Proton pump inhibitor treatment is associated with the severity of liver disease and increased mortality in patients with cirrhosis.

BACKGROUND: Proton pump inhibitors (PPI) are widely used in patients with liver diseases. Within the last years, there have been concerns about the PPI use as they may promote infections in patients with cirrhosis. AIM: As there are sparse data of the prognostic relevance of PPI treatment, to perform a prospective study investigating the relation of PPI treatment and overall survival (OS) in cirrhotic individuals. METHODS: Patients with cirrhosis were enrolled and followed prospectively. The primary end point was OS. PPI treatment and additional clinical and laboratory data were assessed at the day of the study inclusion. The time until the end point death was assessed and the individual risks were calculated with Cox regression analyses. RESULTS: A total of 272 patients were included and 213 individuals (78.3%) were on PPI treatment. In multivariate logistic regression analysis, PPI treatment was associated with higher MELD scores (P = 0.027) and ascites (P = 0.039). In a multivariate Cox regression model, PPI use was an independent predictor of mortality (hazard ratio 2.330, 95% confidence interval 1.264-4.296, P = 0.007) in addition to the model of end-stage liver disease (MELD) score, hepatocellular carcinoma and hepatic decompensation. CONCLUSIONS: PPI use is an independent risk factor for mortality in patients with cirrhosis. Although a causative role for increased mortality in patients taking PPI is still missing, the prescription of PPI in cirrhotics should be considered carefully taking into account its potential adverse effects.

Soluble CD163 is an indicator of liver inflammation and fibrosis in patients chronically infected with the hepatitis B virus.

Soluble CD163 (sCD163), a marker for macrophage activation, was found to be associated with the severity of liver cirrhosis. The aim of the current study was to investigate whether serum sCD163 levels correlate with liver inflammation and fibrosis in patients with chronic hepatitis B virus (HBV) infection. In a retrospective cohort study, serum sCD163 levels were assessed by ELISA together with clinical and laboratory data in 186 patients with chronic HBV infection and 15 healthy controls. The relation between parameters for liver fibrosis and necroinflammation and sCD163 levels was analysed. Additionally, sCD163 was quantified in a subset of follow-up serum samples after initiation of antiviral treatment. sCD163 levels differed among phases of chronic HBV infection (P < 0.0001), and sCD163 concentrations were associated with inflammatory activity and fibrosis in the liver. sCD163 levels ≥ 1961 ng/l had a high specificity in the identification of subjects with substantial fibrosis (F ≥ 2). sCD163 concentrations decreased significantly after initiation of antiviral treatment. The correlation of sCD163 levels with necroinflammation and fibrosis and the sCD163 decline under treatment indicates that macrophage activation plays a role in HBV-related liver pathogenesis.

Severe 25-hydroxyvitamin D deficiency identifies a poor prognosis in patients with hepatocellular carcinoma - a prospective cohort study.

BACKGROUND: Vitamin D is involved in many biological processes. The role of vitamin D in patients with hepatocellular carcinoma (HCC) remains inconclusive, although there is evolving evidence that vitamin D may modulate cancer development and progression. AIM: To evaluate serum vitamin D as prognostic parameter in HCC, we performed a prospective cohort study. METHODS: HCC patients were prospectively recruited and 25-hydroxyvitamin D3 (25(OH)D3 ) levels were determined. 25(OH)D3 levels were compared to stages of cirrhosis and HCC stages with nonparametric Kruskal-Wallis tests and Spearman correlations in 200 HCC patients. The association of the 25(OH)D3 levels and overall survival (OS) was assessed in uni- and multivariate Cox regression models. RESULTS: Two-hundred patients with HCC were included. The mean follow-up time was 322 ± 342 days with a range of 1-1508 days. Nineteen patients underwent liver transplantation and 60 patients died within the observation time. The mean serum 25(OH)D3 concentration was 17 ± 13 ng/mL with a range of 1-72 ng/mL. 25(OH)D3 serum levels negatively correlated with the stage of cirrhosis as well as with stages of HCC. Patients with severe 25(OH)D3 deficiency had the highest mortality risk (hazard ratio 2.225, 95% confidence interval 1.331-3.719, P = 0.002). Furthermore, very low 25(OH)D3 levels were associated with mortality independently from the MELD score and high alpha-Fetoprotein levels (>400 ng/mL) in a multivariate Cox regression model. CONCLUSIONS: We conclude that 25(OH)D3 deficiency is associated with advanced stages of hepatocellular carcinoma and it is a prognostic indicator for a poor outcome.

