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.

[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.

The effect of fenugreek on the gene expression of arachidonic acid metabolizing enzymes.

The main bioactive compounds of Trigonella foenum graecum L. (fenugreek) seeds are protodioscin, trigoneoside, diosgenin and yamogenin, which have anticarcinogenic potency through inhibition of cell proliferation and inhibition of prostaglandin synthesis. The effect of fenugreek on ALOX and COX genes was examined in AKR/J H-2(k) mice exposed to dimethylbenz[α]anthracene (DMBA), a potent carcinogen. The expression pattern of these genes was determined by detecting the mRNA expression in various tissues (the lungs, liver, spleen and the kidneys) in four groups of mice. Two groups were fed with normal and two of them with fenugreek containing nutriment. Each group divided into DMBA treated and control groups. Mice were autopsied on day 7 after DMBA treatment for mRNA isolation. Fenugreek consumption itself did not change gene expression compared with the control group. DMBA could increase the expression of ALOX12, ALOX15, ALOX5 genes mainly in all organs. Fenugreek consumption was generally protective in each organ in a different manner. DMBA treatment increased COX2 gene expression, but fenugreek was protective in all tissues examined. In COX1 gene, the fenugreek diet could suppress the expression, except for spleen, independently from carcinogen exposure. Therefore by inhibiting the arachidonic acid metabolism fenugreek may prevent tumorigenesis.

Mixtures of Uncaria and Tabebuia extracts are potentially chemopreventive in CBA/Ca mice: a long-term experiment.

A long-term experimental animal model was developed by our research group for the evaluation of potential chemopreventive effects. The inhibitory effects of agents on carcinogen (7,12-dimethylbenz[a]anthracene (DMBA) induced molecular epidemiological biomarkers, in this case the expression of key onco/suppressor genes were investigated. The expression pattern of c-myc, Ha-ras, Bcl-2, K-ras protooncogene and p53 tumour suppressor gene were studied to elucidate early carcinogenic and potential chemopreventive effects. The consumption of so-called Claw of Dragon tea (CoD™ tea) containing the bark of Uncaria guianensis, Cat's Claw (Uncaria sp. U. tomentosa) and Palmer trumpet-tree (Tabebuia sp. T. avellanedae) was able to decrease the DMBA-induced onco/suppressor gene overexpression in a short-term animal experiment. In a following study CBA/Ca mice were treated with 20 mg/kg bw DMBA intraperitoneally (i.p.) and the expression patterns of onco/suppressor genes were examined at several time intervals. According to the examined gene expression patterns in this long-term experiment the chemopreventive effect of CoD™ tea consumption could be confirmed.

Changes in expression of oncogenes and TP53 tumour suppressor gene as biomarkers in head and neck cancers.

Despite modern diagnostic procedures and up-to-date therapy, the survival of head and neck tumour patients is unfavourable. This can be explained by several factors, one of which is the late recognition of the tumour. This study related to the changes in expression of the c-myc and Ha-ras oncogenes and the p53 tumour suppressor gene as biomarkers in head and neck cancer cases. The gene expressions were investigated on RNA gained from peripheral white blood cells of head and neck cancers patients before and after definitive treatment. The results were compared with those on a control group of patients with non-tumorous diseases. The gene expressions were significantly higher in the cancer group than that in the control group (volunteer medical staff and medical students). After definitive treatment, the expressions of all these genes were decreased in patients in whom there was no recurrence of the tumour, but enhanced in the event of recurrence. Such measurement may serve as reliable biomarkers to monitor tumour development and the efficiency of therapy. The method may also be useful for the early identification of populations exposed to noxe, which may lead to the development of head and neck cancers.

[Impact of microRNAs on molecular epidemiology]. / Mikro-RNS-ek jelentosége a molekuláris epidemiológiában.

Cancer research concerning short non-coding RNA sequences and functionally linked to RNA interference (RNAi) have reached explosive breakthrough in the past decade. Molecular technology applies microRNA in extremely wide spectrum from molecular tumor prediction, diagnostics, progression monitoring and prevention. Functional analysis of tissue miRNA and cell-free serum miRNA in posttranscription and translation regulation innovated and restructured the knowledge on the field. This review focuses on molecular epidemiology and primary prevention aspects of the small non-coding RNA sequences.

