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The peroxisome proliferator-activated receptor-gamma (PPARgamma) high-affinity ligand, 15-deoxy-Delta-12,14-PGJ(2) (15d-PGJ(2)), is toxic to malignant cells through cell cycle arrest and apoptosis induction. In this study, we investigated the effects of 15d-PGJ(2) on apoptosis induction and expression of apoptosis-related proteins in hepatocellular carcinoma (HCC) cells. 15d-PGJ(2) induced apoptosis in SK-Hep1 and HepG2 cells at a 50 micro M concentration. Pretreatment with the pan-caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp (OMe) fluoromethyl ketone (2-VAD-fmk), only partially blocked apoptosis induced by 40 micro M 15d-PGJ(2). This indicated that 15d-PGJ(2) induction of apoptosis was associated with a caspase-3-independent pathway. 15d-PGJ(2) also induced down-regulation of the X chromosome-linked inhibitor of apoptosis (XIAP), Bclx, and apoptotic protease-activating factor-1 in SK-Hep1 cells but not in HepG2 cells. However, 15d-PGJ(2) sensitized both HCC cell lines to TNF-related apoptosis-induced ligand-induced apoptosis. In SK-Hep1 cells, cell toxicity, nuclear factor-kappaB (NF-kappaB) suppression, and XIAP down-regulation were induced by 15d-PGJ(2) treatment under conditions in which PPARgamma was down-regulated. These results suggest that the effect of 15d-PGJ(2) was through a PPARgamma-independent mechanism. Although cell toxicity was induced when PPARgamma was down-regulated in HepG2 cells, NF-kappaB suppression and XIAP down-regulation were not induced. In conclusion, 15d-PGJ(2) induces apoptosis of HCC cell lines via caspase-dependent and -independent pathways. In SK-Hep1 cells, the ability of 15d-PGJ(2) to induce cell toxicity, NF-kappaB suppression, or XIAP down-regulation seemed to occur via a PPARgamma-independent mechanism, but in HepG2 cells, NF-kappaB suppression by 15d-PGJ(2) was dependent on PPARgamma.

AIM: To detect the expression of a proliferation-related ligand on human hepatocellular carcinoma (HCC) cell lines (SK-Hep1, HLE and HepG2) and in culture medium. METHODS: APRIL expression was analyzed by Western blotting in HCC cell lines. Effects of APRIL to cell count and angiogenesis were analyzed, too. RESULTS: Recombinant human APRIL (rhAPRIL) increased cell viability of HepG2 cells and, in HUVEC, rhAPRIL provided slight tolerance to cell death from serum starvation. Soluble APRIL (sAPRIL) from HLE cells increased after serum starvation, but did not change in SK-Hep1 or HepG2 cells. These cells showed down-regulation of VEGF after incubation with anti-APRIL antibody. Furthermore, culture medium from the HCC cells treated with anti-APRIL antibody treatment inhibited tube formation of HUVECs. CONCLUSION: Functional expression of APRIL might contribute to neovascularization via an upregulation of VEGF in HCC.

PPARgamma is known to induce apoptosis in malignant tumor cells, but the mechanism of this induction is not well understood. We investigated induction of apoptosis with 15-Deoxy-Delta12,14-prostaglandin J2 (15d-PGJ2), a PPARgamma ligand, in cholangio cell carcinoma (CCC) cells (RBE, ETK-1 or HuCCT-1). Apoptosis was induced in RBE and ETK-1 cells with 15d-PGJ2, but not in HuCCT-1 cells, although PPARgamma was expressed in all CCC cells. Apoptosis-related proteins were also expressed, including FLIP, bclx, Apaf-1 and XIAP, but expression levels differed among the three cell lines. RBE cells treated with 15d-PGJ2 showed caspase activation, and it appeared that PPARgamma-induced apoptosis was dependent on caspase activation. However, neither ETK-1 nor HuCCT-1 cells showed significant activation of caspase-8 or -3 with 15d-PGJ2 treatment, raising the possibility of a caspase-independent apoptosis induction pathway. XIAP was down-regulated by 15d-PGJ2 in all three CCC cell lines. Therefore, 15d-PGJ2 induces apoptosis in CCC cells via caspase-dependent or independent pathways. 15d-PGJ2 may also induce down-regulation of XIAP and may promote caspase cascade activation through TNF-family receptor signaling pathways.

