoptosis is rarely reported. The objective of this study was to clarify the effect and detailed mechanism of EGCG on Cd(2+)-induced apoptosis.

METHODS

Normal human liver cells (HL-7702) were treated with Cd(2+) for 21 h, and then co-treated with EGCG for 3 h. Cell viability, apoptosis, intracellular reactive oxygen species (ROS), malondialdehyde (MDA), mitochondrial membrane potential (MMP) and caspase-3 activity were detected. On the other hand, the chelation of Cd(2+) with EGCG was tested by UV-Vis spectroscopy analysis and Nuclear Magnetic Resonance ((1)H NMR) spectroscopy under neutral condition (pH 7.2).

RESULTS AND CONCLUSION

Cd(2+) significantly decreased the cell viability and induced apoptosis in HL-7702 cells. Conversely, EGCG co-treatment resulted in significant inhibition of Cd(2+)-induced reduction of cell viability and apoptosis, implying a rescue effect of EGCG against Cd(2+) poisoning. The protective effect most likely arises from scavenging ROS and maintaining redox homeostasis, as the generation of intracellular ROS and MDA is significantly reduced by EGCG, which further prevents MMP collapse and suppresses caspase-3 activity. However, no evidence is observed for the chelation of EGCG with Cd(2+) under neutral condition. Therefore, a clear conclusion from this work can be made that EGCG could inhibit Cd(2+)-induced apoptosis by acting as a ROS scavenger rather than a metal chelating agent.

EPA, an omega-3 fatty acid, induces apoptosis in human pancreatic cancer cells: role of ROS accumulation, caspase-8 activation, and autophagy induction

In a recent study, we showed that eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two common omega-3 fatty acids, can cause ROS accumulation and subsequently induce caspase-8-dependent apoptosis in human breast cancer cells (Kang et al. [2010], PLoS ONE 5: e10296). In this study, we showed that the pancreas has a unique ability to accumulate EPA at a level markedly higher than several other tissues analyzed. Based on this finding, we sought to further investigate the anticancer actions of EPA and its analog DHA in human pancreatic cancer cells using both in vitro and in vivo models. EPA and DHA were found to induce ROS accumulation and caspase-8-dependent cell death in human pancreatic cancer cells (MIA-PaCa-2 and Capan-2) in vitro. Feeding animals with a diet supplemented with 5% fish oil, which contains high levels of EPA and DHA, also strongly suppresses the growth of MIA-PaCa-2 human pancreatic cancer xenografts in athymic nude mice, by inducing oxidative stress and cell death. In addition, we showed that EPA can concomitantly induce autophagy in these cancer cells, and the induction of autophagy diminishes its ability to induce apoptotic cell death. It is therefore suggested that combination of EPA with an autophagy inhibitor may be a useful strategy in increasing the therapeutic effectiveness in pancreatic cancer.

Effects of open versus laparoscopic nephrectomy techniques on oxidative stress markers in patients with renal cell carcinoma

The aim of the study was to determine the concentration of lipid peroxidation products, the activity of selected antioxidant and lysosomal enzymes, and protease inhibitor in patients with renal cell carcinoma who underwent radical nephrectomy. The studied group included 44 patients: 21 of them underwent open surgery, while 23 underwent laparoscopy. Blood samples were collected three times: before treatment and 12 hours and five days after nephrectomy. In blood of participants, the concentration of thiobarbituric acid reactive substances (TBARS), the activity of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx), and the activity of acid phosphatase (AcP), arylsulfatase (ASA), cathepsin D (CTSD), and α 1-antitrypsin (AAT) were assayed. No statistically significant differences in investigated parameters were found between studied groups. Moreover, TBARS concentration and CAT, SOD, and GPx activity were not altered in the course of both types of surgery. Five days after both open and laparoscopic nephrectomy techniques, AAT activity was higher than its activity 12 hours after the procedure. The obtained results suggest that laparoscopy may be used for nephrectomy as effectively as open surgery without creating greater oxidative stress. Reduced period of convalescence at patients treated with laparoscopy may be due to less severe response of acute-phase proteins.

