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.

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.

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.

Enhancement of organ regeneration in animal models by a stem cell-stimulating plant mixture.

Adult stem cells play an important role in the regeneration of damaged organs. Attempts have already been made to enhance stem cell production by cytokines, in order to increase the improvement of cardiac functions after myocardial infarction. In our present study we investigated the possibility whether instead of cytokine injection dietary stimulation of stem cell production accelerates the organ regeneration in animals. A dietary supplement, Olimpiq StemXCell (Crystal Institute Ltd., Eger, Hungary), containing plant extracts (previously proved to increase the number of circulating CD34(+) cells) was consumed in human equivalent doses by the experimental animals. In the first experiment carbon tetrachloride was applied to CBA/Ca mice, to induce liver damage, and liver weights between StemXCell-fed and control animals were compared 10 days after the treatment. In the second model experimental diabetes was induced in F344 rats by alloxan. Blood sugar levels were measured for 5 weeks in the control and StemXCell-fed groups. The third part of the study investigated the effect of StemXCell on cardiac functions. Eight weeks after causing a myocardial infarction in Wistar rats by isoproterenol, left ventricular ejection fraction was determined as a functional parameter of myocardial regeneration. In all three animal models StemXCell consumption statistically significantly improved the organ regeneration (relative liver weights, 4.78 +/-0.06 g/100 g vs. 4.97 +/- 0.07 g/100 g; blood sugar levels at week 5, 16 +/- 1.30 mmol/L vs. 10.2 +/- 0.92 mmol/L; ejection fraction, 57.5 +/- 2.23 vs. 68.2 +/- 4.94; controls vs. treated animals, respectively). Our study confirms the hypothesis that dietary enhancement of stem cell production may protect against organ injuries and helps in the regeneration.

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.

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.

All-trans retinoic acid (ATRA) suppresses transcription of human papillomavirus type 16 (HPV16) in a dose-dependent manner.

Earlier we found that SiHa cervical squamous carcinoma cells that harbor HPV type 16 respond to ATRA treatment in a dose-dependent manner: high-dose (10(-5)-10(-4) M) but not low-dose (10(-7)-10(-6) M) ATRA induced growth arrest. Growth of HPV-infected cells is highly dependent on the expression of the viral E6/E7 proteins. Thus, targeting expression of the viral E6/E7 genes might influence growth properties of HPV-infected cells. Here, we demonstrated that high-dose ATRA inhibited expression of HPV16 E7 through suppression of the HPV16 promoter (p97) activity. Gelshift assay (EMSA) revealed that binding of the AP-1 transcription factor to an oligonucleotide originated from the HPV type 16 promoter was diminished after high-dose, but not low-dose ATRA treatment. This suggests that high-dose ATRA suppresses HPV 16 promoter activity, at least in part, via a decreased AP-1 binding. Our data might be useful in treatment of cervical dysplasias and/or carcinomas.

All-trans-retinoic acid activates caspase-1 in a dose-dependent manner in cervical squamous carcinoma cells.

Earlier we observed that all-trans-retinoic acid (ATRA) dose-dependently suppressed the growth of cervical carcinoma cells. Suppression of growth required sustained activation of interferon regulatory factor 1 (IRF-1), which was achieved by high-dose (10(-4) M), but not low-dose (10(-6) M), ATRA treatment. In this paper we examine the role of IRF-1 in cell death that accompanied the growth suppression in high-dose ATRA-treated cells. We found that high-dose, but not low-dose, ATRA treatment activated caspase-1 in those cervical carcinoma cells. Transient transfection of an antisense-IRF-1 construct diminished high-dose ATRA-mediated caspase-1 activation. On the other hand, ATRA was not able to induce caspase-1 expression in a STAT1 (signal transducer and activator of transcription 1) knockout cell line, but transient transfection of STAT1 restored it. These results suggested the importance of both IRF-1 and STAT1 in high-dose ATRA-induced activation of caspase-1. Our results might be useful in the treatment of retinoid-resistant cervical neoplasias.

Suppression of growth by all-trans retinoic acid requires prolonged induction of interferon regulatory factor 1 in cervical squamous carcinoma (SiHa) cells.

All-trans retinoic acid (ATRA) suppresses growth of cervical dysplasias in vivo, although the sensitivity to retinoids is frequently lost during cervical carcinogenesis. It has been suggested that prolonged treatment or use of higher doses of retinoids might offer favorable response rates. We found SiHa cervical squamous carcinoma cells that were virtually resistant to ATRA-induced growth-inhibitory effects at physiological doses (10(-7 to) 10(-6) M) to be more responsive at pharmacological doses (10(-5 to) 10(-4) M). The growth inhibition by high-dose (10(-4) M) ATRA was associated with a sustained activation of interferon regulatory factor 1 (IRF-1), while a low dose (10(-6) M) of ATRA activated IRF-1 only transiently. Antisense IRF-1 inhibited the high-dose (10(-4) M), ATRA-mediated growth arrest; forced expression of IRF-1 caused a significant reduction in cell growth. High-dose (10(-4) M) ATRA increased binding of NF-kappaB and STAT1 proteins to sequences that originated from the IRF-1 promoter region, while low-dose (10(-6) M) ATRA induced only NF-kappaB binding. A delayed tyrosine phosphorylation of the signal transducer and activator of transcription-1 (STAT1) was observed after high-dose (10(-4) M) but not low-dose (10(-6) M) ATRA treatment. In agreement with this, induction of IRF-1 mRNA by ATRA was only modest and transient in a STAT1 knockout cell line, suggesting the importance of STAT1 in sustained IRF-1 expression. Our data showed that ATRA is capable of inducing dose-dependent cellular changes, which might be appropriate to overcome resistance to retinoids that frequently develops during cervical carcinogenesis.

Effect of rancid corn oil on some onco/suppressor gene expressions in vivo. A short-term study.

Autooxidation of polyunsaturated fatty acids (PUFAs) of edible oils results in the formation of fatty acid hydroperoxides that can undergo further chemical transformations to yield a variety of re-arranged and chain-cleavage products. Since the oxidation products of PUFAs have been reported to have cytotoxic and mutagenic effects, the consumption of rancid oils and fats represents a possible health hazard for the population. Storage of corn oil at room temperature and in the refrigerator for a forty-eight month period resulted in two different qualities of oil samples, which were characterized by UV, titrimetric (peroxide value, acid value) and GC-MS methods. Earlier it was demonstrated that the increase of expression of certain oncogenes and tumor suppressor genes is a method of choice for the early detection of carcinogen exposure. Treatment of CBA/Calpha inbred mice with the two oil samples showed significantly increased expression of the Ha-ras gene in all the investigated organs (liver, lung, kidney, thymus and spleen) of the rancid corn oil-treated animals. Expression of the c-myc and the p53 genes was also increased after the rancid corn oil-treatment in all the organs but the thymus of the mice. The results suggest that rancid oils, rich in omega-6 unsaturated fatty acids, could be involved not only in tumor promotion but in initiation as well.