Síndrome metabólico, hígado graso no alcohólico y hepatocarcinoma / Metabolic syndrome, nonalcoholic fatty liver disease and hepatocellular carcinoma

En las últimas décadas, los cambios en el estilo de vida pro-vocaron un incremento en la prevalencia del síndrome meta-bólico y que la enfermedad por hígado graso no alcohólico (nonalcoholic fatty liver disease, NAFLD sus siglas en inglés) se convierta en la enfermedad hepática crónica más fre-cuente en todo el mundo. Los componentes del síndrome metabólico no son sólo altamente prevalentes en pacientes con hígado graso no alcohólico, sino que a la vez aumentan el riesgo de desarrollarlo. Esta relación bidireccional ha sido claramente establecida. Asimismo se considera que NAFLD podría ser el componente hepático del síndrome metabólico. Aunque NAFLD se considera principalmente una enfermedad benigna, puede progresar a fibrosis hepática grave y carcino-ma hepatocelular (CHC), incluso se encontraría este último en hígados no cirróticos. El objetivo de esta revisión es determinar los procesos fisio-patológicos comunes a estas entidades, cuáles son las estra-tegias diagnósticas recomendadas y cuáles las intervenciones terapéuticas actualmente aprobadas.

The Correlation between NK Cell and Liver Function in Patients with Primary Hepatocellular Carcinoma

BACKGROUND/AIMS: This study aimed to detect the expression of natural killer (NK) cell receptor natural killer group 2D (NKG2D) in the peripheral blood of patients with primary hepatocellular carcinoma and to discuss the correlation between NK cell cytotoxicity and liver function. METHODS: The number of NK cells and the expression of NK cell receptor NKG2D in peripheral blood were determined by flow cytometry in patients with primary hepatocellular carcinoma, hepatitis B cirrhosis, chronic hepatitis B, and healthy controls. RESULTS: When compared with patients in the healthy and the chronic hepatitis B groups, the primary hepatocellular carcinoma group showed significant decreases in all parameters, including the cytotoxicity of NK cells on K562 cells, expression rate of NKG2D in NK cells, number of NKG2D+ NK cells, expression level of NKG2D, and number of NK cells (p<0.05). The activity of NK cells showed a positive correlation, whereas the Child-Pugh scores in the primary hepatocellular carcinoma and the hepatitis B cirrhosis groups showed a negative correlation with all parameters detected above. CONCLUSIONS: The decrease of NK cell activity in patients with primary hepatocellular carcinoma is closely related to their lower expression of NKG2D. Liver function affects the expression of NKG2D and the activity of NK cells.

Aflatoxin M1 in the urine of non-carriers and chronic carriers of hepatitis B virus in Maringa, Brazil

Exposure to aflatoxins (AFs) in the diet may favour the development of hepatocellular carcinoma (HCC) and the acute exacerbation of hepatitis in chronic hepatitis B virus (HBV) carriers. Measurement of biomarkers such as aflatoxin M1 (AFM1), a metabolite of aflatoxin B1 (AFB1), in urine allows for the assessment of populations exposed to aflatoxins. The aim of this study was to investigate the occurrence of aflatoxin M1 in the urine of HBV carrier and non-carrier patients. One group included 43 randomly selected HBV carriers treated at two hospitals in the city of Maringa, Brazil, from March to June 2008. Control group consisted of 29 healthy adult volunteers with anti-HBs positive and HBsAg negative test results. Detection of AFM1 was performed by fluorescence using high performance liquid chromatography (HPLC) and post-column derivation with the Kobra Cell®. Of the 72 samples analysed, 05/29 (17.2%) AFM1 positive samples were from HBV non-carriers, and 16/43 (37.2%) of samples were from chronic HBV carriers. This study showed AFM1 in the urine of the two surveyed population. However, there is evidence that the chronic HBV carriers have a higher risk of developing HCC due to additive interaction between AFs and HBV.

