Identification of obstructive jaundice-related microRNAs in mouse liver.

BACKGROUND/AIMS: Although microRNAs are known to be post-transcriptional regulators in physiological and pathological events in the liver, their role in the obstructive jaundice liver remains unclear. METHODOLOGY: We sequenced the small RNA libraries of the bile duct ligation (BDL) mouse liver to detect the in vivo microRNA expression profiles of obstructive jaundice. We also validated the differential expression of microRNAs in the BDL liver using real-time PCR. Laser microdissection was performed to identify the origin of BDL-related microRNAs. An IL6-treated normal intrahepatic biliary epithelial cell line was used as an in vitro model of obstructive jaundice. RESULTS: We found microRNAs that were upregulated in the BDL liver (let-7a, let-7d, let-7f, let-7g, miR-21, miR-125a-5p, miR-125b-5p, miR-194, miR-199a-3p, miR-199a-5p, miR-214, miR-221, and miR-486). Furthermore, laser-microdissection analysis showed that miR-199a-5p was significantly upregulated in the intrahepatic bile duct of the BDL liver. The in vitro expression of miR-199a-5p was appreciably elevated in accordance with increased proliferation of IL6-treated cells. CONCLUSIONS: We revealed dynamic changes in microRNA expression during obstructive jaundice using the BDL model. MiR-199a-5p was likely associated with the proliferation of intrahepatic bile ducts. Our data will facilitate further study of the pathophysiological role(s) of microRNAs in the obstructive jaundice liver.

MicroRNA profiling of human intrahepatic cholangiocarcinoma cell lines reveals biliary epithelial cell-specific microRNAs.

Intrahepatic cholangiocarcinoma (ICC), which arises in the small bile ducts of the liver, is the second most common liver malignancy. Although modulation of microRNA (miRNA) expression has been shown to be a potent sign of malignant tumors, miRNA profiles of ICC remains unclear. We performed sequencing analysis of the small RNA libraries of 2 ICC cell lines (HuCCT1 and MEC) and one normal intrahepatic biliary epithelial cell line (HIBEpiC) to produce the miRNA profiles of ICC in vitro. Furthermore, by means of the real-time polymerase chain reaction (PCR) we validated the differential expression of miRNAs cloned exclusively or predominantly from each of the cell lines. A total of 35,759 small RNA clones were obtained from the 3 cell lines. We identified 27 miRNAs that were expressed exclusively or predominantly in each cell line. Subsequent validation with the real-time PCR confirmed that the miRNAs hsa-miR-22, -125a, -127, -199a, -199a*, -214, -376a, and -424 were expressed specifically in HIBEpiC but were downregulated in the ICC cell lines. Our study provides important information for facilitating studies of the functional role(s) of miRNAs in carcinogenesis of the hepatobiliary system. The biliary epithelial cell-specific miRNAs identified in this study may serve as potential biomarkers for ICC.

MicroRNA (miRNA) cloning analysis reveals sex differences in miRNA expression profiles between adult mouse testis and ovary.

MicroRNAs (miRNAs) are endogenous non-coding small RNAs that can regulate the expression of complementary mRNA targets. Identifying tissue-specific miRNAs is the first step toward understanding the biological functions of miRNAs, which include the regulation of tissue differentiation and the maintenance of tissue identity. In this study, we performed small RNA library sequencing in adult mouse testis and ovary to reveal their characteristic organ- and gender-specific profiles and to elucidate the characteristics of the miRNAs expressed in the reproductive system. We obtained 10,852 and 11 744 small RNA clones from mouse testis and ovary respectively (greater than 10,000 clones per organ), which included 6630 (159 genes) and 10,192 (154 genes) known miRNAs. A high level of efficiency of miRNA library sequencing was achieved: 61% (6630 miRNA clones/10,852 small RNA clones) and 87% (10,192/11,744) for adult mouse testis and ovary respectively. We obtained characteristic miRNA signatures in testis and ovary; 55 miRNAs were detected highly, exclusively, or predominantly in adult mouse testis and ovary, and discovered two novel miRNAs. Male-biased expression of miRNAs occurred on the X-chromosome. Our data provide important information on sex differences in miRNA expression that should facilitate studies of the reproductive organ-specific roles of miRNAs.

