ABSTRACT Background: This manuscript provides an overview of liver carcinogenesis in murine models of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). Objective: A review through MEDLINE and EMBASE was performed to assess articles until August 2022. Methods: Search was conducted of the entire electronic databases and the keywords used was HCC, CCA, carcinogenesis, animal models and liver. Articles exclusion was based on the lack of close relation to the subject. Carcinogenesis models of HCC include HCC induced by senescence in transgenic animals, HCC diet-induced, HCC induced by chemotoxicagents, xenograft, oncogenes, and HCC in transgenic animals inoculated with B and C virus. The models of CCA include the use of dimethylnitrosamine (DMN), diethylnitrosamine (DEN), thioacetamide (TAA), and carbon tetrachloride (CCl4). CCA murine models may also be induced by: CCA cells, genetic manipulation, Smad4, PTEN and p53 knockout, xenograft, and DEN-left median bile duct ligation. Results: In this review, we described different murine models of carcinogenesis that reproduce the key points for HCC and CCA genesis allowing a better understanding of its genetic, physiopathological, and environmental abnormalities. Conclusion: Each model has its advantages, disadvantages, similarities, and differences with the corresponding human disease and should be chosen according to the specificity of the study. Ultimately, those models can also be used for testing new anticancer therapeutic approaches.

RESUMO Contexto: Este manuscrito fornece uma visão geral da carcinogênese hepática em modelos murinos de carcinoma hepatocelular (CHC) e colangiocarcinoma (CCA). Objetivo: Realizar uma revisão de artigos científicos até agosto de 2022 utilizando as bases de dados MEDLINE e EMBASE. Métodos: A busca foi realizada em todas as bases de dados eletrônicas e as palavras-chave usadas foram CHC, CCA, carcinogenesis, modelos animais e fígado. A exclusão dos artigos baseou-se na falta de estreita relação com o assunto. Os modelos de carcinogênese do CHC incluíram: CHC induzido por senescência em animais transgênicos, CHC induzido por dieta, CHC induzido por agentes quimiotóxicos, xenoenxerto, oncogenes e CHC em animais transgênicos inoculados com vírus B e C. Os modelos de CCA incluíram: o uso de dimetilnitrosamina (DMN), dietilnitrosamina (DEN), tioacetamida (TAA) e tetracloreto de carbono (CCl4). Os modelos murinos de CCA induzidos por incluir: células de CCA, manipulação genética, animais nocaute para Smad4, PTEN e p53, xenoenxerto e ligadura do ducto biliar mediano esquerdo. Resultados: Nesta revisão, descrevemos diferentes modelos murinos de carcinogênese que reproduzem os pontos-chave para a gênese do CHC e do CCA, permitindo uma melhor compreensão de suas anormalidades genéticas, fisiopatológicas e ambientais. Conclusão: Cada modelo tem suas vantagens, desvantagens, semelhanças e diferenças com a doença humana correspondente e deve ser escolhido de acordo com a especificidade do estudo. Em última análise, esses modelos também podem ser utilizados para testar novas abordagens terapêuticas anticancerígenas.

ABSTRACT BACKGROUND: After validation in multiple types of liver disease patients, the MELD score was adopted as a standard by which liver transplant candidates with end-stage liver disease were prioritized for organ allocation in the United States since 2002, and in Brazil, since 2006. AIMS: To analyze the mortality profile of patients on the liver transplant waiting list correlated to MELD score at the moment of transplantation. METHODS: This study used the data from the Secretary of Health of the São Paulo State, Brazil, which listed 22,522 patients, from 2006 (when MELD score was introduced in Brazil) until June 2009. Patients with acute hepatic failure and tumors were included as well. We also considered the mortality of both non-transplanted and transplanted patients as a function of the MELD score at presentation. RESULTS: Our model showed that the best MELD score for patients on the liver transplant waiting list associated to better results after liver transplantation was 26. CONCLUSIONS: We found that the best score for applying to liver transplant waiting list in the State of São Paulo was 26. This is the score that minimizes the mortality in both non-transplanted and liver transplanted patients.