Human hepatocellular carcinomas (HCCs) show resistance to apoptosis mediated by several death receptors. Because cellular FLICE/caspase-8-inhibitory protein (cFLIP) is a recently identified intracellular inhibitor of caspase-8 activation that potently inhibits death signaling mediated by all known death receptors, including Fas, TNF-receptor (TNF-R), and TNF-related apoptosis-inducing ligand receptors (TRAIL-Rs), we investigated the expression and function of cFLIP in human HCCs. We found that cFLIP is constitutively expressed in all human HCC cell lines and is expressed more in human HCC tissues than in nontumor liver tissues. Metabolic inhibitors, actinomycin D (ActD) or cycloheximide (CHX), dramatically rendered HCC cells sensitive to Fas-mediated apoptosis. Neither caspase-8 nor caspase-3 was activated by agonistic anti-Fas antibody alone, but both caspases were activated by Fas stimulation in the presence of ActD or CHX, indicating the importance of caspase-8 inhibitors that are sensitive to metabolic inhibitors. Actually, cFLIP expression was decreased in ActD or CHX treatment. cFLIP down-regulation induced by cFLIP antisense oligodeoxynucleotides sensitized HLE cells to Fas, TNF-R, and TRAIL-R-mediated apoptosis. Furthermore, cFLIP over-expression activated nuclear factor (NF)-kappaB and cFLIP down-regulation attenuated NF-kappaB activation induced by TNF-alpha or TRAIL. Pretreatment with pan-caspase-inhibitor, benzyloxycarbonyl-Val-Ala-Asp (OMe) fluoromethyl ketone (Z-VAD-fmk), restored NF-kappaB activity attenuated by cFLIP down-regulation. cFLIP expression was increased by TNF-alpha, TRAIL, or vascular endothelial growth factor but decreased by wortmannin, indicating that cFLIP expression is regulated by both the NF-kappaB and phosphatidylinostiol-3 kinase (PI-3)/Akt pathways. These results suggest that cFLIP plays an important role in cell survival not simply by inhibiting death-receptor-mediated apoptosis but also by regulating NF-kappaB activation in human HCCs.

Currently, pyogenic liver abscess is not frequent, but it is a severe infectious disease. However a strategy for the effective treatment of liver abscess is not established. We analyzed 75 cases of liver abscess over an eight year period and evaluated their prognosis, any associated underlying disease, or the effect of percutaneous transhepatic abscess drainage (PTAD). For all 75 cases, laboratory data were analyzed and imaging studies were performed. Next, PTAD and antibiotic administration were started on these cases as first choice treatments. These treatments were continued until the laboratory data of the patient were restored to within the normal range. Those cases that were PTAD non-effective or required operation for underlying diseases, underwent operations. Of the total 75 cases, 63 survived after treatment and 12 cases died. Bacteria were detected in 50 cases and Klebsiella pneumoniae was detected in 31 of these 50 cases, but 25 out of 75 cases were negative. The biliary system was the main route of infection. PTAD was effective, especially in cases that were complicated with disseminated intravascular coagulation (DIC) or acute renal failure (ARF). PTAD is an effective treatment for liver abscess, it is especially useful in the restoration of severe general conditions as indicated by this study.

