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324 Bone Marrow-Derived Liver-Committed Stem Cells Give Rise to Combined Hepatocholangio-Carcinomas in Rats
G-CSFR and the administration of exogenous G-CSF accelerated the development of CHCCs and increased the number of BM-derived tumors. Conclusions. In our model of CHCC, BM cells could differentiate into OCs and subsequently give rise to liver tumors. The CHCCs expressed G-CSFR and the administration of G-CSF accelerated the development of the disease and increased the number of BM-derived liver tumors.
Photodynamic Therapy Versus Incomplete Resection in Hilar Cholangiocarcinoma Thomas Zoepf, Gernot M. Kaiser, Alexander Dechene, Philip A. Hilgard, Guido Gerken, Hauke Lang Introduction: The best therapeutic option for patients with Klatskin tumors is curative resection, achieving 5-year survival rates of 20-40%. Unfortunately potentially curative resection can only be obtained in 60% of patients. It is supposed, that even incomplete resection (R1-resection) shows a significant survival benefit. In palliative situations only photodynamic therapy (PDT) could demonstrate a significant prolongation of survival. The aim of this study was to compare survival and complication rates of R1-resection of hilar cholangiocarcinoma and PDT. Patients and Methods: Patients receiving incomplete resection or palliative PDT for hilar bile duct cancer were analyzed retrospectively for survival time and complications. Patients with nonresectable bile duct cancer receiving only endoscopic stenting served as controls. Results: 32 patients in the PDT group, 21 patients in the incomplete resection group and 15 patients receiving mere endoscopic stenting were compared retrospectively. The groups did not differ significantly in gender or tumor type according to the Bismuth classification. Patients receiving resection were significantly younger (median age 62y vs. 68y) than the PDT patients. Median survival time after incomplete resection was 451 days [95% CI: 177-725], as compared to 630 days [95 CI: 385-875] after PDT (p=0,33). In contrast, median survival after endoscopic stenting alone was significantly lower with 180 days [95% CI: 83-277] (p=0,012). Major complications occurred in 50% of patients after resection, necessitating relaparotomy in 24% of patients. 30-day mortality rate was 19%, with fatal liver failure in 9,5% of patients. After PDT 30-day mortality rate was 0% and no severe phototoxicity was observed. 25% of patients developed severe bacterial cholangitis. Conclusions: Palliative PDT shows comparable survival rates to incomplete resection with significantly lower procedure related morbidity and mortality. Adjuvant PDT after incomplete resection should be evaluated in randomized controlled studies.
325 PRAJA, An E3 Ligase, May Promote Hepatocellular Carcinoma Through TGF-β Dependent Ubiquitination of ELF and SMAD3, and Via Anti-Apoptotic Activity Viveka Mishra, Rupen Amin, Geeta Upadhyay, Eric Glasgow PRAJA, a RING-H2 finger E3 ubiquitin ligase, is up-regulated in many cancers including hepatocellular carcinoma (HCC). The transforming growth factor-beta (TGF-β) signaling pathway components Smad3 and embryonic liver fodrin (ELF), a type II β-spectrin, are ubiquitinated by PRAJA in a TGF-β dependent manner. ELF, which acts as a tumor suppressor for HCC, associates with Smad3 and Smad4 to transduce TGF-β signals to the nucleus. Therefore, PRAJA, through its ability to ubiquitinate ELF and Smad3, may influence critical TGF-β functions such as tumor suppression, cell differentiation and embryonic development. Here we investigated: 1) the role of PRAJA in embryonic development by anti-PRAJA Morpholino oligonucleotide based gene knockdown studies in zebrafish; 2) the role of PRAJA in liver formation by shRNA based loss-of-function studies in liver explant cultures; and 3) the molecular interactions between ELF, Smad3 and PRAJA in the presence and absence of TGF-β pathway activation, to elucidate the mechanism of PRAJA mediated TGF-β signaling and modulation of HCC. Confocal microscopy, co-immunoprecipitation analyses, luciferase reporter assays, and fos expression were used to reveal TGF-β dependent interactions between PRAJA and ELF, and between PRAJA and Smad3. Deletion constructs of PRAJA, ELF and Smad3 were used to demonstrate that, in the presence of TGF-β, ELF and Smad3 bind to the amino-terminal fragment of PRAJA (amino acids 1-150). Furthermore, the carboxyterminal RING-H2 domain of PRAJA is required for TGF-β dependent ubiquitination of ELF and Smad3. Interestingly, loss of PRAJA function in liver explant tissue results in extensive cell death as well as activation of cartilage specific markers. Thus, PRAJA may regulate liver development, and inhibition of PRAJA could permit a switch to cartilage formation. Loss of PRAJA in zebrafish development results in a dramatic induction of apoptosis indicating that PRAJA has strong anti-apoptotic properties. In summary, these studies suggest that PRAJA promotes HCC through TGF-β dependent ubiquitination of ELF and Smad3, as well as through its anti-apoptotic activity.
