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1.
It is becoming increasingly evident that cancer stem cells play a vital role in development and progression of cancers and relapse following chemotherapy. The present study examines the presence of cancer stem-like cells (CSC) in adenomatous polyps and in normal appearing colonic mucosa in humans during aging. The number of polyps was found to increase linearly with advancing age (r2 = 0.92, p < 0.02). Immunohistochemical analysis revealed co-localization of CSC markers CD44 and CD166 in colonic polyps. Real-time RT-PCR analysis of normal appearing mucosa from subjects with adenomatous polyps showed an age-related rise in CSC as evidenced by the increased expression of CD44, CD166 and ESA. A similar phenomenon was also observed for EGFR. In addition, the expression each CSC marker was found to be about 2-fold higher in subjects with 3–4 polyps than those with 1–2 polyps. In conclusion, our results show that colon cancer stem-like cells are present in the premalignant adenomatous polyps as well in normal appearing colonic mucosa. Moreover, our observation of the age-related rise in CSC in macroscopically normal colonic mucosa suggests a predisposition of the organ to developing colorectal cancer.  相似文献   

2.
Clopidogrel is a prodrug used widely as a platelet aggregation inhibitor. After intestinal absorption, approximately 90% is converted to inactive clopidogrel carboxylate and 10% via a two-step procedure to the active metabolite containing a mercapto group. Hepatotoxicity is a rare but potentially serious adverse reaction associated with clopidogrel. The aim of this study was to find out the mechanisms and susceptibility factors for clopidogrel-associated hepatotoxicity. In primary human hepatocytes, clopidogrel (10 and 100 μM) was cytotoxic only after cytochrome P450 (CYP) induction by rifampicin. Clopidogrel (10 and 100 μM) was also toxic for HepG2 cells expressing human CYP3A4 (HepG2/CYP3A4) and HepG2 cells co-incubated with CYP3A4 supersomes (HepG2/CYP3A4 supersome), but not for wild-type HepG2 cells (HepG2/wt). Clopidogrel (100 μM) decreased the cellular glutathione content in HepG2/CYP3A4 supersome and triggered an oxidative stress reaction (10 and 100 µM) in HepG2/CYP3A4, but not in HepG2/wt. Glutathione depletion significantly increased the cytotoxicity of clopidogrel (10 and 100 µM) in HepG2/CYP3A4 supersome. Co-incubation with 1 μM ketoconazole or 10 mM glutathione almost completely prevented the cytotoxic effect of clopidogrel in HepG2/CYP3A4 and HepG2/CYP3A4 supersome. HepG2/CYP3A4 incubated with 100 μM clopidogrel showed mitochondrial damage and cytochrome c release, eventually promoting apoptosis and/or necrosis. In contrast to clopidogrel, clopidogrel carboxylate was not toxic for HepG2/wt or HepG2/CYP3A4 up to 100 µM. In conclusion, clopidogrel incubated with CYP3A4 is associated with the formation of metabolites that are toxic for hepatocytes and can be trapped by glutathione. High CYP3A4 activity and low cellular glutathione stores may be risk factors for clopidogrel-associated hepatocellular toxicity.  相似文献   

3.
《Cancer epidemiology》2014,38(4):408-413
Background and aimPrevious evidence has shown that microRNA (miR)-224 may function as an onco-miRNA in hepatocellular carcinoma (HCC) cells by activating AKT signaling. However, little is known about the clinical significance of the combined expression of miR-224 and phosphorylated-AKT (pAKT) on human HCC. The aim of this study was to investigate the synergistical influence of miR-224 and pAKT on clinical characteristics and prognosis in patients with HCC.MethodsOne-hundred and thirty HCC patients who had undergone curative liver resection were selected. In situ hybridization and immunohistochemistry were respectively performed to detect the expression of miR-224 and pAKT in the respective tumors.ResultsCompared with the adjacent nonneoplastic liver tissues, the expression levels of miR-224 and pAKT protein in HCC tissues were both significantly increased (both P < 0.001). In addition, the combined upregulation of miR-224 and pAKT protein was significantly associated with serum AFP (P = 0.01), tumor stage (P = 0.002) and tumor grade (P = 0.008). Moreover, HCC patients highly expressing both miR-224 and pAKT protein had worse 5-year disease-free survival and 5-year overall survival (both P < 0.001). Furthermore, the Cox proportional hazards model showed that the combined upregulation of miR-224 and pAKT protein (miR-224-high/pAKT-high) may be independent poor prognostic factors for both 5-year disease-free survival (P = 0.008) and 5-year overall survival (P = 0.01) in HCC.ConclusionThese results indicate for the first time that miR-224 upregulation and AKT activation may synergistically associate with tumor progression of HCC. The combined high expression of miR-224 and pAKT may be a potential indicator for predicting unfavorable prognosis in HCC patients.  相似文献   