RT-PCR-based analysis of microRNA (miR-1 and -124) expression in mouse CNS.

More than 700 microRNAs (miRNAs) have been cloned, and the functions of these molecules in developmental timing, cell proliferation, and cancer have been investigated widely. MiRNAs are analyzed with Northern blot and sequential colony evaluation; however, reverse transcription-polymerase chain reaction (RT-PCR)-based miRNA assay remains to be developed. In this report, we describe improved real-time RT-PCR methods using specific or non-specific RT primer for the semi-quantitative analysis of miRNA expression. The use of the new methods in a model study revealed differential expression of miRNA-1 (miR-1) and miR-124 in mouse organs. Specifically, our methods revealed that miR-124 concentrations in the mouse central nervous system (CNS; cerebral cortex, cerebellum, and spinal cord) were more than 100 times those in other organs. By contrast, miR-1 expression in the CNS was 100-1000 times lower than that in skeletal muscle and heart. Furthermore, we revealed anatomically regional differences in miR-124 expression within the CNS: expression ratios versus the cerebral cortex were 60.7% for the cerebellum and 35.4% for the spinal cord. These results suggest that our RT-PCR-based methods would be a powerful tool for studies of miRNA expression that is associated with various neural events.

Occult gallbladder carcinoma after laparoscopic cholecystectomy: a report of four cases.

Eighty-four patients underwent laparoscopic cholecystectomy (LC) from January through August 2006. Of these patients, 4 (4.7%) were found to have occult gallbladder carcinoma (GC) either during or after the procedure. Two of the patients were women and 2 were men. The mean age was 75.0 years. One patient had mucosal tumors, 2 had subserosal tumors, and 1 had a serosal lesion. One of the 2 patients with subserosal tumors underwent radical surgery. In a previous study, 0.83% (10 of 1,195) of patients who had undergone LC were found to have occult GC, either during of after the procedure. The prevalence of gallbladder carcinoma has recently been increasing. GC has been reported in 0.3% to 1.5% of patients who have undergone cholecystectomy. Since the introduction of laparoscopic surgery, the number of cholecystectomies being performed has increased, which may explain why occult GC seems to be occurring more frequently. The prognosis for GC is poor, and surgical resection is the only potentially curative treatment. However, GC is difficult to diagnose at an early stage and difficult to recognize even in the advanced stages. Fifteen percent to 30% of patients show no preoperative or intraoperative evidence of malignancy. Occult GC is also increasing. Because flat infiltrating GC and GC with cholecystitis and numerous stones are difficult to diagnose preoperatively, we recommend taking frozen sections from patients who are of advanced age (older than 70 years), have a long history of stones, or have a thickened gallbladder wall.

Mucin-producing bile duct carcinoma arising from primary sclerosing cholangitis: a case report.

A 60-year-old woman with primary sclerosing cholangitis (PSC) and high levels of ALP, gamma-GTP, and DUPAN-2 was admitted to our institution for examination. The patient did not have ulcerative colitis or pancreatic intraductal papillary mucinous neoplasm. Imaging studies revealed atypical dilation of bile ducts in the left lobe of the liver. Repeated cytologic examinations of the bile showed atypical cells consistent with adenocarcinoma. The patient underwent extended resection of the left lobe of the liver and was found to have intraductal papillary carcinoma with associated mucin-producing bile duct carcinoma. This carcinoma fills dilated bile duct lumens with mucin. This tumor differs morphologically from typical cholangiocarcinoma, which is usually seen in the late stages of PSC. Just one case of mucin-producing bile duct carcinoma arising from PSC has been reported worldwide. The patient has had no signs of recurrence after 27 months. Patients with mucin-producing bile duct carcinoma, as in the case of its pancreatic counterpart, may have a better prognosis and a higher survival rate than patients with typical cholangiocarcinomas.

Effect of transforming growth factor-beta1 on human intrahepatic cholangiocarcinoma cell growth.

