Lentivirus mediated silencing of Ubiquitin Specific Peptidase 39 inhibits cell proliferation of human hepatocellular carcinoma cells in vitro

BACKGROUND: Ubiquitin Specific Peptidase 39 (USP39) is a 65 kDa SR-related protein involved in RNA splicing. Previous studies showed that USP39 is related with tumorigenesis of human breast cancer cells. RESULTS: In the present study, we investigated the functions of USP39 in human hepatocellular carcinoma (HCC) cell line SMMC-7721. We knocked down the expression of USP39 through lentivirus mediated RNA interference. The results of qRT-PCR and western blotting assay showed that both the mRNA and protein levels were suppressed efficiently after USP39 specific shRNA was delivered into SMMC-7721 cells. Cell growth was significantly inhibited as determined by MTT assay. Crystal violet staining indicated that colony numbers and sizes were both reduced after knock-down of USP39. Furthermore, suppression of USP39 arrested cell cycle progression at G2/M phase in SMMC-7721cells. In addition, Annexin V showed that downregulation of USP39 significantly increased the population of apoptotic cells. CONCLUSIONS: All our results suggest that USP39 is important for HCC cell proliferation and is a potential target for molecular therapy of HCC.

Computerized Tomography Contrast Induced Nephropathy (CIN) among adult inpatients / Nefropatia induzida por contraste (NIC) em pacientes adultos internados submetidos à tomografia computadorizada por contraste

Introduction: Contrast induced nephropathy (CIN) is one of the complications of the use of intravascular contrast agents, being defined as a reduction of the glomerular filtration rate caused by the iodinated contrast. Most CIN data derive from the cardiovascular literature, which identified as the most consistent risk factors pre-existing chronic renal insufficiency and diabetes mellitus. However, these studies limit their conclusions to a more specific patient population. Computerized tomography as a cause of CIN has been studied less often. Objective: To report on the incidence of computerized tomography contrast induced nephropathy (CIN) in an inpatient population of a tertiary general hospital, identifying potentially avoidable risk factors. Methods: We performed a prospective cohort study with inpatients admitted at a tertiary hospital requiring contrast-induced CT. The primary outcome was the development of CIN, measure by the alteration of serum creatinine or glomerular filtration rate in 48 or 72 hours. Through clinical interview, we verified possible risk factors and preventive measures instituted by the medical team and their association with development of CIN. Results: Of a total of 410 patients, 35 (8.5%) developed CIN. There was a positive correlation between CIN and the presence of diabetes mellitus (OR = 2.15; 95%CI 1.35-4.06; p = 0.02), heart failure (OR = 2.23; 95%CI 1.18-8.8; p = 0.022), and renal failure (OR = 3.36; 95%CI 1.57- 7.17; p = 0.002) Conclusion: Incidence of CIN varies according to the population. Diabetes mellitus, heart failure and renal failure were independent risk factors for the development of CT-associated CIN. Further studies are needed to better understand and treat CT-associated CIN. .

Introdução: Nefropatia induzida por contraste (NIC) é consequência do uso de meios de contraste intravenoso, sendo definida como uma redução da taxa de filtração glomerular. A maioria dos dados de NIC são da literatura cardiovascular, que identificou como fatores de risco insuficiência renal crônica e diabetes. Entretanto, esses estudos limitam suas conclusões a uma população especifica de pacientes. Tomografia Computadorizada contrastada como causa de NIC foi menos estudada. Objetivo: Reportar incidência de NIC numa população de pacientes internados em hospital terciário submetidos à tomografia computadorizada com contraste, identificando possíveis fatores de risco evitáveis. Métodos: Realizamos um estudo de coorte prospectivo com pacientes internados em hospital terciário e que necessitaram de tomografia computadorizada com contraste. O desfecho primário foi desenvolvimento de NIC, verificado por meio da variação da creatinina sérica ou taxa de filtração glomerular em 48 ou 72 horas. Em entrevista clínica, verificamos possíveis fatores de risco, assim como medidas preventivas instituídas pela equipe médica e suas possíveis associações com desenvolvimento de NIC. Resultados: Do total de 410 pacientes, 35 (8,5%) desenvolveram NIC. Houve correlação positiva entre desenvolvimento de NIC e a presença de diabetes mellitus (OR = 2,15; 95%CI 1,35-4,06; p = 0,02), insuficiência cardíaca (OR = 2,23; 95%CI 1,18-8,8; p = 0,022), e insuficiência renal (OR = 3,36; 95%CI 1,57-7,17; p = 0,002). Conclusão: A incidência de NIC varia de acordo com a população. Diabetes, insuficiência cardíaca e insuficiência renal foram fatores de risco independentes para o desenvolvimento de NIC. Mais estudos são ...

