Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0596263 (carcinogenesis)
 64,820 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Potential inhibitory effects of the antiangiogenic drug TNP-470 on rat urinary bladder carcinogenesis were investigated in F344 male rats initiated with 0.05% BBN in the drinking water for 8 weeks. Group 1 was then continuously treated with TNP-470 by subcutaneous injection using osmotic minipump until the end of the experiment; group 2 served as the control with only initiation. The incidences and multiplicities of papillomas and carcinomas in the TNP-470-treated group were significantly decreased compared to the control group values along with the tumor vascular density. In conclusion, TNP-470 can inhibit rat urinary bladder carcinogenesis, presumably through its effects on angiogenesis.
Asian Pac J Cancer Prev
PMID:Inhibition of rat urinary bladder carcinogenesis by the antiangiogenic drug TNP-470. 1662 25

In this communication, we document chemopreventive effects of Butea monosperma extract on hepatic carcinogenesis and on tumor promoter induced markers and oxidative stress in male Wistar rats. Treatment of male Wistar rats for five consecutive days with 2-AAF i.p. induced significant hepatic toxicity, oxidative stress and hyperproliferation. Pretreatment of B.monosperma extract (100 and 200 mg/kg body weight) prevented oxidative stress by restoring the levels of antioxidant enzymes and also prevented toxicity at both doses. The promotion parameters induced (ornithine decarboxylase activity and DNA synthesis) by 2-AAF administration in diet with partial hepatectomy (PH) were also significantly suppressed dose dependently by B. monosperma. Thereafter, we proceeded with studies on rat liver carcinogenesis. After fourteen days of DEN treatment, dietary administration of 2-AAF with PH resulted in a 100% incidence of tumors in the animals. However, B.monosperma caused reduction in the number of tumors/ rat and percentage of tumor bearing rats at the end of the study, as confirmed histologically. Thus, our data suggest that B.monosperma extract is a potent chemopreventive agent which suppresses 2-AAF-induced hepatic carcinogenesis and oxidative damage in Wistar rats. The protective activity of the plant might be due to the two major constituents (butrin and isobutrin).
Asian Pac J Cancer Prev
PMID:Chemoprevention by Butea monosperma of hepatic carcinogenesis and oxidative damage in male wistar rats. 1662 33

Phenobarbital (PB), a rodent non-genotoxic carcinogen, showed hormesis, biphasic effects on rat liver carcinogenesis. To test the hypothesis that the hormesis earlier observed for PB induced hepatocarcinogenesis might also exist in the TGF-alpha transgenic mice model, one which is highly susceptible to carcinogenesis, the carcinogenic or promotion effects of a wide range of phenobarbital (PB) concentrations were investigated. Two weeks after a single i.p. dose of 5 mg /kg bw of diethylnitrosamine (DEN) to 15 day old mice, animals were treated with diet containing PB at doses of 0, 2, 15 or 500 ppm. The incidence and multiplicity of tumors, including hepatocellular adenomas and carcinomas, were significantly increased by the high dose of PB, but no significant difference among the groups receiving 2 and 15 ppm for liver tumors when compared to DEN alone group. The proliferating cell nuclear antigen indices for liver tumors and surrounding hepatocytes in high dose PB treated mice were significantly increased, but no change was noted at the lower doses. The total cytochrome P450 content in the liver was also elevated by 500 ppm of PB, while hepatic 8-OHdG levels demonstrated no significant change. In conclusion, PB at high dose enhances DEN-induced hepatocarcinogenesis in TGF-alpha transgenic mice, but low doses lack any significant effects. One possible mechanism of phenobarbital carcinogenicity might be influenced by cytochrome P450 system exhibiting a strong promoting activity for liver of mice.
Asian Pac J Cancer Prev
PMID:Lack of promoting effects of phenobarbital at low dose on diethylnitrosamine-induced hepatocarcinogenesis in TGF-alpha transgenic mice. 1683 22

The present investigation was undertaken to explore the anti-tumor promoting activity of Rosemarinus officinalis on two-stage skin carcinogenesis, induced by a single topical application of 7, 12-dimethylbenz(a)anthracene and promoted by treatment of croton oil for 15 weeks in Swiss albino mice. Oral administration of Rosemary leaf extract at a dose of 1,000 mg/ kg b. wt. / day at pre, peri and post-initiational phases, was found to be effective in decreasing the tumor incidence (50, 41.7, 58.3%, respectively) in comparison to the control (100%). Furthermore, the cumulative number of papillomas, tumor yield and tumor burden were also found to be reduced in R. officinalis-treated animals. This was associated with significant alteration in liver lipid peroxidation and glutathione (GSH) levels.
Asian Pac J Cancer Prev
PMID:Modulatory influence of Rosemarinus officinalis on DMBA-induced mouse skin tumorigenesis. 1683 34

