Prostaglandin E2 receptors and COX enzymes in human hepatocellular carcinoma: role in the regulation of cell growth

The aim of this study was to investigate the expression of prostaglandin E(2) receptors (EP(1-4)), cyclooxygenase-1 (COX-1), and COX-2 in nontumor and tumor human liver tissues, and also to evaluate the antitumor activity of selective EP(1) receptor antagonist used alone or in combination with COX-1 and COX-2 selective inhibitors. Semiquantitative PCR analyses revealed that EP(1-4), COX-1, and COX-2 mRNA expression was detected in nearly all the tissue samples assayed, although with a high variability between nontumor and tumor tissues. In vitro EP(1) receptor antagonist inhibited anchorage-independent cell growth and reduced the viability of hepatocellular carcinoma (HCC) cells in a dose-dependent manner. Moreover, treatment with the combination of EP(1) receptor antagonist and COX inhibitors produced a significantly greater cell growth inhibition than the single agent alone. These findings suggest that the EP(1) receptor may represent an important target for HCC treatment, and in addition they could provide preclinical support for a combined chemotherapeutic approach with EP(1) antagonists and COX inhibitors in the treatment of liver cancer.

Cyclooxygenase-2 expression in chronic liver diseases and hepatocellular carcinoma: an immunohistochemical study

Hepatocarcinogenesis is a multistep process characterized by hepatocyte inflammation, regeneration, and proliferation. These changes are believed to depend on the aberrant expression of various tumor suppressor genes, oncogenes and growth factors. Several studies have shown the involvement of cyclooxygenase-2 (COX-2), the inducible isoform of the enzymes that catalyze prostaglandin synthesis in various aspects of carcinogenesis. COX-2 has been described as being overexpressed in hepatocellular carcinoma (HCC) patients. Using immunohistochemistry, we studied COX-2 expression in different chronic liver diseases (CLD) including nonalcoholic steatohepatitis (NASH), chronic hepatitis (CH), liver cirrhosis (LC), and HCC in a population referred to a tertiary center in western Sicily, an area moderately endemic for CLD. Sixteen NASH, 35 CH, 15 LC, and 21 HCC samples were analyzed. Positive signs of COX-2 were observed in the cytoplasm of hepatocytes and median values were 6 (3-9) for NASH, 7 (3-9) for CH, 6 (4-9) for LC, and 4 (0-7) for HCC. COX-2 expression was significantly lower in HCC than in NASH (P < 0.001), CH (P < 0.0001), and LC (P < 0.0001). In HCC we found a wide range of COX-2 expression: from no expression in poorly differentiated areas to a high expression in well-differentiated ones, with an inverse correlation between COX-2 and tumor grading, according to Edmonson (rho=-0.67, P < 0.0001).

IN CONCLUSION

(a) COX-2 expression was significantly lower in HCC than in the other CLD; (b) COX-2 expression inversely correlated with tumor differentiation status. These results suggest that COX-2 expression could be related to the inflammatory phenomena present in the early phases of CLD and eventually to the induction of hepatocarcinogenesis.

Genetic determined downregulation of both type 1 and type 2 cytokine pathways might be protective against pancreatic cancer

Many cytokine polymorphisms have been studied for associations with susceptibility to breast, gastric, liver, lung, prostate, and ovarian cancer without conclusive results. The cytokine network, indeed, is characterized by complex interactions, and the final biological effect of a single genetic variation depends on the balance among different molecular signals. As is well known, Th1/Th2 cytokine unbalanced production might predispose to different pathologies, cancer included. In general, a prolonged type 1 inflammatory response might allow that cells accumulating enough "genetic hits" are promoted to neoplastic transformation. On the other hand, IL-13-producing cells through the IL-13/IL-4 receptor-alpha (R-alpha) pathway might facilitate escape from tumor immunosurveillance. Here are reported data on the evaluation of the influence of some type 2 and type 1 cytokine genetic polymorphisms as risk factors for pancreatic cancer. There was no overall association between pancreatic cancer risk and single cytokine SNPs. On the other hand, in evaluating the influence of combined cytokine genotypes we found that the combined IL-10-1082GA heterozygous and IL-4 Ralpha-1902AA homozygous genotype is underrepresented in the pancreatic cancer subject group. As is well known, the IL-10-1082GA genotype is associated with an intermediate production of this regulatory cytokine, whereas the IL-10-1902AA genotype of the IL-4Ralpha gene is associated with a reduced efficiency in signal transduction when the receptor is engaged by IL-13 or IL-4. These results strongly suggest that a genetic background associated to a mild downregulation of type 1 and type 2 inflammatory signals might be protective against pancreatic cancer.