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Centrosomal proteins have been implicated in the progression of human diseases. CEP131 plays important roles in centrosome duplication and genome stability, but its role in cancers remains largely unknown. Here, we showed that CEP131 expression was increased in hepatocellular carcinoma (HCC), compared to the paracarcinoma tissues, at both mRNA and protein levels. High CEP131 expression was closely associated with tumor size (P = 0.020), tumor capsule (P = 0.043), TNM stage (P = 0.007) and tumor differentiation (P = 0.019). Furthermore, patients with high expression of CEP131 were accompanied with worse overall and disease-free survivals in our and TCGA cohorts consisting of a total of 802 cases. The prognostic value of CEP131 was further confirmed by stratified survival analysis. Multivariate cox regression model indicated that CEP131 was an independent factor for overall survival (hazard ratio = 1.762, 95% confident interval: 1.443–2.151, P < 0.001). In vitro data demonstrated that nucleophosmin (NPM) physically bound to CEP131 and maintained its protein stability. Overexpression of CEP131 in HCC cell lines enhanced cell proliferation and migration, whereas the knockdown of CEP131 led to the opposite phenotypes. Further studies demonstrated that CEP131 exhibited oncogenic activity via activation of PI3K/AKT signaling pathway. Taken together, our findings suggest CEP131 serves as a potential prognostic biomarker in HCC, and functions as an oncogene in this deadly disease.  相似文献   

6.
《Cancer epidemiology》2014,38(5):523-527
PurposeStatins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) are medications widely prescribed to reduce cholesterol levels. Observational studies in high-risk populations, mostly in Asia, have suggested that statins are associated with a reduced risk of hepatocellular carcinoma (HCC). The current study sought to evaluate the association of statin use and HCC in a U.S.-based, low-risk, general population.MethodsA nested case–control study was conducted among members of the Health Alliance Plan HMO of the Henry Ford Health System enrolled between 1999 and 2010. Electronic pharmacy records of statin use were compared among tumor registry-confirmed cases of HCC (n = 94) and controls (n = 468) matched on age, sex, diagnosis date, and length of HMO enrolment.ResultsIn multivariate analyses, ever-use of statins was significantly inversely associated with development of HCC (Odds ratio (OR): 0.32, 95%CI: 0.15–0.67). No clear dose–response relationship was evident as statin use for <2 years (OR = 0.32, 95%CI = 0.13–0.83) and >2 years (OR = 0.31, 95CI% = 0.12–9.81) resulted in very similar ORs.ConclusionsThe use of statins among populations in low-risk HCC areas may be associated with decreased risk of HCC.  相似文献   