A socialização da medicina na era do adhemarismo / The socialization of medicine in the era of São Paulo Governor Adhemar de Barros

A análise observa as conexões entre o processo de profissionalização dos médicos paulistas e políticas de saúde do governo estadual de Adhemar de Barros em São Paulo (1947-1951), em meio a amplas mudanças na área de saúde denominadas pelos médicos paulistas “socialização da medicina”. Reconhecemos aspectos ambivalentes para o profissionalismo médico diante desse governo populista, como: a luta médica pela equiparação ante os advogados servidores públicos estaduais; a criação de uma secretaria de saúde estadual; e certos elos contraditórios entre a área de saúde adhemarista e a ideologia e a organização profissionais da medicina paulista. Nesse particular, o artigo aprofunda a análise de manifestações ideológicas de importantes lideranças médicas paulistas.

The article analyzes how the process of the professionalization of physicians in São Paulo related to healthcare policy under the administration of São Paulo governor Adhemar de Barros (1947-1951) during a period of broad change in the realm of health known by São Paulo physicians as the “socialization of medicine.” Medical professionalism confronted certain ambivalences under this populist administration, including doctors’ struggle to achieve pay equal to that of state public attorneys; the establishment of a state health department; and some contradictory ties between the area of health under Adhemar and the professional ideology and organization of medicine in São Paulo. The article undertakes a more in-depth analysis of the ideological manifestations of important leaders in the state’s medical community.

Role of complementary therapies in the understanding of primary healthcare professionals: a systematic review / Papel de prácticas complementarias en la comprensión de los profesionales de atención primaria: una revisión sistemática / Papel das práticas complementares na compreensão dos profissionais da Atenção Básica: uma revisão sistemática

Objective To identify the understanding of the healthcare professionals in relation to the role of complementary therapies in primary health care. Method Systematic review by way of the following information sources: PubMed, CINAHL, PeriEnf, AMED, EMBASE, Web of Science, Psicoinfo and Psicodoc, using the keyword Primary Health Care alone, and associated with the following keywords: Medicinal Plants, Herbal Medicine, Homeopathy, Traditional Chinese Medicine, Acupuncture, Anthroposophical Medicine. Results Twenty-two studies from 1986 to 2011 were included. We identified three styles of practice: conventional medicine, complementary therapies and integrative medicine. Positioning professional practices within these three styles may facilitate discussion of concepts of health care, enhancing the health care provided as a result. Conclusion The work process in primary care presents difficulties for conducting integrative and holistic health care, but this practice has been introduced over time by professionals who integrate conventional medicine and complementary therapies, concerned with the care and well-being of patients.
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Objetivo Identificar la comprensión de los profesionales sobre el papel de las prácticas complementarias en la atención primaria. Método Revisión sistemática. Fuentes de datos: PubMed, CINAHL, PeriEnf, AMED, EMBASE, Web of Science, Psicodoc y PysicoInfo. Descriptor Atención Primaria se asoció solo a los siguientes descriptores: plantas medicinales, fitoterapia, homeopatía, acupuntura, medicina tradicional china, medicina antroposófica. Resultados Se incluyeron 22 pesquisas entre 1986-2011. Tres estilos de práctica se identificaron: medicina convencional, medicina integrativa y Terapias Complementarias. Identificar la práctica profesional dentro de estos tres estilos puede facilitar la discusión de los conceptos de salud y la atención, mejorar la atención. Conclusión El proceso de trabajo en atención primaria presenta dificultades para realización de integración y atención integral, pero esta práctica se ha introducido con profesionales que integran medicina convencional y complementaria, ocupados con la atención y bienestar del paciente.