Androgen metabolism and biotransformation in nontumoral and malignant human liver tissues and cells

There is indirect multiple evidence that hints at a potential role of sex steroids in development and progression of human hepatocellular carcinoma (HCC). In the present study, we have investigated androgen metabolism in a panel of human liver cancer cell lines (HA22T, Huh7, HepG2) and in normal, cirrhotic and malignant human liver tissues aiming to dissect the potential impact of individual enzyme activities and their products in normal and diseased human liver, both in vivo and in vitro. Using our intact cell analysis we were able to assess rates and pathways of androgen metabolism in living conditions. Overall, incubation of cultured cells or tissue minces with either testosterone (T) or androstenedione (Ad) used as precursor resulted in a large extent of 17betaoxidation of T to Ad (cells: 28-77%; tissues: 35-50%). In malignant liver cell lines, both HA22T and Huh7 cells showed consistent amounts of the 5alpha-reductase enzyme products (18% and 15%, respectively), while 5beta-reductase activity was more pronounced in Huh7 cells (18%) than in HA22T cells (1.8%). Interestingly, a significant extent of estrogen formation could be observed in Huh7 cells (5.4-11.5%), while no aromatase activity could be detected in HA22T cells. In HepG2 cells, along with a relatively high proportion of Ad, estrogens represented the most prominent (50-55%) end product of androgen metabolism, regardless of the precursor used. In liver tissues, equivalent results could be obtained, with a consistent proportion of 17betaoxidation of T to Ad (35-50%) being observed in the majority of samples. However, while normal liver tissue samples exhibited a minor proportion of bioactive androgens (3.4%) with no aromatase products, HCC tissues showed a significant extent of aromatase activity (nearly 20%) with estrogen representing the most prominent metabolic product after 24h incubation with either T or Ad. HCV and alcoholic cirrhotic tissues displayed different patterns of androgen metabolism. The former produced limited amounts of bioactive androgens (5.3%) and considerable levels of the intermediate aromatase product 19OH-Ad (up to 28%), the latter exhibited a prevalence of androgen degradation through the 5beta-reductase pathway (9.8%) and a significant extent of aromatase activity (16% as a whole). In conclusion, three major metabolic states could be depicted, depending on prevalent pathways of androgen metabolism and steroid receptor status: estrogenic, androgenic, and mixed. This model supports the idea that local estrogen biosynthesis may be implicated in human HCC and provides a basis for the exploitation of aromatase inhibitors and/or ER antagonists or selective estrogen receptor modulators (SERMs) as a new therapeutic strategy in HCC patients.

Aromatase and amphiregulin are correspondingly expressed in human liver cancer cells

Human hepatocellular carcinoma (HCC) is associated with high mortality rates, being the third most common cause of cancer death worldwide. Although estrogens have been implicated in HCC, their potential role in development and/or progression of this malignancy remains unclear. In this study we investigated mRNA and protein expression of aromatase (Aro) and amphiregulin (AREG) in relation to estrogen receptors (ERs), in HepG2, Huh7, and HA22T human malignant liver cell lines, using RT-PCR and Western blot analyses. Aro expression was significantly higher (approximately 13-fold, P= 0.003) in HepG2 cells than in Huh7 cells, while no Aro expression could be detected in HA22T cells. Interestingly, the patterns of AREG expression were consistently associated with those of Aro, with approximately 3-fold and approximately 8-fold higher levels being seen in HepG2 cells than in Huh7 cells (P= 0.002) and HA22T cells (P= 0.0014), respectively. Using a specific set of primers, ERalpha46 is the only ER variant expressed in all cell lines, while the wild-type ERalpha66 could not be detected. Western blot analysis revealed a corresponding figure. This evidence suggests that AREG expression may be upregulated by estrogens in human HCC and that locally elevated aromatase activity also may increase malignant cell proliferation through AREG signaling.