RESUMO RACIONAL: Desde 2002, após validação em múltiplos tipos de hepatopatias, o escore MELD foi adotado como padrão pelo qual os candidatos a transplante de fígado com doença hepática terminal têm sido priorizados para alocação de órgãos nos Estados Unidos, e em 2006 no Brasil. OBJETIVOS: Analisar a mortalidade de pacientes em lista de espera para transplante de fígado correlacionando com o MELD, no momento do transplante. MÉTODOS: Foram utilizados os dados da Secretaria de Saúde do Estado de São Paulo, Brasil, onde foram listados 22.522 pacientes, desde 2006 (quando o escore MELD foi introduzido no Brasil) até junho de 2009. Foram incluídos pacientes com falência hepática e tumores. A mortalidade de pacientes não transplantados e transplantados também foi considerada em função do escore MELD. RESULTADOS: Nosso modelo mostrou que o melhor valor do MELD, em pacientes em lista de espera para transplante e com melhores resultados, foi de 26. Este valor minimiza mortalidade em pacientes não transplantados bem comem pacientes na lista de espera para transplante de fígado. CONCLUSÕES: O escore MELD ótimo para entrar na lista de espera para transplante de fígado, no estado de São Paulo, é em torno de 26. Esse é o valor que minimiza a mortalidade tanto dos pacientes não transplantados em lista de espera, quanto dos submetidos à transplante de fígado.

ABSTRACT BACKGROUND: The main treatment modality for gastric cancer is surgical resection with lymphadenectomy. Despite advances in perioperative care, major surgical complications can occur in up to 20% of cases. To determine the quality of surgical care employed, a new indicator called failure to rescue (FTR) was proposed, which assesses the percentage of patients who die after complications occur. AIMS: To assess the rate of FTR after gastrectomy and factors associated with its occurrence. METHODS: Patients with gastric cancer who underwent gastrectomy with curative intent were retrospectively evaluated. According to the occurrence of postoperative complications, patients were divided into FTR group (grade V complications) and rescued group (grade III/IV complications). RESULTS: Among the 731 patients, 114 had major complications. Of these patients, 76 (66.7%) were successfully treated for the complication (rescued group), while 38 (33.3%) died (FTR group). Patients in the FTR group were older (p=0.008; p<0.05), had lower levels of hemoglobin (p=0.021; p<0.05) and albumin (p=0.002; p<0.05), and a higher frequency of ASA III/IV (p=0.033; p<0.05). There were no differences between the groups regarding surgical and pathological characteristics. Clinical complications had a higher mortality rate (40.0% vs 30.4%), with pulmonary complications (50.2%) and infections (46.2%) being the most lethal. Patients with major complications grade III/IV had worse survival than those without complications. CONCLUSIONS: The FTR rate was 33.3%. Advanced age, worse performance, and nutritional parameters were associated with FTR.

RESUMO RACIONAL: A principal modalidade de tratamento do câncer gástrico (CG) é a ressecção cirúrgica associada a linfadenectomia. Apesar dos avanços no cuidado peri-operatório, as complicações cirúrgicas maiores podem ocorrer em até 20% dos casos. Para determinar a qualidade do atendimento cirúrgico empregado, foi proposto um novo indicador denominado failure to rescue (FTR), que avalia a porcentagem dos pacientes que vão a óbito após a ocorrência de complicações. OBJETIVOS: Avaliar a taxa de FTR após gastrectomia e fatores associados com a sua ocorrência. MÉTODOS: Foram avaliados retrospectivamente os pacientes com CG submetidos à gastrectomia com intenção curativa. De acordo com a ocorrência de complicações pós-operatórias, os pacientes foram divididos em grupo FTR (complicação grau V) e grupo resgatado (complicações grau 3-4). RESULTADOS: Entre os 731 pacientes, 114 tiveram maiores complicações. Desses pacientes, 76 casos (66,7%) obtiveram sucesso no tratamento da complicação (grupo resgatados), enquanto 38 casos (33,3%) foram a óbito (grupo FTR). Os pacientes do grupo FTR apresentaram idade mais avançada (p=0,008, p<0,05), menores níveis de hemoglobina (p=0,021, p<0,05) e de albumina (p=0,002, p<0,05), e maior frequência de ASA III/IV (p=0,033, p<0,05). Não houve diferença entre os grupos quanto às características cirúrgicas e patológicas. As complicações clínicas apresentaram maior taxa de mortalidade (40.0% vs 30,4%), sendo complicações pulmonares (50,2%) e infecções (46,2%) as mais letais. Pacientes com complicações maiores grau III-IV tiveram pior sobrevida comparado aqueles sem complicações. CONCLUSÕES: A taxa de FTR foi de 33,3%. Idade avançada, pior performance, e parâmetros nutricionais associam-se ao FTR.

