STAT3 promotes migration and invasion of cholangiocarcinoma arising from choledochal cyst by transcriptionally inhibiting miR200c through the c-myb/MEK/ERK signaling pathway.

Signal transducer and activator of transcription 3 (STAT3) have been highlighted in cancer regulation. Its roles in Cholangiocarcinoma (CCA) arising from the choledochal cyst (CC) were unclear. Here, we attempted to elucidate the roles of STAT3 in CCA-CC and explore its mechanism. A total of 20 patients with CCA arising from CC, that underwent CC excision in the infant stage were included. The expressions of STAT3, miR200c and c-Myb in clinical samples were assessed by RT-qPCR and/or western blot. Their expression correlations in tumor tissues were evaluated by Pearson correlation analysis. Their roles in CCA cell migration and invasion were investigated by gene silence using siRNA or miRNA inhibitor mediated approach and MEK activator. The expression levels of EMT, metastasis and MEK/ERK pathway-related proteins were checked by western blot. The high expressions of STAT3 and c-Myb, and low expression of miR200c were detected in CCA samples. We defined the transcription inhibition of STAT3 in miR200c expression and the negative correlation between miR200c and c-Myb expression. Silence of STAT3 increased miR200c expression and retarded the migration and invasion of CCA cells, accompanied by decreased levels of Vimentin, N-cadherin, MMP2 and MMP9, and elevated expression of E-cadherin, resulting in inactivating MEK/ERK pathway. MiR200c inhibitor reversed the changes induced by STAT3 silence, which was restored by si-c-Myb. MEK activator significantly reversed the inactivation of the MEK/ERK pathway induced by si-STAT3+miR200c inhibitor+si-c-Myb. In summary, the silence of STAT3 suppressed metastasis and progression of CCA cells by regulating miR200c through the c-Myb mediated MEK/ERK pathway, suggesting STAT3 is the effective target for CCA arising from CC.

Reduced peroxisome proliferator-activated receptor-α and bile acid nuclear receptor NR1H4/FXR may affect the hepatic immune microenvironment of biliary atresia.

Background: Biliary atresia (BA) is a childhood liver disease characterized by fibrous obstruction and obstruction of the extrahepatic biliary system and is one of the most common and serious biliary disorders in infants. Significant inflammation and fibrosis of the liver and biliary tract are the most prominent features, regardless of the initial damage to the BA. Abnormalities in innate or adaptive immunity have been found in human patients and mouse models of BA. We previously reported that children with BA had abnormal lipid metabolism, including free serum carnitine. Objective: To study gene and protein expression levels of the hepatic peroxisome proliferator-activated receptor-α (PPARα) signaling pathway and farnesoid X receptor (FXR) in BA and BA fibrosis, and assess their clinical values. Methods: Low expression of PPARα and NR1H4 (FXR) in BA were validated in the Gene Expression Omnibus database. Functional differences were determined by gene set enrichment analysis based on of PPARα and NR1H4 expression. BA patients from GSE46960 were divided into two clusters by using consensus clustering according to PPARα, NR1H4, and SMAD3 expression levels, and immunoinfiltration analysis was performed. Finally, 58 cases treated in our hospital were used for experimental verification. (IHC: 10 Biliary atresia, 10 choledochal cysts; PCR: 10 Biliary atresia, 14 choledochal cysts; WB: 10 Biliary atresia, 4 choledochal cysts). Results: Bioinformatics analysis showed that the expression of PPARα, CYP7A1 and NR1H4 (FXR) in the biliary atresia group was significantly lower than in the control group. More BA-specific pathways, including TGFß signaling pathway, P53 signaling pathway, PI3K-AKT-mTOR signaling pathway, etc., are enriched in BA patients with low PPARα and NR1H4 expression. In addition, low NR1H4 expression is abundant in inflammatory responses, IL6/STAT3 signaling pathways, early estrogen responses, IL2 STAT5 signaling pathways, and TGFß signaling pathways. The TGFß signaling pathway was significant in both groups. According to the expression of PPARα, NR1H4 and SMAD3, a key node in TGFß pathway, BA patients were divided into two clusters using consensus clustering. In cluster 2, SMAD3 expression was high, and PPARα and NR1H4 expression were low. In contrast to cluster 1, immune cell infiltration was higher in cluster 2, which was confirmed by immunohistochemistry. The mRNA and protein levels of PPARα and NR1H4 in BA patients were lower than in the control group by immunohistochemistry, Western blot analysis and real-time PCR. Conclusions: The downregulation of PPARα and NR1H4 (FXR) signaling pathway may be closely related to biliary atresia.