AIM: To elucidate the biological effects of transforming growth factor-beta1 (TGF-beta1) on intrahepatic cholan-giocarcinoma (ICC). METHODS: We investigated the effects of TGF-beta1 on human ICC cell lines (HuCCT1, MEC, and HuH-28) by monitoring the influence of TGF-beta1 on tumor growth and interleukin-6 (IL-6) expression in ICC cells. RESULTS: All three human ICC cell lines produced TGF-beta1 and demonstrated accelerated growth in the presence of TGF-beta1 with no apoptotic effect. Studies on HuCCT1 revealed a TGF-beta1-induced stimulation of the expression of TGF-beta1, as well as a decrease in TGF-beta1 mRNA expression induced by neutralizing anti-TGF-beta1 antibody. These results indicate that TGF-beta1 stimulates the production and function of TGF-beta1 in an autocrine fashion. Further, IL-6 secretion was observed in all three cell lines and exhibited an inhibitory response to neutralizing anti-TGF-beta1 antibody. Experiments using HuCCT1 revealed a TGF-beta1-induced acceleration of IL-6 protein expression and mRNA levels. These findings demonstrate a functional interaction between TGF-beta1 and IL-6. All three cell lines proliferated in the presence of IL-6. In contrast, TGF-beta1 induced no growth effect in HuCCT1 in the presence of small interfering RNA against a specific cell surface receptor of IL-6 and signal transducer and activator of transcription-3. CONCLUSION: ICC cells produce TGF-beta1 and confer a TGF-beta1-induced growth effect in an autocrine fashion. TGF-beta1 activates IL-6 production, and the functional interaction between TGF-beta1 and IL-6 contributes to ICC cell growth by TGF-beta1.

Cholecystitis caused by infiltration of immature myeloid cells: a case report.

A 59-year-old man with myelodysplastic syndrome who was hospitalized for evaluation of fever and generalized fatigue had elevated levels of C-reactive protein and pancytopenia. A search for a site of infection and empiric treatment with antibiotics were unsuccessful. Over 5 to 6 weeks right upper quadrant pain and rebound tenderness developed. Sonographic Murphys sign was present. Computed tomography showed thickening of the gallbladder wall, and repeated ultrasonography demonstrated changes consistent with cholecystitis. Open cholecystectomy was performed as an emergency procedure. Macroscopically the resected gallbladder showed an edematous and thickened wall. Histopathologic examination revealed transmural infiltration by atypical mononuclear cells with distinct nuclei. The cells showed immunohistochemical staining for CD15, indicating myeloid lineage. By 10 days after surgery, counts of leukocytes and leukoblasts had markedly increased, reaching 36,700/microL and 76.0%, respectively. The blast crisis was thought to indicate progression from myelodysplastic syndrome to leukemia. The patient died of progressive disease 12 days after surgery. We have described a rare case of acute cholecystitis caused by infiltration of immature myeloid cells to the gallbladder. An acute abdomen complicating hematologic disorders is life-threatening and requires prompt and appropriate treatment.

Combined neuroendocrine cell carcinoma and adenocarcinoma of the gallbladder: report of a case.

A 58-year-old man with a chief complaint of epigastralgia was admitted to our hospital. Physical examination disclosed a large, firm mass in the right hypochondrium. Abdominal computed tomography confirmed thickening of the gallbladder wall and a 15 x 8 cm mass occupying almost all of the right lobe and medial segment of the liver. With a preoperative diagnosis of malignant gallbladder tumor infiltrating the liver, right hepatic trisegmentectomy was performed. Histopathologic examination showed atypical cells with small round to oval nuclei and sparse eosinophilic cytoplasm, proliferating in a solid and focal nesting pattern. Near this small cell proliferation was a focus of tubular adenocarcinoma that showed a zone of transition from the small cell neuroendocrine pattern. The small cells demonstrated immunohistochemical reactivity for chromogranin A. Electron microscopy disclosed neurosecretory granules 150 nm in diameter, representing dense round core vesicles, confirming a neuroendocrine cell lineage. The patient was diagnosed with neuroendocrine cell carcinoma combined with adenocarcinoma of the gallbladder. Tumor recurrence became evident 3 months after surgery, and he died 4 months after surgery.