7.
In the course of breast cancer global gene expression studies, we identified an uncharacterized gene known as RHBDD2 (Rhomboid domain containing 2) to be markedly over-expressed in primary tumors from patients with recurrent disease. In this study, we identified RHBDD2 mRNA and protein expression significantly elevated in breast carcinomas compared with normal breast samples as analyzed by SAGE (n = 46) and immunohistochemistry (n = 213). Interestingly, specimens displaying RHBDD2 over-expression were predominantly advanced stage III breast carcinomas (p = 0.001). Western-blot, RT-PCR and cDNA sequencing analyses allowed us to identify two RHBDD2 alternatively spliced mRNA isoforms expressed in breast cancer cell lines. We further investigated the occurrence and frequency of gene amplification and over-expression affecting RHBDD2 in 131 breast samples. RHBDD2 gene amplification was detected in 21% of 98 invasive breast carcinomas analyzed. However, no RHBDD2 amplification was detected in normal breast tissues (n = 17) or breast benign lesions (n = 16) (p = 0.014). Interestingly, siRNA-mediated silencing of RHBDD2 expression results in a decrease of MCF7 breast cancer cells proliferation compared with the corresponding controls (p = 0.001). In addition, analysis of publicly available gene expression data showed a strong association between high RHBDD2 expression and decreased overall survival (p = 0.0023), relapse-free survival (p = 0.0013), and metastasis-free interval (p = 0.006) in patients with primary ER-negative breast carcinomas. In conclusion, our findings suggest that RHBDD2 over-expression behaves as an indicator of poor prognosis and may play a role facilitating breast cancer progression.  相似文献   

8.
Background: Tumor necrosis factor-α (TNF-α) is a pro-inflammatory cytokine that may act as an endogenous tumor promoter. A genetic polymorphism of TNF-α gene at position ?308 promoter region is involved in the regulation of expression level and has been found to be associated with susceptibility to various types of cancer. Methods: To determine the association of the TNF-α gene G-308A polymorphism on the risk of hepatocellular carcinoma (HCC) in a Turkish population, a hospital-based case-control study was designed consisting of 110 diagnosis subjects with hepatocellular carcinoma and 110 cancer-free control subjects matched on age, gender, smoking and alcohol status. The genotype frequency of this polymorphism was determined by using a polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) assay. Results: The distribution G-308A genotype was significantly associated with the risk of HCC (p < 0.001, odds ratio [OR] = 4.75, 95% confidence interval [CI] = 2.25–9.82 for ?308 AA/GA genotypes versus GG genotype). Conclusion: We suggested that the presence of the high producer allele ?308A in the TNF-α gene appears to be associated with an increased risk for the development of HCC in Turkish population.  相似文献   

9.
《Phytomedicine》2014,21(2):155-158
Phytoestrogens are popular alternatives to estrogen therapy however their effects on hemostasis in post-menopausal women are unknown. The aim of this study was to determine the effect of the phytoestrogens, genistein, daidzein and equol on the expression of key genes from the hemostatic system in human hepatocyte cell models and to determine the role of estrogen receptors in mediating any response seen. HepG2 cells and Hep89 cells (expressing estrogen receptor alpha (ERα)) were incubated for 24 h with 50 nM 17β-estradiol, genistein, daidzein or equol. Tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), Factor VII, fibrinogen γ, protein C and protein S mRNA expression were determined using TaqMan PCR. Genistein and equol increased tPA and PAI-1 expression in Hep89 cells with fold changes greater than those observed for estradiol. In HepG2 cells (which do not express ERα), PAI-1 and tPA expression were unchanged. Increased expression of Factor VII was observed in phytoestrogen treated Hep89 cells but not in similarly treated HepG2s. Prothrombin gene expression was increased in equol and daidzein treated HepG2 cells in the absence of the classical estrogen receptors. These data suggest that phytoestrogens can regulate the expression of coagulation and fibrinolytic genes in a human hepatocyte cell line; an effect which is augmented by ERα.  相似文献   

10.
Background: The let-7 family plays a vital role in the normal cellular activity of liver cells and the carcinogenesis of hepatocellular carcinoma (HCC). In the previous study, we have detected the association between single nucleotide polymorphisms (SNPs) in the promoter region of let-7 and susceptibility to HCC. However, it is still unknown whether these polymorphisms are associated with HCC prognosis. Methods: We investigated the effect of two potentially functional SNPs in the promoter region of let-7 family, rs10877887 (T > C) and rs13293512 (T > C), on the overall survival of 331 HCC patients. Log-rank test and Cox proportional hazard models were used for the survival analyses. Results: We found that HCC patients carrying the C allele of rs10877887 had a significantly increased death risk (adjusted HR = 1.22, 95%CI = 1.02–1.47, P = 0.03 in the additive model), compared to those with T allele. In the stratified analysis, the risk effect was evident in HCC patients with Barcelona Clinic Liver Cancer (BCLC) stage B (adjusted HR = 1.24, 95%CI = 1.02–1.51, P = 0.03) and in those who received chemotherapy or intervention (adjusted HR = 1.25, 95%CI = 1.02–1.53, P = 0.04). Conclusions: Our results suggest that rs10877887 in the promoter region of let-7 may be a prognostic biomarker for HCC patients, which need the validation from other larger studies in different populations.  相似文献   