Diminution of the Primary Cilia From the Intrahepatic Cholangiocytes in a Pediatric Choledochal Cyst.

Choledochal cyst (CC) is a cystic disease predominantly involving the extrahepatic biliary tree. Biliary atresia (BA), another disorder of the extrahepatic biliary tree, is sometimes considered to be in the same spectrum as pediatric CC. Recently, the absence and/or the structural abnormality of the primary cilia in the intrahepatic cholangiocytes have been implicated in the pathogenesis of BA. We aimed to evaluate the expression of primary ciliary proteins in the intrahepatic cholangiocytes in cases of pediatric CC and compare it with normal control and BA. We performed immunohistochemistry for primary ciliary proteins (acetylated-α-tubulin and double-cortin domain containing 2) on the liver biopsies of control liver (n=5), pediatric CC (n=13), and BA (n=14). We also compared the expression with various clinical, biochemical, histopathologic (portal fibroinflammation and ductal plate malformation), and immunohistochemical (proliferative index) data. There was significant loss of primary cilia from the intrahepatic cholangiocytes in cases of CC and BA as compared with the normal control by both immunostains (CC: P=0.003 and 0.001, respectively; BA: P=0.001 and 0.001, respectively). There was no significant difference between the CC and BA in terms of ciliary protein loss. The loss of the ciliary proteins occurred irrespective of the proliferative (MIB-1 labeling) index, portal fibroinflammation, or ductal plate malformation. The loss of cilia did not correlate with the clinical follow-up in cases of pediatric CC. The loss of primary cilia from the intrahepatic cholangiocytes may be crucial in the etiopathogenesis of pediatric CC.

Increased survivin expression and its association with clinical parameters of congenital choledochal cysts.

The aim of the current study was to investigate survivin expression in congenital choledochal cysts (CCCs), and its associations with clinical parameters of CCCs. In total, 121 children with CCCs were included in this study as the case group, and their cysts were staged according to the Todani classification system. Additionally, 49 normal gallbladder specimens from healthy children were included as the control group. Survivin detection was conducted using immunohistochemical staining. Associations between positive survivin expression and clinical parameters of CCCs were then analyzed. Positive survivin expression was observed in the cytoplasm, and was seen as granular with yellow or dark brown staining. In the case group, positive survivin expression was detected in most tissues. Specifically, compared to that of normal tissues, the cystic-shaped and fusiform-shaped CCC tissues had significantly higher positive survivin expression rates (all P < 0.05). Importantly, positive survivin expression was also shown to be significantly associated with gender and histological type (both P < 0.05). In conclusion, increased survivin expression was observed in CCC tissues, and was correlated with certain clinical parameters of CCCs, suggesting a possible prognostic value of survivin for CCC progression.

Congenital choledochal malformation: search for a marker of epithelial instability.