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Objetivo Identificar a compreensão dos profissionais de saúde quanto ao papel das práticas complementares na Atenção Básica. Método Revisão sistemática cujas fontes de informação foram: PubMed, CINAHL, PeriEnf, AMED, EMBASE, Web of Science, PysicoInfo e PsicoDoc, utilizando o descritor Atenção Básica associado, isoladamente, aos seguintes descritores: Plantas Medicinais, Fitoterapia, Homeopatia, Medicina Tradicional Chinesa, Acupuntura, Medicina Antroposófica. Resultados Incluíram-se 22 estudos entre 1986-2011. Identificaram-se três estilos de prática: medicina convencional, práticas integrativas e medicina integrativa. Posicionar a prática profissional dentro desses três estilos pode facilitar a discussão de concepções de saúde e cuidado, ampliando o cuidado. Conclusão O processo de trabalho na Atenção Básica apresenta dificuldades para a realização de cuidado integrativo e holístico, mas essa prática vem sendo introduzida com profissionais que integram medicina convencional e práticas complementares, preocupados com o cuidado e o bem-estar do paciente.

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Newer treatments for advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. The only curative treatment modalities for HCC are surgery, percutaneous ablation, and liver transplantation. Unfortunately, the majority of patients have unresectable disease at diagnosis. Therefore, effective treatment options are needed for patients with advanced HCC. The current standard treatment for patients with advanced HCC, according to the Barcelona Clinic Liver Cancer staging system, is the multikinase inhibitor sorafenib. Other alternative therapies are required, due to the limited treatment response to, and tolerance of, this molecular target agent. Clinical trials of hepatic artery infusion chemotherapy, radioembolization, and multimodal treatments have shown favorable results in advanced HCC patients. This article introduces new treatment modalities for advanced HCC and discusses future therapeutic possibilities.

A novel prognostic factor for hepatocellular carcinoma: protein disulfide isomerase

BACKGROUND/AIMS: Protein disulfide isomerase (PDI) has been implicated in the survival and progression of some cancer cells, by compensating for endoplasmic reticulum stress by upregulating the protein-folding capacity. However, its prognostic role in patients with hepatocellular carcinoma (HCC) has not been investigated. METHODS: We collected HCC tissues from 83 HCC patients who underwent surgical resection for an immunohistochemical study of PDI. Overall survival (OS) was measured from the date of surgical resection until the date of death from any cause. Radiological progression was evaluated using the modified Response Evaluation Criteria in Solid Tumors in an independent radiological assessment. RESULTS: PDI expression was found to be increased in human HCC compared to adjacent nontumor tissues. Increased immunopositivity for PDI was associated with a high Edmondson-Steiner grade (p = 0.028). Univariate analysis of patients who had undergone surgical resection for HCC showed that tumor PDI upregulation is a significant risk factor for poor OS (p = 0.016; hazard ratio [HR], 1.980) and time to progression (TTP; p = 0.007; HR, 1.971). Multivariate analyses revealed that high PDI expression was an independent predictor of a shorter TTP (p = 0.015; HR, 1.865) and poor OS (p = 0.012; HR, 2.069). CONCLUSIONS: Upregulated PDI expression is associated with aggressive clinicopathological features of HCC; thus, PDI might serve as an independent prognostic factor and a potential therapeutic target for HCC patients.

Pro-oncogenic potential of NM23-H2 in hepatocellular carcinoma

NM23 is a family of structurally and functionally conserved proteins known as nucleoside diphosphate kinases (NDPK). There is abundant mRNA expression of NM23-H1, NM23-H2, or a read through transcript (NM23-LV) in the primary sites of hepatocellular carcinoma (HCC). Although the NM23-H1 protein is implicated as a metastasis suppressor, the role of NM23-H2 appears to be less understood. Thus, the aim of this study was to examine whether NM23-H2 is associated with hepatocarcinogenesis. The level of NM23-H2 expression in tumor tissues and the surrounding matrix appeared to be independent of etiology and tumor differentiation. Its subcellular localization was confined to mainly the cytoplasm and to a lesser extent in the nucleus. Ectopic expression of NM23-H2 in NIH3T3 fibroblasts and HLK3 hepatocytes showed a transformed morphology, enhanced focus formation, and allowed anchorage-independent growth. Finally, NIH3T3 fibroblasts and HLK3 hepatocytes stably expressing NM23-H2 produced tumors in athymic mice and showed c-Myc over-expression. In addition, NF-kappaB and cyclin D1 expression were also increased by NM23-H2. Lentiviral delivery of NM23-H2 shRNA inhibited tumor growth of xenotransplanted tumors produced from HLK3 cells stably expressing NM23-H2. Collectively, these results indicate that NM23-H2 may be pro-oncogenic in hepatocarcinogenesis.