Incidental gallbladder cancer diagnosed during and after laparoscopic cholecystectomy.

With the increasingly widespread acceptance of laparoscopic cholecystectomy (LC), the number of cases of incidental gallbladder carcinoma (GBC) has increased; however, management of incidental GBC is a difficult issue in the absence of established guidelines. The present study aims to evaluate the treatment of patients with incidental GBC diagnosed with LC. We performed a 14-year review of 10 patients with GBC discovered with LC. From April 1991 through March 2004, we performed LC for 1,195 patients at Nippon Medical School Main Hospital. Of these patients, 10 (0.83%) were found to have GBC. Seven patients were women and 3 were men, with a mean age of 61.4 years. Four patients had mucosal tumors (pT1a), 5 had subserosal tumors (pT2), and 1 had a serosal lesion (pT3). Eight of the 10 patients underwent radical surgery. Two patients with pT1a tumors underwent no additional surgery. All 4 patients with pT1a tumors are alive without recurrence. One patient with a pT2 tumor with metastases to the liver and pericholedochal lymph nodes found with additional resection died of recurrence of metastasis to the liver and lung 70 months after LC. One patient with a pT2 tumor died of primary lung cancer 35 months after LC. The remaining 3 patients with pT2 tumors are alive without recurrence 51 to 128 months after surgery. One patient with a pT3 tumor is alive with no recurrence for 9 months. For stage Tis or T1a tumors, LC is sufficient. Patients with T1b tumors should undergo liver-bed resection and lymphadenectomy, and patients with >pT2 tumors should undergo systematic liver resection with lymphadenectomy. Even when incidental GBC diagnosed with LC is advanced, adequate additional surgery may improve the prognosis.

[Acute suppurative thyroiditis in 7 year-old girl with piriform sinus fistula].

A 7 year-old girl was admitted to our hospital with high grade fever and redness, swelling and tenderness in left neck. CT scan revealed cyst formation (4.5x3 cm) in left lobe of thyroid with swelling of surrounding lymphonodes. We diagnosed her as acute suppurative thyroiditis and treated her with intravenous antibiotics infusion and incisional drainage. After the treatment, the clinical course was uneventful. Pharyngograph revealed left piriform sinus fistula.

Simple closure of a perforated duodenal diverticulum: "a case report".

Spontaneous perforation of a duodenal diverticulum is a rare but serious complication with significant mortality rates. Just over 100 cases have been reported in the world literature. One case of perforated duodenal diverticulum treated by simple closure is reported. An elderly female was admitted to our hospital with an acute abdomen. Computed tomography of the abdomen showed retroperitoneal air around the duodenum and right kidney. Laparotomy with a Kocher maneuver disclosed a perforated diverticulum in the second portion of the duodenum. Although diverticulectomy is the most common treatment, simple closure of the perforated duodenal diverticulum with drainage was performed to avoid injury to the distal common bile duct and ampulla of Vater, which were close to the diverticulum. The patient has fully recovered and has been asymptomatic with no signs of recurrence for 25 months.

Spontaneous rupture of aneurysms of the ovarian artery at times remote from pregnancy.

Spontaneous rupture of an aneurysm of the ovarian artery is usually considered a rare complication of pregnancy and the puerperium. However, we observed this emergent condition in a 51-year-old postmenopausal woman. We report here our experiences and consider lessons about diagnosis and management that can be drawn from this case and 5 other published cases in multiparous middle-aged women. These lessons include application of contrast-enhanced computed tomography to focus emergent care, surgical intervention, and association with systemic inflammatory response syndrome. We also consider how the cases might shed new light on the pathogenesis and evolution of this condition.

MiR-376c down-regulation accelerates EGF-dependent migration by targeting GRB2 in the HuCCT1 human intrahepatic cholangiocarcinoma cell line.