Serum microRNA-122 kinetics in patients with chronic hepatitis C virus infection during antiviral therapy.

The levels of the liver-specific microRNA-122 (miR-122) circulating extracellularly in the blood have been shown to be increased upon liver damage. However, it is unknown if the levels of serum miR-122 are altered during antiviral therapy and reflect the therapeutic success. Here, we investigated miR-122 serum levels in patients with chronic hepatitis C virus (HCV) genotype 1 infection during antiviral therapy with pegylated interferon and ribavirin. Therefore, sera from 60 patients with chronic HCV infection genotype 1 showing sustained virological response (SVR), non-response or relapse to therapy obtained at baseline, 4, 12, 24 weeks, end of treatment and follow-up were analysed retrospectively for miR-122 content by quantitative real-time reverse transcription PCR. The time courses of miR-122 were correlated with HCV RNA as well as standard liver parameters. We found that while there was no relation between serum miR-122 and HCV RNA levels at baseline, the decline in HCV RNA upon beginning of the therapy closely correlated with the reduction of serum miR-122 in the three different patient groups. Moreover, the serum miR-122 level correlated well with alanine aminotransaminase, a marker of ongoing liver damage. At follow-up serum miR-122 levels remained low in SVR, but increased to baseline levels in patients not responding or showing relapse to therapy. In contrast, the serum concentration of the ubiquitously expressed miR-16 did not change during therapy. We conclude that the serum level of miR-122 well reflects the success of interferon/ribavirin therapy in patients with chronic HCV infection.

Dysregulation of global microRNA expression in splenic marginal zone lymphoma and influence of chronic hepatitis C virus infection.

The precise molecular pathogenesis of splenic marginal zone lymphoma (SMZL) is still unknown. Clinical and epidemiological data suggest that chronic hepatitis C virus (HCV) infection may have an etiological role in a subset of cases.We performed a large-scale microRNA (miRNA) expression profiling analysis of 381 miRNAs by quantitative reverse transcription PCR (Q-RT-PCR) of 26 microdissected splenic tissue samples (7 HCV(+) SMZL; 8 HCV(-) SMZL and 11 non-neoplastic splenic controls). Single assay Q-RT-PCR and miRNA in situ hybridization (miRNA-ISH) were used to confirm the results in an independent cohort. Unsupervised hierarchical clustering of miRNA expression profiles demonstrated a distinct signature of SMZL compared with the normal splenic marginal zone. Supervised analysis revealed differentially expressed miRNAs, including miRNAs with previously recognized tumor suppressive or oncogenic potential. Five miRNAs were found significantly overexpressed in SMZL, including miR-21, miR-155 and miR-146a, whereas seven miRNAs showed significantly reduced expression, including miR-139, miR-345, miR-125a and miR-126. Furthermore, we identified miR-26b, a miRNA known to have tumor suppressive properties, as significantly downregulated in SMZL arising in HCV-positive patients (P=0.0016). In conclusion, there is a characteristic dysregulation of miRNA expression in SMZL with a possible implication in its molecular tumorigenesis.

Serum microRNA-122 levels in different groups of patients with chronic hepatitis B virus infection.

miR-122 is a liver-specific microRNA, which also circulates in the blood. The levels of miR-122 in serum and plasma correlate with hepatic necroinflammation in patients with hepatitis B virus (HBV) infection. Here, we investigated whether miR-122 levels correlate with surrogate markers for viral replication and translation. Furthermore, we examined whether miR-122 levels differ in the different groups of HBV-infected patients and whether miR-122 levels may be useful to identify patients with higher or lower risk for liver disease progression. Therefore, RNA was extracted from sera of therapy-naïve patients with HBV infection (n = 89) and from healthy volunteers (n = 19). The concentration of miR-122 was assessed by quantitative real-time reverse-transcription PCR. HBs antigen and HBV DNA levels were quantified as surrogate parameters for HBV replication and translation. Liver biopsies were examined according to the histological activity index and the degree of fibrosis was assessed. We found that the miR-122 serum concentration correlated with the level of ALT, HBV DNA and HBs antigen (r = 0.259, P < 0.05; r = 0.225, P < 0.05; r = 0.508, P < 0.001, respectively). The miR-122 serum levels discriminated the different patient groups infected with HBV from healthy subjects (P < 0.001), and inactive carrier patients with high (>3500 IU/mL) or low (<3500 IU/mL) levels of HBs antigen could be differentiated by the miR-122 serum concentration (P < 0.05). As serum miR-122 levels strongly correlated with HBs antigen, it might be an indicator for viral translation. Furthermore, serum miR-122 levels discriminated HBV carrier patients with high or low risk for disease progression and may, thus, be an additional marker for risk stratification.