To evaluate the clinical utility of serum fibrosis markers, including YKL-40, in patients with HCV-associated liver disease.A total of 109 patients with HCV-associated liver disease were enrolled. We measured serum type IV collagen, amino-terminal peptide of type III procollagen (PIIIP), hyaluronic acid (HA), YKL-40 levels and biochemical. Parameters by RIA or ELISA. Eighty-eight patients underwent liver biopsy, and 67 of 109 patients received interferon (IFN) therapy. We also investigated the relationship between the concentrations of serum fibrosis markers and histological fibrosis scores (METAVIR), and evaluated the changes of the levels of fibrosis markers before and after the IFN therapy.The increase in serum levels of all markers, particularly HA, was correlated with the progression of liver fibrosis (for type IV collagen, F = 9.076, P0.0001; for PIIIP, F = 9.636, P0.0001; for HA, F = 13.128, P0.0001; and for YKL-40, F = 8.016, P0.0001). YKL-40 had strong correlation with HA (r = 0.536, P0.0001). Based on the receiver operating curve (ROC), the ability of serum HA exceeded the abilities of other serum markers to determine fibrosis score 4 from fibrosis score 0-3 (AUC = 0.854). While YKL-40 was superior to other fibrosis markers for predicting severe fibrosis (F2-F4) from mild fibrosis (F0-F1) (YKL-40, AUC = 0.809; HA, AUC = 0.805). After IFN therapy, only YKL-40 values significantly decreased not only in the responder group, but also in the nonresponder group (P = 0.03).YKL-40 may be a useful non-invasive serum marker to estimate the degree of liver fibrosis and to evaluate the efficacy of IFN therapies in patients with HCV-associated liver disease.

To analyze the risk factors of hepatocellular carcinoma (HCC) recurrence after radiofrequency ablation (RFA) treatment with HCV-associated hepatitis.Twenty-six patients with HCV-associated HCC who were followed-up for more than 12 mo were selected for this study. Risk factors for distant intrahepatic recurrences of HCC were evaluated for patients in whom complete coagulation was achieved without recurrence in the same subsegment as the primary nodule. Twelve clinical and tumoral factors were examined: Age, gender, nodule diameter, number of primary HCC nodule, Child-Pugh classification, serum platelet, serum albumin, serum AST, post RFA AST, serum ALT, post RFA ALT, post RFA treatment.Distant recurrences of HCC in remnant liver after RFA were observed in 14 cases and in the number of primary HCC nodules (P = 0.047), and the serum platelets (P = 0.030), the clear difference came out by the recurrence group and the non-recurrence group. The cumulative recurrence rates after 1 and 2 years were 30.8% and 86.8%, respectively for primary multinodular HCC, and 15.4% and 29.5% respectively, for primary uninodular HCC. In addition the 1-year recurrence rates for patients with serum albumin more than 3.4 g/dL and less than 3.4 g/dL were 23.1% for both, but the 2-years recurrence rates were 89.0% and 23.1%, respectively. The number of primary HCC nodules (relative risk, 6.970; P = 0.016) were found to be a statistically significant predictor for poor distant intrahepatic recurrence by univariate analysis.Patients who have multiple HCC nodules, low serum platelets and low serum albumin accompanied by HCV infection, should be carefully followed because of the high incidence of new HCC lesions in the remnant liver, even if coagulation RFA is complete.

Inflammatory pseudotumor (IPT) is a rare benign tumor of unknown origin, it has the appearance of a malignant tumor but has a benign histology and clinical course. Therefore, we studied five patients with IPT of the liver to determine what examination can aid in its diagnosis. Five cases of inflammatory pseudotumor of the liver were analyzed. All patients were examined by echography, computed tomography (CT), magnetic resonance imaging (MRI), endoscopic retrograde cholangiography (ERC) and angiography to diagnose the liver tumor. In all patients echography and CT scan showed a similar appearance while MRI showed a variable pattern. In two patients ERC showed a stenotic image of intra-hepatic bile ducts. In the angiographic study, the arterial phase in three patients showed a hypervascular tumor and in one patient, a hypovascular tumor. Vascular abnormality was presented in one patient. Similarly, portography in four patients showed some abnormality. We performed ultrasonography-guided percutaneous needle biopsy in two patients in order to diagnose IPT. Histological examinations of two patients were consistent with IPT. The other three patients underwent surgical treatment for a cholangiocellular carcinoma or abscess. It is difficult to diagnose IPT of the liver exclusively with an image examination. Ultrasonography-guided percutaneous liver biopsy should be performed in order to diagnose IPT by histology.