323 Surgical Resection Versus Percutaneous Radiofrequency Ablation in Treatment of Hepatocellular Carcinoma: A Meta Analysis Sathya Jaganmohan, Suneal Agarwal, Krishna S. Kasturi, Gagan Sood Background: The treatment of Hepatocellular carcinoma(HCC) in patients with stage 1(single tumors < 5 cms or ≤ 3 tumors, each < 3 cms ) include liver transplantation, resection or percutaneous local ablation treatment(PLAT). If liver transplantation is not an option, surgical resection(SR) has been traditionally preferred over PLAT. Recent studies have however shown comparable results with radiofrequency ablation(RFA) and SR. We performed a meta-analysis of all randomized and observational studies comparing the overall 1 and 3 year survival rates in patients undergoing SR versus RFA. Methods: Electronic databases(MEDLINE, EMBASE and Cochrane controlled trials register) were searched(1990 to 2007) for studies comparing RFA and SR in patients with HCC. The inclusion criteria were studies that compared outcomes in patients with Child class A and stage I HCC. Studies with HCC >5 Cm, Child Class B or C and studies comparing other therapies were excluded. A total of 7 studies were identified. One study was excluded as duplication of patients was identified. The outcomes of interest were the 1 and 3 year survival rates. A meta-analysis was performed using fixed and random effects model. There was no significant publication bias as assessed by funnel plots. Results: In a total of 878 patients, 479 patients underwent RFA while 380 underwent SR. There was no statistically significant difference in the one year survival in both the groups with OR 1.132(95% CI 0.533- 2.403,p= 0.747). The three year survival rate favored surgery with OR 1.39 without statistical significance (95% CI 0.96- 2.012,p= 0.082). No significant heterogeneity was observed among published studies. Sensitivity analysis did not change the results significantly. Conclusion: For Stage I HCC in patients with Child class A, there was no difference in survival rates between treatment with RFA and surgical resection at 1 and 3 years.
366 Endoscopic Ultrasound Elastography in the Differential Diagnosis of Pancreatic Solid Masses: Towards the Virtual Biopsy Julio Iglesias-Garcia, Jose Larino-Noia, Enrique Dominguez-Munoz Endoscopic ultrasound elastography (EUS-E) allows analyzing tissue stiffness during a standard endoscopic ultrasound (EUS) examination, thus providing with additional information about the features of solid lesions. The aim of the study was to evaluate the elastographic patterns of solid pancreatic masses and the diagnostic accuracy of EUS-E in this setting. METHODS: 80 consecutive patients (mean age 62 years, 24-84 y., 54 males) who underwent EUS-E for the evaluation of solid pancreatic masses, and 10 controls with normal pancreas (mean age 59 years, 20- 83 y., 5 males), were prospectively included in the study. EUS-E was performed under conscious sedation by the linear Pentax EG 3830 UT and Hitachi EUB 8500. EUS-FNA was performed for cytological diagnosis after elastographic examination. The different elastographic patterns of solid pancreatic masses are described. Diagnostic sensitivity, specificity, PPV, NPV and overall accuracy of EUS-E for malignancy were calculated compared to final diagnosis based on cytology, histology of surgical specimens and clinical follow-up. RESULTS: Mean size of pancreatic masses was 31.7 ± 13.6 mm. Tumors were located in the head of the pancreas in 61 patients, in the body in 16 and in the tail in 3. Final diagnosis was pancreatic cancer (PC) in 48 cases, inflammatory mass (IM) in 23 patients, neuroendocrine tumor (NT) in 8 cases and metastatic tumor in 1 patient. 4 different patterns could be defined: 1) Homogeneous green, 2) heterogeneous green-predominant with yellow and red lines, 3) heterogeneous blue-predominant with a geographic appearance and green and red lines, and 4) homogeneous blue. A homogeneous green pattern was only observed in normal pancreas. 