PURPOSE: There is a predisposition to the development of malignancy in congenital choledochal malformation (CCM) although the degree of risk is unknown. We investigated the role of CA19-9 in bile and the MIB-1 (Ki-67) epithelial proliferation index as markers of an at risk choledochal epithelium at the time of definitive surgery. METHODS: Bile collected at surgery was analyzed for levels of amylase (as a surrogate of pancreatic reflux) and CA19-9. Immunohistochemical staining for CA19-9 and MIB-1 index (expressed as %) was performed on resected specimens. Data are quoted as median (IQR) and differences assessed using non-parametric statistics. A P value of 0.05 was regarded as significant. RESULTS: Our study group consisted of 78 children with CCM (Type 1 fusiform, n=34; Type 1 cystic, n=30 and Type 4, n=14). Median bile CA19-9 was 159,400 (6-1×10(6)) kU/L. There was no correlation with bile amylase (P=0.49) or biliary pressure (P=0.17) but modest correlation with bilirubin (rs=0.24; P=0.02). In contrast, bile amylase was correlated with plasma γ-glutamyl transpeptidase (P=0.02), alkaline phosphatase (P=0.05) and aspartate aminotransferase (P=0.02); and inversely correlated with biliary pressure (rs=-0.38; P<0.0008). Epithelial expression of CA19-9 and MIB-1 was assessed in 43 specimens. CA19-9 was diffusely expressed on all choledochal epithelium. MIB-1 expression was divided into: high expression (>40%) n=3; moderate (20-40%) n=5, low (6-20%) n=7 and very low (≤5%) n=28. There was no correlation with choledochal pressure (P=0.87), CA19-9 (P=0.51) or bile amylase (P=0.55). CONCLUSION: Biliary CA19-9 levels were grossly (and unexpectedly) raised in choledochal malformation and appear to arise from biliary rather than pancreatic epithelium. MIB-1 confirms that a small proportion (19%) has marked epithelial proliferation but no clinical correlates could be identified.

Role of CD56-expressing immature biliary epithelial cells in biliary atresia.

AIM: To analyze the clinical and pathological parameters and expression of the neural cell adhesion molecule (CD56) in patients with biliary atresia (BA). METHODS: Established clinical laboratory markers of hepatic function, including enzyme activity, protein synthesis, and bilirubin metabolism, were evaluated in patients with BA and compared with those in patients with choledochal cysts and neonatal hepatitis. Pathological changes in tissue morphology and fibrosis were examined by histological and tissue collagen staining. Immunohistochemical staining for the biliary epithelial cell markers CD56 and CK19 together with the Notch signaling related molecules Notch1 and Notch2 was performed in the context of alterations in the structure of intrahepatic biliary ducts. RESULTS: Differences in some clinical laboratory parameters among the three diseases examined were observed, but they did not correlate with the pathological classification of fibrosis in BA. Immunohistochemical staining showed the presence of CD56-positive immature bile ducts in most patients (74.5%) with BA but not in patients with choledochal cysts or neonatal hepatitis. The number of CD56-expressing cells correlated with disease severity, with more positive cells present in the later stages of liver damage (81.8% vs 18.2%). Furthermore, bile plugs were mainly found in CD56-positive immature biliary ducts. Notch signaling was a key regulatory pathway in biliary duct formation and played a role in tissue fibrosis. Notch1 was co-expressed in CD56-positive cells, whereas Notch2 was found exclusively in blood vessels in the portal area of patients with BA. CONCLUSION: The maturation of biliary epithelial cells and the expression of Notch may play a role in the pathogenesis of BA.

The Density of Interstitial Cells of Cajal Is Diminished in Choledochal Cysts.

BACKGROUND AND AIMS: Interstitial cells of Cajal (ICC) have been shown to be present in the extrahepatic biliary tract of animals and humans. However, ICC distribution in choledochal cysts (CC) has not been investigated. A study was conducted to investigate the distribution of ICC in the extrahepatic biliary tract, including CC, in pediatric human specimens. METHOD: The specimens were divided into two main groups as gallbladders and common bile ducts. Gallbladders were obtained from the cholelithiasis, CC operations and autopsies. Common bile ducts were obtained from autopsies. Tissues were stained using c-kit immunohistochemical staining. ICC were assessed semi-quantitatively by applying morphological criteria and were counted as the number of cells/0.24 mm(2) in each area under light microscopy. RESULTS: A total of 35 gallbladders and 14 CC were obtained from operations. Ten gallbladders plus common bile ducts were obtained from autopsies. The mean numbers of ICC in the gallbladders of cholelithiasis and the gallbladders of CC were 12.2 ± 4.9 and 5.3 ± 1.2, respectively (p = 0.003). The mean numbers of ICC in the common bile ducts and CC were 9.8 ± 2.9 and 3.4 ± 1.4, respectively (p = 0.001). CONCLUSION: The scarcity of ICC in the extrahepatic biliary tract may be responsible for the etiopathogenesis of the CC.