11.
Thioredoxin reductase 1 (TrxR1) is a selenocysteine-containing redox-active enzyme that is thought to be important during carcinogenesis. We have recently shown that treatment with statins, HMGCoA reductase inhibitors, reduces the levels of TrxR1 in liver of both rat and human. The reduced TrxR1 levels were correlated with inhibited hepatocarcinogenesis in a rat model. The aim of the present study was to investigate if statins affect the activity of the human TXNRD1 core promoter, which guides expression of TrxR1, and if the effects by statins on TrxR1 expression in liver could be reproduced in a cellular model system. We found that simvastatin and fluvastatin decreased cellular TrxR activity in cultured human liver-derived HepG2 cells with approximately 40% (p < 0.05). Simvastatin, but not fluvastatin or atorvastatin, also reduced the TXNRD1 promoter activity in HepG2 cells by 20% (p < 0.01). In line with this result, TrxR1 mRNA levels decreased with about 25% in non-transfected HepG2 cells upon treatment with simvastatin (p < 0.01). Concomitant treatment with mevalonate could not reverse these effects of simvastatin, indicating that other mechanisms than HMGCoA reductase inhibition was involved. Also, simvastatin did not inhibit sulforaphane-derived stimulation of the TXNRD1 core promoter activity, suggesting that the inhibition by simvastatin was specific for basal and not Nrf2-activated TrxR1 expression. In contrast to simvastatin, the two other statins tested, atorvastatin or fluvastatin, did not influence the TrxR1 mRNA levels. Thus, our results reveal a simvastatin-specific reduction of cellular TrxR1 levels that at least in part involves direct inhibitory effects on the basal activity of the core promoter guiding TrxR1 expression.  相似文献   

12.
Background: Lost or downexpression of the gene deleted in liver cancer 1 (DLC1) has been implicated in the development of hepatocellular carcinoma (HCC). We examined the relationship between DLC1 polymorphisms and HCC risk among Chinese. Methods: Three DLC1 polymorphisms, Ex11 + 255T > G (rs3739298), Ex11-620G > A (rs532841) and IVS19 + 108C > T (rs621554), were genotyped in 434 patients with HCC and 480 controls by PCR-RFLP. The associations with the susceptibility to HCC were evaluated while controlling for confounding factors. Results: We observed significantly increased susceptibility to HCC for the C/C genotype compared with T/T of IVS19 + 108C > T in the HBV carriers (OR = 2.95, 95% CI, 1.65–5.26, P < 0.001). Compared with the haplotype G-A-T (in order of Ex11 + 255T > G, Ex11-620G > A and IVS19 + 108C > T), the haplotype T-G-C was also significantly associated with an increased susceptibility to HCC among HBV carriers (OR = 2.16, 95% CI, 1.08–4.35, P = 0.009). The stratified analysis indicated no modification of the confounding factors on the increased susceptibility to HCC related to the DLC1 polymorphism/haplotype. Conclusions: Our findings suggest that DLC1 genetic polymorphism or haplotype play a role in mediating the susceptibility to HBV-related HCC.  相似文献   

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14.
Animal venoms and toxins are potential bioresources that have been known to mankind as a therapeutic tool for more than a century through folk and traditional medicine. The purified “disintegrin protein” (64 kDa) from the venom of the Indian cobra snake (Naja naja) exhibited cytotoxic effects of various types of human cancer cell lines such as breast cancer (MCF-7), lung cancer (A549) and liver cancer (HepG2). In vitro cytotoxicity, DNA fragmentation, an apoptotic assay and a cell cycle analysis were performed to evaluate the anticancer activity of disintegrin against the above cell lines. The IC50 value of disintegrin was determined to be 2.5 ± 0.5 μg/mL, 3.5 ± 0.5 μg/mL, and 3 ± 0.5 μg/mL for the MCF-7, A549 and HepG2 cell lines respectively. Moreover, the increased distribution of G0/G1 and S phase led to decreased populations of cells in the G2/M phase of MCF-7, HepG2 and A549 cells.  相似文献   