Early discontinuation of ribavirin in HCV-2 and HCV-3 patients responding to Peg-interferon alpha-2a and ribavirin

Guidelines for the treatment of patients infected with hepatitis C virus of genotypes 2 and 3 (HCV-2 and HCV-3, respectively) recommend a 24-week course of Peg-interferon (Peg-IFN) alpha-2a combined with ribavirin, despite 50% of patients in registration trials attaining a sustained virologic response (SVR) following Peg-IFN alpha-2a monotherapy. The aim of this study was to delineate patient characteristics that might help to identify individuals likely to benefit from ribavirin discontinuation. One hundred and forty-four HCV-2- and HCV-3-infected patients initiated Peg-IFN alpha-2a (180 microg/week) and ribavirin (1000 or 1200 mg/day); those with viral clearance at week 4 were randomized to either Peg-IFN alpha-2a monotherapy (n = 59) or continuing combination therapy (n = 61) until week 12. Overall, all but one patient with a rapid virologic response (RVR) responded by the end of therapy and the overall SVR rates were lower after discontinuation of ribavirin (54%vs 82%; P < 0.001). In RVR patients who discontinued ribavirin, low baseline viraemia helped predict SVR (odds ratio 11.2, 95% CI 2.7-47.1). SVR rates were similar in patients receiving mono- or combination therapy with low (< or =300,000 IU/mL) and intermediate viraemia (86%vs 81% and 70%vs 71%, 86% refers to low viraemic patients receiving monotherapy and 81% to those receiving combination therapy. Similarly, 70% refers to patients with intermediate viraemic levels receiving monotherapy and 71% to those receiving combination therapy), but different in those with high (>700,000 IU/mL) viraemia (37%vs 88%; P = 0.004). Thus in HCV-2- and HCV-3-infected patients, withdrawal of ribavirin and continuation of Peg-IFN alpha-2a monotherapy may be appropriate to attain an SVR, providing viraemia is cleared early during therapy and associated with low baseline viral load. These results warrant future investigations, as discontinuing ribavirin could lead to considerable savings in cost and quality of life related to over-treatment.

[Abnormal liver function in brucellosis]

We assessed the prevalence of impaired liver function in 47 patients suffering from brucellosis consecutively admitted to our department over the last five years. Parameters of liver function and ultrasound of the upper abdomen were performed at entry and at the end of treatment. On admission, mean transaminase values were elevated and significantly higher than at recovery (p 0.001): 38 percent and 53 percent of patients had elevated baseline values of GOT and GPT vs 13 and 19% at the end of treatment, respectively. Mean serum values of alkaline phosphatase (AP) were within normal limits on admission, although in 12 of them serum values were elevated. The same proportion was seen for gamma-glutamyltranspeptidase. Both transaminases and AP were elevated in 8 patients (17 percent). There were no significant differences in serum values of albumin and bilirubin before and after therapy. The platelet count slightly decreased, but not significantly, during the acute phase of disease. At ultrasound one third of the patients showed hepatomegaly with a hepatitis-like pattern and 40 percent of patients had splenomegaly. In conclusion, this study confirms data in the literature showing a high frequency of liver impairment during the course of brucellosis, which is usually mild-moderate.

Solitary necrotic nodule of the liver: different pathological findings express a different histogenesis

Solitary necrotic nodule of the liver is a rare benign lesion the histogenesis of which is still debated. We here report the case of a patient who underwent laparoscopic cholecystectomy for gallstones and who was accidentally found to have a solitary necrotic nodule of 2 cm in the fifth segment of the liver. On the basis of the histological findings, the hypothesis that different pathogenetic mechanisms could be involved in the histogenesis of this lesion is discussed.

Individualized treatment duration for hepatitis C genotype 1 patients: A randomized controlled trial

It was hypothesized that in hepatitis C virus (HCV) genotype 1 patients, variable treatment duration individualized by first undetectable HCV RNA is as effective as standard 48-week treatment. Patients (n = 696) received peginterferon alfa-2a, 180 mg/week, or peginterferon alfa-2b, 1.5 mg/kg/week, plus ribavirin, 1000-1200 mg/day, for 48 weeks (standard, n = 237) or for 24, 48, or 72 weeks if HCV-RNA-negative at weeks 4, 8, or 12, respectively (variable, n = 459). Sustained virologic response (SVR) was achieved in 45.1% [95% confidence interval (CI) 38.8-51.4] of the patients in the standard group and in 48.8% (CI 44.2-53.3) of the patients in the variable group (P = 0.37). The percentages of patients who first achieved undetectable HCV RNA at weeks 4, 8, or 12 were 26.7%, 27.8%, and 11.3%, respectively. In the standard treatment group, 87.1%, 70.3%, and 38.1% of patients who first achieved undetectable HCV RNA at 4, 8, or 12 weeks attained SVRs, respectively. In the variable group, corresponding SVR rates were 77.2%, 71.9%, and 63.5%. Low viremia levels and young age were independent predictors of response at week 4 [rapid virologic response (RVR)]. RVR patients with baseline viremia >or=400,000 IU/mL achieved higher SVR rates when treated for 48 weeks rather than 24 weeks (86.8% versus 73.1%, P = 0.14). The only predictive factor of SVR in RVR patients was advanced fibrosis.

