This study was aimed to evaluate demographic, clinical, histological, and virological characteristics of 46 hepatitis C virus (HCV) carriers with persistently normal alanine transaminase (ALT) levels and to compare the results with those obtained in a group of 52 HCV-RNA-positive patients with elevated ALT levels. Subjects with normal ALT were more often females (P < .001), were more likely to be asymptomatic (P < .001), and have a lower incidence of risk factors for HCV transmission (P < .01). All patients with normal ALT had significant histological liver damage. The mean grading and staging did not differ between patients with normal and those with raised ALT concentrations. Moderate to severe hepatitis was more frequently found among subjects with normal than with elevated ALT. HCV genotype 2a was far more common in subjects with normal (43%) than with abnormal ALT levels (6%; P < .002), genotype 1b being more frequent in these latter (50% vs. 17%; P < .001). Patients with normal ALT levels had similar serum HCV-RNA titers than subjects with raised ALT. Neither HCV genotype distribution nor viral load correlated with the severity of liver damage. We conclude that significant liver disease may occur irrespective of clinical symptoms, ALT levels, HCV genotypes, and viral load.
BACKGROUND AND PURPOSEPropranolol is a vasoactive drug that shows antiangiogenic and antitumour activities in melanoma. However, it is unknown whether these activities are dose-dependent and whether there is a relationship between systemic vascular effects of propranolol and anti-melanoma activity. EXPERIMENTAL APPROACHEffects of increasing doses of propranolol (10, 20, 30 and 40 mg·kg À1 ·day À1 ) on tumour growth were studied in B16F10 melanoma-bearing mice. Histological and biochemical analyses were used to assess propranolol effects on angiogenesis and cancer cell proliferation. Systemic vascular resistance (SVR) was evaluated by measuring cardiac output and arterial BP. KEY RESULTSIn vitro analyses revealed that B16F10 cells expressed β-adrenoceptors, but neither isoprenaline, a β-adrenoceptor agonist, nor the β-blocker propranolol affected cancer cell proliferation. In vivo studies showed that the antitumour efficacy of propranolol follows a U-shaped biphasic dose-response curve. Low doses (10 and 20 mg·kg À1 ·day À1 ) significantly inhibit tumour growth, whereas higher doses are progressively less effective. We also found that high-dose propranolol stimulates tumour arteriogenesis whereas no effect on angiogenesis was observed at any dose. Based on these data and considering that propranolol is a vasoactive drug, we hypothesized that it causes systemic vasoconstriction or vasodilation depending on the dose and thus alters tumour perfusion and growth. Consistent with this hypothesis, we found that propranolol has a biphasic effect on SVR with low and high doses producing vasoconstriction and vasodilation respectively. CONCLUSIONS AND IMPLICATIONSPropranolol inhibits melanoma growth in a U-shaped biphasic manner. A direct relationship exists between SVR and antimelanoma activity.Abbreviations α-SMA, α-smooth muscle actin; CO, cardiac output; GAPDH, Glyceraldehyde-3-phosphate dehydrogenase; HR, heart rate; IB4, isolectin B4; SV, stroke volume; SVR, systemic vascular resistance; vWF, Von Willebrand Factor Introduction β-Adrenoceptors are a family of G-protein coupled receptors comprising three subtypes, β 1 , β 2 and β 3 , which act by activating a Gs protein. These receptors play a role in the regulation of peripheral vascular resistance, heart function and airway reactivity, as well as a variety of metabolic and CNS functions. β-Adrenoceptors also regulate cellular processes involved in cancer and angiogenesis and are the molecular target of β-blockers, a class of drugs which inhibits the interaction of catecholamines with β-adrenoceptors.In vitro studies indicate that propranolol, the prototype of β-blockers, reduces melanoma cell proliferation in human and murine melanoma cell lines (Dal Monte et al., 2013;Moretti et al., 2013;Calvani et al., 2015;Wrobel and Le Gal, 2015). Furthermore, the systemic administration of propranolol slows down tumour development in immunodeficient mice transplanted with human melanoma cells (Wrobel and Le Gal, 2015) and inhibits the effects of stress on the growth and metast...
Cardiac dysfunction is often observed in patients with cancer also representing a serious problem limiting chemotherapeutic intervention and even patient survival. In view of the recently established role of the immune system in the control of cancer growth, the present work has been undertaken to investigate the effects of a panel of the most important inflammatory cytokines on the integrity and function of mitochondria, as well as of the cytoskeleton, two key elements in the functioning of cardiomyocytes. Either mitochondria features or actomyosin cytoskeleton organization of in vitro‐cultured cardiomyocytes treated with different inflammatory cytokines were analyzed. In addition, to investigate the interplay between tumor growth and cardiac function in an in vivo system, immunocompetent female mice were inoculated with cancer cells and treated with the chemotherapeutic drug doxorubicin at a dosing schedule able to suppress tumor growth without inducing cardiac alterations. Analyses carried out in cardiomyocytes treated with the inflammatory cytokines, such as tumor necrosis factor α (TNF‐α), interferon γ (IFN‐γ), interleukin 6 (IL‐6), IL‐8, and IL‐1β revealed severe phenotypic changes, for example, of contractile cytoskeletal elements, mitochondrial membrane potential, mitochondrial reactive oxygen species production and mitochondria network organization. Accordingly, in immunocompetent mice, the tumor growth was accompanied by increased levels of the inflammatory cytokines TNF‐α, IFN‐γ, IL‐6, and IL‐8, either in serum or in the heart tissue, together with a significant reduction of ventricular systolic function. The alterations of mitochondria and of microfilament system of cardiomyocytes, due to the systemic inflammation associated with cancer growth, could be responsible for remote cardiac injury and impairment of systolic function observed in vivo.
In HCV carriers with normal aminotransferase levels viraemia does not predict the grade of HCV-related chronic liver disease (CLD), although subjects with higher HCV RNA levels seem to have more severe fibrosis. Although these data suggest that patients with higher viraemia might have more intense architectural changes and more severe progression of liver disease than those with lower levels of HCV replication, the weak and imprecise correlation leads us to conclude that HCV RNA quantitation is not a useful indicator in clinical practice in the selection of patients for liver biopsy.
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