15.
16.
《Cellular signalling》2014,26(12):2773-2781
Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor in adults with median survival time of 14.6 months. A small fraction of cancer stem cells (CSC) initiate and maintain tumors thus driving glioma tumorigenesis and being responsible for resistance to classical chemo- and radio-therapies. It is desirable to identify signaling pathways related to CSC to develop novel therapies to selectively target them. Transient receptor potential cation channel, subfamily M, member 7, also known as TRPM7 is a ubiquitous, Ca2 + and Mg2 + permeable ion channels that are special in being both an ion channel and a serine/threonine kinase. In studies of glioma cells silenced for TRPM7, we demonstrated that Notch (Notch1, JAG1, Hey2, and Survivin) and STAT3 pathways are down regulated in glioma cells grown in monolayer. Furthermore, phospho-STAT3, Notch target genes and CSC markers (ALDH1 and CD133) were significantly higher in spheroid glioma CSCs when compared with monolayer cultures. The results further show that tyrosine-phosphorylated STAT3 binds and activates the ALDH1 promoters in glioma cells. We found that TRMP7-induced upregulation of ALDH1 expression is associated with increases in ALDH1 activity and is detectable in stem-like cells when expanded as spheroid CSCs. Finally, TRPM7 promotes proliferation, migration and invasion of glioma cells. These demonstrate that TRPM7 activates JAK2/STAT3 and/or Notch signaling pathways and leads to increased cell proliferation and migration. These findings for the first time demonstrates that TRPM7 (1) activates a previously unrecognized STAT3  ALDH1 pathway, and (2) promotes the induction of ALDH1 activity in glioma cells.  相似文献   

17.
Acacia species are multipurpose trees, widely used in the traditional systems of medicine to treat various ailments. The major objective of the present study was to determine the gene expression of enzymatic antioxidants by acetone extract from the stem bark of three Acacia species (Acacia dealbata, Acacia ferruginea and Acacia leucophloea) in hydrogen peroxide (H2O2)-induced human hepatoma (HepG2) cells. The expression of antioxidant enzymes such as superoxide dismutase containing copper–zinc (CuZnSOD)/manganese (MnSOD), catalase (CAT) and glutathione peroxidase (GPx) in HepG2 cells was evaluated by real-time PCR. The results of antioxidant enzyme expression in real-time PCR study revealed that the H2O2 (200 μM) challenged HepG2 cells reduced the expression of enzymes such as SOD, GPx and CAT. However, the cells pre-treated with acetone extracts of all the three Acacia species significantly (P > 0.05) up-regulated the expression of antioxidant enzymes in a concentration dependent manner (25, 50 and 75 μg/mL). In conclusion, the findings of our study demonstrated that the acetone extract of Acacia species effectively inhibited H2O2 mediated oxidative stress and may be useful as a therapeutic agent in preventing oxidative stress mediated diseases.  相似文献   