Effects of Benzo(a)pyrene on the Expression of Heat Shock Proteins, Pro-inflammatory Cytokines and Antioxidant Enzymes in Hepatic Tumors Induced by Rat Hepatoma N1-S1 Cells

Benzo(a)pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) that is easily introduced to humans via consumption of grilled or smoked meat. BaP causes harmful oxidative effects on cell development, growth and survival through an increase in membrane lipid peroxidation, oxidative DNA damage and mutagenesis. Therefore, the present study was conducted to evaluate the synergistic effects of BaP on oxidative stress in hepatic tumors. In this study, we established a hepatic tumor model by injecting rat hepatoma N1-S1 cells into healthy rats. Changes in the abundance of heat shock proteins (HSPs), antioxidant enzymes and pro-inflammatory cytokines were then investigated by western blot analysis. In addition, we examined changes in oxidative stress levels. Injection of N1-S1 cells or concomitant injection of BaP and N1-S1 cells resulted in the formation of hepatic tumors at the injection site. Evaluation of rat plasma reveals that hepatic tumors induced by BaP and N1-S1 cells expresses higher levels of Hsp27, superoxide dismutase (SOD), and tumor necrosis factor-alpha (TNF-alpha) when compared to those induced by N1-S1 cells only. The collective results of this study suggest that BaP exerts synergistic effects on the expression of HSP, cytokines and antioxidant enzymes in hepatic tumors induced by rat hepatoma N1-S1 cells.

IQGAP1 is overexpressed in hepatocellular carcinoma and promotes cell proliferation by Akt activation

The scaffold protein IQGAP1 shows elevated levels in several cancer types, but its expression in hepatocellular carcinoma is unknown. We found that 58% of human hepatocellular carcinoma tissue samples had increased IQGAP1 expression compared to adjacent normal tissue. Overexpressing IQGAP1 raised the in vivo tumorigenicity of hepatocellular carcinoma cells, and forced overexpression of IQGAP1 in vitro stimulated cell proliferation. Cell growth was reduced by knockdown or mutation of IQGAP1, or by treatment of cells with a phosphotidylinositol 3-kinase inhibitor. To determine the mechanism by which IQGAP1 overexpression affected hepatocellular carcinoma cells, we confirmed its interaction in these cells with mammalian target of rapamycin (mTOR), a serine/threonine kinase that integrates signals about nutrient and energy status with downstream effectors that influence cell division. In addition, we discovered a new interaction involving IQGAP1, mTOR and Akt, which is a downstream target of mTOR. Akt phosphorylation on Ser-473, which is catalyzed by mTOR and required for Akt activation, increased with increasing amounts of IQGAP1, and decreased with IQGAP1 mutation. We hypothesize that IQGAP1 is a scaffold that facilitates mTOR and Akt interaction.

Lack of influence of cyclooxygenese-2 expression in hepatocellular carcinomas on patient survival.

