PNPLA3 I148M Polymorphism,Clinical Presentation,and Survival in Patients with Hepatocellular Carcinoma

Background & Aims

Aim of this study was to evaluate whether the PNPLA3 I148M polymorphism, previously associated with hepatocellular carcinoma (HCC) risk, influences the clinical presentation of HCC and survival.

Methods

we considered 460 consecutive HCC patients referred to tertiary care centers in Northern Italy, 353 with follow-up data.

Results

Homozygosity for PNPLA3 148M at risk allele was enriched in HCC patients with alcoholic liver disease or nonalcoholic fatty liver disease (ALD&NAFLD: relative risk 5.9, 95% c.i. 3.5–9.9; other liver diseases: relative risk 1.9, 95% c.i. 1.1–3.4). In ALD&NAFLD patients, the PNPLA3 148M allele was associated with younger age, shorter history of cirrhosis, less advanced (Child A) cirrhosis at HCC diagnosis, and lower HCC differentiation grade (p<0.05). Homozygosity for PNPLA3 148M was associated with reduced survival in the overall series (p = 0.009), and with a higher number of HCC lesions at presentation (p = 0.007) and reduced survival in ALD&NAFLD patients (p = 0.003; median survival 30, 95% c.i. 20–39 vs. 45, 95% c.i. 38–52 months), but not in those with HCC related to other etiologies (p = 0.86; 48, 95% c.i. 32–64 vs. 55, 95% c.i. 43–67 months). At multivariate Cox regression analysis, homozygosity for PNPLA3 148M was the only negative predictor of survival in ALD&NAFLD patients (HR of death 1.57, 95% c.i. 1.12–2.78).

Conclusions

PNPLA3 148M is over-represented in ALD&NAFLD HCC patients, and is associated with occurrence at a less advanced stage of liver disease in ALD&NAFLD. In ALD&NAFLD, PNPLA3 148M is associated with more diffuse HCC at presentation, and with reduced survival.     

Echocardiography,Spirometry, and Systemic Acute-Phase Inflammatory Proteins in Smokers with COPD or CHF: An Observational Study

Chronic obstructive pulmonary disease (COPD) and chronic heart failure (CHF) may coexist in elderly patients with a history of smoking. Low-grade systemic inflammation induced by smoking may represent the link between these 2 conditions. In this study, we investigated left ventricular dysfunction in patients primarily diagnosed with COPD, and nonreversible airflow limitation in patients primarily diagnosed with CHF. The levels of circulating high-sensitive C-reactive protein (Hs-CRP), pentraxin 3 (PTX3), interleukin-1β (IL-1 β), and soluble type II receptor of IL-1 (sIL-1RII) were also measured as markers of systemic inflammation in these 2 cohorts. Patients aged ≥50 years and with ≥10 pack years of cigarette smoking who presented with a diagnosis of stable COPD (n=70) or stable CHF (n=124) were recruited. All patients underwent echocardiography, N-terminal pro-hormone of brain natriuretic peptide measurements, and post-bronchodilator spirometry. Plasma levels of Hs-CRP, PTX3, IL-1 β, and sIL-1RII were determined by using a sandwich enzyme-linked immuno-sorbent assay in all patients and in 24 healthy smokers (control subjects). Although we were unable to find a single COPD patient with left ventricular dysfunction, we found nonreversible airflow limitation in 34% of patients with CHF. On the other hand, COPD patients had higher plasma levels of Hs-CRP, IL1 β, and sIL-1RII compared with CHF patients and control subjects (p < 0.05). None of the inflammatory biomarkers was different between CHF patients and control subjects. In conclusion, although the COPD patients had no evidence of CHF, up to one third of patients with CHF had airflow limitation, suggesting that routine spirometry is warranted in patients with CHF, whereas echocardiography is not required in well characterized patients with COPD. Only smokers with COPD seem to have evidence of systemic inflammation.     