ABSTRACT Ischemia-reperfusion injury is a pathophysiological event occuring after abdominal organ transplantation, and has a significant influence on prognosis and survival of the graft. It is involved in delaying the primary function or non-functioning of the graft. The objective of this study was to provide information on heat shock protein mechanisms in ischemia-reperfusion injuries in abdominal organ transplantations, and to indicate the possible factors involved that may influence the graft outcome. Several classes of heat shock proteins are part of the ischemia and reperfusion process, both as inflammatory agonists and in protecting the process. Studies involving heat shock proteins enhance knowledge on ischemia-reperfusion injury mitigation processes and the mechanisms involved in the survival of abdominal grafts, and open space to support therapeutic future clinical studies, minimizing ischemia and reperfusion injuries in abdominal organ transplantations. Expression of heat shock proteins is associated with inflammatory manifestations and ischemia-reperfusion injuries in abdominal organ transplantations and may influence graft outcomes.

ABSTRACT Introduction: Portal hypertension still represents an important health problem worldwide. In the search for knowledge regarding this syndrome, experimental studies with animal models have proven to be useful to point the direction to be taken in future randomized clinical trials. Purpose: To validate the experimental model of portal hypertension and esophagogastric varices in a medium-sized animal. Methods: This study included five minipigs br1. Midline laparotomy with dissection of the portal vein and production of a calibrated stenosis of this vein was performed. Measurement of pressure in the portal venous and digestive endoscopic were performed before and five weeks after the production of a stenosis. Results: All animals were 8 months old, average weight of 17 ± 2.5 kg. The mean pressure of the portal vein immediately before the partial ligation of the portal vein was 8.9 + 1.6 mm Hg, with 26.6 + 5.4 mm Hg in the second measurement five weeks later (p < 0.05). No gastroesophageal varices or hypertensive portal gastropathy were seen at endoscopy procedures in our sample at any time in the study. Conclusion: Portal vein ligation in minipigs has been validated in the production of portal hypertension, but not in the formation of esophageal varices.

Abstract Objectives: To evaluate results of patients undergoing liver resection in a single center over the past two decades with a particular look at Colorectal Liver Metastasis (CRLM) and Hepatocellular Carcinoma (HCC). Method: Patients were divided into two eras, from 2000 to 2010 (Era 1) and 2011 to 2020 (Era 2). The most frequent diagnosis was CRLM and HCC, with 738 (52.4%) and 227 (16.1%) cases respectively. An evaluation of all liver resection cases and a subgroup analysis of both CRLM and HCC were performed. Preoperative and per operative variables and long-term outcomes were evaluated. Results: 1409 liver resections were performed. In Era 2 the authors observed higher BMI, more: minimally invasive surgeries, Pringle maneuvers, and minor liver resections; and less transfusion, less ICU necessity, and shorter length of hospital stay. Severe complications were observed in 14.7% of patients, and 90-day mortality was 4.2%. Morbidity and mortality between eras were not different. From 738 CRLM resections, in Era 2 there were significantly more patients submitted to neoadjuvant chemotherapy, bilateral metastases, and smaller sizes with significantly less transfusion, the necessity of ICU, and shorter length of hospital stay. More pedicle clamping, minimally invasive surgeries, and minor resections were also observed. From 227 HCC resections, in Era 2 significantly more minimally invasive surgeries, fewer transfusions, less necessity of ICU, and shorter length of hospital stay were observed. OS was not different between eras for CRLM and HCC. Conclusions: Surgical resection in a multidisciplinary environment remains the cornerstone for the curative treatment of primary and metastatic liver tumors.

