Cladosporols and PPARγ: Same Gun, Same Bullet, More Targets.

Several natural compounds have been found to act as PPARγ agonists, thus regulating numerous biological processes, including the metabolism of carbohydrates and lipids, cell proliferation and differentiation, angiogenesis, and inflammation. Recently, Cladosporols, secondary metabolites purified from the fungus Cladosporium tenuissimum, have been demonstrated to display an efficient ability to control cell proliferation in human colorectal and prostate cancer cells through a PPARγ-mediated modulation of gene expression. In addition, Cladosporols exhibited a strong anti-adipogenetic activity in 3T3-L1 murine preadipocytes, preventing their in vitro differentiation into mature adipocytes. These data interestingly point out that the interaction between Cladosporols and PPARγ, in the milieu of different cells or tissues, might generate a wide range of beneficial effects for the entire organism affected by diabetes, obesity, inflammation, and cancer. This review explores the molecular mechanisms by which the Cladosporol/PPARγ complex may simultaneously interfere with a dysregulated lipid metabolism and cancer promotion and progression, highlighting the potential therapeutic benefits of Cladosporols for human health.

Proliferation and migration of PC-3 prostate cancer cells is counteracted by PPARγ-cladosporol binding-mediated apoptosis and a decreased lipid biosynthesis and accumulation.

OBJECTIVES: Chemoprevention, consisting of the administration of natural and/or synthetic compounds, appears to be an alternative way to common therapeutical approaches to preventing the occurrence of various cancers. Cladosporols, secondary metabolites from Cladosporium tenuissimum, showed a powerful ability in controlling human colon cancer cell proliferation through a peroxisome proliferator-activated receptor gamma (PPARγ)-mediated modulation of gene expression. Hence, we carried out experiments to verify the anticancer properties of cladosporols in human prostate cancer cells. Prostate cancer represents one of the most widespread tumors in which several risk factors play a role in determining its high mortality rate in men. MATERIALS AND METHODS: We assessed, by viability assays, PPARγ silencing and overexpression experiments and western blotting analysis, the anticancer properties of cladosporols in cancer prostate cell lines. RESULTS: Cladosporols A and B selectively inhibited the proliferation of human prostate PNT-1A, LNCaP and PC-3 cells and their most impactful antiproliferative ability towards PC-3 prostate cancer cells, was mediated by PPARγ modulation. Moreover, the anticancer ability of cladosporols implied a sustained apoptosis. Finally, cladosporols negatively regulated the expression of enzymes involved in the biosynthesis of fatty acids and cholesterol, thus enforcing the relationship between prostate cancer development and lipid metabolism dysregulation. CONCLUSION: This is the first work, to our knowledge, in which the role of cladosporols A and B was disclosed in prostate cancer cells. Importantly, the present study highlighted the potential of cladosporols as new therapeutical tools, which, interfering with cell proliferation and lipid pathway dysregulation, may control prostate cancer initiation and progression.

Clinical and Biological Predictors of Cancer Incidence and Mortality in Patients with Stable Coronary Artery Disease.

Clinical and epidemiological evidence has recently revealed a link between coronary artery disease (CAD) and cancer. Shared risk factors and common biological pathways are probably involved in both pathological conditions. The aim of this paper was to evaluate whether and which conventional risk factors and novel circulating biomarkers could predict cancer incidence and death in patients with CAD. The study included 750 CAD patients, who underwent blood sampling for the evaluation of systemic inflammatory indexes (NLR and SII) and specific biomarkers of oxidative damage (leukocyte telomere length (LTL), mitochondrial DNA copy number (mtDNAcn)). Study participants were followed up for a mean of 5.4 ± 1.2 years. Sixty-seven patients (8.9%) developed cancer during the follow-up time, and nineteen (2.5%) died of cancer. Cox multivariable analysis revealed that age (HR = 1.071; 95% CI: 1.034-1.109; p < 0.001), smoking habit (HR = 1.994; 95% CI: 1.140-3.488; p = 0.016), obesity (HR = 1.708; 95% CI: 1.022-2.854; p = 0.041) and SII (HR = 1.002; 95% CI: 1.001-1.003; p = 0.045) were associated with cancer incidence, while only age (HR = 1.132; 95% CI: 1.052-1.219; p = 0.001) was a predictor of cancer death. Patients with lung and gastrointestinal cancers had significantly higher median mtDNAcn levels than those without cancer. Our study suggests that aggressive risk factor modification and suppression of chronic inflammation may be essential to preventing cancer in CAD patients.