Role of follicle-stimulating hormone on biliary cyst growth in autosomal dominant polycystic kidney disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a common genetic disorder characterized by the progressive development of renal and hepatic cysts. Follicle-stimulating hormone (FSH) has been demonstrated to be a trophic factor for biliary cells in normal rats and experimental cholestasis induced by bile duct ligation (BDL). AIMS: To assess the effect of FSH on cholangiocyte proliferation during ADPKD using both in vivo and in vitro models. METHODS: Evaluation of FSH receptor (FSHR), FSH, phospho-extracellular-regulated kinase (pERK) and c-myc expression in liver fragments from normal patients and patients with ADPKD. In vitro, we studied proliferating cell nuclear antigen (PCNA) and cAMP levels in a human immortalized, non-malignant cholangiocyte cell line (H69) and in an immortalized cell line obtained from the epithelium lining the hepatic cysts from the patients with ADPKD (LCDE) with or without transient silencing of the FSH gene. RESULTS: Follicle-stimulating hormone is linked to the active proliferation of the cystic wall and to the localization of p-ERK and c-myc. This hormone sustains the biliary growth by activation of the cAMP/ERK signalling pathway. CONCLUSION: These results showed that FSH has an important function in cystic growth acting on the cAMP pathway, demonstrating that it provides a target for medical therapy of hepatic cysts during ADPKD.

Monoamine oxidase A expression is suppressed in human cholangiocarcinoma via coordinated epigenetic and IL-6-driven events.

The secretion of dopamine and serotonin is increased in cholangiocarcinoma, which has growth-promoting effects. Monoamine oxidase A (MAOA), the degradation enzyme of serotonin and dopamine, is suppressed in cholangiocarcinoma via an unknown mechanism. The aims of this study were to (i) correlate MAOA immunoreactivity with pathophysiological parameters of cholangiocarcinoma, (ii) determine the mechanism by which MAOA expression is suppressed and (iii) evaluate the consequences of restored MAOA expression in cholangiocarcinoma. MAOA expression was assessed in cholangiocarcinoma and nonmalignant controls. The control of MAOA expression by promoter hypermethylation was evaluated and the contribution of interleukin-6 (IL-6) signaling to the suppression of MAOA expression was determined. The effects of MAOA overexpression on cholangiocarcinoma growth and invasion were also assessed. MAOA expression is correlated with differentiation, invasion and survival in cholangiocarcinoma. The MAOA promoter was hypermethylated immediately upstream of the start codon in cholangiocarcinoma samples and cell lines but not in nonmalignant counterparts. IL-6 signaling also decreased MAOA expression via a mechanism independent of hypermethylation, involving the regulation of the balance between SP-1 transcriptional activity and its inhibitor, R1 repressor. Inhibition of both IL-6 signaling and DNA methylation restored MAOA levels to those observed in cholangiocytes. Forced MAOA overexpression inhibited cholangiocarcinoma growth and invasion. MAOA expression is suppressed by the coordinated control of promoter hypermethylation and IL-6 signaling. MAOA may be a useful prognostic marker in the management of cholangiocarcinoma, and therapies designed to increase MAOA expression might prove beneficial in the treatment of cholangiocarcinoma.

Ursodeoxycholic acid is conjugated with taurine to promote secretin-stimulated biliary hydrocholeresis in the normal rat.

BACKGROUND & AIMS: Secretin induces bicarbonate-rich hydrocholeresis in healthy individuals, but not in untreated patients with primary biliary cirrhosis (PBC). Ursodeoxycholic acid (UDCA)--the first choice treatment for PBC--restores the secretin response. Compared with humans, secretin has poor effect in experimental normal-rat models with biliary drainage, although it may elicit hydrocholeresis when the bile-acid pool is maintained. In view of the benefits of UDCA in PBC, we used normal-rat models to unravel the acute contribution of UDCA (and/or taurine-conjugated TUDCA) for eliciting the biliary secretin response. METHODS: Intravascular and/or intrabiliary administration of agonists and inhibitors was performed in normal rats with biliary monitoring. Secretin/bile-acid interplay was analyzed in 3D cultured rat cholangiocytes that formed expansive cystic structures with intralumenal hydroionic secretion. RESULTS: In vivo, secretin stimulates hydrocholeresis upon UDCA/TUDCA infusion, but does not modify the intrinsic hypercholeretic effect of dehydrocholic acid (DHCA). The former effect is dependent on microtubule polymerization, and involves PKCα, PI3K and MEK pathways, as shown by colchicine (i.p.) and retrograde biliary inhibitors. In vitro, while secretin alone accelerates the spontaneous expansion of 3D-cystic structures, this effect is enhanced in the presence of TUDCA, but not UDCA or DHCA. Experiments with inhibitors and Ca(2+)-chelator confirmed that the synergistic effect of secretin plus TUDCA involves microtubules, intracellular Ca(2+), PKCα, PI3K, PKA and MEK pathways. Gene silencing also demonstrated the involvement of the bicarbonate extruder Ae2. CONCLUSIONS: UDCA is conjugated in order to promote secretin-stimulated hydrocholeresis in rats through Ae2, microtubules, intracellular Ca(2+), PKCα, PI3K, PKA, and MEK.

