Red sludge-induced mRNA and miRNA expression alterations in vital organs of CBA/Ca mice.

Several studies have investigated the ecological and genotoxic effects of the red mud accident in 2010 in Ajka, Hungary, but none was designed to reveal the early biological effects of red mud exposure at the level of early-responding gene expression. To address relevant questions, in the present study expression alterations of oncogenes (c-myc, K-ras), tumor suppressor genes (Bcl2, p53) and apoptosis-regulatory micro(mi) RNAs (miR-21, miR-27a, miR-93, miR-221) were analized 1, 3, 6 and 24 h after a single intraperitoneal injection of red mud to CBA/Ca mice. We observed changes in the expression of all investigated mRNAs, miR-21 and miR-221 in the liver, spleen, lung, kidney and lymph nodes of mice. An overexpression of the investigated genes was observed, but the level and the peak of the alteration differed according to examined tissue.

The possible role of Mena protein and its splicing-derived variants in embryogenesis, carcinogenesis, and tumor invasion: a systematic review of the literature.

The Ena/VASP (enabled/vasodilator stimulated phosphoprotein) family includes the binding actin proteins such as mammalian Ena (Mena), VASP, and Ena-VASP-like. It is known that the perturbation of actin cycle could determine alteration in the mobility of cells and in consequence of organogenesis. Few recent studies have revealed that Mena protein could play a role in breast or pancreatic carcinogenesis. Based on our researches, we observed that the intensity of Mena expression increased from premalignant to malignant lesions in some organs such as large bowel, stomach, cervix, and salivary glands. These findings prove that Mena could be a marker of premalignant epithelial lesions. In premalignant lesions, it could be helpful to define more accurately the risk for malignant transformation. In malignant tumors, correlation of expression of its splice variants could indicate metastatic behavior. In conclusion, we consider that it is necessary to analyze the expression of Mena splice variants in a higher number of cases, in different epithelial lesions, and also in experimental studies to define its exact role in carcinogenesis and also its possible prognostic and predictive values.

The role of p66shc in taxol- and dichloroacetic acid-dependent renal toxicity.

BACKGROUND/AIM: Taxol and dichloroacetic acid (DCA) are anticancer agents with potential renal toxicity. Previously, we have shown that the Ser36-phosphorylated p66shc adaptor protein mediates renal toxicity of selected anticancer modalities through increasing production of intracellular reactive oxygen species and consequent mitochondrial depolarization. Here, we analyzed whether p66shc plays a role in potential renal toxicity of Taxol and DCA. MATERIALS AND METHODS: Cultured renal proximal tubule cells (TKPTS) were used. ROS production, mitochondrial depolarization (JC-1), cell injury [lactate dehydrogenase (LDH) release] and Ser36 phosphorylation of p66shc were determined after treatment with Taxol and DCA. Involvement of p66shc in adverse effects of these drugs was determined in p66shc knockdown, Ser36 phosphorylation (S36A) and cytochrome c-binding (W134F)- deficient cells. RESULTS: Both Taxol and DCA increased ROS production, mitochondrial depolarization, injury and Ser36 phosphorylation of p66shc in TKPTS cells. We showed that ROS production is responsible for mitochondrial depolarization and consequent injury. Knockdown of p66shc, mutation of its Ser36 (S36A) or cytochrome c binding site (W134F) attenuated adverse effects of the two drugs. CONCLUSION: Taxol and DCA are potentially nephrotoxic owing their adverse effects on activation of p66shc. Manipulation of expression or activity of p66shc may provide a means of ameliorating nephrotoxicity of these agents.

Evaluation of MicroRNA expression pattern of gastric adenocarcinoma associated with socioeconomic, environmental and lifestyle factors in northwestern Hungary.