18.
The aim of this study is to characterize the function of mitochondria and main energy fluxes in human colorectal cancer (HCC) cells. We have performed quantitative analysis of cellular respiration in post-operative tissue samples collected from 42 cancer patients. Permeabilized tumor tissue in combination with high resolution respirometry was used.Our results indicate that HCC is not a pure glycolytic tumor and the oxidative phosphorylation (OXPHOS) system may be the main provider of ATP in these tumor cells. The apparent Michaelis–Menten constant (Km) for ADP and maximal respiratory rate (Vm) values were calculated for the characterization of the affinity of mitochondria for exogenous ADP: normal colon tissue displayed low affinity (Km = 260 ± 55 μM) whereas the affinity of tumor mitochondria was significantly higher (Km = 126 ± 17 μM). But concurrently the Vm value of the tumor samples was 60–80% higher than that in control tissue. The reason for this change is related to the increased number of mitochondria. Our data suggest that in both HCC and normal intestinal cells tubulin β-II isoform probably does not play a role in the regulation of permeability of the MOM for adenine nucleotides.The mitochondrial creatine kinase energy transfer system is not functional in HCC and our experiments showed that adenylate kinase reactions could play an important role in the maintenance of energy homeostasis in colorectal carcinomas instead of creatine kinase.Immunofluorescent studies showed that hexokinase 2 (HK-2) was associated with mitochondria in HCC cells, but during carcinogenesis the total activity of HK did not change. Furthermore, only minor alterations in the expression of HK-1 and HK-2 isoforms have been observed.Metabolic Control analysis showed that the distribution of the control over electron transport chain and ATP synthasome complexes seemed to be similar in both tumor and control tissues. High flux control coefficients point to the possibility that the mitochondrial respiratory chain is reorganized in some way or assembled into large supercomplexes in both tissues.  相似文献   

19.
《Cancer epidemiology》2014,38(6):679-685
BackgroundDuring the last 20 years, relevant diagnostic procedures and advanced treatments have been progressively introduced in the management of hepatocellular carcinoma (HCC).The aim of the present study was to assess up-to-date survival trends for HCC in southern Switzerland, a region with one of the highest incidence rates in the country.MethodsHCCs diagnosed in 1996–2009 were selected by the Ticino Cancer Registry. Cancer-specific survival (CSS) analysis was performed using the Kaplan–Meier method by calendar period: 1996–2000, 2001–2005 and 2006–2009. The log-rank test was used to detect differences in survival curves. Simultaneous assessment of prognostic factors was performed by a multivariate analysis using the Cox proportional-hazards regression model.Results619 HCCs were analysed. There was a significant increase of patients undergoing transarterial chemoembolisation (TACE), whereas patients undergoing curative or palliative supportive treatments remained unchanged (p < 0.0001). No shift to earlier stages was detected. Significant differences in CCS were observed by age-group (p < 0.0001), diagnosis period (p < 0.0001), diagnosis technique (p = 0.0035), Barcelona-Clinic liver cancer stage (p < 0.0001), treatment (p < 0.0001). Multivariate analysis confirmed the independent impact on CSS of factors above mentioned, not including the diagnosis technique. Death risk was higher for patients diagnosed in 1996–2000 (HR: 1.32; 95% CI: 1.03; 1.68) and 2001–2005 (HR: 1.33; 95% CI: 1.05; 1.67) in comparison with 2006–2009 (reference group).ConclusionsThe current population-based report describes a major increase in HCC survival. Simultaneously an increased use of TACE has been detected, probable cofactor of the observed survival increase. Possibly additional efforts could be made to decrease the HCC stage at diagnosis through active surveillance of cirrhotic patients to allow an increase in curative treatments. For sure efforts should be made to comply with a standardised staging system for HCC, particularly for comparative population-based issues.  相似文献   

20.
The growth inhibition and induction of apoptosis brought by amygdalin and activated with β-d-glucosidase were tested for cytoactivity in HepG2 cells. The MTT viability assay showed that all samples had effects on HepG2 proliferation in dose and time response manners. IC50 of stand-alone amygdalin and activation with β-d-glucosidase on the proliferation of HepG2 cells for 48 h were 458.10 mg/mL and 3.2 mg/mL, respectively. Moreover, apoptotic cells were determined by AO/EB (acridine orange/ethidium bromide) fluorescent staining method and Annexin V-FITC/PI staining flow cytometry cell cycle analysis. With increasing of amygdalin concentration and the incubation time, the apoptotic rate was heightened. Compared with the control, there was significant difference (p < 0.01). Together, these findings indicate that amygdalin had no strong anti-HepG2 activity; however the ingredients of amygdalin activated with β-d-glucosidase had a higher and efficient anti-HepG2 activity. It was therefore suggested that this combination strategy may be applicable for treating tumors with a higher activity.  相似文献   

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