Congenital biliary dilatation may consist of 2 disease entities.

BACKGROUND/PURPOSE: This study aims to establish the possible mechanisms of pathogenesis of congenital biliary dilatation and to classify the disease accordingly. METHODS: Radiologic features of congenital biliary dilatation and pancreaticobiliary malunion in 107 affected children were examined and correlated with laboratory results. Relative lengths/diameters were calculated to provide comparison between children of different ages. Intraluminal pressures of common bile duct (CBD) were measured intraoperatively. RESULTS: The minimal relative diameters of distal CBD negatively correlated with the maximal relative diameters/lengths of dilated CBD, the maximal relative diameters of common hepatic duct, and left/right hepatic ducts. The intraluminal pressure in patients with a stenotic distal CBD (stenotic group) was significantly higher than that in patients with a nonstenotic distal CBD (nonstenotic group). The narrower the distal CBD, the more deranged the liver function. Conversely, serum/bile amylase levels were more elevated in the nonstenotic group. Common channel protein plugs were only found in the nonstenotic group, whereas common hepatic duct strictures, intrahepatic duct dilatations, and calculi were detected more frequently in the stenotic group. CONCLUSION: We propose to categorize congenital biliary dilatation into 2 subgroups: (1) cystic type with stenotic distal CBD associated with deranged liver function and common hepatic duct stricture and (2) fusiform type with nonstenotic distal CBD associated with pancreatitis and common channel protein plugs. Different underlying pathologies of each group require different operative strategies.

[A case of early bile duct cancer arising from villous adenoma in choledochal cyst].

Choledochal cyst is an uncommon premalignant anomaly. The morphology and pathogenesis of the premalignant lesion of cholangiocarcinoma arising from the choledochal cyst has not been well described. Herein, we report a rare case of bile duct adenoma arising from choledochal cyst with anomalous union of pancreaticobiliary duct (AUPBD). 50-year-old woman was admitted to our hospital with the complaint of epigastric pain. She had received common bile duct (CBD) exploration and choledocholithotomy and cholecystectomy 3 months earlier under the diagnosis of multiple CBD stones. Intraoperalive cholangiogram was not remarkable except CBD dilatation at that time. Endoscopic retrograde cholangiopancreatography revealed choledochal cyst with AUPBD and round filling defect which disappeared easily on the balloon cholaniogram. On magnetic resonance cholangiopancreatography, the filling defect was confirmed as 2 cm polypoid mass attached to the distal bile duct wall. At laparotomy, a soft whitish mass was palpable on the lower CBD. On histological examination, adenoma with focal carcinoma change arising from choledochal cyst was diagnosed.

Acidic and basic solutions dissolve protein plugs made of lithostathine complicating choledochal cyst/pancreaticobiliary maljunction.