AIM: Gastric cancer is among the most common causes of cancer-related death worldwide. Since microRNAs (miRNAs) represent an emerging field of cancer research, there is an increasing interest regarding the miRNA responses to environmental and lifestyle exposures. The aim of our study was to analyze whether social status, living conditions and lifestyle behaviours, such as cigarette smoking and alcohol consumption, are associated with specific miRNA expression patterns of gastric adenocarcinoma. MATERIALS AND METHODS: Thirty-nine formalin-fixed paraffin-embedded primary gastric adenocarcinoma and nine non-tumourous samples were analyzed by real-time polymerase chain reaction. The expression levels of miR-21, miR-34a, miR-93, miR-143, miR-203, miR-205, miR-223 were compared in gastric adenocarcinoma samples of patients with different demographical characteristics, social status, drinking and smoking habits. RESULTS: Overexpression of miR-21, miR-143 and underexpression of miR-34a were observed in gastric cancer samples relative to the controls. Elevated expression of miR-21 was detected in patients with low social status. Smokers showed higher expression of miR-21 and lower expression of miR-143. Up-regulation of miR-203, miR-205 and miR-223 was identified in patients with regular alcohol consumption. Patients living in an urban environment had elevated expression levels of miR-143 and miR-34a. DISCUSSION: Differential miRNA expression patterns of gastric adenocarcinoma of the same histopathology from a small geographic region's population show homogenous correlations with the existence of common risk factors.

Regulation of cytotoxic, non-estrogenic, oxidative stress-induced processes of zearalenone in the fission yeast Schizosaccharomyces pombe.

This study investigates the non-estrogenic mode of zearalenone (ZEA) toxicity in a novel aspect via accumulation of reactive oxygen species (ROS) and the regulation of the activities of antioxidant enzymes in the Schizosaccharomyces pombe in acute toxicity tests. In comparison with the control, 500 µM ZEA treatment caused 66% decrease in the concentration of glutathione (GSH), which was a consequence, in the absence of ZEA-GSH interaction, of the GSH-consuming processes of the antioxidant system; this depletion of GSH initiated a 1.8- and 2.0-fold accumulation of the superoxide anion and hydrogen peroxide, but did not increase the concentration of the hydroxyl radical; ROS-induced adaptation processes via activation of the Pap1 transcription factor resulted in significantly increased activities of superoxide dismutases, catalase, glutathione reductase and glutathione S-transferase, and decreased activities of glutathione peroxidase and glucose-6-phosphate dehydrogenase. This treatment altered the sterol composition of the cells by inducing decreased concentrations of ergosterol, squalene and 24-methylene-24,25-hydrolanosterol, and also elevated the number of fragmented nuclei. Cells strived to correct the unbalanced redox state by regulation of the antioxidant system, but this was not enough to defend the cells from the disturbed sterol composition, the cell cycle arrest, and the fragmentation of nuclei.

Alternatives for the intensive follow-up after curative resection of colorectal cancer. Potential novel biomarkers for the recommendations.

Early diagnosis of recurrence and metastasis of colorectal cancer following surgery of curative intent is of vital importance in terms of survival and quality of life. The consistent implementation of appropriate patient follow-up strategy is therefore essential. Debates over the methodology, evaluation and strategy of follow-up have been known for many years, and continue today. By introducing several follow-up models, the present paper offers different options featuring certain individual, national and international, conceptual and financial aspects. Colorectal cancer is an important public health concern due to its destructive nature and frequency, it is therefore essential to develop new monitoring strategies, involving new biomarkers and extensive clinical validation. Since the recurrence rate is very high in high-risk patients, the improvement of individual patient risk estimates and the utilization of a corresponding follow-up model require broad international co-operation and common practice, along with the determination of optimal levels of evidence.

Unique microRNA expression profiles in cervical cancer.

Cervical cancer is the second leading cause of death among female patients with cancer in the world. Our aim was to analyze cervical cancer cases, in the Southwestern Transdanubian Region of Hungary, with regard to human papillomavirus (HPV) genotype and histological and clinical grading. After HPV testing and genotyping, the expressions of eight different pre-microRNAs (miR-21, miR-27a, miR-34a, miR-146a, miR-155, miR-196a, miR-203, miR-221) in formalin-fixed paraffin-embedded (FFPE) primary human cervical cancer samples were evaluated with the help of the LightCycler 480 PCR System (Roche). Statistically significant overexpression of miR-21 (p=0.004), miR-27a (p=0.018), miR-34a (p<0.001), miR-155 (p=0.021), miR-196a (p=0.032), miR-203 (p=0.037) and miR-221 (p=0.017) were observed in squamous cell carcinoma, regardless of HPV status and clinical grading. Significant overexpression of miR-21 (p=0.004), miR-27a (p=0.02), miR-34a (p<0.001), miR-196a (p=0.027) and miR-221 (p=0.031) was characteristic of HPV-positive squamous cell carcinomas in contrast to adenocarcinomas of the same HPV status.

miRNA expression profiles of oral squamous cell carcinomas.