Comparison of envelope 2 CD81 binding regions in PBMC-derived versus serum-derived hepatitis C virus isolates: higher conservation of CD81 region 2 in PBMC isolates.

UNLABELLED: The aim of the present study was to investigate the variability of hepatitis C virus (HCV) CD81 binding regions (CD81-1/2) in peripheral blood mononuclear cells (PBMC)-derived and serum-derived HCV-RNA samples. HCV-RNA was isolated from PBMC (104 cells) and serum samples from 37 patients chronically infected with HCV genotype 1a/1b (n=21/16). The hypervariable regions 1/2 (amino acid 384-410, amino acid 474-482) and regions CD81-1/2 (amino acid 474-494, amino acid 522-551) were analysed. Mutational frequency of amino acid sequences was compared between PBMC-derived and serum-derived HCV variants as well as local accumulation of mutations. Furthermore, CD81 was quantified on PBMC. Mutational frequency was not different between PBMC-derived and serum-derived HCV variants. A trend to lower mutational frequency in genotype 1a PBMC variants compared with serum-derived variants was observed in region CD81-2 (5%vs 10%). Smoothed mutational frequency analysis showed a significantly lower variability within genotype 1a CD81-2 in PBMC-derived compared to serum-derived HCV-RNA (P=0.026). CD81 expression on PBMC was not correlated with the number of mutations within the CD81 binding regions. CONCLUSION: A higher conservation was observed in region CD81-2 in PBMC-derived versus serum-derived HCV-RNA indicating selection of HCV variants on PBMC. The variability in the CD81 binding regions appeared to be independent from CD81 expression.

Apoptotic cytokeratin 18 neoepitopes in serum of patients with chronic hepatitis C.

In patients with chronic hepatitis C, alanine aminotransferase (ALT) levels do not accurately reflect the extent of liver inflammation. The discrepancy between ALT level and liver damage could be related to the mode of cell death. In the present study, we quantified serum levels of apoptotic cytokeratin 18 (CK-18) neoepitopes that are generated by activated caspases during apoptosis. Apoptotic CK-18 neoepitopes were quantified by enzyme linked immunosorbent assay in sera from patients with chronic hepatitis C and elevated ALT levels (n = 72), patients with chronic hepatitis C and persistently normal ALT levels (n = 27) and healthy controls (n = 19). Serum CK-18 neoepitope levels were strongly correlated with ALT (r = 0.659, P < 0.0001) and the histology activity index (r = 0.374, P < 0.001). Patients with chronic hepatitis C and persistently normal ALT levels had higher apoptotic CK-18 neoepitope levels than healthy controls (P = 0.03) but lower levels than patients with chronic hepatitis C and elevated ALT levels (P < 0.001). Highest serum CK-18 neoepitope levels were observed in patients with cirrhosis (P = 0.002). Hence apoptotic CK-18 neoepitopes in serum of patients with chronic hepatitis C are associated with ALT level and histological liver damage. Serum apoptotic CK-18 neoepitope levels are elevated both in patients with chronic hepatitis C and elevated ALT levels as well as in patients with normal ALT levels indicating that also patients with chronic hepatitis C and normal ALT have an increased hepatocyte loss by apoptosis.

Receptor tyrosine kinases are signaling intermediates of G protein-coupled receptors.

G protein-coupled receptors (GPCRs) can utilize receptor tyrosine kinases (RTKs) to mediate important cellular responses such as proliferation, differentiation and survival. Recent advances in the field suggest that GPCR-induced transactivation of RTKs might be important for diseases such as cancer and cardiac hypertrophy. Depending on the receptor and cell type, GPCR signaling involves activation of several different RTKs. By activating different subsets of RTKs, GPCRs can fine-tune their effects on target cells. Furthermore, RTK-independent signaling pathways also initiated by GPCRs may modify the biological read out of the transactivated RTKs. This review focuses on the mechanisms how GPCRs and intracellular messengers elicit transactivation of different RTKs and the resulting different biological responses.