Human Glioblastoma Multiforme: p53 Reactivation by a Novel MDM2 Inhibitor

Cancer development and chemo-resistance are often due to impaired functioning of the p53 tumor suppressor through genetic mutation or sequestration by other proteins. In glioblastoma multiforme (GBM), p53 availability is frequently reduced because it binds to the Murine Double Minute-2 (MDM2) oncoprotein, which accumulates at high concentrations in tumor cells. The use of MDM2 inhibitors that interfere with the binding of p53 and MDM2 has become a valid approach to inhibit cell growth in a number of cancers; however little is known about the efficacy of these inhibitors in GBM. We report that a new small-molecule inhibitor of MDM2 with a spirooxoindolepyrrolidine core structure, named ISA27, effectively reactivated p53 function and inhibited human GBM cell growth in vitro by inducing cell cycle arrest and apoptosis. In immunoincompetent BALB/c nude mice bearing a human GBM xenograft, the administration of ISA27 in vivo activated p53, inhibited cell proliferation and induced apoptosis in tumor tissue. Significantly, ISA27 was non-toxic in an in vitro normal human cell model and an in vivo mouse model. ISA27 administration in combination with temozolomide (TMZ) produced a synergistic inhibitory effect on GBM cell viability in vitro, suggesting the possibility of lowering the dose of TMZ used in the treatment of GBM. In conclusion, our data show that ISA27 releases the powerful antitumor capacities of p53 in GBM cells. The use of this MDM2 inhibitor could become a novel therapy for the treatment of GBM patients.     

The Ku Heterodimer and the Metabolism of Single-Ended DNA Double-Strand Breaks

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SUMF1 enhances sulfatase activities in vivo in five sulfatase deficiencies

Sulfatases are enzymes that hydrolyse a diverse range of sulfate esters. Deficiency of lysosomal sulfatases leads to human diseases characterized by the accumulation of either GAGs (glycosaminoglycans) or sulfolipids. The catalytic activity of sulfatases resides in a unique formylglycine residue in their active site generated by the post-translational modification of a highly conserved cysteine residue. This modification is performed by SUMF1 (sulfatase-modifying factor 1), which is an essential factor for sulfatase activities. Mutations in the SUMF1 gene cause MSD (multiple sulfatase deficiency), an autosomal recessive disease in which the activities of all sulfatases are profoundly reduced. In previous studies, we have shown that SUMF1 has an enhancing effect on sulfatase activity when co-expressed with sulfatase genes in COS-7 cells. In the present study, we demonstrate that SUMF1 displays an enhancing effect on sulfatases activity when co-delivered with a sulfatase cDNA via AAV (adeno-associated virus) and LV (lentivirus) vectors in cells from individuals affected by five different diseases owing to sulfatase deficiencies or from murine models of the same diseases [i.e. MLD (metachromatic leukodystrophy), CDPX (X-linked dominant chondrodysplasia punctata) and MPS (mucopolysaccharidosis) II, IIIA and VI]. The SUMF1-enhancing effect on sulfatase activity resulted in an improved clearance of the intracellular GAG or sulfolipid accumulation. Moreover, we demonstrate that the SUMF1-enhancing effect is also present in vivo after AAV-mediated delivery of the sulfamidase gene to the muscle of MPSIIIA mice, resulting in a more efficient rescue of the phenotype. These results indicate that co-delivery of SUMF1 may enhance the efficacy of gene therapy in several sulfatase deficiencies.     

Extended-spectrum beta-lactamase CTX-M-1 in Escherichia coli isolates from healthy poultry in France

Genes encoding extended-spectrum beta-lactamase CTX-M-1 were detected in 12 Escherichia coli isolates recovered over a 7-month period from the ceca of healthy poultry in seven districts in France in 2005. Eleven of those strains were not clonally related and had a bla(CTX-M-1) gene located on transferable plasmids of different sizes and structures.     