BACKGROUND: Oral squamous cell carcinoma (OSCC) development involves complex machinery of genomic and epigenetic regulations including microRNA (miRNA) expression changes. We aimed to analyze the expression patterns of a set of miRNAs in human TNM stage I and II OSCC samples in an autologous normal mucosa-controlled experimental design. MATERIALS AND METHODS: Forty samples of OSCC and 40 matched normal tissues were evaluated for miR-21, miR-155, miR-191, miR-146a, miR-221 and miR-222 expression in a LightCycler 480(PCR) system. RESULTS: Our results showed significant overexpression of miR-21, miR-155, miR-191 and miR-221 in paired-sample t-test and the sensitivity/specificity of tests were over 90% in the case of miR-21 and miR-155 on the receiver operating characteristic curve (ROC) analysis. CONCLUSION: Our results underline the role of miR-21 in OSCC and support the possible causal role of miR-155 and miR-221 in oral carcinogenesis. The overexpression of miR-191 is a novel finding in squamous cell carcinoma.

Expression of NFkB1, GADD45A and JNK1 in salivary gland carcinomas of different histotypes.

The class of salivary gland tumours is very heterogenous, both in a histopathological and clinical sense. Since they are uncommon lesions, their clinical management is still problematic. Molecular mechanisms underlying the development of these cancer types may be fundamental for the diagnosis, treatment and prognosis of this disease. In this study, the gene expression of nuclear factor-kappa B (NKkB1/p65), c-Jun N-terminal kinase (JNK1) and growth arrest and DNA damage (GADD45A), which all play an important role in inflammatory and cell survival mechanisms, was assessed in benign and malignant neoplasms of the salivary gland. The absolute mRNA content of paraffin embedded samples of salivary gland cancer was determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) using specific primers for NFkB1, GADD45A and JNK1. Expression values (relative to HPRT) were statistically evaluated. Among the detected alterations in gene expression, the only difference reaching statistical significance was in the case of NFkB1 in adenocystic carcinomas (p=0.05). Given the importance of these signalling mechanisms in the biology of tumorigenesis, these results may be implemented in further research and these genes might become targets for innovative diagnostic and therapeutic strategies.

Deuterium depleted water effects on survival of lung cancer patients and expression of Kras, Bcl2, and Myc genes in mouse lung.

Although advances in cancer therapies continue to develop, the shortness of the survival of lung cancer patients is still disappointing. Therefore, finding new adjuvant strategies is within the focus of cancer cure. Based on observations that deuterium depletion inhibits the growth of cancer cell lines and suppresses certain proto-oncogenes, we have conducted a clinical study in 129 patients with small cell and nonsmall cell lung cancers who consumed deuterium-depleted drinking water (DDW) as a nontoxic agent in addition to conventional chemotherapy and radiotherapy. Median survival time (MST) was 25.9 mo in males and 74.1 mo in female patients; the difference between genders was statistically significant (p < 0.05). Median survival of subjects with brain metastasis was 27.1 mo. Cumulative 5-yr survival probabilities were 19%, 52%, and 33% in males, females, and all patients with brain metastasis, respectively. Gene expression analysis in mouse lung indicated that DDW attenuates 7,12-dimethylbenz(a)anthracene (DMBA)-induced expression of Bcl2, Kras, and Myc in females. In conclusion, DDW counteracts the DMBA-induced overexpression of Bcl2, Kras and Myc genes in mouse lung, and it may extend survival of lung cancer patients as a nontoxic anticancer dietary supplement, especially for women with tumors overexpressing cancer-related genes, because MST of DDW-consuming group was 2-4 times longer than it is generally observed in lung cancer patients.