Mutations in the putative HCV-E2 CD81 binding regions and correlation with cell surface CD81 expression.

The hepatitis C virus (HCV) envelope (E)2 protein interacts with the cellular receptor CD81 leading to modulation of B and T cell function. Recently, a higher binding affinity of subtype 1a in comparison with 1b derived E2 proteins for CD81 in vitro was described. The importance of mutations within the putative CD81 binding regions of different HCV geno-/subtypes in correlation with CD81 expression is unknown. In the present study, CD81 expression on blood lymphocytes of patients with chronic hepatitis C infected with different HCV geno-/subtypes were analysed by fluorescence activated cell sorter analyses. In addition, the putative CD81 binding regions on the E2 gene comprising the hypervariable region (HVR)2 were analysed by direct sequencing. CD81 expression on CD8(+) T-lymphocytes from patients infected with subtype 1a (n = 6) was significantly higher in comparison with subtype 1b (n = 12) and 3 (n = 5) infected patients before and during antiviral therapy (P = 0.006; P = 0.021, respectively). Sequencing of the putative CD81 binding regions in the E2 protein comprising the HVR2 (codon 474-495 and 522-552 according to the HCV-1a prototype HCV-H) showed a highly conserved motif within HVR2 for subtype 1a isolates and an overall low number of mutations within the putative CD81 binding regions, whereas numerous mutations were detected for subtype 1b isolates (12.0 vs 23.6%). HCV-3 isolates showed an intermediate number of mutations within the putative binding sites (19.2%; P = 0.022). In conclusion, the highly conserved sequence within HVR2 and putative CD81 binding sites of subtype 1a isolates previously associated with a high CD81 binding affinity in vitro is correlated with high CD81 expression on CD8(+) T-lymphocytes in vivo.

Electroporation of subcutaneous mouse tumors by rectangular and trapezium high voltage pulses.

The artificial electrotransfer of bioactive agents such as drugs, peptides or therapeutical nucleic acids and oligonucleotides by membrane electroporation (MEP) into single cells and tissue cells requires knowledge of the optimum ranges of the voltage, pulse duration and frequency of the applied pulses. For clinical use, the classical electroporators appear to necessitate some tissue specific presetting of the pulse parameters at the high voltage generator, before the actual therapeutic pulsing is applied. The optimum pulse parameters may be derived from the kinetic normal mode analysis of the current relaxations due to a voltage step (rectangular pulse). Here, the novel method of trapezium test pulses is proposed to rapidly assess the current (I)/voltage (U) characteristics (IUC). The analysis yields practical values for the voltage U(app) between a given electrode distance and pulse duration t(E) of rectangular high voltage (HV) pulses, to be preset for an effective in vivo electroporation of mouse subcutaneous tumors, clamped between two planar plate electrodes of stainless steel. The IUC of the trapezium pulse compares well with the IUC of rectangular pulses of increasing amplitudes. The trapezium pulse phase (s) of constant voltage and 3 ms duration, following the rising ramp phase (r), yields a current relaxation which is similar to the current relaxation during a rectangular pulse of similar duration. The fit of the current relaxation of the trapezium phase (s) to an exponential function and the IUC can be used to estimate the maximum current at a given voltage. The IUC of the falling edge (phase f) of the trapezium pulse serves to estimate the minimum voltage for the exploration of the long-lived electroporation membrane states with consecutive low-voltage (LV) pulses of longer duration, to eventually enhance electrophoretic uptake of ionic substances, initiated by the preceding HV pulses.

Coupling of endothelin receptors to the ERK/MAP kinase pathway. Roles of palmitoylation and G(alpha)q.