LC-MS/MS Determination of Isoprostanes in Plasma Samples Collected from Mice Exposed to Doxorubicin or Tert-Butyl Hydroperoxide

Isoprostanes are stable products of arachidonic acid peroxidation and are regarded as the most reliable markers of oxidative stress in vivo. Here we describe the LC-MS/MS procedure enabling simultaneous determination of four regioisomers (8-iso prostaglandin F2α, 8-iso-15(R)-prostaglandin F2α, 11β-prostaglandin F2α, 15(R)-prostaglandin F2α) in plasma samples collected from mice. The four plasma isoprostanes are determined by LC-ESI-MS/MS with deuterated 8-iso-PGF2α-d4 as an internal standard (I.S.). For plasma samples spiked with the isoprostanes at a level of 200 pg/mL each, the method imprecision has been below 7.1% and mean inaccuracy equaled 8.7%. The applicability of the proposed approach has been verified by the assessment of changes in isoprostane levels in plasma samples derived from mice exposed to tert-butyl hydroperoxide (TBHP), a model inducer of oxidative stress, or to antitumor drug doxorubicin (DOX) known for potent stimulation of redox cycling. Compared to the control group of mice, both oxidative stress inducers tested increased the levels of three out of four isoprostanes in exposed animals; 11β-prostaglandin F2α being the exception. The greatest rise was observed in the case of 15(R)-prostaglandin F2α, by about 50% and 70% in plasma samples derived from mice exposed to DOX and TBHP, respectively.

Oxidative stress associated to dysfunctional adipose tissue: a potential link between obesity, type 2 diabetes mellitus and breast cancer

Diabetes mellitus and breast cancer are two important health problems. Type 2 diabetes (T2DM) and obesity are closely linked with both being associated with breast cancer. Despite abundant epidemiological data, there is no definitive evidence regarding the mechanisms responsible for this association. The proposed mechanisms by which diabetes affects breast cancer risk and prognosis are the same as the mechanisms hypothesised for the contribution of obesity to breast cancer risk. The obesity-induced inflammation promoted by adipose tissue dysfunction is a key feature, which is thought to be an important link between obesity and cancer. Inflammation induces an increase in free radicals and subsequently promotes oxidative stress, which may create a microenvironment favourable to the tumor development in obese persons. Oxidative stress is also proposed as the link between obesity and diabetes mellitus. Therefore, obesity-related oxidative stress could be a direct cause of neoplastic transformation associated with obesity and T2DM in breast cancer cells. This review is focused on the role of obesity-related oxidative stress in the context of chronic inflammation, on the time of breast cancer onset and progression, which provide targets for preventive and therapeutic strategies in the fields of diabetes and obesity-related breast cancer.

Change in adiponectin and oxidative stress after modifiable lifestyle interventions in breast cancer cases

BACKGROUND

Breast cancer is one of the most frequent diseases in women today. Little information exists on modifiable lifestyle factors including effects of ginger supplements (as an anti-oxidant and anti-inflammatory herbal) and water-based exercise on biomarkers related to oxidative stress such as malondialdehyde (MDA), nitric oxide (NO) and glutathione peroxidase (GPx) and adiponectin in obese women with breast cancer. The aim of this study was to determine the single and concomitant effect of 6-wks water-based exercise and oral ginger supplement on the aforesaid markers in obese women with breast cancer.

MATERIALS AND METHODS

Forty women diagnosed with breast cancer (48 ± 5.4 years, 76 ± 9 kg, fat mass 41.8 ± 4%), volunteered to participate in the study. Subjects were randomly assigned into four groups; placebo, water-based exercise, ginger supplement and water-based exercise+ginger supplement groups. Subjects in the ginger supplement group and the water-based exercise+ginger supplement group orally received 4 capsules (each capsule contained 750 mg), 7 days a week for 6 weeks. The water-based exercise program featured progressive increase in intensity and time, ranging from 50% to 75% of heart rate reserve, in a pool with 15 meters width, 4 times a week for 6 weeks. Fasting blood samples were collected at pre-test and post-test time points.

RESULTS

The ginger supplementation and or the water-base exercise resulted in an increase of adiponectin, NO and GPx and reduction MDA, as compared to pre-test values. However, the combined intervention (water-base exercise and ginger supplement) group showed significantly a far better effect on the biomarkers related to oxidative stress and adiponectin levels, as compared to the water- base exercise or ginger supplement alone groups and the age-matched placebo group.

CONCLUSIONS

Our results revealed that water-base exercise is a non-drug therapeutic strategy to reduce systemic stress in obese women suffering from breast cancer. Further, ginger supplementation alone or in combination with training, also play an important role in the pathogenesis of oxidative stress in obese women diagnosed with breast cancer.