Association of pre-miR-146a rs2910164 polymorphism with the risk of head and neck cancer.

BACKGROUND: Over- or underexpression of miR-146a has been reported in several different human tumor types, and a polymorphism in its precursor form (pre-miR-146a rs2910164 G/C) has been recently studied in connection with cancer susceptibility. The aim of the present study was to investigate the possible influence of the pre-miR-146a rs2910164 polymorphism on the risk of squamous cell carcinoma of the head and neck (HNSCC). PATIENTS AND METHODS: The study included 468 patients with HNSCC and 468 cancer-free, age-, gender-, and smoking-matched controls. The miR-146a genotypes were determined using polymerase chain reaction with confronting two-pair primers, and their distribution was compared by multivariate binary logistic regression analysis. RESULTS: Occurrence of heterozygous (odds ratio, OR=1.46, 95% confidence interval, CI=1.10-1.95, p=0.009) and C/C homozygous (OR=2.37, 95% CI=1.01-5.60, p=0.048) individuals was significantly more frequent among patients with HNSCC than in the control group. CONCLUSION: The pre-miR/146a C allele may contribute to an increased susceptibility to HNSCC.

Effects of purified glycerol from biodiesel on miRNAs compared to the expression profile of selected mRNAs in Balb/c mice.

BACKGROUND: We investigated the effect of corn-derived biodiesel glycerol on microRNAs (miRNAs) and mRNAs, which play a central role in regulating cell survival, apoptosis and carcinogenesis. MATERIALS AND METHODS: Inbred Balb/c mice were treated with purified glycerol from biodiesel for 24 hours. After administration, we determined the expressions of miR-21, miR-27a, miR-34a, miR-93, miR-143, miR-146a, miR-148a, miR-155, miR-196a, miR-203, miR-205, miR-221 and nuclear factor kappa-light-chain enhancer of activated B-cells-1 (Nfκb1), mitogen-activated protein kinase-8 (Mapk8) and v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (K-ras) genes in the liver of mice. RESULTS: We found a parallel altered expression of miRNAs and mRNAs in animals consuming biodiesel glycerol that compared to control mice; these alterations reached significant levels only in few cases. CONCLUSION: Biodiesel glycerol presents no higher risk for carcinogenicity or toxicity.

Very early effect of DMBA and MNU on microRNA expression.

BACKGROUND: microRNA expression profile analysis provides evaluation of the early stages of carcinogenesis. This study focuses on early alteration of miRNA expression after treatment with different carcinogens. MATERIALS AND METHODS: Mice were intraperitoneally injected with one dose of 7,12-dimethylbenz(α)anthracene (DMBA) and N-methyl-N-nitrosourea (MNU). The expression of miRNAs were analyzed 3 and 6 hours after the treatment, using quantitative real-time-polymerase chain reaction. RESULTS: Underexpression of miR-34a and miR-155 were detected in the liver, spleen and kidneys at 3 and 6 hours after MNU treatment. In the lungs and kidneys, the expression of miR-21 was significantly elevated 6 hours after DMBA treatment, while in the liver, MNU induced higher expression levels of miR-21 at 3 and 6 hours compared to treatment with DMBA. CONCLUSION: The different response of miRNAs to carcinogens emphasizes their possible role as potential epidemiological biomarkers in early phases of environmental tumorigenesis.

Cisplatin enhances interaction between p66Shc and HSP27: its role in reorganization of the actin cytoskeleton in renal proximal tubule cells.