The purpose of the present study was to examine whether Neem leaf (Azadirachta indica) has short-term chemopreventive effects on endpoint preneoplastic lesions involved in rat colon carcinogenesis and might also exert antioxidative activity. Forty- two male F344 rats were randomly divided into 6 experimental groups. Groups 1 to 4 were given a subcutaneous injection of azoxymethane (AOM, 20 mg/kg body weight) once a week for 2 weeks. Starting one week before the first injection of AOM, rats in groups 2 to 4 received an aqueous extract of Neem leaf (20, 100, and 250 mg/kg, respectively) by gavage 3 times per week, for 5 weeks. Rats in group 5 also were given the Neem extract by gavage feeding 3 times per week for 5 weeks, while group 6 served as untreated controls. The experiment was terminated 5 weeks after the start. Dietary feeding of the Neem extract at all dose levels significantly inhibited the induction of aberrant crypt foci (ACF) (P<0.0002), when compared to the AOM-treated group (group 1). In groups 2 to 4, treatment of rats with the Neem extract also significantly decreased the proliferating cell nuclear antigen (PCNA) labeling indices (P<0.0006) of colon epithelium and ACF. Moreover, the Neem extract also showed antioxidative activity. The finding that dietary Neem has possible chemopreventive effects in the present short-term colon carcinogenesis bioassay suggests that longer-term exposure may cause suppression of tumor development.
Asian Pac J Cancer Prev
PMID:Antioxidative and modifying effects of a tropical plant Azadirachta indica (Neem) on azoxymethane-induced preneoplastic lesions in the rat colon. 1705 47

It is widely reported that reactive oxygen species (ROS) cause apotosis and carcinogenesis. Marked infiltration of activated leukocyte and enhanced production of ROS appear to occur in the gastric mucosa infected with Helicobacter pylori (H. pylori). The previous studies reported that the mutation of the succinate dehydrogenase subunit C (SDHC) gene caused the increase in superoxide anion (O(2)(-)) and oxidative stress. To extend these findings, we epidemiologically investigated the association of a SDHC polymorphism at 3'-untranslated region of exon 6 (JST173800) with H. pylori infection, gastric atrophy and gastric cancer risk in Japan. The subjects consisted of 454 health checkup examinees without a history of cancer and 202 gastric cancer patients. The SDHC polymorphism was not associated with H. pylori infection seropositivity, gastric atrophy, and cancer risk in this study. Although the polymorphism at the 3'-untranslated region could be hypothesized to be functional, this study did not demonstrate any significant association of the SDHC gene polymorphism with gastric atrophy and cancer.
Asian Pac J Cancer Prev
PMID:No association of an SDHC gene polymorphism with gastric cancer. 1725 Apr 22

Many chemopreventive agents appear to target signaling intermediates in apoptosis-inducing pathways. Inherently, the process of neoplastic conversion selects against apoptosis to initiate, promote, and perpetuate the malignant phenotype. Thus, targeting apoptosis pathways in pre-malignant cells, in which these pathways are still relatively intact, may be an effective module of cancer prevention. Diallyl sulfide (DAS), a naturally occurring organosulfide, present in garlic, is reported to have pleiotropic biological effects. DAS is known to inhibit chemically induced tumors in a number of in vivo and in vitro studies. The aberration of tumor suppressor gene, p53 and the ras oncogene have been linked to the induction of multiple signaling pathways and to the resistance offered by cancer cells to the apoptosis. Therefore, the present study was carried out to investigate the role of DAS on modulation of multiple p53 and ras-induced signaling pathways in 7,12-dimethylbenathacene (DMBA) induced skin carcinogenesis. The results showed that DAS up regulates expression of tumor suppressor protein p53 (wt p53) and its downstream target molecule p21/waf1. Proapoptotic protein, bax was upregulated by DAS supplementation. An opposite trend was observed in DMBA induced antiapoptotic proteins expressions, survivin and bcl-2, which were significantly downregulated by DAS supplementation. In the present study we also demonstrated that DAS supplementation significantly reduces the expression of ras oncoprotein and to modulate expression of its signaling molecules including PI3K/Akt and MAPKs. Western blot analysis demonstrated that DAS significantly reduced the DMBA induced protein expressions of PI3K/Akt and p38MAPK. However, DAS supplementation did not alter the expression JNK1 and ERK1/2. Thus, our results confirm that DAS can adopt a multi-prong strategy to target multiple signaling pathways leading to induction of apoptosis and inhibition of growth of DMBA induced skin tumors in Swiss albino mice. Although studies of single pathways have been helpful in guiding investigations, new tools to study the integration and multiplicity of signaling pathways hold the hope of improved understanding of the signaling pathway alterations in cancer chemoprevention by naturally occurring compounds.
Asian Pac J Cancer Prev
PMID:Involvement of multiple signaling pathways in diallyl sulfide mediated apoptosis in mouse skin tumors. 1725 Apr 26