Recent studies suggest that cyclooxygenese-2 (COX-2) enzyme activation may play a role in hepatocarcinogenesis. However, the clinical significance of COX-2 expression in hepatocellular carcinoma (HCC) remains obscure. This study evaluated COX-2 expression in hepatitis B and hepatitis C virus related HCC and in HCC patients with an unknown etiology. Liver tissue samples of 31 patients with HCC (27 men and 4 women; age range, 48-75 years) were analyzed. COX-2 expression was evaluated by immunohistochemically in the tumor tissues. Patient data including age, sex, Child score, stage, grade of the tumor and survival were analyzed. Of these patients 19 were positive for hepatitis B virus (HBV), 6 were positive for hepatitis C virus (HCV) and 6 patients were negative for all viral markers and other etiologic factors. COX-2 staining were evaluated in 2 groups (group 1: COX-2 expression less than 25% (grades 1-2 COX-2 expression), and group 2: Cox-2 expression 25% or more (grades 3-5 COX-2 expression). COX-2 expression was shown in all HCC samples with positive or negative viral markers. No difference was found between degree of COX-2 expression and the etiology of HCC. COX-2 expression was not correlated with number of lesion or stage of the disease or grade of the tumor. COX-2 expression was not related with Child score of the patients. Median survival of all patients was 32 months. Median survival of patients did not differ according to patient's viral marker status. No difference was observed in median survival of patients in group 1 and 2. As a result, COX-2 system seem to be shared part in hepatocarcinogenesis regardless factors that initiate the disease. Although COX-2 expression appears to be independent of disease's characteristics', treatments that target this system appear to be feasible in the management of HCC.

Down-regulation of survivin in growth inhibition of hepatoma cells induced by a selective cyclooxygenase-2 inhibitor / 대한간학회지

BACKGROUND/AIMS: Cyclooxygenase-2 (COX-2) inhibitors reportedly inhibit the growth of hepatocellular carcinoma (HCC) via caspase-dependent or caspase-independent apoptosis, which is due to COX-2 being associated with hepatocarcinogenesis. Survivin is highly expressed in most human cancers, but the mechanism regulating survivin expression remains unclear. We investigated the regulatory expression of survivin in selective-COX-2-inhibitor-induced growth inhibition of hepatoma cells. METHODS: After treatment with NS-398 (a selective COX-2 inhibitor) at various concentrations (10, 50, 100, 150, and 200 micrometer), the growth inhibition of Hep3B hepatoma cells was assessed by an MTT cell-viability assay, DNA fragmentation gel analysis, and flow cytometry. The expression of survivin transcript was analyzed by reverse-transcription polymerase chain reactions. RESULTS: NS-398 inhibited the growth of hepatoma cells by an amount dependent on the concentration and the time since treatment. Apoptotic DNA ladder and flow-cytometry shifting to the sub-G1 phase were revealed in NS-398-induced growth inhibition of hepatoma cells. NS-398 suppressed the expression of the survivin gene in a concentration- and time-dependent manner. CONCLUSIONS: Survivin was down-regulated in the growth inhibition of hepatoma cells induced by a selective COX-2 inhibitor, NS-398, in a concentration- and time-dependent manner. These results suggest the therapeutic inhibition of COX-2 via suppression of survivin in HCC.

Anti-tumor mechanisms and regulation of survivin by selective cyclooxygenase-2 inhibitor / 대한간학회지

No abstract available.

Regulation of cell growth by fatty acid-CoA ligase 4 in human hepatocellular carcinoma cells

Fatty acid-CoA ligase 4 (FACL4) is a central enzyme controlling the unesterified free arachidonic acid (AA) level in cells and the free AA is known to induce apoptosis. We have recently reported that expression of FACL4 is upregulated in about 40% of human hepatocellular carcinoma (HCC) and 50% of HCC cell lines, suggesting that FACL4 may be involved in liver carcinogenesis. In this study, we investigated whether HCC cell growth is regulated by FACL4. Immunoblot analysis showed that SNU 398 cells express very low or no detectable level of FACL4. We, therefore, transfected the SNU 398 cells with FACL4 expression vector, and clones expressing FACL4 were pooled and analyzed. We found that forced expression of FACL4 in SNU 398 promotes the growth of cells. In addition, we observed that triacsin C, a FACL4 inhibitor, inhibits the growth of Hep 3B cell line which expresses high level of endogenous FACL4. We also found that the triacsin C-mediated growth inhibition in Hep 3B cells results from the induction of apoptosis with evidence of Bcl-2 reduction. Altogether, our data show that FACL4 affects HCC cell growth and suggest that modulation of FACL4 expression/activity is an approach for treatment of HCC.

Chemomodulatory action of Brassica compestris (var sarason) on hepatic carcinogen metabolizing enzymes, antioxidant profiles and lipid peroxidation.