Skin cancer risk factors among primary school children: investigations in Western Hungary.

OBJECTIVE: To evaluate the factors associated with sunburns and with sun protection practice in Hungarian primary school children. METHOD: We investigated children's (the median age: 8, range 5 to 12 years) and parents' assessment of sun sensitivity and sun protection characteristics in cities Gyor and Zalaegerszeg (Hungary) in 2004. This cross-sectional study was part of a programme intended to increase children's and parents' awareness of harmful effects of excessive sunbathing. Analyses were based on 1804 multiple choice questionnaires. RESULTS: At multivariate analysis a significant association between sunburns and fairness of complexion, freckles, use of sunscreens and T-shirts, and higher school-class level was observed. Sunburn was inversely associated with hat-wearing. Parents were more likely to apply sunscreen to children with light eyes and to the younger ones, to protect fair skinned children with T-shirts; to protect males and children with fair skin and light eyes with hats. CONCLUSION: Since environmental factors play an important role in the development of skin cancer, morbidity could be reduced by primary prevention. Sun protection habits should therefore be taught early in life, and parents' behaviour adapted. Phenotype is not only related to sunburns but it also appears to influence parents' sun safety behaviour.

Feeding purified glycerol from biodiesel to CBA/CA mice: effects on Gadd45a and Nfkappab1 expressions.

BACKGROUND: The turn towards renewable energy sources has increased the production of biodiesel from rapeseed oil, leaving glycerol as a valuable by-product. Several studies have evaluated this product in feed for poultry, swine and ruminants. We investigated the effect of these glycerol products on the expression of DNA damage-inducible genes in mice. MATERIALS AND METHODS: CBA/CA mice were administered two different purified glycerol products (SZME2, SZME3) for 3, 6 and 24 hours. After dietary exposure, gene expressions of nuclear factor kappa-light-chain-enhancer of activated B-cells 1 (NFkb1) and growth arrest and DNA-damage-inducible protein 45 alpha (Gadd45a) were analysed. RESULTS: SZME2 induced a down-regulation of the two genes in all investigated organs, including the bone marrow in both genders. After administration of SZME3, up-regulation of the two genes was observed in bone marrow in males, and the up-regulation of Gadd45a in liver, also in males. CONCLUSION: Based upon our data, SZME3, which contains glycerol of higher purification, did not induce down-regulation in genes which are involved in apoptosis.

Epigenetic modifiers exacerbate oxidative stress in renal proximal tubule cells.

BACKGROUND: Increased production of reactive oxygen species (ROS) by anticancer drugs has been described in patients with various malignancies, which might attribute to their nephrotoxicity. MATERIALS AND METHODS: The effects of two epigenetic modifiers - trichostatin A (TSA) and 5-aza-deoxycytidine (5AZA) - on ROS production and cell injury alone or in combination with mild oxidative stress were studied in mouse renal proximal tubule cells. RESULTS: Both agents increased mitochondrial ROS production and consequent lactate dehydrogenase (LDH) release either alone or in combination with a low dose of H(2)O(2). The antioxidant N-acetyl-cysteine (NAC) abolished LDH release. It was also found that CREB-mediated transcription, vital for survival of proximal tubule cells, is attenuated by these anticancer agents. CONCLUSION: The ROS-inducing activity of TSAI and 5AZA might explain the in vivo nephrotoxicity of epigenetic modifiers. The mechanisms that are responsible for this injury could involve attenuation of pro-survival signaling and/or activation of death signaling pathway(s) associated with mitochondrial ROS release.

The plant-derived natural compound Flavin 7 attenuates oxidative stress in cultured renal proximal tubule cells.

BACKGROUND: Cancer therapies and cancer progression can increase oxidative stress that might account for renal toxicity in cancer patients. Flavin 7 (F7) is a natural polyphenol-containing dietary supplement with potential antioxidant activity. Therefore, it might help to attenuate renal toxicity of chemotherapeutics. MATERIALS AND METHODS: Cultured mouse renal proximal tubule cells were subjected to H(2)O(2)-mediated oxidative stress. Potential antioxidant effects of F7 were assessed by measuring the production of reactive oxygen species (ROS), mitochondrial depolarization and injury (lactate dehydrogenase release as well as trypan blue exclusion) in cells that were pretreated with F7 prior to treatment with H(2)O(2). RESULTS: F7 pretreatment significantly attenuated H(2)O(2)-induced ROS production, mitochondrial depolarization and consequent injury in renal proximal tubule cells. CONCLUSION: F7 supplementation might be beneficial for cancer patients in order to prevent renal toxicity of anticancer drug- or cancer progression-related oxidative stress.