BACKGROUND/AIM: Cisplatin nephrotoxicity includes early activation of the pro-apoptotic p66Shc and disorganization of the actin cytoskeleton, integrity which is regulated by heat-shock protein-27 (Hsp27). Here we determined the potential role of p66Shc in abrogating the Hsp27 function. MATERIALS AND METHODS: Effects of p66Shc knockdown and Hsp27 overexpression on F-actin stress fibers after cisplatin treatment were visualized by phalloidin staining. Binding of p66Shc to Hsp27 after cisplatin treatment was determined by immunoprecipitation in cell and tissue lysates. The role of p66Shc and its Ser36 phosphorylation in Hsp27 binding was assessed by overexpressing it or mutating its Ser36 residue. RESULTS: Knockdown of p66Shc and overexpression of Hsp27 ameliorated cisplatin-mediated collapse of the actin cytoskeleton. Further studies revealed that p66Shc binds Hsp27 after treatment with cisplatin that requires Ser36 phosphorylation of p66Shc. CONCLUSION: We propose a novel function of p66Shc that, through interacting with Hsp27, accelerates cisplatin-dependent disruption of the actin cytoskeleton.

Effect of an educational intervention on Hungarian adolescents' awareness, beliefs and attitudes on the prevention of cervical cancer.

The alarming national data on the mortality and morbidity rates of cervical cancer as well as the results of a Hungarian survey demonstrating adolescents' low level of understanding of human papillomavirus (HPV) infection and HPV vaccination encouraged the authors to conduct an educational intervention. The aim of this survey was to explore the impact of a brief, HPV-focused program on adolescents' knowledge, beliefs and attitudes. A self-administered anonymous questionnaire was completed by 394 male and female adolescents in September, 2010, in Hungary. Half of the students (48.5%) then had a one-off educational intervention on aspects cervical cancer lasting 45 min lesson, while the rest of the participants, the control group, did not have the educational intervention. Three months following the education, both groups were retested using the same questionnaire. Data were analysed using Statistical Package for the Social Sciences (SPSS). Following the education, significant increase was detected in cervical cancer awareness: causal relationship between HPV and cervical cancer (7.9% → 22.1%, p<0.05), or perception of HPV vaccination (61.3% → 85.9%, p<0.05). Similarly, health-related beliefs have enhanced, such as 'HPV may cause cervical cancer' (64.9% → 81.0%, p<0.05) or 'cervical cancer may be prevented by vaccination' (66.5% → 85.3%, p<0.05). Our data also highlighted that Hungarian adolescents have been practising extremely risky sexual behaviour. Nearly half of the sexually active adolescents had engaged in 'one-night relationship' (41.1%) as well as having sexual intercourse without any contraceptive safety measures (44.3%). In addition to providing adolescents with clear and meaningful information about the implications of a HPV infection and addressing their fears of screening and vaccination, health education should focus on promoting safe sex behaviour by promoting the use of condoms and reducing the number of sexual partners to limit the spread of HPV, and also on encouraging the participation in regular cervical screenings, thus reducing the incidence of cervical cancer.

[Need for developing a new strategy in the follow-up of colorectal cancer patients; the micro RNAs (miRNAs), as potential new biomarkers of early detection]. / Új követési stratégia kidolgozásának szükségessége a vastag- és végbélrákos betegek követésére; a mikroRNS-ek (miRNS) mint a korai felismerés lehetséges új biomarkerei.

In the mortality statistics of European countries colorectal cancers are known to assume the 2nd place after lung cancer. The mortality indices are particularly unfavourable in Hungary. Early detection is therefore of vital importance to the patient either the detection of the primary or recurrence after successful surgery is concerned. The latter is only feasible within a proper follow-up strategy. The present review focuses on follow-up due after surgical removal of the tumour with special emphasis on the efficacy of a new biomarker group (miRNAs) and their potential combination with the traditional markers. It is a model in the follow-up strategy that considers the results of risk assessment, as well. Since the methodology and strategy of follow-up are still controversial matters it is obvious that the development of a new follow-up strategy is imperative.

DMBA induces deregulation of miRNA expression of let-7, miR-21 and miR-146a in CBA/CA mice.