Endothelins are potent mitogens that stimulate extracellular signal-regulated kinases (ERK/MAP kinases) through their cognate G-protein-coupled receptors, ET(A) and ET(B). To address the role of post-translational ET receptor modifications such as acylation on ERK activation and to identify relevant downstream effectors coupling the ET receptor to the ERK signaling cascades we have constructed a panel of palmitoylation-deficient ET receptor mutants with differential G(alpha) protein binding capacity. Endothelin-1 stimulation of wild-type ET(A) or ET(B) induced a fivefold to sixfold increase in ERK in COS-7 and CHO cells whereas full-length nonpalmitoylated ET(A) and ET(B) mutants failed to stimulate ERK. A truncated ET(B) lacking the C-terminal tail domain including putative phosphorylation and arrestin binding site(s) but retaining the critical palmitoylation site(s) was still able to fully stimulate ERK activation. Using mutated ET receptors with selective G-protein-coupling we found that endothelin-induced stimulation of G(alpha)q, but not of G(alpha)i or G(alpha)s, is essential for endothelin-mediated ERK activation. Inhibition of protein kinases A and C or epidermal growth factor receptor kinase failed to prevent ET(A)- and ET(B)-mediated ERK activation whereas blockage of phospholipase C-beta completely abrogated endothelin-promoted ERK activation through ET(A) and ET(B) in recombinant COS-7 and native C6 cells. Complex formation of Ca2+ or inhibition of Src family tyrosine kinases prevented ET-1-induced ERK-2 activation in C6-cells. Our results indicate that endothelin-promoted ERK/MAPK activation criticially depends on palmitoylation but not on phosphorylation of ET receptors, and that the G(alpha)q/phospholipase C-beta/Ca2+/Src signaling cascade is necessary for efficient coupling of ET receptors to the ERK/MAPK pathway.

Subcellular distribution and function of Rab3A-D in pancreatic acinar AR42J cells.

Members of the Rab3 subfamily have been linked to the regulation of exocytosis in secretory cells. We have recently shown by Northern blot analysis that pancreatic acinar-like AR42J cells express all four Rab3 isoforms (Rab3A-D). In the present study, we examined the subcellular distribution of endogenously expressed Rab3 proteins and their relation to the amylase-containing secretory compartment in dexamethasone-differentiated AR42J cells. Rab3A and Rab3C were enriched in the cytosol, Rab3B and Rab3D in the membrane fraction. Accordingly, confocal immunocytochemistry revealed that Rab3B and Rab3D were located in a compartment close to the plasma membrane, whereas anti-Rab3A and Rab3C mainly stained the cytosol. Sucrose density gradient centrifugation showed overlapping, but distinct localization of each Rab3 isoform. The order of banding from lighter to more dense fractions was Rab3C < Rab3A < Rab3B < Rab3D. All Rab3 proteins at least partially colocalized with amylase immunoreactivity. Transient overexpression of Rab3 proteins showed that Rab3A inhibited cholecystokinin (CCK)-induced amylase secretion, whereas overexpression of other Rab3 isoforms had no significant effect. In conclusion, our data indicate that the different Rab3 proteins show distinct subcellular distribution, suggesting different impact on exocrine secretory response in dexamethasone-differentiated AR42J cells.

Interferon alfa down-regulates CD81 in patients with chronic hepatitis C.

CD81 protein has been shown to bind hepatitis C virus (HCV) envelope 2 (E2) glycoprotein in vitro and may act as a (co)receptor for HCV. Regulation of CD81 expression by interferon alfa (IFN-alpha) and ribavirin could thereby affect the response to antiviral therapy. In the present study, the effects of IFN-alpha and ribavirin on CD81 protein and CD81 mRNA were assessed in peripheral blood lymphocytes (PBL) and isolated human hepatocytes by fluorescence-activated cell sorter (FACS) analysis and real-time polymerase chain reaction (PCR), respectively. In addition, regulation of CD81 in PBL was investigated in 10 patients treated with combination therapy. Incubation with IFN-alpha (50 U/mL) down-regulated total CD81 in PBL (81.7 +/- 11.6% of control; P =.003) and in isolated human hepatocytes (91.6 +/- 8.1% of control; P =.034). Incubation with IFN-alpha with and without ribavirin (2.2 microg/mL) significantly reduced cell surface-associated CD81 protein (83.9 +/- 10.3% of control; P =.003). PBL of untreated patients chronically infected with HCV had significantly higher levels of total CD81 protein compared with PBL obtained from healthy donors (631.1 +/- 93.3 vs. 538.9 +/- 95.2 relative fluorescence units [RFU]; P =.030). Pretreatment cell surface-associated CD81 protein was lower in patients infected with genotype HCV-3 than those infected with HCV-1 (111.8 +/- 15.0 vs. 162.0 +/- 41.3 RFU; P =.019). Furthermore, cell surface-associated CD81 protein was lower 4 weeks after initiation of therapy in patients with an initial virologic response compared with initial virologic nonresponders (110.5 +/- 8.5 vs. 139.8 +/- 27.5 RFU; P =.057). In conclusion, IFN-alpha and ribavirin regulate CD81 expression in vitro and in vivo. CD81 expression correlates with HCV genotype and initial virologic response in patients with chronic hepatitis C.