The effect of two different doses (400 and 800 mg/kg body wt/day for 15 days) of a 95% ethanolic extract of the seeds of Brassica compestris (var sarason) was examined on carcinogen metabolizing phase-I and phase-II enzymes,antioxidant enzymes and glutathione content and lipid peroxidation in the liver of Swiss albino mice. Positive control mice were treated with butylated hydroxyanisole (BHA). Significant elevation in the levels of cytochrome p450 (p<0,.05), cytochrome b5 (p < 0.05) glutathione s-transferase (p<0.01), DT-diaphorase (p<0.05), superoxide dismutase (p<0.01), catalase (p < 0.001) and reduced glutathione (p<0.001) was noted in the group treated with 800 mg/kg body wt. of Brassica extract in comparison with the negative control group. Brassica compestris acted as a bifunctional inducer since it induced both phase - I and phase - H enzyme systems. Since phase-I and phase-II enzymes are considered to be reliable markers for evaluating the chemoprevention efficacy of particular test materials,these findings are suggestive of potential chemopreventive roles for Brassica seed extract.

Chemomodulatory effect of Moringa oleifera, Lam, on hepatic carcinogen metabolising enzymes, antioxidant parameters and skin papillomagenesis in mice.

The modulatory effects of a hydro-alcoholic extract of drumsticks of Moringa oliefera Lam at doses of 125 mg/kg bodyweight and 250 mg/ kg body weight for 7 and 14 days, respectively, were investigated with reference to drug metabolising Phase I (Cytochrome b(5) and Cytochrome p(450) ) and Phase II (Glutathione-S- transferase) enzymes, anti-oxidant enzymes, glutathione content and lipid peroxidation in the liver of 6-8 week old female Swiss albino mice. Further, the chemopreventive efficacy of the extract was evaluated in a two stage model of 7,12 - dimethylbenz(a)anthracene induced skin papillomagenesis. Significant increase (p<0.05 to p<0.01) in the activities of hepatic cytochrome b(5), cytochrome p(450), catalase, glutathione peroxidase ( GPx ), glutathione reductase (GR), acid soluble sulfhydryl content (-SH ) and a significant decrease ( p<0.01 ) in the hepatic MDA level were observed at both dose levels of treatment when compared with the control values. Glutathione-S- transferase ( GST )activity was found to be significantly increased (p<0.01 ) only at the higher dose level. Butylated hydroxyanisol (BHA ) fed at a dose of 0.75% in the diet for 7 and 14 days (positive control ) caused a significant increase (p<0.05 to p<0.01) in the levels of hepatic phase I and phase II enzymes, anti- oxidant enzymes, glutathione content and a decrease in lipid peroxidation. The skin papillomagenesis studies demonstrated a significant decrease (p<0.05 ) in the percentage of mice with papillomas, average number of papillomas per mouse and papillomas per papilloma bearing mouse when the animals received a topical application of the extract at a dose of 5mg/ kg body weight in the peri-initiation phase 7 days before and 7 days after DMBA application, Group II ), promotional phase (from the day of croton oil application and continued till the end of the experiment, Group III ) and both peri and post initiation stages (from 7 days prior to DMBA application and continued till the end of the experiment, Group IV) compared to the control group (Group I ). The percentage inhibition of tumor multiplicity has been recorded to be 27, 72, and 81 in Groups II, III, and IV, respectively. These findings are suggestive of a possible chemopreventive potential of Moringa oliefera drumstick extract against chemical carcinogenesis.

Sox-4 is a positive regulator of Hep3B and HepG2 cells' apoptosis induced by prostaglandin (PG)A2 and 12-PGJ2

We reported earlier that expression of Sox-4 was found to be elevated during prostaglandin (PG) A2 and delta(12)-PGJ(12) induced apoptosis in human hepatocarcinoma Hep3B cells. In this study, the role of Sox-4 was examined using human Hep3B and HepG2 cell lines. Sox-4 induction by several apoptotic inducer such as A23187 (Ca(2+) ionophore) and etoposide (topoisomerase II inhibitor) and Sox-4 transfection into the cells were able to induce apoptosis as observed by the cellular DNA fragmentation. Antisense oligonucleotide of Sox-4 inhibited the induction of Sox-4 expression and blocked the formation of DNA fragmentation by PGA(2) and delta(12)-PGJ(12) in Hep3B and HepG2 cells. Sox-4-induced apoptosis was accompanied with caspase-1 activation indicating that caspase cascade was involved in this apoptotic pathway. These results indicate that Sox-4 is involved in Hep3B and HepG2 cells apoptosis as an important apoptotic mediator.

