- Email: [email protected]
347 HIGH PTK7 EXPRESSION WAS ASSOCIATED WITH INVASIVENESS OF CHOLANGIOCARCINOMA
POSTERS account for 6% of PCLD patients and the molecular mechanism involved in cyst formation in these patients remains unclear. As cysts develop through focal growth, we hypothesise that cyst formation in SEC63 mutants requires a somatic second hit. Methods: We obtained liver tissue samples from 3 PCLD patients with a SEC63 germline mutation. We collected cyst-epithelial cells from 52 individual cysts using laser micro dissection. Next, we used sanger sequencing to determine the heterozygosity state in each cyst, and sequenced the complete coding sequence of SEC63 and PRKCSH in 38 cysts Results: We found that LOH of the wild type allele was present in 2% (1/52) of the cysts. The genomic region that was lost included SEC63 exon 6–10 and extended over 6 thousand base pairs. There were no somatic PRKCSH or SEC63 mutations in the 38 cysts that were fully sequenced. Conclusions: Somatic inactivation occurs in cysts from patients with a SEC63 germline mutation and extends over a 6 Kb region. The proportion of LOH appears to be lower compared to PRKCSH mutation carriers. This suggests a lower susceptibility of the SEC63 gene to LOH which could be due to the more centromeric location of this gene compared to PRKCSH. 347 HIGH PTK7 EXPRESSION WAS ASSOCIATED WITH INVASIVENESS OF CHOLANGIOCARCINOMA J. Jin, H.Y. Jung, S.H. Kim, K.B. Lee, J.J. Jang. Department of Pathology, Seoul National University College of Medicine, Seoul, Republic of Korea E-mail: [email protected] Background and Aims: Protein tyrosine kinase-7 (PTK7) is a relatively new member and a pseudokinase without detectable catalytic tyrosine kinase activity of the receptor tyrosine kinase (RTK) superfamily. The expression of PTK7 is up-regulated in many common human cancers, including colon, lung, stomach and acute myeloid leukemia. The aim of this study is to explore the role of PTK7 in cholangiocarcinoma (CCA). Methods: We used a cDNA chip study using a DASL method (cDNA mediated annealing, selection, extension, and ligation) for 26 surgically resected intrahepatic CCAs to search the surrogate genes involving prognosis of CCAs. To explore the functional role of PTK7, we used two CCA cell lines (JCK and Choi-CK). The invasion and wound healing assay was used to examine the invasion and migration ability of cell lines before and after PTK7 silencing by small interference RNA (siRNA). Results: By DASL chip assay, we found an increased PTK7 signal in poor prognosis group (mean log2 (signal value) 12.09 vs 11.48, deceased vs alive group, p = 0.021 by T-test). PTK7 was highly expressed in JCK cells than Choi-CK cells. Moreover, the invasion and migration ability of JCK cells was stronger than Choi-CK cells before gene silencing. In invasion assay (average of invasive cells in 5 areas, JCK vs. Choi-CK = 174.2 vs. 4.4, p = 0.000). DNA synthesis ability was also higher in JCK cells (average OD value, JCK vs. Choi-CK = 0.2827 vs. 0.1882, p = 0.000). Following transfection, the siRNA successfully suppressed PTK7 mRNA and protein expressions. Compared with the non-siRNA treated group, knocking down of PTK7 weaken the cells movement into the wound (1-remaining wound area at 48 hr/initial wound area at 0 hr, JCK vs. Choi-CK = 2.6 vs. 1.1, p = 0.014). Silencing of PTK7 in JCK cells also inhibited the invasive ability. The cell population migrated through the metrigel coated transwell was more than the non-siRNA group (average of invasive cells in 5 areas, JCK vs. siRNA-JCK =8.0 vs. 0.0, P = 0.021). Conclusions: The results suggested that high expression of PTK7 is associated with invasiveness of cholangiocarcinoma and PTK7 may be a potential therapeutic target for cholangiocarcinoma.
348 CLINICOPATHOLOGIC IMPLICATIONS OF SONIC HEDGEHOG PATHWAY ACTIVATION IN BILIARY ATRESIA H.Y. Jung, J. Jin, S.H. Kim, K. Lee, J.-J. Jang. Department of Pathology, Seoul National University College of Medicine, Seoul, Republic of Korea E-mail: [email protected] Background: Biliary atresia (BA) is the inflammatory disease of extrahepatic bile ducts accompanied with variable degree of hepatic fibrosis. Recently sonic Hedgehog (sHh) pathway has been suggested as the main pathway involving the repair of wounds, but the prognostic significance in BA still remains unclear. Thus, we sought to describe the way of sHh signaling acting on the remnant extrahepatic bile duct (EHBD) and the prognostic significance of activated sHh signaling in BA. Materials and Methods: We retrospectively selected 57 BA patients. Their EHBD specimens from Kasai operation and livers sampled by intraoperative biopsy or transplantation were stained for PTCH, sHh and Gli-2 via immunohistochemistry method. The immunohistochemical results were compared with clinicopathologic parameters of patients and clinical outcome. Results: The time of Kasai operation ranged from 14 to 413 days of life (mean; 69.88 days). 71.9% of the patients showed restoration of bile flow after Kasai operation, 57.8% of the patients had liver transplantation. Patients with failure of Kasai operation (group A) demonstrated delayed symptom onset, diagnosis and Kasai operation compared to the patients with successful Kasai operation (group B) (mean 35 vs 14.7 days, 80 vs 54.2 days, and 86 vs 6.59 days, respectively, p < 0.05). sHh and Gli-2 expressed in remaining bile duct and peribiliary glands, infiltrative lymphocytes and supporting fibroblasts. SHh and Gli-2 showed lower expression rate in group A than group B (A vs. B; 61.3% vs. 97.5%, p = 0.001). Patients with strong Gli-2 expression on peribiliary glands showed early disease recurrence (high vs. low; 43 vs. 124 months, p = 0.054), as well as Gli-2 expression on fibroblasts (high vs. low; 37 vs. 110 months, p = 0.031). Strong Gli-2 expression on portal area was correlated with the better overall survival rate of the native liver (high vs. low; 50 vs. 17 months, p = 0.006). Conclusion: Strong sHh signaling activation on EHBD results in the early disease recurrence after successful Kasai operation, but on the contrary, strong Gli-2 expression on portal area results in the better overall survival of the native liver. Activated sHh signaling would be the predictive marker of patients’ prognosis after Kasai operation. 