CONCLUSION

Variable treatment duration ensures SVR rates similar to those of standard treatment duration, sparing unnecessary side effects and costs.

[Patient satisfaction in hemodialysis: a pilot cross-sectional analysis and a review]

BACKGROUND

Assessment of patient satisfaction is not performed routinely in many healthcare institutions. In this review, we discuss methodological aspects of assessment of patient satisfaction in hemodialysis. We also present a pilot study conducted in the Gambro Healthcare Italy dialysis clinics network.

METHODS

Patient satisfaction was assessed in a network of hemodialysis units by using an internally validated Italian translation of the Choices for Healthy Outcomes in Caring for ESRD (CHOICE) questionnaire. A cross-sectional analytic study design was used and data analysed with univariate and multivariate hierarchical logistic regression to explore correlates of the risk of being unsatisfied with dialysis treatment. Covariates which were considered include a series of over 20 clinical, demographic, organizational and structural aspects. In addition, unexplained inter-centre residual variability due to 'case-mix' was explored and plotted.

RESULTS

Seventeen dialysis units participated in this cross-sectional analysis and 758/1001 (75.7%) provided answers to the questionnaires. There was a statistically significant association on multivariate hierarchical analysis between the risk of being unsatisfied with dialysis treatment and interdialysis body weight gain (unit of increase: 1 kg, p=0.004). On the contrary, the risk of unsatisfaction with dialysis treatment was significantly lower in patients with higher dry weight (unit of increase: 1 kg, p=0.002). Our multivariate hierarchical analysis identified some residual variability between dialysis units (n=6 outliers) which may not be explained by any of over 20 potential confounding covariates which were explored.

CONCLUSIONS

Assessment of ''customer satisfaction'' is standard practice in private for profit product companies in general but needs to be increasingly recognized as a standard in both public and private providers of healthcare services. Social research methods, which are used for this type of analysis, need to be fine tuned and actively implemented in order to better understand how we may influence the quality of service we provide to our patients and the level at which they rate it.

Circulating Levels of Adhesion Molecules in Chronic Kidney Disease Correlate with the Stage of Renal Disease and with C-Reactive Protein

BACKGROUND

Patients with chronic renal failure (CRF) suffer from a series of complications linked to the atherosclerotic process in which the endothelial dysfunction mediated by the activation of some adhesion molecules plays an important role. This study aims to evaluate circulating levels of intercellular adhesion molecules-1 (ICAM-1) and vascular cell adhesion molecules-1 (VCAM-1) in patients with predialysis CRF, on maintenance hemodialysis (HD) and after kidney transplantation (KTx) and to correlate them with some inflammation and nutritional indexes.

METHODS

Thirty two patients with predialysis CRF, 30 on maintenance HD, 36 after KTx and 28 subjects as a control group (C) were included in this study. Circulating levels of ICAM-1 and VCAM-1 were assayed using a specific sandwich ELISA kit. As inflammation indexes, TNFalpha and C-reactive protein (CRP) and, as nutritional indexes, body mass index (BMI), serum albumin, cholesterol, triglycerides, and fibrinogen (F) were evaluated.

RESULTS

Serum levels of ICAM-1 and VCAM-1 were progressively higher from C to KTx patients, to those with CRF and those on HD (ANOVA for both; p <0.001). TNFalpha values were lower in HD subjects than in CRF patients, even if in both groups TNFalpha levels were greater than in Tx and control subjects. F and CRP were higher in CRF and HD vs. Tx and control subjects (ANOVA for both p <0.001). No significant correlations were observed between soluble adhesion molecules, albumin and cholesterol, whereas significant correlations were found between CRP and ICAM-1 (r = 0.41; p <0.01), CRP and VCAM-1 (r = 0.39; p <0.01) and between CRP and TNFalpha (r = 0.42; p <0.01). These correlations remained statistically significant even after adjustment for age and blood pressure (all p <0.01). BMI did not differ in the three patient groups.

