Ubon Cha'on

Opisthorchis viverrini-antigen induces expression of MARCKS during inflammation-associated cholangiocarcinogenesis

Myristoylated alanine rich C kinase substrate (MARCKS) has been implicated in PKC-mediated membrane-cytoskeleton alterations that underlie lipopolysaccharide (LPS)-induced macrophage responses. MARCKS is postulated to be involved in inflammation-associated CCA based on its overexpression in cholangiocarcinoma (CCA) and inflammatory cells. The aims of this study were to investigate localization patterns of MARCKS in hamster and human tissue during cholangiocarcinogenesis and to examine the involvement of MARCKS in inflammation. MARCKS protein expression was found prominently in inflammatory cells of Opisthorchis viverrini-treated as well as O. viverrini plus N-nitrosodimethylamine (NDMA)-treated hamsters from week 2 to week 3 of treatment. The positive signal decreased during week 4 to week 12, then increased again at week 26 when CCA developed. At the last time point the expression of MARCKS was observed in both cancer and inflammatory cells. MARCKS protein expression was also found in inflammatory cells, including macrophages in human CCA tissues. O. viverrini excretory/secretory products or worm antigen induced MARCKS mRNA and protein expression in a dose- and time-dependent manner in the human U937 macrophage cell line. The relative mRNA expression of MARCKS in white blood cells of O. viverrini-infected patients was significantly higher than in healthy subjects (P = 0.02). Thus, MARCKS is significantly expressed in macrophages and plays a role in inflammation-related CCA induced by O. viverrini.

Improve discrimination power of serum markers for diagnosis of cholangiocarcinoma using data mining-based approach

OBJECTIVE Cholangiocarcinoma (CCA) is usually fatal because of the absence of tests for early detection and lack of effective therapy. Tumor markers with adequate diagnostic values are of clinical significance. This study is aimed to improve the diagnostic power of serum markers using the computational data mining technique to develop a combined diagnostic model that yielded the best diagnostic values for CCA. DESIGN AND METHODS Eight CCA-associated markers-carcinoembryonic antigen, carbohydrate antigen 19-9, alkaline phosphatase (ALP), and gamma glutamyl transferase, biliary-ALP, mucin5AC, CCA-associated carbohydrate antigen (CCA-CA) and CA-S27-were used as the inputs for the C4.5 decision tree classification model and the selected model was confirmed by ANN analyses. Eight serum markers for CCA were determined in the training set of 85 histologically proven-CCA patients and 82 control subjects. The chosen set of combined markers that gave the best diagnostic values for CCA was then validated in the testing set of 22 CCA patients and 60 controls. RESULTS A decision tree diagram built by the C4.5 algorithm suggested the serial analysis of CCA-CA and ALP for distinguishing CCA patients from non-CCA subjects with all diagnostic parameters ≥95%. The combined tests showed a precise diagnosis in the testing set. CONCLUSIONS The C4.5 model indicates the combined markers of CCA-CA and ALP that produced the more precise diagnosis for CCA.

Overexpression of lactate dehydrogenase A in cholangiocarcinoma is correlated with poor prognosis

Lactate dehydrogenase A (LDHA), a key metabolic enzyme, plays a crucial role in the final step of anaerobic glycolysis. Overexpression of LDHA is observed in many human malignancies in association with tumor progression. The purpose of this study was to investigate LDHA expression pattern during carcinogenesis, its clinico-pathological association, and evaluate the prognostic value of LDHA in CCA patients. LDHA expression was investigated using immunohistochemistry technique in both hamster- (n=60) and human-CCA tissues (n=82). Plasma LDH from healthy control (n=40) and CCA patients (n=29) were determined using an enzymatic based assay. The association of LDHA expression with clinico-pathological findings and prognostic value were evaluated by statistical analysis. In the CCA hamster model, an increase of LDHA expression was associated with the progression of CCA-genesis. Higher LDHA overexpression was associated with shorter survival of CCA patients. Multivariate analysis indicated that LDHA expression including histological type and N stage of tumor were independent prognostic risk factor of patients survival. However, there was no difference in plasma LDH level between CCA patients and healthy controls. LDHA expression is involved in cholangiocarcinogenesis. Overexpression of LDHA can be a marker of poor prognosis in CCA patients and it might be a potential target for CCA treatment.

Alteration of Drug Kinetics in Rats following Exposure to Trichloroethylene

The effect of trichloroethylene (TCY) was investigated to determine whether repeated exposure alters the pharmacokinetics of some drugs. Sprague-Dawley rats were given intraperitoneal injections of TCY (5 mmol/kg) in corn oil once daily for 3 days, while the control group received only corn oil. Four hours after the last dose, theophylline, quinidine, or pentobarbital were administered. Blood samples were collected at appropriate intervals for drug analyses. There was a small decrease in plasma clearance of theophylline, with no change in volume of distribution (Vd) as compared with controls. For quinidine, the elimination half-life was unchanged, and the Vd was decreased by 40%. The clearance of pentobarbital was decreased by 40% in male rats, but not in the females. Nonetheless, the duration of the sleeping time for both sexes was remarkably prolonged as compared with the control group. There was a decrease in the cytochrome P-450 content only in male rats. In conclusion, exposure to TCY causes changes in some drug kinetics, probably resulting from differential effects on the drug-metabolizing enzymes.

Clinical significance of GalNAcylated glycans in cholangiocarcinoma: Values for diagnosis and prognosis

Cancer cells exhibited the aberrant cancer-associated glycans that are potential biomarkers for diagnosis and monitoring of the cancer. In this study, Sophora japonica agglutinin (SJA) was used to detect SJA-specific N-acetylgalactosamine-associated glycans (SNAG) in liver tissues and sera from cholangiocarcinoma (CCA) patients. Whether SNAG could be the diagnostic and prognostic markers for CCA was evaluated. SJA-histochemistry revealed that SNAG was undetec2 in normal bile ducts but was highly expressed in hyperplastic/dysplastic bile ducts and CCA. SNAG was negative in hepatocytes and hepatoma tissues indicating SNAG as a differential marker of CCA and hepatoma. SJA-histochemistry of CCA hamster tissues revealed the involvement of SNAG in the early pathogenesis of bile duct epithelia and CCA development. A SJA-based ELISA was successfully developed to determine SNAG in serum. Serum-SNAG from CCA patients was significantly higher than those of non-CCA control groups with the diagnostic values of 59.5% sensitivity and 73.6% specificity, comparable to those of serum CA19-9. High levels of serum SNAG (≥69AU/ml) indicated poor survival of CCA patients. Taken together, SNAG was first demonstrated here to be a glycobiomarker for diagnosis and prognosis of CCA. Association of SNAG with pathogenesis of bile ducts and CCA development were suggested. (198).