ABSTRACT
Replacement of the native promoter of theglobal regulator LaeA-like gene of Daldinia eschscholzii by a strong gpdA promoter led to the generation of two novel cyclopentenone metabolites, named dalestones A and B, whose structures were assigned by a combination of spectroscopic analysis, modified Mosher's reaction, and electronic circular dichroism (ECD). Dalestones A and B inhibit the gene expression of TNF-α and IL-6 in LPS-induced RAW264.7 macrophages.
ABSTRACT
OBJECTIVE: To evaluate the effect of protein kinase inhibitor on luteolin glucuronidation. METHODS: LS174T cells were treated with either curcumin or calphostin C of various concentrations. The glucuronidation metabolites of luteolin, catalyzed by the S9 of treated LS174T cells, was measured by HPL C. The expression of UGT1A in treated LS174T cells was determined by realtime PCR and western blot. RESULTS: A rapid down-regulation of luteolin glucuronidation catalyzed by LS174T cells following curcumin and calphostin C treatment was observed. However, there was no effect on the expression of UGT1A in treated LS174T cells. CONCLUSION: The glucuronidation of luteolin can be suppressed by protein kinase inhibitor indirectly. The suppression may be caused by abnormal phosphorylation of UGTs, which are catalyzed by protein kinase.
ABSTRACT
<p><b>OBJECTIVE</b>To examine how the thymidine phosphorylase (TP) gene expression is upregulated by interferon-alpha (IFN-alpha) in human hepatocellular carcinoma SMMC-7721 cells.</p><p><b>METHODS</b>TP mRNA levels were determined by RT-PCR. Whether the JAK-STAT cascade mediates IFN-alpha-induced TP mRNA expression was studied by pretreatment with Janus Kinase (JAK) inhibitor, AG-490. Effects of IFN-alpha on TP mRNA stability were detected with additional actinomycin D.</p><p><b>RESULTS</b>The expression of TP mRNA was induced by IFN-alpha in a dose- and time-dependent manner in SMMC-7721 (human hepatocellular carcinoma) cells. TP mRNA levels rose at 8 h, reached the peak value at 12 h, and remained at a high level up to 72 h in SMMC-7721 cells treated with IFN-alpha 10000 U/ml. IFN-alpha at a dose of 5000 or 10000 U/ml up-regulated TP expression about 3 fold compared with that of non-treated cells (P < 0.05). Induction of TP mRNA expression by IFN-alpha was significantly inhibited in SMMC-7721 cells by pretreatment with AG-490, in comparison with that treated with IFN-alpha alone. Pretreatment of SMMC-7721 cells with IFN-alpha 10000 U/ml for 24 h caused a substantial stabilization of TP mRNA, with a half-live of 35.8 h, compared with 8.5 hr in the control SMMC-7721 cells.</p><p><b>CONCLUSION</b>IFN-alpha at certain doses upregulates TP mRNA expression via both JAK-STAT transcriptional activation and post-transcriptional mRNA stabilization in human hepatocellular carcinoma SMMC-7721 cells.</p>
Subject(s)
Humans , Carcinoma, Hepatocellular , Pathology , Cell Line, Tumor , Dose-Response Relationship, Drug , Enzyme Inhibitors , Pharmacology , Gene Expression Regulation, Neoplastic , Interferon-alpha , Pharmacology , Janus Kinases , Metabolism , Liver Neoplasms , Pathology , RNA, Messenger , Metabolism , STAT1 Transcription Factor , Metabolism , Thymidine Phosphorylase , Genetics , Transcriptional Activation , Tyrphostins , PharmacologyABSTRACT
<p><b>BACKGROUND</b>Selection of patients with hepatocellular carcinoma (HCC) for orthotopic liver transplantation (OLT) remains controversial. Since there is a trend to expand the transplant criteria for HCC patients, we reviewed the data of patients with HCC who had received OLT at our institute to determine their survival and prognostic factors.</p><p><b>METHODS</b>A total of 67 patients with HCC who had undergone OLT from April 2001 through December 2003 were reviewed retrospectively. Selection OLT candidates with HCC was dependent on the anatomical characteristics and/or the severity of underlying liver cirrhosis. The 67 patients were followed up for more than 6 months after transplantation. Their survival rate was calculated by the Kaplan-Meier method. Univariate and multivariate analyses using the Cox proportional hazards regression model were performed to reveal the factors affecting the survival rate.</p><p><b>RESULTS</b>No perioperative death occurred in this series. The 1- and 2-year cumulative survival rates were 90.0% and 65.6%, and the disease-free survival (DFS) rates were 77.5% and 62.5% respectively. Univariate analysis revealed the tumor size, portal vein tumor thrombus (PVTT), serum alpha-fetoprotein level, bilobular distribution of tumors, pTNM stage and histological differentiation were statistically significant factors affecting the DFS (P < 0.05). Multivariate analysis showed tumor size and PVTT were independent and statistically significant factors affecting the DFS (P = 0.005 and 0.010, respectively). In this series, all but 2 received systemic chemotherapy, among them 13 had tumor recurrence within 8 months after OLT.</p><p><b>CONCLUSIONS</b>OLT is indicated for patients with HCC, even for some patients with end-stage liver disease who may survive longer without tumor recurrence. Adjuvant chemotherapy may decrease the recurrence of HCC after OLT.</p>