MicroRNA miR-376c was expressed in normal intrahepatic biliary epithelial cells (HIBEpiC), but was significantly suppressed in the HuCCT1 intrahepatic cholangiocarcinoma (ICC) cell line. The biological significance of the down-regulation of miR-376c in HuCCT1 cells is unknown. We hypothesized that miR-376c could function as a tumor suppressor in these cells. To test this hypothesis, we sought the targets of miR-376c, and characterized the effect of its down-regulation on HuCCT1 cells. We performed proteomic analysis of miR-376c-overexpressing HuCCT1 cells to identify candidate targets of miR-376c, and validated these targets by 3'-UTR reporter assay. Transwell migration assays were performed to study the migratory response of HuCCT1 cells to miR-376c overexpression. Furthermore, microarrays were used to identify the signaling that were potentially involved in the miR-376c-modulated migration of HuCCT1. Finally, we assessed epigenetic changes within the potential promoter region of the miR-376c gene in these cells. Proteomic analysis and subsequent validation assays showed that growth factor receptor-bound protein 2 (GRB2) was a direct target of miR-376c. The transwell migration assay revealed that miR-376c significantly reduced epidermal growth factor (EGF)-dependent cell migration in HuCCT1 cells. DNA microarray and subsequent pathway analysis showed that interleukin 1 beta and matrix metallopeptidase 9 were possible participants in EGF-dependent migration of HuCCT1 cells. Bisulfite sequencing showed higher methylation levels of CpG sites upstream of the miR-376c gene in HuCCT1 relative to HIBEpiC cells. Combined treatment with the DNA-demethylating agent 5-aza-2'-deoxycytidine and the histone deacetylase inhibitor trichostatin A significantly upregulated the expression of miR-376c in HuCCT1 cells. We revealed that epigenetic repression of miR-376c accelerated EGF-dependent cell migration through its target GRB2 in HuCCT1 cells. These findings suggest that miR-376c functions as a tumor suppressor. Since metastasis is the major cause of death in ICC, microRNA manipulation could lead to the development of novel anti-cancer therapy strategies for ICC.

Sequencing and bioinformatics-based analyses of the microRNA transcriptome in hepatitis B-related hepatocellular carcinoma.

MicroRNAs (miRNAs) participate in crucial biological processes, and it is now evident that miRNA alterations are involved in the progression of human cancers. Recent studies on miRNA profiling performed with cloning suggest that sequencing is useful for the detection of novel miRNAs, modifications, and precise compositions and that miRNA expression levels calculated by clone count are reproducible. Here we focus on sequencing of miRNA to obtain a comprehensive profile and characterization of these transcriptomes as they relate to human liver. Sequencing using 454 sequencing and conventional cloning from 22 pair of HCC and adjacent normal liver (ANL) and 3 HCC cell lines identified reliable reads of more than 314000 miRNAs from HCC and more than 268000 from ANL for registered human miRNAs. Computational bioinformatics identified 7 novel miRNAs with high conservation, 15 novel opposite miRNAs, and 3 novel antisense miRNAs. Moreover sequencing can detect miRNA modifications including adenosine-to-inosine editing in miR-376 families. Expression profiling using clone count analysis was used to identify miRNAs that are expressed aberrantly in liver cancer including miR-122, miR-21, and miR-34a. Furthermore, sequencing-based miRNA clustering, but not individual miRNA, detects high risk patients who have high potentials for early tumor recurrence after liver surgery (P = 0.006), and which is the only significant variable among pathological and clinical and variables (P = 0,022). We believe that the combination of sequencing and bioinformatics will accelerate the discovery of novel miRNAs and biomarkers involved in human liver cancer.

Real-time PCR-based analysis of the human bile microRNAome identifies miR-9 as a potential diagnostic biomarker for biliary tract cancer.