CONCLUSIONS

Circulating levels of adhesion molecules in our study correlated positively with the stage of disease and with one of the inflammatory indexes (CRP), but not with nutritional indexes such as BMI, cholesterol and albumin. The clinical significance of our findings warrants further investigation.

Histamine and spontaneously released mast cell granules affect the cell growth of human hepatocellular carcinoma cells

The role of mast cells in tumor growth is still controversial. In this study we analyzed the effects of both histamine and pre-formed mediators spontaneously released by mast cells on the growth of two human hepatocellular carcinoma cell lines, HA22T/VGH and HuH-6, with different characteristics of differentiation, biological behavior and genetic defects. We showed that total mast cell releasate, exocytosed granules (granule remnants) and histamine reduced cell viability and proliferation in HuH-6 cells. In contrast, in HA22T/VGH cells granule remnants and histamine induced a weak but significant increase in cell growth. We showed that both cell lines expressed histamine receptors H(1) and H(2) and that the selective H(1) antagonist terfenadine reverted the histamine-induced inhibition of HuH-6 cell growth, whereas the selective H(2) antagonist ranitidine inhibited the histamine-induced cell growth of HA22T/VGH cells. We demonstrated that histamine down-regulated the expression of beta-catenin, COX-2 and survivin in HuH-6 cells and that this was associated with caspase-3 activation and PARP cleavage. On the contrary, in HA22T/VGH cells expression of survivin and beta-catenin increased after treatment with granule remnants and histamine. Overall, our results suggest that mediators stored in mast cell granules and histamine may affect the growth of liver cancer cells. However, mast cells and histamine may play different roles depending on the tumor cell features. Finally, these data suggest that histamine and histamine receptor agonists/antagonists might be considered as "new therapeutic" drugs to inhibit liver tumor growth.

[Abnormal liver function in Mediterranean spotted fever]

In this study we retrospectively assessed the prevalence of impaired liver function in all 49 patients suffering from Mediterranean Spotted Fever (MSF) consecutively admitted to our department over the last four years. The main parameters of liver function and ultrasound of upper abdomen were performed at entry and at the end of treatment. At admission mean values of transaminases were above the normal limits and significantly higher when compared to mean serum levels at recovery. 55% and 51% of patients had serum values of GOT and GPT, respectively, above the normal limits versus 1% and 2% at the end of treatment. Mean serum values of alkaline phosphatase (AP) were within the normal limits at entry in hospital, but 22 of them had serum values above the normal limits. The same proportion was seen for gamma glutamiltranspeptidase values. Eighteen patients (36.7%) had both transaminases and AP above the normal limits. There were no significant differences among serum values of albumin, bilirubin and gamma globulin before and after therapy. Platelet count, on the contrary, was significantly reduced at admission (p < 0.0001). At ultrasound half of the patients showed hepatomegaly with a hepatitis-like pattern and 39% of patients had splenomegaly. In conclusion, this study confirms previous data from the literature showing a high frequency of liver impairment during the course of MSF, which is usually mild-moderate. In a few cases, however, the increase of transaminases could be serious and the recovery delayed, but never, in our experience, has there been progression toward chronic liver disease.

Celiac disease in the developing countries: A new and challenging public health problem

In the past, celiac disease was believed to be a chronic enteropathy, almost exclusively affecting people of European origin. The availability of new, simple, very sensitive and specific serological tests (anti-gliadin, anti-endomysium and anti-transglutaminase antibody assays) have shown that celiac disease is common not only in Europe and in people of European ancestry but also in the developing countries where the major staple diet is wheat (Southern Asia, the Middle East, North West and East Africa, South America), both in the general population and in the groups at risk. Gluten intolerance thus appears to be a widespread public health problem and an increased level of awareness and clinical suspicion are needed in the New World where physicians must learn to recognize the variable clinical presentations (classical, atypical and silent forms) of celiac disease. In the developing countries, both serological screening in the general population and serological testing in groups at risk are necessary for an early identification of celiac patients. The gluten-free diet poses a challenging public health problem in the developing countries, especially since commercial gluten-free products are not available.

Multifactorial nature of hepatocellular carcinoma drug resistance: could plant polyphenols be helpful?