Proinflammatory and Cancer-Promoting Pathobiont Fusobacterium nucleatum Directly Targets Colorectal Cancer Stem Cells.

Intestinal bacterial communities participate in gut homeostasis and are recognized as crucial in bowel inflammation and colorectal cancer (CRC). Fusobacterium nucleatum (Fn), a pathobiont of the oral microflora, has recently emerged as a CRC-associated microbe linked to disease progression, metastasis, and a poor clinical outcome; however, the primary cellular and/or microenvironmental targets of this agent remain elusive. We report here that Fn directly targets putative colorectal cancer stem cells (CR-CSCs), a tumor cell subset endowed with cancer re-initiating capacity after surgery and chemotherapy. A patient-derived CSC line, highly enriched (70%) for the stem marker CD133, was expanded as tumor spheroids, dissociated, and exposed in vitro to varying amounts (range 100-500 MOI) of Fn. We found that Fn stably adheres to CSCs, likely by multiple interactions involving the tumor-associated Gal-GalNac disaccharide and the Fn-docking protein CEA-family cell adhesion molecule 1 (CEACAM-1), robustly expressed on CSCs. Importantly, Fn elicited innate immune responses in CSCs and triggered a growth factor-like, protein tyrosine phosphorylation cascade largely dependent on CEACAM-1 and culminating in the activation of p42/44 MAP kinase. Thus, the direct stimulation of CSCs by Fn may contribute to microbiota-driven colorectal carcinogenesis and represent a target for innovative therapies.

Increased circulating cell-free DNA levels and mtDNA fragments in interventional cardiologists occupationally exposed to low levels of ionizing radiation.

Circulating cell-free DNA (ccf-DNA) and mtDNA (ccf-mtDNA) have often been used as indicators of cell death and tissue damage in acute and chronic disorders, but little is known about changes in ccf-DNA and ccf-mtDNA concentrations following radiation exposure. The aim of the study was to investigate the impact of chronic low-dose radiation exposure on serum ccf-DNA levels and ccf-mtDNA fragments (mtDNA-79 and mtDNA-230) of interventional cardiologists working in high-volume cardiac catheterization laboratory to assess their possible role as useful radiation biomarkers. We enrolled 50 interventional cardiologists (26 males; age = 48.4 ± 10 years) and 50 age- and gender-matched unexposed controls (27 males; age = 47.6 ± 8.3 years). Quant-iT™ dsDNA High-Sensitivity assay was used to measure circulating ccf-DNA isolated from serum samples. Quantitative analysis of mtDNA fragments was performed by real-time PCR. No significant relationships were found between ccf-DNA and ccf-mtDNA, and age, gender, smoking, or other clinical parameters. Ccf-DNA levels (44.2 ± 31.1 vs. 30.6 ± 19.2 ng/ml, P = 0.013), ccf-mtDNA-79 (2.6 ± 2.1 vs. 1.1 ± 0.8, P < 0.01), and ccf-mtDNA-230 copies (2.0 ± 1.8 vs. 1.04 ± 0.9, P = 0.02) were significantly higher in interventional cardiologists compared with the non-exposed group. In a subset (n = 15) of interventional cardiologists with a reliable reconstruction of cumulative professional exposure (59.7 ± 48.4 mSv; range: 1.4-182 mS), ccf-DNA (53.2 ± 41.3 vs. 36.4 ± 22.9 and 32.2 ± 20.5, P = 0.08), mtDNA-79 (2.4 ± 2.1 vs. 2.03 ± 1.7 and 1.09 ± 0.82, P = 0.05), and mtDNA-230 (2.0 ± 2.2 vs. 1.5 ± 1.4 and 1.04 ± 0.9, P = 0.09) tended to be significantly increased in high-exposure subjects compared with both low-exposure interventional cardiologists and controls. Our results provide evidence for a possible role of circulating DNA as a relevant biomarker of cellular damage induced by exposure to chronic low-dose radiation.

Genetic risk score and acute skin toxicity after breast radiation therapy.