Early modification of c-myc, Ha-ras and p53 expressions by chemical carcinogens (DMBA, MNU).

7,12-Dimethylbenz[a]anthracene (DMBA) and N-methyl-N-nitrosourea (MNU) are important environmental carcinogens. Their different biological effects were examined in CBA/Ca H-2(K) haplotype inbred mice on the gene expression of c-myc, Ha-ras and p53 through a 24 hour period. Elevated expression of c-myc and Ha-ras genes was found in the spleen, lung, thymus and lymph nodes 6 and 12 hours after DMBA treatment and in the lung and thymus 3 hours after MNU treatment. In the liver, DMBA induced strong onco/suppressor gene expression as early as 6 hours after the treatment, but MNU increased the p53 gene expression 12 hours after the treatment. The gene expression patterns reflected the different mechanism of the direct acting MNU and metabolically activated DMBA. This phenomenon provides evidence as to the usefulness of detection of onco/supressor key gene expression as early molecular epidemiological biomarkers of carcinogenesis and carcinogenic exposure in animal model, useful in human cancer prevention practice as well.

[Genetic polymorphism in patients with colorectal and with head and neck cancer]. / Allélpolimorfizmusok vizsgálata colorectalis és fej-nyak táji daganatos betegekben.

Colorectal cancer is the second most frequent cause of death among malignant diseases. The mortality of head and neck cancer in Hungary increased by 265 percent in the last thirty years. Both malignancies belong to the most current public health problems in Hungary. The influence of two allelic polymorphisms of GSTM1 and GSTT1, and that of p53 gene codon 72 on colon cancer was investigated. In case of head and neck cancer the effects of the Arg194Trp and Arg399Gln polymorphisms of XRCC1 gene were analyzed. Intraoperative removed tissue samples were processed and cancer free human samples were used as matched controls. The formalin fixed samples were deparaffinized and digested with proteinase K. Genotyping was performed by PCR amplification, and in case of head and neck cancer a PCR-RFLP method was applied. No significant difference was found between tumor patients and controls in the investigated polymorphisms. A significant difference in survival was found between the GSTM1 and p53 gene variants in Dukes'B stage colorectal patients. The survival difference among the XRCC1 194 alleles by head and neck patients in clinical stage III proved to be also significant. The complex analysis of this type of genetic variants may be the future way of the personal risk assessment and the real chance for personal therapy.

GSTM, GSTT and p53 polymorphisms as modifiers of clinical outcome in colorectal cancer.

BACKGROUND: Cancer of the colorectal region is the second most frequent cause of death among malignant diseases. The influence of two allelic polymorphisms of GSTM1 and GSTT1, and that of p53 gene codon 72 on colon cancer was investigated. PATIENTS AND METHODS: Intraoperatively removed tissue samples were processed from colorectal cancer patients. Cancer-free human samples were used as matched controls. Samples were digested with proteinase-K. DNA solution was used for PCR amplification. RESULTS: No significant difference was found between tumor patients and controls in the investigated polymorphisms. A significant association was found in Dukes' B stage patients between the GSTM1 and p53 gene variants and survival. In patients with GSTM1 null genotype and p53 Arg/Pro heterozygotes or Pro/Pro homozygotes the chance of survival is significantly lower than in the case of GSTM1+ and p53 Arg/Arg variants (p=0.009 and p=0.008, respectively). CONCLUSION: The significance of the investigated polymorphisms in prognosis is dependent on the tumor stage. These parameters might be used in certain cases as prognostic biomarkers in clinical diagnostics and in the planning of individual therapy.

The effect of an organized, nationwide breast cancer screening programme on non-organized mammography activities.