BACKGROUND: 7,12-Dimethylbenz(α)anthracene (DMBA) is a carcinogen capable of inducing various types of tumors. MATERIALS AND METHODS: We investigated the effect of DMBA on micro-RNA expression in CBA/CA H2(k) inbred mice after 24 hours and one week from exposure. RESULTS: Expression levels of miR-21, miR-146a and let-7a were significantly higher in the vital organs of the mice 24 hours after DMBA exposure compared to those of the controls. On the other hand, a significant down-regulation of the miRNAs was observed seven days after DMBA administration. CONCLUSION: Based on our data, DMBA has an impact on the expression of miR-21, let-7a and miR-146a genes. The altered micro-RNA expression can be regarded as an early effect of exposure to chemical carcinogens. To our knowledge, this is the first study of miRNA modulation caused by DMBA in non-malignant tissues.

Effects of cytochrome P450 1A1 and uridine-diphosphate-glucuronosyltransferase 1A1 allelic polymorphisms on the risk of development and the prognosis of head and neck cancers.

We studied the effect of allelic polymorphisms of cytochrome P450 1A1 (CYP1A1) and uridine-diphosphate-glucuronosyltransferase 1A1 (UGT1A1) on the risk of development of head and neck cancers and overall survival. One hundred and forty-two head and neck cancer patients (48 with laryngeal, 42 with hypopharyngeal and 52 with mesopharyngeal tumours) were included in the study. The control group (150 individuals) included volunteers without malignant tumours. There was no statistically significant difference in age, sex distribution, or smoking habits between the two groups. The participants were genotyped for the CYP1A1 isoleucine/valine (Ile/Val) polymorphism in exon 7 and for the UGT1A1 thymine-adenine-repeat polymorphism (*1 and *28 alleles) in the promoter region of the gene. The effect of the allelic variants on survival was studied using the log-rank test, whereas the χ-test and odds ratios (OR) with 95% confidence intervals (CI) were used to compare the allelic frequencies between patients and controls. Our study revealed a significant link between the occurrence of the CYP1A1 Ile/Val, Val/Val (OR: 1.72, 95% CI: 1.02-2.96, P=0.044) and UGT1A1*28 alleles (OR: 2.74, 95% CI: 1.45-5.18, P=0.002) and an increased risk of head and neck cancers. These alleles decreased the duration of survival significantly (P=0.018 and 0.006). The survival was significantly more strongly reduced when the two high-risk alleles were carried simultaneously (OR: 2.149, 95% CI: 1.111-4.157, P=0.001). Our results suggest that the use of the CYP1A1 Ile/Val and Val/Val variants and UGT1A1*28 as biomarkers can aid risk assessment while their prognostic value can aid planning of individual therapy.

Historical public health in central europe with special reference to hungary. Long-term environmental effects of a historical cataclysm.

ABSTRACT: Hungary, in the centre of Carpathian basin grapples with numerous challenges in order to improve catastrophic indices of environmental conditions of the country, as well as the state of health of the population. Some of these problems are subjects of financial and health policy, and can be solved internally. The remaining environmental problems can only be remedied by cooperation with neighbouring younger countries. This vitally important cooperation is hampered by severe historical conflicts burdening even the present political affiliations. The authors give a short introduction and explanation of the recent sensitive situation in this central European region, as a late consequence of an historical cataclysm happened more than nine decades ago.

Epigenetic modifiers exert renal toxicity through induction of p66shc.

BACKGROUND/AIMS: Trichostatin A (TSA) and 5-azacytidine (5AZA) induce reactive oxygen species (ROS)-mediated injury in renal proximal tubule cells. Since TSA and 5AZA are activators of p66shc, we questioned whether p66shc may mediate renal toxicity of TSA- and 5AZA. MATERIALS AND METHODS: Renal proximal tubule cells were treated with either TSA or 5AZA for 24 hours followed by treatment with 200 µM H(2)O(2). Expression of p66shc and activity of its promoter, as well as its mitochondrial and cytochrome c binding were determined. Impact of knockdown of p66shc and mutation of its cytochrome c-binding site on ROS production and cell injury was studied. RESULTS: TSA, and 5AZA increased expression of p66shc through induction of its promoter and also increased its mitochondrial/cytochrome c binding. Knockdown or mutation of the cytochrome c binding site of p66shc attenuated ROS production and cell injury. CONCLUSION: Therapeutic means that interfere with induction of p66shc may ameliorate renal toxicity of those epigenetic modifiers.