A exposição às aflatoxinas (AFs) na dieta é um fator de risco para o desenvolvimento do carcinoma hepatocelular (CHC) e a exacerbação da hepatite aguda em indivíduos portadores do vírus da hepatite B (VHB). O uso de biomarcadores, como a aflatoxina M1 (AFM1) na urina, produto de biotransformação da aflatoxina B1 (AFB1), permite avaliar se a população está exposta às AFs. O objetivo do presente estudo foi investigar ocorrência de AFM1 na urina de portadores e não portadores crônicos do VHB. Foi selecionado um grupo, de forma aleatória, representado por 43 portadores do VHB atendidos em dois hospitais da cidade de Maringá, Brasil, no período de Março a Junho/2008. O grupo controle foi composto por 29 voluntários adultos saudáveis anti-HBs positivo e HBsAg negativo. A determinação de AFM1 foi realizada por meio de detecção por fluorescência em sistema de cromatografia a líquido de alta eficiência com derivação pós-coluna utilizando Kobra Cell®. Das 72 amostras analisadas, 05/29 (17,2%) foram positivas para AFM1 em indivíduos não portadores do VHB, e 16/43 (37,2%) de pacientes portadores do VHB. Este estudo demonstrou a ocorrência de AFM1 na urina dos dois grupos estudados. Entretanto, há evidências de que os portadores do VHB possuam alto risco no desenvolvimento do CHC devido ao efeito aditivo pela interação entre aflatoxinas e VHB.

The hypothesis of an effective strategy for resistance of hepatocellular carcinoma to therapy-autophagy / La hipótesis de una estrategia efectiva para la resistencia del carcinoma hepatocelular a la terapia autofágica

Hepatocellular carcinoma (HCC) is one of the most common malignant tumours and its five-year survival rate remains low. Autophagy is a catabolic process conserved among all eukaryotes ranging from yeast to mammals. Recently, many studies show that tumour cells can utilize autophagy as a cellular defence mechanism when facing metabolic stress. Thus, we hypothesize that autophagy may play an important role in the resistance of hepatocellular carcinomas to therapy. Although the exact role of autophagy on tumour cells is still complex and further studies are needed to prove the impact of autophagy on HCC, it suggests that autophagy may be a new therapeutic target for the resistance to therapy of HCC.

El carcinoma hepatocelular (CHC) es uno de los tumores malignos más comunes, y su tasa de super-vivencia a los cinco años sigue siendo baja. La autofagia es un proceso catabólico conservado en todos los eucariotas, que abarca desde las levaduras hasta los mamíferos. Recientemente, numerosos estudios han demostrado que las células tumorales pueden utilizar la autofagia como un mecanismo celular de defensa frente al estrés metabólico. De este modo, sostenemos la hipótesis de que la autofagia puede desempeñar un papel importante en la resistencia de los carcinomas hepatocelulares a la terapia. Aunque el papel exacto de la autofagia en las celulares tumorales sigue siendo complejo, y se requieren más estudios a fin de probar el impacto de la autofagia en el CHC, hay indicios de que la autofagia puede ser un nuevo objetivo terapéutico para la resistencia a la terapia del CHC.

Effects of aqueous saffron extract on nitric oxide production by two human carcinoma cell lines: hepatocellular carcinoma [HepG2] and laryngeal carcinoma [Hep2]

A number of studies have demonstrated the potential antitumor effects of saffron and its constituents on different malignant cells in vitro. It has been reported that a novel glycoconjugate isolated from corms and callus of saffron possesses cytotoxic activity against different tumor cellswith nitric oxide [NO] production. These data suggest that the cytotoxic effect of saffron extract may be related to an effect on nitric oxide production. The aim of the study was to investigate the effect of whole saffron extract on NO production by the hepatocellular carcinoma cell line [HepG-2] and laryngeal carcinoma cell line [Hep-2]. The cell lines were treated with a saffron extract. The morphologic changes were observed and recorded after 24, 48 and 72 of incubation. The MTT test was used to assess cell viability and the quantitative changes in NO production was evaluated using Griess test in the aforementioned time intervals. The morphologic images showed qualitative changes in both cell lines. The MTT assay results indicated that there was an increase in cytotoxic effect by adding the extract at concentrations of 0, 200, 400 and 800 micro g/ml. However, the NO concentration decreased significantly after 6, 12, 18, 24, 48 and 72 hours of incubation, respectively. IC[50] of 400 micro g/ml was obtained for HepG2 cells; however, Hep2 and L929 cells did not respond to any extract concentrations. This study suggested that the saffron extract had a cytotoxic effect on HepG-2 and Hep-2 cell lines. The cytotoxic effect was probably related to a decrease in the NO concentration

Expression of decoy receptor 3 in liver tissue microarrays.