Primary hepatocellular carcinoma (HCC) is a quite frequent tumor which results in high mortality and most often exhibits a poor response to present drug therapies. Clearly, a thorough understanding of the biological bases of this malignancy might suggest new strategies for its treatment. Here we examine the evidences that both "pharmacological" mechanisms (e.g. drug transporter or detoxification enzyme over-expression) and alterations in other critical factors, including the IAPs (Inhibitory of Apoptosis Proteins), involved in enhancement of cell survival and proliferation may determine the therapeutic resistance of HCC; we also underline the possible role in the process of the activation of transcription factors, like NF-kappaB, capable of contemporaneously up-regulating the mechanisms discussed. On this basis, we finally comment on the possible use of natural multi-targeted antitumoral agents like plant polyphenols to achieve sensitization to treatments in HCC.

Significance of autologous interleukin-6 production in the HA22T/VGH cell model of hepatocellular carcinoma

Cancer cells may often support their own growth, survival, and drug resistance by autocrine/paracrine loops based on the production of different factors; results from us and others have shown that similar interleukin-6 (IL-6)-related loops are operative in multiple myeloma and prostate or renal cancer. Because this aspect has not been investigated in detail for hepatocellular carcinoma (HCC), we have examined it in HA22T/VGH cells. These differ from other primary liver cancer cell lines (that is, HepG2, HuH-6, and HuH-7) in that enzyme-linked immunosorbent assay (ELISA) showed the HA22T/VGH cells to secrete remarkable amounts of IL-6 (16.8 ng/10(6) cells/24 h); this production, due to constitutive activation of NF-kappaB, is inhibited by agents like curcumin and dehydroxymethylepoxyquinomicin (DHMEQ), which interfere with the transcription factor. Flow cytometry, ELISA, mRNA, and Western blotting analyses were performed to characterize the status of the IL-6 receptor in HA22T/VGH cells. Two transmembrane glycoproteins that form the functional IL-6 receptor have been identified: the ligand-binding gp80 and the signal-transducer gp130. Soluble forms of gp80 also trigger membrane gp130 signaling when complexed with IL-6, while soluble forms of gp130 inhibit the same process. Our results showed that HA22T/VGH cells express gp130 at their surface, but release only traces of its soluble form. For gp80, the cells produced the mRNAs of both its membrane and soluble form. However, in immunoblotting they exhibited a very faint content of the same subunit, which, in addition, was neither expressed at the cell surface nor secreted. In MTT assays, incubation with a neutralizing anti-IL-6 antibody for up to 7 days did not affect the growth of HA22T/VGH cells. Also, other specific anti-IL-6 approaches (siRNA or AODN) failed to produce this result. In conclusion, autostimulatory loops mediated by IL-6 are less likely to occur in HCC than in other kinds of cancer. However, since release of IL-6 is frequent in HCC, especially in its more advanced stages, the use of agents like curcumin or DHMEQ might be beneficial to counteract its adverse systemic effects (e.g., cachexia).

Sex hormones and risk of liver tumor

The liver is morphologically and functionally modulated by sex hormones. Long-term use of oral contraceptives (OCs) and anabolic androgenic steroids (AASs) can induce both benign (hemangioma, adenoma, and focal nodular hyperplasia [FNH]) and malignant (hepatocellular carcinoma [HCC]) hepatocellular tumors. Hepatic adenomas (HAs) are rare, benign neoplasms usually occurring in young women, the development and the complications of which have been related to the strength of OCs and the duration of their use. HA incidence has fallen since the introduction of pills containing smaller amounts of estrogens. FNH is a benign lesion, most commonly seen in young women, which is thought to represent a local hyperplastic response of hepatocytes to a vascular abnormality. Because of the female predominance and the young age at onset, a role of female hormones has been suggested. Furthermore, a large proportion of women with FNH (50-75%) are OC users. Liver hemangiomas (LHs) are the most common benign liver tumors and are seen more commonly in young adult females. The female predilection and clinical observations of LH growth under conditions of estrogenic exposure suggest a possible role for estrogen in the pathogenesis of LHs. HCC has become one of the most widespread tumors in the world in recent years, representing the sixth leading cancer and the third most common cause of death from cancer. Apart from liver cirrhosis, numerous other factors responsible for its onset have been proposed: hepatitis infections from virus B (HBV) and C (HCV), alcohol, smoking, and aflatoxin. However, regardless of etiology, chronic liver diseases progress at unequal rates in the two sexes, with the major sequelae, such as cirrhosis and HCC, being more frequent in men than in women. These epidemiological data have prompted researchers to investigate the relationship between sex hormones and liver tumors. The human liver expresses estrogen and androgen receptors and experimentally both androgens and estrogens have been implicated in stimulating hepatocyte proliferation and may act as liver tumor inducers or promoters.