OBJECTIVES: To analyse the effect of an organized, nationwide breast cancer screening programme on non-organized mammography activities in Hungary. SETTING: The nationwide dataset of the Hungarian National Health Insurance Fund Administration covering the years 2000-2005. METHODS: Data derived from the nationwide database of the Hungarian National Health Insurance Fund Administration. The study includes all women undergoing mammography before (2000-2001) and after (2002-2003/2004-2005) the introduction of organized screening. RESULTS: The number of women having non-organized (opportunistic/diagnostic) mammograms was around 250,000 in 2000-2001, but increased to 350,000 in 2005. In the age group 45-64 years in 2000-2001, only 27.4% of all women undergoing mammography were examined within locally-organized programmes. After the introduction of the nationwide programme, this percentage increased to 61.0% in 2002-2003, and 56.3% in 2004-2005. After the introduction of the nationwide organized programme (2002-2003), the proportion of organized screening mammographies remained among the highest in county Hajdú-Bihar (78.4%) and Zala (88.3%) and increased significantly in county Vas (87.7%). CONCLUSION: The introduction of an organized nationwide screening programme in Hungary resulted in increases in the number of screening mammographies, and also of non-organized mammographies. Although the ratio of organized screening versus non-organized mammography changed in favour of screening mammographies, there are large within-country differences between counties.

Early modification of c-myc, Ha-ras and p53 expressions by N-methyl-N-nitrosourea.

Methylnitrosourea (MNU) is a well-known pluripotent direct-acting carcinogen. Formation of MNU following incubation of various meats with additional nitrite under in vitro acidic conditions is possible. It is possible that many species, including humans, are exposed to carcinogenic MNU, generated in their alimentary tract. Previously, an animal model was developed by our research group to investigate the expression of three genes c-myc, Ha-ras and p53 as early molecular epidemiological biomarkers of carcinogenic exposure or carcinogenesis caused by DMBA (dimethylbenz[alpha]anthracene). The aim of this study was to investigate the early effect of MNU on the gene expression levels. MNU is a direct-acting carcinogen which spontaneously and rapidly degrades, so any effect on the gene expression is observed in 24 hours. Our results show the maximum effect in vivo on the gene expression at 12 hours after the MNU treatment; on the other hand, 24 hours after the treatment, the elevated gene expressions decreased in target organs (bone marrow, lung, lymph nodes). Our results correspond to "long-term" experiments of the carcinogenic effect of MNU in different target organs. Our findings suggest that MNU has an impact on the expression of c-myc, Ha-ras and p53 genes in 12 hours, especially in bone marrow. Overexpression of these genes occurs as an early biological effect of exposure to chemical carcinogens. According to our results, the high expression of these genes could indicate MNU exposure and these genes could take part in MNU-induced tumorigenesis.

Oncogene and tumor suppressor gene expression changes in the peripheral blood leukocytes of patients with colorectal cancer.

AIMS AND BACKGROUND: The mortality of colorectal cancer continues to stagnate despite the development of new therapeutic approaches. Therefore, identifying high-risk population groups could contribute to the prevention of a considerable part of deaths caused by colorectal tumors. METHODS: Fifty patients with colon cancer and 50 patients with other, nonmalignant diseases were selected for the study. Expression of the c-myc, Ha-ras and p53 genes was determined in the peripheral leukocytes of the participants. RESULTS: Marked elevations of the expression of all three investigated genes were seen in the colon cancer patients when compared to the controls. CONCLUSIONS: Our investigations showed that increases in the expression of c-myc, Ha-ras and p53 genes can be demonstrated in the peripheral leukocytes of colon cancer patients. By applying our method to clinical investigations, individuals with a high risk of having developed colon cancer may be identified and early diagnosis may be established.

[Attendance in the second phase (2004-2005) of the Hungarian organized breast cancer screening program]. / A szervezett emlôszûrési program második ciklusának (2004-2005) részvételi arányai.