Background. Decoy receptor 3 (DcR3), a new member of the tumour necrosis factor receptor (TNFR) superfamily, is amplified and overexpressed in various cancers. We investigated the expression of DcR3 protein in liver tissue microarrays and assessed its importance in patients with hepatocellular carcinoma (HCC). Methods. In this retrospective study, tissue from 120 patients with HCC, 48 with tissue at least 2 cm away from the tumour (juxta-tumour tissue), 62 with cirrhosis and 23 with normal livers were studied as tissue microarrays. Immunohistochemistry was used to detect the expression of DcR3. Statistical analyses were done to assess the association between DcR3 expression and the clinicopathological features of HCC. Results. The positivity rate of DcR3 in HCC tissue was significantly higher than that in juxta-tumour tissue, cirrhosis and normal liver (p=0.017, p<0.0001, p<0.0001, respectively). The positive rate of DcR3 in juxta-tumour and cirrhotic tissue both increased significantly when compared with normal liver tissue (p<0.0001, p=0.005, respectively). The positivity rate of DcR3 in HCC in clinical TNM stages I and II was significantly lower than that in stages III and IV (p<0.0001). The positivity rate of DcR3 in patients without metastasis within 20 months decreased significantly compared with those with metastasis (p<0.0001). DcR3 expression in patients with alphafoetoprotein levels >400 g/L, portal vein tumour emboli, capsular infiltration and multicentric tumour was significantly higher than in groups without these features (p=0.021, p<0.0001, p<0.0001, p=0.002, respectively). Conclusion. The overexpression of DcR3 might play an important role in the pathogenesis, progression and metastases of HCC. The DcR3 gene might serve as an important molecular biological indicator in diagnosing and predicting the biological behaviour of patients with HCC.

Serum levels of bcl-2 and cellular oxidative stress in patients with viral hepatitis.

PURPOSE: This study was conducted to investigate the presence of bcl-2 protein in the serum of patients with viral hepatitis and to find out if there is any correlation between bcl-2 protein levels and cellular oxidative stress in the pathogenesis of viral hepatitis. METHODS: This study was carried out on 130 patients with viral hepatitis, 70 with chronic hepatitis, 30 with liver cirrhosis and 30 with hepatocellular carcinoma (HCC) in addition to 20 healthy persons as the control. Serum bcl-2 protein was estimated by enzyme-linked immunosorbent assay, serum malondialdehyde (MDA), nitric oxide (NO) and antioxidant enzymes (GSH, GSH-px, GR and SOD) were measured using spectrophotometric analysis. RESULTS: bcl-2 protein level was significantly elevated in the serum of HCC, cirrhosis and chronic hepatitis groups as compared to control group. There were significant positive correlations between higher bcl-2 protein level and viral hepatitis markers (HBsAg, anti-HCV antibodies) in HCC and cirrhotic patients as compared to chronic hepatitis group. An increase in oxidative stress markers (MDA, NO) and a decrease in antioxidant enzyme activities (SOD, GSH and GSH-px) were observed. However, there was a negative correlation between bcl-2 levels and GR in all studied patient groups. CONCLUSIONS: The release of oxidative free radicals, deficiency in antioxidant enzymes and the expression of bcl-2 protein might play a role in the pathogenesis of viral hepatitis. The ability to measure bcl-2 protein in the serum could be useful as a prognostic marker of cancer patients.

Transcatheter Arterial Chemoembolization of Hepatocellular Carcinoma: Prevalence and Causative Factors of Extrahepatic Collateral Arteries in 479 Patients

OBJECTIVE: We wanted to investigate the prevalence and causative factors of extrahepatic arterial blood supply to hepatocellular carcinoma (HCC) at its initial presentation and during chemoembolization. MATERIALS AND METHODS: Between February 1998 and April 2000, consecutive 479 patients with newly diagnosed HCC were prospectively enrolled into this study. A total of 1629 sessions of transcatheter arterial chemoembolization (TACE) were performed in these patients (range: 1-15 sessions; mean: 3.4 sessions) until April 2004. For each TACE procedure, we determined the potential extrahepatic collateral arteries (ExCAs) depending on the location of the tumor, and we performed selective angiography of all suspected collaterals that could supply the tumor. The prevalence of ExCAs and the causative factors were analyzed. RESULTS: At initial presentation, 82 (17%) of these 479 patients showed 108 ExCAs supplying tumors. Univariate analysis showed that tumor size (p or = 5 cm) was significantly higher than that for those patients with a small tumor (< 5 cm) (p < 0.01). CONCLUSION: The presence of ExCAs supplying HCC is rather common, and the tumor size is a significant causative factor for the development of these collateral arteries.