349 BILE ACIDS DOWNREGULATE THE HUMAN HEPATIC ORGANIC ANION TRANSPORTER 7 1,2 C. Jungst ¨ , K. Klein2 , J.J. Eloranta2 , G.A. Kullak-Ublick2 . 1 Department of Medicine II, Saarland University Hospital, Homburg/Saar, Germany; 2 Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, Zurich, Switzerland E-mail: [email protected] Organic anion transporters (OATs) play a major role for the uptake, distribution and elimination of a wide range of exogenous and endogenous compounds. The human organic anion transporter 7 (hOAT7, SLC22A9) has been characterized as the first liverspecific member of the OAT family and mediates exchange of sulfate-conjugates for small chain fatty acids across the sinusoidal membrane. Bile acids decrease gene transcription via repression of the transcriptional activator hepatocyte nuclear factor-1a (HNF1a) involving a pathway dependent on the transcriptional repressor small heterodimer partner (SHP). Recently we have shown that OAT7 gene transcription is activated by HNF1a. Since transport activity is likely to be affected by expression levels, it is our aim to study the expression and regulation of the hOAT7 gene in conditions of elevated intracellular bile acid levels.
Journal of Hepatology 2012 vol. 56 | S71–S224
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348 CLINICOPATHOLOGIC IMPLICATIONS OF SONIC HEDGEHOG PATHWAY ACTIVATION IN BILIARY ATRESIA H.Y. Jung, J. Jin, S.H. Kim, K. Lee, J.-J. Jang. Department of Pathology, Seoul National University College of Medicine, Seoul, Republic of Korea E-mail: [email protected] Background: Biliary atresia (BA) is the inflammatory disease of extrahepatic bile ducts accompanied with variable degree of hepatic fibrosis. Recently sonic Hedgehog (sHh) pathway has been suggested as the main pathway involving the repair of wounds, but the prognostic significance in BA still remains unclear. Thus, we sought to describe the way of sHh signaling acting on the remnant extrahepatic bile duct (EHBD) and the prognostic significance of activated sHh signaling in BA. Materials and Methods: We retrospectively selected 57 BA patients. Their EHBD specimens from Kasai operation and livers sampled by intraoperative biopsy or transplantation were stained for PTCH, sHh and Gli-2 via immunohistochemistry method. The immunohistochemical results were compared with clinicopathologic parameters of patients and clinical outcome. Results: The time of Kasai operation ranged from 14 to 413 days of life (mean; 69.88 days). 71.9% of the patients showed restoration of bile flow after Kasai operation, 57.8% of the patients had liver transplantation. Patients with failure of Kasai operation (group A) demonstrated delayed symptom onset, diagnosis and Kasai operation compared to the patients with successful Kasai operation (group B) (mean 35 vs 14.7 days, 80 vs 54.2 days, and 86 vs 6.59 days, respectively, p < 0.05). sHh and Gli-2 expressed in remaining bile duct and peribiliary glands, infiltrative lymphocytes and supporting fibroblasts. SHh and Gli-2 showed lower expression rate in group A than group B (A vs. B; 61.3% vs. 97.5%, p = 0.001). Patients with strong Gli-2 expression on peribiliary glands showed early disease recurrence (high vs. low; 43 vs. 124 months, p = 0.054), as well as Gli-2 expression on fibroblasts (high vs. low; 37 vs. 110 months, p = 0.031). Strong Gli-2 expression on portal area was correlated with the better overall survival rate of the native liver (high vs. low; 50 vs. 17 months, p = 0.006). Conclusion: Strong sHh signaling activation on EHBD results in the early disease recurrence after successful Kasai operation, but on the contrary, strong Gli-2 expression on portal area results in the better overall survival of the native liver. Activated sHh signaling would be the predictive marker of patients’ prognosis after Kasai operation. 349 BILE ACIDS DOWNREGULATE THE HUMAN HEPATIC ORGANIC ANION TRANSPORTER 7 1,2 C. Jungst ¨ , K. Klein2 , J.J. Eloranta2 , G.A. Kullak-Ublick2 . 1 Department of Medicine II, Saarland University Hospital, Homburg/Saar, Germany; 2 Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, Zurich, Switzerland E-mail: [email protected] Organic anion transporters (OATs) play a major role for the uptake, distribution and elimination of a wide range of exogenous and endogenous compounds. The human organic anion transporter 7 (hOAT7, SLC22A9) has been characterized as the first liverspecific member of the OAT family and mediates exchange of sulfate-conjugates for small chain fatty acids across the sinusoidal membrane. Bile acids decrease gene transcription via repression of the transcriptional activator hepatocyte nuclear factor-1a (HNF1a) involving a pathway dependent on the transcriptional repressor small heterodimer partner (SHP). Recently we have shown that OAT7 gene transcription is activated by HNF1a. Since transport activity is likely to be affected by expression levels, it is our aim to study the expression and regulation of the hOAT7 gene in conditions of elevated intracellular bile acid levels.
Journal of Hepatology 2012 vol. 56 | S71–S224
S141