Genetic predisposition has been shown to affect the severity of skin complications in breast cancer patients after radiotherapy. Limited data exist regarding the use of a genetic risk score (GRS) for predicting risk of tissue radiosensitivity. We evaluated the impact of different single-nucleotide polymorphisms (SNPs) in genes related to DNA repair mechanisms and oxidative stress response combined in a GRS on acute adverse effects induced by breast radiation therapy (RT). Skin toxicity was scored according to the Radiation Therapy Oncology Group (RTOG) criteria in 59 breast cancer patients who received RT. After genotyping, a multilocus GRS was constructed by summing the number of risk alleles. The hazard ratio (HR) for GSTM1 was 2.4 (95% confidence intervals [CI]=1.1-5.3, p=0.04). The other polymorphisms were associated to an increased adverse radiosensitivity, although they did not reach statistical significance. GRS predicted roughly 40% risk for acute skin toxicity per risk allele (HR 1.37, 95% CI=1.1-1.76, p<0.01). Patients in the top tertile had a fivefold higher risk of skin reaction (HR 5.1, 95% CI=1.2-22.8, p=0.03). Our findings demonstrate that the joint effect of SNPs from oxidative stress and DNA damage repair genes may be a promising approach to identify patients with a high risk of skin reaction after breast RT.

[Liquid nitrogen biobank: a resource for biomedical research]. / Biobanca ad azoto liquido: una risorsa preziosa per la ricerca biomedica.

Biobanks are a critical resource for "omics" technologies in order to dissect molecular mechanism and gene-environmental interactions of common diseases, such as cancer, cardiovascular diseases, diabetes, and neurodegenerative diseases. Progress in basic biomedicine may contribute to advance personalised medicine in which treatments will no longer be "one size fits all", but instead "tailored" to the molecular and genetic profile of each patient. Currently, there are major efforts worldwide to professionalize biobanks in order to move ahead from a "do-it-yourself" tissue collection - as is most frequent at present - for providing high quality preservation and storage of biological samples with potentially greater scientific impact. In this paper, we describe our recent experience in the design and development of a high-security liquid nitrogen storage system (-196°C) as a key resource for biomedical research.

Determinants of oxidative stress related to gender: relevance of age and smoking habit.

BACKGROUND: Magnitude and major causes of oxidative stress may be different between sexes, although limitedly addressed in clinical studies with controversial results. The present study aimed to determine whether any gender-related difference exists concerning oxidative stress in a population of 332 subjects of both sexes, in a wide age range, with and without cigarette smoking habit. METHODS: The Oxidative-INDEX was calculated after evaluation of serum hydroperoxides (ROMs) and total antioxidant capacity (OXY) by means of commercial kits (d-ROMs and Oxy-adsorbent Tests, Diacron, Italy) subtracting the OXY standardized variable from the ROMs standardized variable. RESULTS: The Oxidative-INDEX resulted higher in women with respect to men (p<0.001), in smokers (p<0.01) than in non-smokers, and correlated with cigarette number (p<0.01), age (p<0.001), and post-menopausal status (p<0.001). The multivariate analysis identified age, high blood pressure, and smoking habit as factors independently associated with the Oxidative-INDEX in men, whereas cigarette smoking and age represented the independent risk factors for an elevated oxidative stress status in women. CONCLUSIONS: Gender-based differences in oxidative stress levels may provide a biochemical basis for the epidemiologic differences in the disease susceptibility between sexes, and suggest different strategies for risk assessment, diagnosis, and treatment specifically targeted to men and women.

Effects of menopause and tibolone on different cardiovascular biomarkers in healthy women.

BACKGROUND AND AIM: The effects of tibolone on cardiovascular risk is not yet fully understood today. We designed this study to assess the effect of the menopausal status and tibolone treatment (2.5 mg/day for 3 months) on different biomarkers of cardiovascular risk in healthy women. METHODS: Blood arterial pressure were measured, and blood samples collected for glucose, lipid profile (total cholesterol, high density lipoproteins, HDL, low density lipoproteins, and triglycerides), inflammatory (C-reactive protein, Interleukin-6, IL-6, tumor necrosis factor alpha, TNF alpha) and oxidative stress (hydroperoxides and antioxidant capacity) evaluation in 15 premenopausal (mean age: 30 +/- 4 years) and 15 postmenopausal (mean age: 52 +/- 3, mean time from menopause 1.4 +/- 0.4 years) women before and after tibolone treatment. RESULTS: The menopausal status is associated with increased systolic and diastolic pressure (p<0.05), higher IL-6 (p<0.05) and TNF alpha (p<0.01), and lower antioxidants (p<0.01). However, blood pressure (p<0.05), glucose (p<0.05), TNF alpha (p<0.05) and HDL (p<0.05) fell after tibolone, which did not significantly affect levels of the other biochemical parameters. CONCLUSIONS: As menopause is associated with increased blood pressure, inflammation and oxidative stress, tibolone restores blood pressure and has beneficial effect on inflammation and glycemia without worsening oxidative stress, although it also reduces HDL levels. Such modifications should be taken into account when tailoring menopausal therapies to specific requirements of each woman.