RESUMO - RACIONAL: O câncer colorretal é a terceira neoplasia mais frequente e metade dos pacientes desenvolvem metástase hepática. O melhor fator prognóstico na metástase hepática de câncer colorretal (MHCCR) é a possibilidade de ressecção com margens livres, porém a maioria permanece irressecável. O racional em realizar transplante hepático (TH) em pacientes portadores de MHCCR está na ampliação do número de pacientes ressecáveis através de uma hepatectomia total. OBJETIVO: Apresentar protocolo brasileiro para realização de transplante hepático em pacientes com MHCCR irressecável. MÉTODO: O protocolo foi realizado por duas instituições com grande volume de ressecções e transplantes hepáticos no Brasil, baseado no trabalho realizado pela Universidade de Oslo. A elaboração foi dividida em 4 etapas. RESULTADO: É apresentada proposta de protocolo para esta doença a ser validada na aplicação clínica. CONCLUSÃO: Foi possível elaborar protocolo de transplante hepático para MHCCR irressecável a fim de uniformizar o tratamento e melhor avaliar os resultados cirúrgicos.

ABSTRACT - BACKGROUND: Colorectal cancer (CRC) is the third most common neoplasm, and half of the patients with CRC develop liver metastasis. The best prognostic factor for colorectal liver metastasis (CRLM) is the possibility of performing a resection with free margins; however, most of them remain unresectable. The justification for performing liver transplantation (LT) in patients with CRLM regards an increase in the number of resectable patients by performing total hepatectomy. AIM: The aim of this study was to provide a Brazilian protocol for LT in patients with unresectable CRLM. METHOD: The protocol was carried out by two Brazilian institutions, which perform a large volume of resections and LTs, based on the study carried out at the University of Oslo. The elaboration of the protocol was conducted in four stages. RESULT: A protocol proposal for this disease is presented, which needs to be validated for clinical use. CONCLUSION: The development of an LT protocol for unresectable CRLM aims to standardize the treatment and to enable a better evaluation of surgical results.

RESUMO Racional: O colangiocarcinoma hilar representa mais da metade de todos os casos de colangiocarcinoma; tem prognóstico reservado e sobrevida global mediana de 12- 24 meses após o diagnóstico. A proposta de realizar transplante hepático surgiu para ampliar a possibilidade de margens livres através de hepatectomia total nos portadores de tumoresirressecáveis com melhor prognóstico. Objetivo: Apresentar protocolo brasileiro para realização de transplante hepático em pacientes com colangiocarcinoma hilar. Método: O protocolo foi realizado por duas instituições com grande volume de ressecções e transplantes hepáticos no Brasil, baseado no trabalho realizado pela MayoClinic. A elaboração foi dividida em quatro etapas. Resultado: É apresentada proposta de protocolo para esta doença a ser validada na aplicação clínica. Conclusão: Foi possível elaborar protocolo de transplante hepático para colangiocarcinoma a fim de uniformizar o tratamento e melhor avaliar os resultados cirúrgicos.

ABSTRACT Background: Hilar cholangiocarcinoma represents more than half of all cholangiocarcinoma cases, having poor prognosis and presenting a median overall survival after diagnosis of 12-24 months. In patients who have unresectable tumors with a better prognosis, the proposal to perform liver transplantation emerged for expanding the possibility of free margins by performing total hepatectomy. Aim: To provide a Brazilian protocol for liver transplantation in patients with hilar cholangiocarcinoma. Method: The protocol was carried out by two Brazilian institutions which perform a large volume of resections and liver transplantations, based on the study carried out at the Mayo Clinic. The elaboration of the protocol was conducted in four stages. Result: A protocol proposal for this disease is presented, which needs to be validated for clinical use. Conclusion: The development of a liver transplantation protocol for cholangiocarcinoma aims not only to standardize the treatment, but also enable a better assessment of the surgical results in the future.