Three-dimensional conformal radiation therapy and periodic irradiation with the deep insipration breath-hold technique for hepatocellular carcinoma.

Nine cases of primary hepatocellular carcinoma were treated with 3D-conformal radiation therapy using computerized planning system. This technique permits the precise delivery of a high dose of radiation to the target while sparing most of the normal liver tissue. In order to decrease the effect of organ movement related to respiration, periodical irradiation was combined with the deep inspiration breath-hold technique. The radiation dose was equivalent to conventional radiation with a total dose of 50-70 Gy with 2 Gy, 5 times a week. Irradiation was given in 1-10 fractions which encompassed the target with 90 per cent isodose line. The patients tolerated the treatment procedure well without any complications inherent to the technique. The tumors were decreased in size, the pain symptom and abdominal discomfort were relieved for 3-20 months. This technique is an effective and safe treatment for palliation in hepatocellular carcinoma especially in locally advanced stages with large or multiple lesions. However, long term follow-up should be done to evaluate the late radiation effect and clinical outcome.

Mecanismos de oncogénesis viral / Mechanisms of viral oncogenesis

Actualmente se sabe que el 20 por ciento de los cánceres humanos están asociados con virus oncogénicos. El virus papiloma humano con cáncer anogenital, los virus de la hepatitis B y C con carcinoma hepatocelular, el virus Epstein Barr con carcinomas nasofaríngeos y linfomas, el virus de la leucemia-linfoma T con leucemias en el adulto. Un rasgo común en todos los tumores asociados con infección viral es el largo período de latencia entre la infección y la aparición de la neoplasia y la baja proporción de individuos infectados que desarrollan un tumor maligno. Estas observaciones indican que los virus oncogénicos son necesarios pero no suficientes para inducir cáncer, otros factores podrían estar involucrados. Esta actualización resume informaciones recientes acerca de los mecanismos de carcinogénesis viral, en particular, la interacción de oncoproteínas virales y proteínas supresoras tumorales. La inactivación de estas proteínas supresoras podría representar una estrategia común a través de la cual los virus tumorales pueden contribuir a la transformación maligna de la célula

Natural killer [NK] cell activity in hepatocellular carcinoma [HCC] liver cirrhosis [LC] and schistosomiasis

Hepatocellular carcinoma [BCC] represents a major health problem in many developing countries in Asia and africa including Egypt. The role of the immune system especially natural killer [NK] cells had been poorly investigated in this disease. Our study included 67 patients [thirty seven patients with HCC, 25 with liver cirrhosis [LC] both secondary to alcoholic liver disease [ALD] and chronic viral hepatitis [CVH], and 15 patients with intestinal schistosomiasis]. The results were compared with age-and sex-matched healthy controls. Peripheral blood lymphocytes [PBL] were isolated from heparinized blood and NK cell activity was studied by the standard 4-hr Cr51 release assay using erythroleukemia cell line [K562] Results of this study revealed marked suppression of NK cell activity in HCC patients compared to that of the controls. The percent NK cytotoxicity at E: T ratio 100: 1 was 41.4 +/- 21.9 in patients and 67.9 +/- 7.7 in controls. The suppression of NK activity was stage-dependent, being more evident in advanced than earlier stages of the disease. LC patients showed lower NK activity than controls. However, there was no suppression in schistosomiasis patients. We conclude that suppression of NK cyotoxicity in LC might predispose to the development of HCC in these patients, however, with progression of cancer, the degree of suppression increases markedly leading to immune system breakdown

Inhibitory effect of hepatocellular carcinoma [HCC] sera on natural killer [NK] cell activity