18 masses showed a heterogeneous green-predominant pattern, and all of them were IM. Thus, the probability of IM is 100% in the presence of this pattern. A heterogeneous, geographically distributed, blue-predominant pattern was found in 54 cases. This pattern was observed in all cases of malignant tumor (either PC or metastasis) and in 5 cases of IM. Thus, the probability of malignancy in the presence of this pattern is of 90.1%. A homogeneous blue pattern was exclusively seen in the 8 patients with NT. Thus, the probability of NT is 100% in the presence of this pattern. Sensitivity, specificity, PPV, NPV and overall accuracy for malignancy were 100%, 78.3%, 91.9%, 100% and 93.7% respectively. CONCLUSION: EUS-E is a very useful tool for the differential diagnosis of solid pancreatic masses. This technique adds important information to EUS evaluation by providing with highly specific patterns, which strongly support the benign or malignant nature of the disease.
324 Bone Marrow-Derived Liver-Committed Stem Cells Give Rise to Combined Hepatocholangio-Carcinomas in Rats A. Piscaglia, Thomas Shupe, Marialuisa Novi, Mariachiara Campanale, Antonio Gasbarrini, Bryon E. Petersen Background and Aims. Several studies have suggested that bipotent liver stem cells, also named “oval cells” (OCs) in rodents, may give rise to liver cancers. We have developed a new model of hepatocarcinogenesis in rats, based upon the induction of OC proliferation followed by carcinogen exposure. This regimen resulted in combined hepatocholangiocarcinomas (CHCCs), derived from initiated OCs. Several studies have proved that bone marrow (BM) liver-committed stem cells can differentiate into OCs and contribute to the hepatic regeneration. Aim of the present study was to establish if BM cells may be a source of liver tumors. Materials and Methods. Dipeptidyl-peptidase-IV (DPPIV) deficient rats received BM transplants from wild-type donors. Four weeks later, rats were subjected to the 2acetylaminofluorene/partial-hepatectomy model of OC activation, followed by the administration of aflatoxin-B1 (AFB1). A subgroup of rats was also treated with Granulocyte-Colony stimulating factor (G-CSF), to stimulate both BM mobilization and OC activation. Liver sections were analyzed by hematoxilin-eosin, immunohistochemistry, periodic acid Schiff and Masson's trichrome. DPPIV was employed as a marker of donor-derived BM cells and their progenies. Results. The hepatic remnants showed grossly apparent pale nodules, the borders of which were defined by cirrhotic-like chords, mainly consisting of OCs. The neoplasms presented a complex organization of solid trabecular and pseudo-glandular areas of degenerate hepatocytes, adjacent to large areas of dysplastic ductular cells characterized by intestinal metaplasia and cholangiofibrosis. These features were consistent with welldifferentiated CHCCs. BM-derived cells were found in the liver of all the animals, both as OCs within the chords, and as tumor-infiltrating inflammatory cells. However, a minority of CHCC nodules arose directly from BM-derived OCs. Most of the CHCC nodules expressed
367 A Prospective Randomized Back-to-Back Trial Comparing Narrow Band Imaging to Conventional Colonoscopy for Adenoma Detection Seth A. Gross, Anna M. Buchner, John R. Cangemi, Herbert C. Wolfsen, Kenneth R. DeVault, Julia Crook, Michael F. Picco, David S. Loeb, Timothy A. Woodward, Massimo Raimondo, Michael B. Wallace Background: Colonoscopy is the current gold standard to prevent colon cancer, but the overall miss rate of adenomas has been reported as high as 24%. Advances in endoscopic imaging such as high definition white light and high definition narrow band imaging (HDNBI)
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AGA Abstracts
AGA Abstracts
322