BACKGROUND: Symptoms of choledochal cysts are caused by protein plugs made of lithostathine, which block the long common channel and increase pancreaticobiliary ductal pressure. Agents that dissolve protein plugs can provide relief from or prevent symptoms. In the present study, drugs reportedly effective for pancreatic and biliary stones were used in dissolution tests. METHODS: Protein plugs were obtained from choledochal cysts during surgery in two children (5- and 6-year-old girls). Plugs approximately 2 mm in diameter were immersed in citric acid, tartaric acid, dimethadione, bromhexine, dehydrocholic acid, sodium citrate, hydrochloric acid, and sodium hydroxide solutions under observation with a digital microscope. The pH of each solution was measured using a pH meter. RESULTS: Plugs dissolved in citric acid (5.2 mM; pH 2.64), tartaric acid (6.7 mM; pH 2.51), dimethadione (75 mM; pH 3.70), hydrochloric acid (0.5 mM; pH 3.13), and sodium hydroxide (75 mM; pH 12.75) solutions. Plugs did not dissolve in dimethadione (7.5 mM; pH 4.31), bromhexine (0.1%; pH 4.68), dehydrocholic acid (5%; pH 7.45), and sodium citrate (75 mM; pH 7.23) solutions. CONCLUSION: Protein plugs in choledochal cysts are dissolved in acidic and basic solutions, which may eliminate longitudinal electrostatic interactions of the lithostathine protofibrils.

Upstream stimulatory factor 2 is implicated in the progression of biliary atresia by regulation of hepcidin expression.

BACKGROUND: Hepcidin is downregulated during the progression of biliary atresia (BA), but the mechanism is still unknown. METHODS: We analyzed single nucleotide polymorphism of rs7251432 and 916145 within hepcidin and its upstream, USF2 gene, respectively, in 52 patients of BA and 96 healthy controls. Liver tissues were obtained from 10 patients with early and late stage of BA, 10 patients with choledochal cyst, and 4 normal controls to study upstream stimulatory factor 2 (USF2) messenger RNA (mRNA) and protein expressions. Chromatin immunoprecipitation assay and USF2-specific short interference RNA (siRNA) were used in human HepG2 cells to show that USF2 can regulate hepcidin expression. RESULTS: C and CC allele frequencies of rs916145 of USF2 were significantly higher in patients with BA than in healthy controls. There was also significantly higher USF2 protein nuclear translocation in the early stage of BA than in the late stage, which was compatible with higher hepcidin mRNA expression in the early stage of BA. Chromatin immunoprecipitation assay demonstrated physiologic bindings of USF2 to the hepcidin promoter in HepG2 cells. USF2 siRNA also significantly knocked down hepcidin mRNA expression. CONCLUSION: The study demonstrates that C allele of rs916145 in USF2 gene has more frequency for developing BA, and decreased USF2 protein nuclear translocation might partly play a role in the decreased hepcidin expression in the cholestatic liver injury of the late stage of BA.

[Expression and significance of aPKC-iota and E-cadherin in cholangiocarcinoma].

BACKGROUND & OBJECTIVE: Studies showed that the abnormal expression of atypical protein kinase C iota subtype (aPKC-iota) and E-cadherin plays an important role in tumor genesis and progression. This study was to investigate the expression of aPKC-iota and E-cadherin in cholangiocarcinoma, and analyze molecular mechanisms of the invasion and metastasis of cholangiocarcinoma. METHODS: The expression of aPKC-iota and E-cadherin in 9 specimens of benign bile duct tissues and 35 specimens of cholangiocarcinoma was detected by EnVision immunohistochemistry, and their correlations to the clinicopathologic characteristics and invasion of cholangiocarcinoma were analyzed. RESULTS: The positive rate of aPKC-iota was significantly higher in cholangiocarcinoma than in benign bile duct tissues (68.6% vs. 11.1%, P = 0.006), while the positive rate of E-cadherin was significantly lower in cholangiocarcinoma than in benign bile duct tissues (37.1% vs. 88.9%, P = 0.016). aPKC-iota expression was negatively correlated to E-cadherin expression (r = -0.287, P < 0.05). aPKC-iota expression was positively and E-cadherin expression was negatively correlated to the differentiation and invasion of cholangiocarcinoma (P < 0.05). CONCLUSIONS: The expression of aPKC-iota and E-cadherin may reflect the differentiation and invasive potential of cholangiocarcinoma. As a polar regulation-associated protein, aPKC-iota may play a role in the invasion and metastasis of cholangiocarcinoma.

Expression of toll-like receptors and type 1 interferon specific protein MxA in biliary atresia.