Aldehyde dehydrogenase 1A1--a new mediator of resistance to temozolomide in glioblastoma

Implementation of chemotherapy with the drug temozolomide increased the overall survival of patients with glioblastoma multiforme (GBM; WHO grade IV), in particular when the O(6)-methylguanine DNA methyltransferase (MGMT) promoter is epigenetically silenced. Nevertheless, the prognosis remains poor, and relapse in GBM occurs regularly. This clinical behavior seems to be due to the existence of a therapy-resistant subpopulation of cells that induce tumor regrowth. The objective of this work was to analyze the role of aldehyde dehydrogenase (ALDH) 1A1 in mediating temozolomide resistance and its value as a predictor of clinical outcome in GBM patients. Nine GBM cell lines were treated with temozolomide alone or in combination with 4-diethylaminobenzaldehyde (DEAB), an inhibitor of ALDH1A1, or with ALDH1A1 short hairpin (sh)RNA. ALDH1A1 expression and MGMT status of 70 primary GBM patients were correlated with median survival. ALDH1A1 overexpression predicted temozolomide resistance in vitro. Sensitivity of ALDH1A1 positive/MGMT-positive cells to temozolomide could be restored by inhibition of ALDH1A1 by DEAB or by knockdown with shRNA, as indicated by increased cytotoxicity, reduced clonogenicity, and accumulation in the G2/M cell-cycle phase. The prognosis of patients with a high level of ALDH1A1 expression was poor compared with that of patients with low levels (P < .0001). ALDH1A1 is a new mediator for resistance of GBM to temozolomide and a reliable predictor of clinical outcome and may serve as a potential target to improve treatment of human GBM.

Involvement of inflammatory factors in pancreatic carcinogenesis and preventive effects of anti-inflammatory agents

Chronic inflammation is known to be a risk for many cancers, including pancreatic cancer. Heavy alcohol drinking and cigarette smoking are major causes of pancreatitis, and epidemiological studies have shown that smoking and chronic pancreatitis are risk factors for pancreatic cancer. Meanwhile, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) are elevated in pancreatitis and pancreatic cancer tissues in humans and in animal models. Selective inhibitors of iNOS and COX-2 suppress pancreatic cancer development in a chemical carcinogenesis model of hamsters treated with N-nitrosobis(2-oxopropyl)amine (BOP). In addition, hyperlipidemia, obesity, and type II diabetes are also suggested to be associated with chronic inflammation in the pancreas and involved in pancreatic cancer development. We have shown that a high-fat diet increased pancreatic cancer development in BOP-treated hamsters, along with aggravation of hyperlipidemia, severe fatty infiltration, and increased expression of adipokines and inflammatory factors in the pancreas. Of note, fatty pancreas has been observed in obese and/or diabetic cases in humans. Preventive effects of anti-hyperlipidemic/anti-diabetic agents on pancreatic cancer have also been shown in humans and animals. Taking this evidence into consideration, modulation of inflammatory factors by anti-inflammatory agents will provide useful data for prevention of pancreatic cancer.

Nuclear factor erythroid 2-related factor-2 activity controls 4-hydroxynonenal metabolism and activity in prostate cancer cells

4-Hydroxynonenal (HNE) is an end product of lipoperoxidation with antiproliferative and proapoptotic properties in various tumors. Here we report a greater sensitivity to HNE in PC3 and LNCaP cells compared to DU145 cells. In contrast to PC3 and LNCaP cells, HNE-treated DU145 cells showed a smaller reduction in growth and did not undergo apoptosis. In DU145 cells, HNE did not induce ROS production and DNA damage and generated a lower amount of HNE-protein adducts. DU145 cells had a greater GSH and GST A4 content and GSH/GST-mediated HNE detoxification. Nuclear factor erythroid 2-related factor-2 (Nrf2) is a regulator of the antioxidant response. Nrf2 protein content and nuclear accumulation were higher in DU145 cells compared to PC3 and LNCaP cells, whereas the expression of KEAP1, the main negative regulator of Nrf2 activity, was lower. Inhibition of Nrf2 expression with specific siRNA resulted in a reduction in GST A4 expression and GS-HNE formation, indicating that Nrf2 controls HNE metabolism. In addition, Nrf2 knockdown sensitized DU145 cells to HNE-mediated antiproliferative and proapoptotic activity. In conclusion, we demonstrated that increased Nrf2 activity resulted in a reduction in HNE sensitivity in prostate cancer cells, suggesting a potential mechanism of resistance to pro-oxidant therapy.