Photodynamic Therapy Versus Incomplete Resection in Hilar Cholangiocarcinoma Thomas Zoepf, Gernot M. Kaiser, Alexander Dechene, Philip A. Hilgard, Guido Gerken, Hauke Lang Introduction: The best therapeutic option for patients with Klatskin tumors is curative resection, achieving 5-year survival rates of 20-40%. Unfortunately potentially curative resection can only be obtained in 60% of patients. It is supposed, that even incomplete resection (R1-resection) shows a significant survival benefit. In palliative situations only photodynamic therapy (PDT) could demonstrate a significant prolongation of survival. The aim of this study was to compare survival and complication rates of R1-resection of hilar cholangiocarcinoma and PDT. Patients and Methods: Patients receiving incomplete resection or palliative PDT for hilar bile duct cancer were analyzed retrospectively for survival time and complications. Patients with nonresectable bile duct cancer receiving only endoscopic stenting served as controls. Results: 32 patients in the PDT group, 21 patients in the incomplete resection group and 15 patients receiving mere endoscopic stenting were compared retrospectively. The groups did not differ significantly in gender or tumor type according to the Bismuth classification. Patients receiving resection were significantly younger (median age 62y vs. 68y) than the PDT patients. Median survival time after incomplete resection was 451 days [95% CI: 177-725], as compared to 630 days [95 CI: 385-875] after PDT (p=0,33). In contrast, median survival after endoscopic stenting alone was significantly lower with 180 days [95% CI: 83-277] (p=0,012). Major complications occurred in 50% of patients after resection, necessitating relaparotomy in 24% of patients. 30-day mortality rate was 19%, with fatal liver failure in 9,5% of patients. After PDT 30-day mortality rate was 0% and no severe phototoxicity was observed. 25% of patients developed severe bacterial cholangitis. Conclusions: Palliative PDT shows comparable survival rates to incomplete resection with significantly lower procedure related morbidity and mortality. Adjuvant PDT after incomplete resection should be evaluated in randomized controlled studies.
325 PRAJA, An E3 Ligase, May Promote Hepatocellular Carcinoma Through TGF-β Dependent Ubiquitination of ELF and SMAD3, and Via Anti-Apoptotic Activity Viveka Mishra, Rupen Amin, Geeta Upadhyay, Eric Glasgow PRAJA, a RING-H2 finger E3 ubiquitin ligase, is up-regulated in many cancers including hepatocellular carcinoma (HCC). The transforming growth factor-beta (TGF-β) signaling pathway components Smad3 and embryonic liver fodrin (ELF), a type II β-spectrin, are ubiquitinated by PRAJA in a TGF-β dependent manner. ELF, which acts as a tumor suppressor for HCC, associates with Smad3 and Smad4 to transduce TGF-β signals to the nucleus. Therefore, PRAJA, through its ability to ubiquitinate ELF and Smad3, may influence critical TGF-β functions such as tumor suppression, cell differentiation and embryonic development. Here we investigated: 1) the role of PRAJA in embryonic development by anti-PRAJA Morpholino oligonucleotide based gene knockdown studies in zebrafish; 2) the role of PRAJA in liver formation by shRNA based loss-of-function studies in liver explant cultures; and 3) the molecular interactions between ELF, Smad3 and PRAJA in the presence and absence of TGF-β pathway activation, to elucidate the mechanism of PRAJA mediated TGF-β signaling and modulation of HCC. Confocal microscopy, co-immunoprecipitation analyses, luciferase reporter assays, and fos expression were used to reveal TGF-β dependent interactions between PRAJA and ELF, and between PRAJA and Smad3. Deletion constructs of PRAJA, ELF and Smad3 were used to demonstrate that, in the presence of TGF-β, ELF and Smad3 bind to the amino-terminal fragment of PRAJA (amino acids 1-150). Furthermore, the carboxyterminal RING-H2 domain of PRAJA is required for TGF-β dependent ubiquitination of ELF and Smad3. Interestingly, loss of PRAJA function in liver explant tissue results in extensive cell death as well as activation of cartilage specific markers. Thus, PRAJA may regulate liver development, and inhibition of PRAJA could permit a switch to cartilage formation. Loss of PRAJA in zebrafish development results in a dramatic induction of apoptosis indicating that PRAJA has strong anti-apoptotic properties. In summary, these studies suggest that PRAJA promotes HCC through TGF-β dependent ubiquitination of ELF and Smad3, as well as through its anti-apoptotic activity.