Pertussis toxin inhibits cholecystokinin- and epidermal growth factor-induced mitogen-activated protein kinase activation by disinhibition of the cAMP signaling pathway and inhibition of c-Raf-1.

Pertussis toxin (PTx), which inactivates G(i/o) type G proteins, is widely used to investigate the involvement of G(i/o) proteins in signal transduction. Activation of extracellular-regulated kinases 1 and 2 (ERK1/2) by G protein-coupled receptors has been described to occur either through a PTx-insensitive pathway involving activation of phospholipase C and protein kinase C (PKC), or through a PTx-sensitive pathway involving G(i)betagamma-mediated activation of Src. Cholecystokinin (CCK) activates ERK1/2 by a PKC-dependent, and thus presumably PTx-insensitive, pathway. However, CCK has recently been shown to induce activation of G(i) proteins in addition to G(q/11). In the present study, PTx partially inhibited CCK-induced ERK1/2 activation in pancreatic AR42J cells, although activation of phospholipase C was not reduced. PTx also inhibited ERK1/2 activation in response to the PKC activator 12-O-tetradecanoylphorbol-13-acetate (TPA) and epidermal growth factor (EGF) as well as activation of c-Raf-1 by EGF and CCK. In contrast, PTx, CCK, and EGF had only minor effects on A-Raf and B-Raf activity. Forskolin, a direct activator of adenylyl cyclase, inhibited CCK- and EGF-induced activation of c-Raf-1 and ERK1/2 in a manner similar to that of PTx. In PTx-treated cells, the cAMP content was increased and forskolin did not further inhibit CCK- and EGF-induced activation of c-Raf-1 or ERK1/2. In conclusion, the present study shows that PTx-sensitivity of receptor-induced ERK1/2 activation could be a consequence of disinhibition of the adenylyl cyclase signaling pathway, which in turn causes inhibition of c-Raf-1 activation rather than indicating involvement of a PTx-sensitive G protein in this signaling pathway.

Involvement of the platelet-derived growth factor receptor in angiotensin II-induced activation of extracellular regulated kinases 1 and 2 in human mesangial cells.

In mesangial cells angiotensin II (Ang II) has been shown to activate extracellular regulated kinases 1 and 2 (ERK1/2). Here, we studied the role of the epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor (PDGFR) in Ang II-induced ERK1/2 activation in human mesangial cells. Ang II induced activation of ERK1/2 via the AT(1) receptor, and this response was blocked by the PDGFR-selective tyrosine kinase inhibitor AG1295, but not by AG1478, an EGFR-selective tyrosine kinase inhibitor, indicating participation of the PDGFR, but not of the EGFR in Ang II-induced ERK1/2 activation. In agreement with this assumption, Ang II caused tyrosine phosphorylation of the PDGFR and the adapter protein Shc in an AG1295-sensitive fashion. In conclusion, our data show that Ang II-induced activation of mitogenic signalling cascade in human mesangial cells involves ligand-independent activation of the PDGFR, but not of the coexpressed EGFR.

Polo-like kinase1, a new target for antisense tumor therapy.

The Polo-like kinase 1 (Plk1) is a highly conserved mitotic serine/threonine kinase which is commonly overexpressed in cancer cell lines. Plk1 positively regulates mitotic progression by activating the CDC25C-CDK1 amplification loop and by regulating late mitotic events, primarily the ubiquitin-dependent proteolysis. In the present study, an antisense strategy against Plk1 mRNA was developed to specifically inhibit cell proliferation of cancer cells in cell culture and in the nude-mouse tumor model. Among 41 phosphorothioate antisense oligodeoxynucleotides tested, the 20-mer JWG2000 strongly inhibited expression of Plk1 in cultured A549 cells, leading to loss of cell viability, and exhibited anti-tumor activity in nude mice A549 xenograft. JWG2000 did not inhibit growth and viability of primary human mesangial cells and human amnion fibroblasts.