The role of inhibitory factors [IFs] in the sera of cancer patients as a responsible factor for natural killer [NK] suppression was demonstrated in some types of cancer. In this study, we tried to investigate the presence of IF [s] in the sera of HCC patients. NK. cells were isolated from normal healthy donors and these cells were incubated with sera from 37 BCC patients at different stages of the disease as well as with sera from normal healthy controls of matched age and sex. After 4hr incubation, NK. activity was measured by standard Cr51 release assay. The levels of IgG, IgM and IgA immune complexes in sera of patients and controls were measured by ELISA technique. Results showed significant suppression of. NK. cell activity after incubation with BCC sera compared to control sera. The degree of depression of NK. activity was concentration dependent; there was slight suppression at 5% serum concentration and it was maximized at 25-50%. Levels of immune complexes were significantly higher in patients than controls except IgM-IC. We conclude that there is some IF [s] in the sera of HCC patients which may contribute to depression of NK activity in these patients. One of these factors might be tumor antigen-antibody complexes

Combined use of tamoxifen, cyclosporin A, and verapamil for modulating multidrug resistance in human hepatocellular carcinoma cell lines

The intensive use of chemotherapeutic agents for the treatment of cancer has resulted in the cure or improved survival of many patients. But unfortunately, many cancers including human hepatocellular carcinoma (HCC) don't respond to chemotherapy. One of the major mechanisms for the drug resistance in the HCC is an elevated MDR1 RNA expression which makes cells become multidrug resistant. To overcome the multidrug resistance (MDR) phenotype, a high dose of verapamil is required both clinically and experimentally. Accordingly we have examined the MDR modulating effects with combinations of tamoxifen, cyclosporin A, and verapamil in vitro with the physiologically achievable concentrations of each agent, i.e., 2.0 microM/L for tamoxifen, 1.6 microM/L for cyclosporin A, and 2.5 microM/L for verapamil respectively in HCC lines. As expected, verapamil alone with the physiologically achievable concentration at which we tested didn't enhance the doxorubicin cytotoxicity in the HCC lines. Furthermore, any verapamil combination with cyclosporin A or tamoxifen was not effective in overcoming the doxorubicin resistance in the high MDR1 expressor (Hep-G2) line. However tamoxifen reduced the IC50 of doxorubicin by a factor of 1.9 in the low MDR1 expressor (SK-Hep1) and 1.1 in the high MDR1 expressor line (p< 10(-5) respectively). Of interest, combinations of tamoxifen and cyclosporin A showed a significant reduction in the IC50 of doxorubicin in both HCC lines. The IC50 of doxorubicin was reduced by a factor of 3.9 and 1.3, i.e., from 0.023943 micrograms/ml to 0.006157 micrograms/ml (p< 10(-5)) in the SK-Hep1 cell line, and 0.068819 micrograms/ml to 0.052442 micrograms/ml (p< 10(-5)) in Hep-G2 respectively when tamoxifen and cyclosporin A were administered together. Both the estrogen and progesterone receptors in the SK-Hep1 and Hep-G2 lines were less than 0.01 fmol/mg of cytosol protein, respectively. It is therefore suggested that the reversal of doxorubicin resistance is unrelated to their anti-estrogenic activity in the HCC lines. Three modulator combinations of tamoxifen, cyclosporin A, and verapamil were not more effective than the combination of tamoxifen and cyclosporin A on the sensitivity to doxorubicin. MDR modulators of tamoxifen, cyclosporin A, and verapamil didn't reduce the IC50 of cisplatin to the clinically achievable concentration range in HCC lines. In summary, the combination of tamoxifen and cyclosporin A at the concentrations normally seen after clinical administration of these modulators showed significant synergism on the sensitivity to doxorubicin in both low and high MDR1 expressor HCC lines. These data indicate the need for in vivo trials.

Virus de la hepatitis C y hepatocarcinoma

Se peresenta el caso de un paciente de sexo masculino de 56 años de edad con antecedentes de hemofilia B, que recibió suplencia de factor IX para un procedimiento quirúrgico y diez años más tarde se encuentra con cuadro de hepatitis crónica por virus C, cirrosis secundaria asociada a una masa hepática compatible con hepatocarcinoma comprobada por ultrasonografía, tomografía axial computarizada,arteriografía hepática, y por los valores anormalmente altos de alfafetoproteina. El virus de la hepatitis C recientemente identificado, es responsable de al menos 85 por ciento de la llamadas hepatits No-A-No-B y puede ser factor desencadenante de cirrosis y hepatocarcinoma, por lo cual es indispensable su identificación y prevención adecuadas.