AIM: Organised, nationwide screening for breast cancer with mammography in the age group of 45-65 years with a 2-year screening interval started in Hungary in January 2002. The aim of this study is to analyze the attendance rate of breast screening programme, including the analysis of the ratio of screening and diagnostic mammography examinations. DATA AND METHODS: The data derive from the financial database of the National Health Insurance Fund Administration (NHIFA) covering the 6-year period between 2000-2006. The ratio of women in the age group of 45-65 years was calculated having either a screening mammography or a diagnostic mammography. The analysis was carried out for the years 2000-2001 before and 2002-2003, 2004-2005 after the implementation of nationwide organised programme. RESULTS: In the years 2000-2001 7.26% of the women aged 45-65 had an opportunistic screening mammography, while in 2002-2003 34% and in 2004-2005 29.5% of the target population had screening mammography within the organised programme. During the same periods 19.8% (2000-2001), 22.1% (2002-2003) and 23.2% (2004-2005) of women aged 45-65 had a diagnostic mammography. Thus the total (screening and diagnostic) coverage of mammography increased from 26.2% (2000-2001) to 53.5% (2002-2003) and 50.8% (2004-2005). CONCLUSIONS: Attendance of the Hungarian organised breast cancer screening programme slightly declined in 2004-2005, and to achieve the expected results in decline of mortality further improvement of attendance is necessary.

Association between allelic polymorphisms of metabolizing enzymes (CYP 1A1, CYP 1A2, CYP 2E1, mEH) and occurrence of colorectal cancer in Hungary.

BACKGROUND: Genetic polymorphisms of metabolizing enzymes may affect the risk of cancer formation in humans. Since the diet can contain polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HAs), the relationship between polymorphisms of enzymes involved in PAH and HA metabolism and the occurrence of sporadic colorectal cancer was studied. PATIENTS AND METHODS: Five hundred colorectal cancer patients and 500 controls were genotyped for cytochrome P450 enzymes (CYP) 1A1 Ile/Val, CYP 1A2*1F, CYP 2E1 c1/c2, microsomal epoxy hydrolase (mEH) exon 3 Tyr113His and exon 4 His139Arg polymorphisms by allele-specific polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphism (RFLP). RESULTS: The presence of CYP 1A1 Val, CYP 2E1 c2 and mEH exon 3 His alleles was statistically significantly associated with the occurrence of colorectal cancer (OR: 1.44 95% CI: 1.04-2.00; OR: 1.74 95% CI: 1.15-2.65; OR: 1.79 95% CI: 1.10-2.92, respectively). CONCLUSION: These findings suggest that allelic polymorphism of metabolizing enzymes play an important role in human colorectal carcinogenesis by affecting the metabolism of dietary carcinogens.

Prognostic factors in Hungarian breast cancer patients.

BACKGROUND: Breast cancer is the most common cancer among women, with variable outcomes, justifying a continuous search for new parameters to predict accurate prognosis and indicate suitable adjuvant therapy for patients. MATERIALS AND METHODS: Fourty-four stage I-III breast cancer specimens were investigated immunohistochemically for the expression of cyclooxygenase-2 enzyme (COX-2), hormone receptors, tumor suppressor gene p53, oncogene HER2 and proliferation marker Ki-67. Additionally, twelve specimens were also investigated for the presence of the phosphorylated extracellular signal-regulated kinase (pERK). RESULTS: It was demonstrated that expressions of biological markers were related to each other (ER to p53 and Ki-67, COX-2 to ER, PgR, Ki-67 and p53, Ki-67 to p53 and PgR, p53 to PgR). CONCLUSION: Our data indicate that concomitant immunohistochemical evaluation of cyclooxygenase-2, hormone receptors, p53 and Ki-67 may be of clinical value in determining an accurate prognosis.

Effect of a plant-derived natural compound, Flavin7, on the ERK signaling pathway in immortalized mouse proximal tubule cells.

BACKGROUND: Since MAP kinases represent an important pathway of transducing external stimuli to internal signals in cells, determining their possible role in cancer cells may offer a promising way for the treatment and prognosis of malignant diseases. Our previous experiments have shown that a flavonoid-rich solution, Flavin7, was able to diminish kidney tumor growth in vivo. MATERIALS AND METHODS: Effects of Flavin 7 on the MAPK signaling pathway were determined in immortalized mouse proximal tubule cells by determining cell viability, flow cytometric analysis, luciferase assays and Western blots. RESULTS: At a nontoxic dose, Flavin7 markedly reduced phosphorylation of ERK and inhibited activity of its downstream targets such as Elk1 and CREB via inhibition of the ERK-kinase MEK1. CONCLUSION: Because of its ability to temporarily inhibit kidney tumor growth and activation of the MEK1/ERK pathway in vitro, further in vivo investigations may determine the potential role of Flavin7 in the treatment of malignancies.