Age-related oxidative stress modulation by smoking habit and obesity.

OBJECTIVE: To evaluate whether obesity and smoking habit may accelerate the age-related increase of oxidative stress. METHODS: The Oxidative-INDEX, a score reflecting both oxidative and antioxidant counterparts, was estimated in 179 subjects (50 males, aged 16-79 years). RESULTS: Oxidative stress results were elevated in obese and smoker subjects. Adjusted logistic regression analysis indicated obesity and smoking as independent variables for elevated Oxidative-INDEX (odds ratio=4.8 and 3.1, respectively). Oxidative-INDEX steadily rises at a mean rate of 5.3% (0.017 AU) per year in the overall population, showing twice and three times higher annual rate increase in smokers and obese subjects. CONCLUSION: Our results suggest the pro-ageing effects of cigarette smoking and obesity by a more rapid and sharp elevation of the oxidative stress status.

An oxidative stress score as a combined measure of the pro-oxidant and anti-oxidant counterparts in patients with coronary artery disease.

UNLABELLED: Oxidative stress plays a key role in the pathogenesis and development of atherosclerosis. AIM: To evaluate the relationship between a novel oxidative stress index (reflecting both oxidative and anti-oxidant counterparts) with traditional cardiovascular risk factors and C-reactive protein (CRP) in coronary artery disease (CAD). METHODS: 100 angiographically proven CAD and 70 control subjects (mean age: 65+/-10 years, 110 males), underwent a global cardiovascular risk assessment and serum CRP and oxidative stress estimation. The Oxidative-INDEX was calculated after automated evaluation of serum hydroperoxides and total anti-oxidant capacity (D-ROM and OXY-adsorbent Test, Diacron, Italy) subtracting the OXY standardized variable from the ROM standardized variable. RESULTS: The Oxidative-INDEX was higher in CAD with respect to control subjects (p < 0.001). A stepwise elevation in the Oxidative-INDEX levels was found depending on the number of affected vessels (p < 0.001). Oxidative stress was elevated according to the presence of diabetes (p < 0.001), smoking habit (p < 0.01), and hypercholesterolemia (p < 0.05). Oxidative-INDEX significantly correlated with aging (p < or = 0.05) and CRP (p < 0.001). The Oxidative-INDEX increased with the number of cardiovascular risk factors (p < 0.001). After adjustment for traditional CV risk factors, the multivariate logistic regression analysis indicated the Oxidative-INDEX concentration as an independent factor for CAD (odds ratio=1.4, confidence intervals=1.1-1.9, p < 0.05). CONCLUSION: Oxidative stress represents a shared molecular pathway in atherosclerotic-related conditions, and its estimation by the automated Oxidative-INDEX could represent a valuable tool and a promising target in the prevention, diagnosis and treatment of CAD in the clinical setting.

Estrogen therapy effects on different vasoactive factors in recent postmenopausal healthy women.

BACKGROUND: To evaluate whether the route of estrogen therapy (ET) may affect the levels of different vasoactive factors in healthy recent post-menopausal women. METHODS: We conducted a cross-over study in 20 healthy nonsmoking women in recent postmenopause (1.8+/-0.1 years). Women received either 1-month oral-ET (O-ET, 2 mg oral micronized 17beta estradiol daily) or transdermal-ET regimen (T-ET, 17beta estradiol 1.5 mg gel daily) with a 1-month wash-out interval. Blood pressure, plasma levels of endothelin-1 (ET), 6-ketoPGF1a (6-ketoPG, prostacyclin metabolite), nitrite/nitrate (NOx), epinephrine (E) and norepinephrine (NE) and lipid profile were measured at baseline and after each treatment. RESULTS: Both regimens significantly reduced E (p<0.01) and NE levels (p<0.05). O-ET reduced low-density lipoproteins (LDL) levels (p<0.05) and increased NOx values (p<0.01). Neither regimen caused significant changes of ET or 6-ketoPG. CONCLUSIONS: Our results, obtained in healthy women in recent menopause, indicate that the ratio between vasodilator (NOx and prostacyclin) and vasoconstrictor (ET) bioavailability shifted towards the previous ones after O-ET, while it remained unchanged after T-ET; moreover, catecholamines levels were reduced by both treatments already from 1 month of therapy. These changes might represent very early beneficial effects evoked by ET on the cardiovascular system.