p27Kip1 serine 10 phosphorylation determines its metabolism and interaction with cyclin-dependent kinases

p27Kip1 is a critical modulator of cell proliferation by controlling assembly, localization and activity of cyclin-dependent kinase (CDK). p27Kip1 also plays important roles in malignant transformation, modulating cell movement and interaction with the extracellular matrix. A critical p27Kip1 feature is the lack of a stable tertiary structure that enhances its “adaptability” to different interactors and explains the heterogeneity of its function. The absence of a well-defined folding underlines the importance of p27Kip1 post-translational modifications that might highly impact the protein functions. Here, we characterize the metabolism and CDK interaction of phosphoserine10-p27Kip1 (pS10- p27Kip1), the major phosphoisoform of p27Kip1. By an experimental strategy based on specific immunoprecipitation and bidimensional electrophoresis, we established that pS10-p27Kip1 is mainly bound to cyclin E/CDK2 rather than to cyclin A/CDK2. pS10- p27Kip1 is more stable than non-modified p27Kip1, since it is not (or scarcely) phosphorylated on T187, the post-translational modification required for p27Kip1 removal in the nucleus. pS10-p27Kip1 does not bind CDK1. The lack of this interaction might represent a mechanism for facilitating CDK1 activation and allowing mitosis completion. In conclusion, we suggest that nuclear p27Kip1 follows 2 almost independent pathways operating at different rates. One pathway involves threonine-187 and tyrosine phosphorylations and drives the protein toward its Skp2-dependent removal. The other involves serine-10 phosphorylation and results in the elongation of p27Kip1 half-life and specific CDK interactions. Thus, pS10-p27Kip1, due to its stability, might be thought as a major responsible for the p27Kip1-dependent arrest of cells in G1/G0 phase.     

Trichoderma spp. alleviate phytotoxicity in lettuce plants (Lactuca sativa L.) irrigated with arsenic-contaminated water

The influence of two strains of Trichoderma (T. harzianum strain T22 and T. atroviride strain P1) on the growth of lettuce plants (Lactuca sativa L.) irrigated with As-contaminated water, and their effect on the uptake and accumulation of the contaminant in the plant roots and leaves, were studied. Accumulation of this non-essential element occurred mainly into the root system and reduced both biomass development and net photosynthesis rate (while altering the plant P status). Plant growth-promoting fungi (PGPF) of both Trichoderma species alleviated, at least in part, the phytotoxicity of As, essentially by decreasing its accumulation in the tissues and enhancing plant growth, P status and net photosynthesis rate. Our results indicate that inoculation of lettuce with selected Trichoderma strains may be helpful, beside the classical biocontrol application, in alleviating abiotic stresses such as that caused by irrigation with As-contaminated water, and in reducing the concentration of this metalloid in the edible part of the plant.     

Inhibition of MMP-2 but not MMP-9 Influences Inner Ear Spiral Ganglion Neurons In Vitro

Matrix metalloproteinases (MMPs) play an important role in modeling of the extracellular matrix. There is increasing evidence that these proteases are important in neurite elongation and axonal guidance during development in the central nervous system and retina. Moreover, they are also expressed after acute injury and can be the key mediators of pathogenesis. However, the role of MMPs in the inner ear is largely unknown. Our group recently demonstrated that general inhibition of MMPs resulted in auditory hair cell loss in vitro. In the present study, we investigated the role of MMPs in inner ear spiral ganglion neuron (SGN) survival, neuritogenesis and neurite extension by blocking MMPs known to be involved in axonal guidance, neurite elongation, and apoptosis in other neuronal systems. Spiral ganglion (SG) explants from 5-day-old Wistar rats were treated with different concentrations of the general MMP inhibitor GM6001, a specific MMP-2 inhibitor, and a specific MMP-9 inhibitor, in vitro. The general inhibitor of MMPs and the specific inhibition of MMP-2 significantly reduced both the number of neurites that extended from SG explants, as well as the length of individual neurites. However, neither the general inhibitor of MMPs nor the specific inhibition of MMP-2 influenced SGN survival. Inhibition of MMP-9 had no influence on SGNs. The data suggest that MMPs, and more specifically MMP-2, influence the growth of developing afferent neurites in the mammalian inner ear in vivo.