Telomerase is strongly activated in hepatocellular carcinoma but not in chronic hepatitis and cirrhosis

Telomerase is highly activated in human immortal cell lines and tumor tissues, whereas it is not activated in primary cell strains and many tumor-adjacent tissues. It is suggested that telomerase activation is one of the critical steps in malignant transformation. In the present study, the telomerase activity was investigated in hepatocellular carcinoma tissues and non-tumor liver tissues from Korean patients with chronic hepatitis and cirrhosis. Eighty two liver tissues (24 chronic hepatitis specimens, 34 cirrhosis specimens, and 24 hepatocellular carcinomas) were obtained from 23 chronic viral hepatitis patients, 19 cirrhosis patients (including 7 liver transplants), and 24 patients with hepatocellular carcinoma, of which the surrounding non-tumor liver tissues were available in 16 patients (1 chronic hepatitis and 15 cirrhosis). As negative controls, 3 normal liver tissues were included. Protein from liver specimens was purified by a detergent lysis method as described elsewhere, and telomerase activity was measured in 2 diluents of each sample (1:1 and 1:100) by a telomeric repeat amplification protocol (TRAP). Telomerase was strongly activated in 79% (19/24) of the hepatocellular carcinomas, while weakly in 8% (2/24) of the chronic hepatitis tissues and in 24% (8/34) of the cirrhosis tissues. All of 3 normal control livers showed no telomerase activation. No relationship could be observed between the enhancement of telomerase activity and tumor nature. None of the chronic heaptitis or cirrhosis patients with mild telomerase activation in the liver have developed hepatocellular carcinoma for at least 2 years of follow-up period. These results suggest that the strong enhancement of telomerase activity may be a critical part of hepatocarcinogenesis, although the exact mechanism of such high activation in hepatocellular carcinoma is not clear. In addition, further study will be necessary to clarify the reason why no telomerase activity detectable by a conventional TRAP can be seen in some hepatocellular carcinoma.

Efeito das vastatinas sobre a hidrólise hepática do colesterol esterificado, em células de hepatoblastoma humano HEP G2 / Effects of vastatins in the hepatic hidrolase of esterified cholesterol in human HEP G2 hepatoblastoma cells

O presente trabalho se valeu de células de hepatoma humano Hep G2 para estudar se existe algum efeito das vastatinas sobre a atividade das enzimas que governam a hidrólise hepática do coleterol: colesterol éster hidrolases lisossomal, citosólica e microssomal. As enzimas foram incubadas com ou sem amostras de vastatina, dissovidas em dimetilsulfóxido. A adiçao das vastatinas ofereceu distintos resultados, conforme a maneira que se apresentou o substrato às enzimas. No caso da colesterol éster hidrolase lisossomal, obteve-se inibiçao em substrato Hajjar, com sais biliares, e estimulaçao em substrato Brecher, desprovido de sais biliares. A hidrolase citosólica teve sua atividade inibida em substrato Hajjar e constante em substrato Brecher.

Serum leucine aminopeptidase profile in cancers of gastro-intestinal tract with special reference to hepatic metastasis.

Serum leucine aminopeptidase (LAP) was estimated in 30 cases of gastro-intestinal cancers, and compared with 50 age and sex matched controls. Highly significant increase of serum LAP was seen in 7 patients with hepatic metastasis (p less than 0.001) from adenocarcinoma of stomach, colon and rectum. The enzyme values showed a highly significant increase in carcinoma of colon, when compared with different anatomical sites of the gastro-intestinal tract (p less than 0.001). However, in adenocarcinoma of stomach and rectum, significantly increased level of serum LAP was observed (p less than 0.01) which contrasted sharply with the normal enzyme values in squamous cell carcinoma of oesophagus and anal canal.