Biliary tract cancer (BTC) is often difficult to diagnose definitively, even through histological examination. MicroRNAs (miRNAs) regulate a variety of physiological processes. In recent years, it has been suggested that profiles for circulating miRNAs, as well as those for tissue miRNAs, have the potential to be used as diagnostic biomarkers for cancer. The aim of this study was to confirm the existence of miRNAs in human bile and to assess their potential as clinical biomarkers for BTC. We sampled bile from patients who underwent biliary drainage for biliary diseases such as BTC and choledocholithiasis. PCR-based miRNA detection and miRNA cloning were performed to identify bile miRNAs. Using high-throughput real-time PCR-based miRNA microarrays, the expression profiles of 667 miRNAs were compared in patients with malignant disease (n = 9) and age-matched patients with the benign disease choledocholithiasis (n = 9). We subsequently characterized bile miRNAs in terms of stability and localization. Through cloning and using PCR methods, we confirmed that miRNAs exist in bile. Differential analysis of bile miRNAs demonstrated that 10 of the 667 miRNAs were significantly more highly expressed in the malignant group than in the benign group at P<0.0005. Setting the specificity threshold to 100% showed that some miRNAs (miR-9, miR-302c*, miR-199a-3p and miR-222*) had a sensitivity level of 88.9%, and receiver-operating characteristic analysis demonstrated that miR-9 and miR-145* could be useful diagnostic markers for BTC. Moreover, we verified the long-term stability of miRNAs in bile, a characteristic that makes them suitable for diagnostic use in clinical settings. We also confirmed that bile miRNAs are localized to the malignant/benign biliary epithelia. These findings suggest that bile miRNAs could be informative biomarkers for hepatobiliary disease and that some miRNAs, particularly miR-9, may be helpful in the diagnosis and clinical management of BTC.

Improvement of intraoperative frozen section diagnosis in patients with biliary strictures by Levovist injection into the bile duct on color Doppler ultrasonography.

BACKGROUND: This study evaluates the efficiency of color Doppler ultrasonography-guided intraoperative pancreatic biopsy (CDUS-IPB) using Levovist injected into the bile duct in conjunction with stimulated acoustic emission (SAE) in patients with biliary strictures. METHODS: The study was performed on 12 patients. After completing a conventional intraoperative pancreatic biopsy (c-IPB), each subject underwent CDUS with SAE imaging using Levovist. Upon identification of the biliary stricture, the IPB was taken from the area surrounding the stricture on the same imaging setting. Section diagnosis of the CDUS-IPB specimen was compared to that of the c-IPB specimen and resected tissue. RESULTS: Biliary strictures were identified as enhanced areas of color Doppler signal on CDUS. CDUS-IPB provided adequate specimens from the biliary strictures in all cases and corrected false-negative diagnoses by c-IPB in three cases. Section diagnosis by CDUS-IPB corresponded to the permanent section diagnosis. There were no complications. CONCLUSIONS: CDUS-IPB with Levovist is an accurate diagnostic tool. The method is especially useful for patients with a suspected malignant biliary stricture who show no tumor mass in preoperative images and no evidence of malignancy on cytologic examinations.

Short hairpin RNA modulates transforming growth factor beta signaling in life-threatening liver failure in mice.

BACKGROUND & AIMS: Transforming growth factor beta (TGF-beta) receptor II (TGF-betaRII), which is essential for TGF-beta signaling and is involved in the causation or participates in the pathway of various human disorders, is consequently considered a key target for therapeutics and analysis of the pathophysiology associated with disruption of the TGF-beta system. In the liver, TGF-beta plays an essential role in hepatocyte apoptosis, growth inhibition, and progression of fibrogenesis. There is a critical need to introduce technology involving the TGF-beta system, such as RNA interference (RNAi), which has high potential for in vivo therapeutics and analytical activities. METHODS: Here, we investigated the effect of short hairpin RNA targeting TGF-betaRII, using hepatocyte injury in human and mouse cell lines and liver injury mouse models. RESULTS: We demonstrated that short hairpin RNA targeting TGF-betaRII can be used to silence TGF-betaRII genes in mouse and human cell lines, and physiologic and morphologic changes in hepatocytes suffering from acute injury are spared by RNAi-mediated gene silencing of the target gene and by suppressing downstream signal transduction. Furthermore, short hairpin RNA targeting TGF-betaRII protected mice from life-threatening acute liver failure. CONCLUSIONS: Our study suggests the potential use of TGF-betaRII silencing by RNAi as an analytical tool for TGF-beta signaling and gene-specific therapy in human disorders.