Reactive oxygen species cause damage to proteins, lipids and DNA. Coenzyme Q10 (CoQ10) is a compound with mitochondrial bioenergetic functions. The reduced form of CoQ10 shows antioxidant activity. In the present study, effects of CoQ10 on development of azoxymethane (AOM)-induced aberrant crypt foci (ACF) and mucin-depleted foci (MDF) in F344 male rats were investigated. To induce ACF and MDF, 6-week old rats were given two weekly subcutaneous injections of AOM (15 mg/kg body weight) and also received a control diet or experimental diets containing CoQ10 (200 or 500 ppm) for 4 weeks, starting one day before the first dose of AOM. At 10 weeks of age, all animals were sacrificed and their colons were evaluated for numbers and sizes of ACF and MDF. Administration of 200 and 500 ppm CoQ10 resulted in reduction of ACF numbers, to 77% and 68% of the carcinogen control value, respectively. The percentages of ACF consisting of more than 4 crypts in these groups were also significantly lower than in the controls. Treatment with 500 ppm CoQ10 furthermore decreased the number of sialomucin-producing ACF and MDF per colon to 42% and 38% of the carcinogen control value without CoQ10, respectively. These results suggest that CoQ10 may be an effective chemopreventive agent against colon carcinogenesis.
Asian Pac J Cancer Prev
PMID:Suppression of azoxymethane-induced colonic premalignant lesion formation by coenzyme Q10 in rats. 1725 Apr 35

We examined the modifying effect of freeze-dried whole-leaf Aloe arborescens Miller var. natalensis Berger (Kidachi aloe in Japan; designated as 'ALOE') on azoxymethane (AOM)-induced intestinal carcinogenesis in rats. Male F344 rats (4 weeks old) were fed basal diet or experimental diet containing 0.2% or 1% ALOE for 28 weeks. Starting two weeks later, the animals received subcutaneous injections of AOM once weekly for 10 weeks. The incidence of colorectal adenocarcinomas in the 0.2% (but not 1%) ALOE group showed a strong tendency for decrease (p = 0.056) from the control group. Further, the adenocarcinoma incidence in the entire intestine (small and large intestines) in the 0.2% ALOE group was significantly (p = 0.024) decreased compared to the control value. However, there were no significant differences in tumor multiplicities of colorectal or entire intestines among the 3 groups. In addition, we also studied the safety of long-term ingestion of ALOE as a health food or natural thickening stabilizer. Rats were fed the basal diet or 1% ALOE diet for 35 weeks without AOM treatment. Feeding with 1% ALOE did not affect most hematological and serum biochemical parameters in the rats. These results indicate that a low level of ALOE ingestion might have a mild suppressive effect on intestinal tumor growth without harmful side effects.
Asian Pac J Cancer Prev
PMID:Effects of aloe arborescens ingestion on azoxymethane-induced intestinal carcinogenesis and hematological and biochemical parameters of male F344 rats. 1725 Apr 32

Not only the incidence but the mortality of breast cancer has been steadily increasing in Korea over the last twenty years, and it became the most common female neoplasm in 2002. In fact, the increase in the rate of breast cancer mortality in Korea over the past 10 years has been higher than anywhere else in the world, and it is particularly noteworthy that more than half of the incident cases occur among those younger than 50 years of age. The rapid westernization of dietary habits and changes in reproductive behavior of Korean women presumably played a central role in this extraordinary increase in breast cancer occurrence. A large-scale multi-center case-control analysis showed that an older age, a family history of breast cancer, early menarche, late menopause, late full-term pregnancy, never-having had a breast-fed child, and postmenopausal obesity are breast cancer risk factors in Korea. Environmental and genetic factors are known to play interactive roles in human carcinogenesis and recent studies have shown that genetic polymorphisms may predispose individuals to breast cancer via gene-to-environment or gene-to-gene interactions. Thus research into genetic variation in xenobiotic metabolism, estrogen metabolism, DNA repair, cytokine metabolism, or cell cycle control may give insights into both the etiology and prevention of breast cancer. Epidemiologic evidence obtained from migrant and lifestyle change studies and investigations of main risk factors strongly suggests that breast cancer will further increase in Korea. Future predictions point to a 2- to 3-fold increase in incidence by 2020. Here, we briefly introduce health education programs and breast cancer campaigns, in the broad context of the Korean National Cancer Control Program.
Asian Pac J Cancer Prev
PMID:Lifestyle, genetic susceptibility and future trends of breast cancer in Korea. 1725 Apr 52


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