Viral infection and type I interferon have been implicated in the pathogenesis of biliary atresia (BA), but the expression of toll-like receptors (TLRs) that recognize viruses, as well as of type 1 interferon specific signaling molecules are still unknown in BA. Fresh liver tissues were obtained from patients in early and late stage of BA and from patients with choledochal cyst (CC), as well as from normal controls receiving liver resection for benign lesion other than cholestasis or fibrosis. Archived liver tissues from patients with neonatal hepatitis (NH) were obtained for immunohistochemical studies. TLR2, 3, 4, 7 and 9 that recognized Gram-positive bacteria, double-stranded RNA virus, lipopolysaccharide, single-stranded RNA virus and DNA virus, respectively, were studied. Real-time quantitative reverse transcription polymerase chain reaction (QRT-PCR) was used to quantitate TLR, type I interferon specific molecule MxA, interleukin-6 (IL-6) and IL-8 mRNA expression and immunohistochemistry for TLR 7 and MxA protein staining. These results show that there were significantly higher TLR7 and lower TLR3 and TLR9 mRNA expression in early stage of BA than in CC. MxA mRNA expression was also significantly higher in early stage of BA and in CC than in late stage of BA. Immunoreactive TLR7 and MxA staining was higher in early stage of BA than in late stage of BA, NH and CC, which was associated with significantly higher IL-8 mRNA expression in BA than in CC. The results implicate involvement of TLRs, particularly TLR7, and type 1 specific interferon signaling in the pathogenesis of BA, especially in early stage, which is associated with upregulation of inflammatory cytokines IL-8.

Dynamic study of pancreaticobiliary reflux using secretin-stimulated magnetic resonance cholangiopancreatography in patients with choledochal cysts.

BACKGROUND/PURPOSE: Refluxes through pancreaticobiliary maljunctions play an important role in the pathophysiology of choledochal cysts. Dynamic studies of the pancreaticobiliary tract were performed using secretin-stimulated magnetic resonance cholangiopancreatography. METHODS: Six patients with choledochal dilation were recruited for this study. Four patients exhibited cystic and 2 exhibited fusiform dilatation of the common bile duct (CBD). Magnetic resonance cholangiopancreatography images were obtained every minute during the 15-minute period after secretin stimulation. The sequential morphological changes in the biliary trees, pancreas, and duodenum were assessed, and the total pixel values of these organs were measured for each image, then plotted as a ratio against the baseline image. RESULTS: In 2 cases involving cystic dilatation, the intensity of bile duct images continued to rise after secretin stimulation. In a case involving fusiform dilatation, a transitory elevation in CBD intensity was observed. In 3 cases involving fusiform or cystic dilatation, the intensity of CBD did not change notably. In all cases, the duodenum was filled well after secretin stimulation. CONCLUSIONS: The sustained elevation in bile duct intensity after secretin stimulation indicates reflux and bile stasis. Transitory elevation may indicate reflux without stasis. This method allows assessment of the dynamics of pancreatic and bile fluid under more physiologic condition.

CD56 expression aids in the differential diagnosis of cholangiocarcinomas and benign cholangiocellular lesions.

CD56 (neuronal cell adhesion molecule, N-CAM) has been reported in neuroendocrine tumours and as a marker of reactive biliary epithelial cells. However, up to date, it is not used to distinguish malignant from non-malignant biliary lesions. In this study, we systematically examined CD56 expression on 98 tumours arising from the biliary tree as well as intrahepatic conditions with reactive neoductules. When neuroendocrine carcinomas are excluded, only 4 of 32 (12.5%) cholangiocarcinomas expressed CD56, 2 of which showed clear cell morphology. Reactive bile ductules adjacent to cirrhotic nodules as well as in focal nodular hyperplasia were CD56 positive. Twelve of 17 (70.5%) bile duct adenomas were CD56 positive, whereas von Meyenburg complexes expressed CD56 only very focally in less than 5% of lesional cells. Bile duct cysts were negative for CD56 with the exception of focally interspersed neuroendocrine cells, similar to that seen in segmental bile ducts. Thus, if van Meyenburg complexes are excluded, CD56 can be used to differentiate intrahepatic non-neoplastic from neoplastic proliferations, which is a helpful diagnostic tool in small liver biopsies.