Food allergy in gastroenterologic diseases: Review of literature

Food allergy is a common and increasing problem worldwide. The newly-found knowledge might provide novel experimental strategies, especially for laboratory diagnosis. Approximately 20% of the population alters their diet for a perceived adverse reaction to food, but the application of double-blind placebo-controlled oral food challenge, the “gold standard” for diagnosis of food allergy, shows that questionnaire-based studies overestimate the prevalence of food allergies. The clinical disorders determined by adverse reactions to food can be classified on the basis of immunologic or nonimmunologic mechanisms and the organ system or systems affected. Diagnosis of food allergy is based on clinical history, skin prick tests, and laboratory tests to detect serum-food specific IgE, elimination diets and challenges. The primary therapy for food allergy is to avoid the responsible food. Antihistamines might partially relieve oral allergy syndrome and IgE-mediated skin symptoms, but they do not block systemic reactions. Systemic corticosteroids are generally effective in treating chronic IgE-mediated disorders. Epinephrine is the mainstay of treatment for anaphylaxis. Experimental therapies for IgE-mediated food allergy have been evaluated, such as humanized IgG anti-IgE antibodies and allergen specific immunotherapy.

Thyroid sarcoidosis as a unique localization

Sarcoidosis is a systemic disorder characterized by granulomatous lesions, principally affecting the lungs. There are numerous reports in the literature of an associated involvement of the thyroid, much more frequently in hypothyroid than in hyperthyroid subjects. The present case report refers to a woman presenting with thyroid nodules and normal biochemical levels and thyroid function parameters, while histology revealed sarcoid-type lesions. Subsequent investigations and a long follow-up showed no evidence of involvement of other sites, including the lungs. Consequently, after a long period of normal health associated with the negative results of the examinations, a diagnosis of sarcoidosis limited to the thyroid was proposed, which was cured by thyroidectomy.

Impact of liver steatosis on the antiviral response in the hepatitis C virus-associated chronic hepatitis

BACKGROUND/AIM

Liver steatosis (LS) has been variably associated with chronic hepatitis C (CHC) but whether it affects sustained virological response to antiviral treatment and by what mechanisms is a question still under debate, at least for some genotypes. The aim of this work was to assess the frequency of LS, its relationship with host and viral factors and to what extent it can influence the response to antiviral combination therapy with pegylated interferon (INF)+ribavirin in a group of patients with CHC from a single center.

PATIENTS

One hundred and twelve patients with histologically proven CHC were treated with Peg INF-alpha 2a 180 microg a week subcutaneously for 48 weeks plus ribavirin 1000 or 1200 mg/day, according to the patient's body weight. Steatosis was graded according to Brunt et al.

RESULTS

Forty-six out of 112 patients (41.1%) were sustained virological responders (SVR). Seventy-two out of 112 (64.3%) presented with LS at histology; in this group, there were 24 patients (33.3%) with SVR compared with 22 (55%) of the non-steatosis group (chi(2)=6.5, P<0.02). Variables associated with the steatosis group were: higher serum levels of AST (P<0.04), alanine aminotransferase (P<0.02), gamma-GT (P<0.004), genotype 3a (P<0.03) and severity of histology (staging P<0.05) but at multiple linear regression analysis only genotype 3a and staging were significantly associated with LS. In the SVR group, age and body mass index (BMI) were significantly lower (P<0001 and P<0.03, respectively) compared with non-responders; moreover, genotype 1 was more frequent in the NR group, while genotype 3 was more frequent in the SVR group. At histology, grading and staging were also lower in the SVR group. Multiple logistic regression showed that only the grade of steatosis and genotype 3a were the variables independently associated with SVR.

CONCLUSIONS

This study showed a frequency of LS on the higher side of the range so far reported in the literature and confirmed that it negatively influences response to therapy. Genotype1 was confirmed to be the most frequent type in our area. It is more frequent in patients with mild-moderate steatosis and seems to condition therapeutic response negatively, together with BMI and age. In contrast, genotype 3a is more frequent in patients with severe steatosis, but is a favorable predictor of successful therapy.