323 Surgical Resection Versus Percutaneous Radiofrequency Ablation in Treatment of Hepatocellular Carcinoma: A Meta Analysis Sathya Jaganmohan, Suneal Agarwal, Krishna S. Kasturi, Gagan Sood Background: The treatment of Hepatocellular carcinoma(HCC) in patients with stage 1(single tumors < 5 cms or ≤ 3 tumors, each < 3 cms ) include liver transplantation, resection or percutaneous local ablation treatment(PLAT). If liver transplantation is not an option, surgical resection(SR) has been traditionally preferred over PLAT. Recent studies have however shown comparable results with radiofrequency ablation(RFA) and SR. We performed a meta-analysis of all randomized and observational studies comparing the overall 1 and 3 year survival rates in patients undergoing SR versus RFA. Methods: Electronic databases(MEDLINE, EMBASE and Cochrane controlled trials register) were searched(1990 to 2007) for studies comparing RFA and SR in patients with HCC. The inclusion criteria were studies that compared outcomes in patients with Child class A and stage I HCC. Studies with HCC >5 Cm, Child Class B or C and studies comparing other therapies were excluded. A total of 7 studies were identified. One study was excluded as duplication of patients was identified. The outcomes of interest were the 1 and 3 year survival rates. A meta-analysis was performed using fixed and random effects model. There was no significant publication bias as assessed by funnel plots. Results: In a total of 878 patients, 479 patients underwent RFA while 380 underwent SR. There was no statistically significant difference in the one year survival in both the groups with OR 1.132(95% CI 0.533- 2.403,p= 0.747). The three year survival rate favored surgery with OR 1.39 without statistical significance (95% CI 0.96- 2.012,p= 0.082). No significant heterogeneity was observed among published studies. Sensitivity analysis did not change the results significantly. Conclusion: For Stage I HCC in patients with Child class A, there was no difference in survival rates between treatment with RFA and surgical resection at 1 and 3 years.
366 Endoscopic Ultrasound Elastography in the Differential Diagnosis of Pancreatic Solid Masses: Towards the Virtual Biopsy Julio Iglesias-Garcia, Jose Larino-Noia, Enrique Dominguez-Munoz Endoscopic ultrasound elastography (EUS-E) allows analyzing tissue stiffness during a standard endoscopic ultrasound (EUS) examination, thus providing with additional information about the features of solid lesions. The aim of the study was to evaluate the elastographic patterns of solid pancreatic masses and the diagnostic accuracy of EUS-E in this setting. METHODS: 80 consecutive patients (mean age 62 years, 24-84 y., 54 males) who underwent EUS-E for the evaluation of solid pancreatic masses, and 10 controls with normal pancreas (mean age 59 years, 20- 83 y., 5 males), were prospectively included in the study. EUS-E was performed under conscious sedation by the linear Pentax EG 3830 UT and Hitachi EUB 8500. EUS-FNA was performed for cytological diagnosis after elastographic examination. The different elastographic patterns of solid pancreatic masses are described. Diagnostic sensitivity, specificity, PPV, NPV and overall accuracy of EUS-E for malignancy were calculated compared to final diagnosis based on cytology, histology of surgical specimens and clinical follow-up. RESULTS: Mean size of pancreatic masses was 31.7 ± 13.6 mm. Tumors were located in the head of the pancreas in 61 patients, in the body in 16 and in the tail in 3. Final diagnosis was pancreatic cancer (PC) in 48 cases, inflammatory mass (IM) in 23 patients, neuroendocrine tumor (NT) in 8 cases and metastatic tumor in 1 patient. 4 different patterns could be defined: 1) Homogeneous green, 2) heterogeneous green-predominant with yellow and red lines, 3) heterogeneous blue-predominant with a geographic appearance and green and red lines, and 4) homogeneous blue. A homogeneous green pattern was only observed in normal pancreas. 18 masses showed a heterogeneous green-predominant pattern, and all of them were IM. Thus, the probability of IM is 100% in the presence of this pattern. A heterogeneous, geographically distributed, blue-predominant pattern was found in 54 cases. This pattern was observed in all cases of malignant tumor (either PC or metastasis) and in 5 cases of IM. Thus, the probability of malignancy in the presence of this pattern is of 90.1%. A homogeneous blue pattern was exclusively seen in the 8 patients with NT. Thus, the probability of NT is 100% in the presence of this pattern. Sensitivity, specificity, PPV, NPV and overall accuracy for malignancy were 100%, 78.3%, 91.9%, 100% and 93.7% respectively. CONCLUSION: EUS-E is a very useful tool for the differential diagnosis of solid pancreatic masses. This technique adds important information to EUS evaluation by providing with highly specific patterns, which strongly support the benign or malignant nature of the disease.
324 Bone Marrow-Derived Liver-Committed Stem Cells Give Rise to Combined Hepatocholangio-Carcinomas in Rats A. Piscaglia, Thomas Shupe, Marialuisa Novi, Mariachiara Campanale, Antonio Gasbarrini, Bryon E. Petersen Background and Aims. Several studies have suggested that bipotent liver stem cells, also named “oval cells” (OCs) in rodents, may give rise to liver cancers. We have developed a new model of hepatocarcinogenesis in rats, based upon the induction of OC proliferation followed by carcinogen exposure. This regimen resulted in combined hepatocholangiocarcinomas (CHCCs), derived from initiated OCs. Several studies have proved that bone marrow (BM) liver-committed stem cells can differentiate into OCs and contribute to the hepatic regeneration. Aim of the present study was to establish if BM cells may be a source of liver tumors. Materials and Methods. Dipeptidyl-peptidase-IV (DPPIV) deficient rats received BM transplants from wild-type donors. Four weeks later, rats were subjected to the 2acetylaminofluorene/partial-hepatectomy model of OC activation, followed by the administration of aflatoxin-B1 (AFB1). A subgroup of rats was also treated with Granulocyte-Colony stimulating factor (G-CSF), to stimulate both BM mobilization and OC activation. Liver sections were analyzed by hematoxilin-eosin, immunohistochemistry, periodic acid Schiff and Masson's trichrome. DPPIV was employed as a marker of donor-derived BM cells and their progenies. Results. The hepatic remnants showed grossly apparent pale nodules, the borders of which were defined by cirrhotic-like chords, mainly consisting of OCs. The neoplasms presented a complex organization of solid trabecular and pseudo-glandular areas of degenerate hepatocytes, adjacent to large areas of dysplastic ductular cells characterized by intestinal metaplasia and cholangiofibrosis. These features were consistent with welldifferentiated CHCCs. BM-derived cells were found in the liver of all the animals, both as OCs within the chords, and as tumor-infiltrating inflammatory cells. However, a minority of CHCC nodules arose directly from BM-derived OCs. Most of the CHCC nodules expressed
367 A Prospective Randomized Back-to-Back Trial Comparing Narrow Band Imaging to Conventional Colonoscopy for Adenoma Detection Seth A. Gross, Anna M. Buchner, John R. Cangemi, Herbert C. Wolfsen, Kenneth R. DeVault, Julia Crook, Michael F. Picco, David S. Loeb, Timothy A. Woodward, Massimo Raimondo, Michael B. Wallace Background: Colonoscopy is the current gold standard to prevent colon cancer, but the overall miss rate of adenomas has been reported as high as 24%. Advances in endoscopic imaging such as high definition white light and high definition narrow band imaging (HDNBI)
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AGA Abstracts
AGA Abstracts
322