Cyclooxygenases in hepatocellular carcinoma

Many epidemiological studies demonstrate that treatment with non-steroidal anti-inflammatory drugs (NSAIDs) reduce the incidence and mortality of certain malignancies, especially gastrointestinal cancer. The cyclooxygenase (COX) enzymes are well-known targets of NSAIDs. However, conventional NSAIDs non-selectively inhibit both the constitutive form COX-1, and the inducible form COX-2. Recent evidence indicates that COX-2 is an important molecular target for anticancer therapies. Its expression is undetectable in most normal tissues, and is highly induced by pro-inflammatory cytokines, mitogens, tumor promoters and growth factors. It is now well-established that COX-2 is chronically overexpressed in many premalignant, malignant, and metastastic cancers, including hepatocellular carcinoma (HCC). Overexpression of COX-2 in patients with HCC is generally higher in well-differentiated HCCs compared with less-differentiated HCCs or histologically normal liver, suggesting that COX-2 may be involved in the early stages of hepatocarcinogenesis, and increased expression of COX-2 in noncancerous liver tissue has been significantly associated with shorter disease-free survival in patients with HCC.

In tumors, overexpression of COX-2 leads to an increase in prostaglandin (PG) levels, which affect many mechanisms involved in carcinogenesis, such as angiogenesis, inhibition of apoptosis, stimulation of cell growth as well as the invasiveness and metastatic potential of tumor cells.

The availability of novel agents that selectively inhibit COX-2 (COXIB), has contributed to shedding light on the role of this molecule. Experimental studies on animal models of liver cancer have shown that NSAIDs, including both selective and non-selective COX-2 inhibitors, exert chemopreventive as well as therapeutic effects. However, the key mechanism by which COX-2 inhibitors affect HCC cell growth is as yet not fully understood.

Increasing evidence suggests the involvement of molecular targets other than COX-2 in the anti-proliferative effects of COX-2 selective inhibitors. Therefore, COX-inhibitors may use both COX-2-dependent and COX-2-independent mechanisms to mediate their antitumor properties, although their relative contributions toward the in vivo effects remain less clear.

Here we review the features of COX enzymes, the role of the expression of COX isoforms in hepatocarcinogenesis and the mechanisms by which they may contribute to HCC growth, the pharmacological properties of COX-2 selective inhibitors, the antitumor effects of COX inhibitors, and the rationale and feasibility of COX-2 inhibitors for the treatment of HCC.

Interleukin-6 and its soluble receptor in patients with liver cirrhosis and hepatocellular carcinoma

AIM

To evaluate the immunohistochemical localization of interleukin-6 (IL-6) and IL-6 receptor (IL-6R) on tumor tissue specimens from patients with hepatocellular carcinoma (HCC) and the serum levels of IL-6 and sIL-6R in a group of patients with HCC as well as liver cirrhosis (LC) in a group of patients with LC alone and in a control group.

METHODS

Three groups of subjects were studied: group I (n = 83) suffering from HCC and LC, group II (n = 72) suffering from LC alone and group III (n = 42) as healthy controls. All patients had hepatitis C virus infection. Serum IL-6 and IL-6R levels were determined using a commercially available ELISA kit. Immunohistochemistry was performed using the streptavidin-biotin complex and rabbit polyclonal antibodies against IL-6 and IL-6R.

RESULTS

Immunohistochemistry analysis showed a medium to strong cytoplasmic and membrane reactivity for IL-6 and IL-6R respectively, in at least 40% of cases of HCC, whereas liver cirrhosis patients and controls were negative for IL-6 or showed a very mild and focal dot-like cytoplasmic reaction for IL-6R. Serum IL-6 levels in HCC group were significantly higher than those in LC and control groups (P < 0.0001). There was no significant difference in sIL-6R concentrations among 3 groups. When the patients with HCC were divided into groups according to Okuda's classification, a significant serum increase of IL-6 and sIL-6R level was observed from stage I to stage III (P < 0.02, P < 0.0005). When HCC and LC patients were divided into 3 classes of cirrhosis severity according to Child-Pugh, values in HCC patients were significantly higher than those in LC patients for each corresponding class (P < 0.01).

CONCLUSION

IL-6 serum levels in HCC patients are higher than those in LC patients and controls, suggesting an increased production of this cytokine by neoplastic cells. sIL-6R values are similar in all groups, increasing only in stage III HCC patients. These data suggest that they have a closer relationship with the neoplastic mass rather than with the residual functioning hepatic mass.