OBJECTIVE: With the increasing prevalence of steatosis, the number of steatotic liver grafts from deceased donors is also increasing. Thus, determining the prevalence and the population risk factors of steatosis may assist in risk stratification. The aim of this study was to evaluate the prevalence and predictors of steatosis and steatohepatitis among livers from adults who died due to non-burn trauma. METHODS: Specimens were collected from 224 adults undergoing autopsy at a regional autopsy referral center from September 2011 to April 2013. Histopathological examination was performed on six samples obtained from different lobes of each liver. The outcomes of interest were the presence of steatosis, steatohepatitis, NASH inflammation and NASH fibrosis. The main predictors were body mass index, abdominal circumference, liver weight and volume, presence of cholelithiasis, and siderosis. Our modeling strategy made use of a series of generalized linear models with a binomial family. RESULTS: Our sample had a mean age of 40 years; steatosis was diagnosed in 48.2% of cases, and steatohepatitis was diagnosed in 2.7%. The presence of a high proportion of fatty changes was more prevalent among males and older individuals, with the most affected age group being 41-60 years. When evaluating the crude odds ratio for steatosis, the factors significantly associated with an increased risk of steatosis were greater abdominal circumference, BMI, and liver weight and the presence of siderosis. CONCLUSION: Our study reinforces the role of older age, obesity and hepatomegaly as predictors of fatty liver disease. These variables should be considered in the assessment of fatty changes in the livers of potential liver donors.

Abstract Purpose: To analyze the effect of methylene blue (MB) therapy during the liver ischemia-reperfusion injury (I/R) process. Methods: Thirty-five male Wistar rats were used, (70%) submitted to partial ischemia (IR) or not (NIR) (30%) were obtained from the same animal. These animals were divided into six groups: 1) Sham (SH), 2) Sham with MB (SH-MB); 3) I/R, submitted to 60 minutes of partial ischemia and 15 minutes of reperfusion; 4) NI/R, without I/R obtained from the same animal of group I/R; 5) I/R-MB submitted to I/R and MB and 6) NI/R-MB, without I/R. Mitochondrial function was evaluated. Osmotic swelling of mitochondria as well as the determination of malondialdehyde (MDA) was evaluated. Serum (ALT/AST) dosages were also performed. MB was used at the concentration of 15mg/kg, 15 minutes before hepatic reperfusion. Statistical analysis was done by the Mann Whitney test at 5%. Results: State 3 shows inhibition in all ischemic groups. State 4 was increased in all groups, except the I/R-MB and NI/R-MB groups. RCR showed a decrease in all I/R and NI/R groups. Mitochondrial osmotic swelling showed an increase in all I/R NI/R groups in the presence or absence of MB. About MDA, there was a decrease in SH values in the presence of MB and this decrease was maintained in the I/R group. AST levels were increased in all ischemic with or without MB. Conclusions: The methylene blue was not able to restore the mitochondrial parameters studied. Also, it was able to decrease lipid peroxidation, preventing the formation of reactive oxygen species.

Abstract Purpose: To evaluate whether pre-treatment with rivastigmine is able to attenuate the I/R induced lesions in rat liver. Methods: SHAM animals or those submitted to I/R, non-treated or pre-treated with rivastigminine (2mg/kg) either 50 or 15 minutes before ischemia, were used. After I/R protocol, these animals were killed and their livers were harvested to measurement of the mitochondrial swelling as well as the malondialdehyde (MDA), nitrite and nitrate tissue concentration. Blood was also harvested for serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) determinations. Results: I/R promoted a significant increase of mitochondrial swelling in the studied animals. This increase of mitochondrial swelling was partially prevented by rivastigmine, but only if administered 50 minutes before ischemia. No significant modification of MDA, nitrite or nitrate tissue concentrations was observed in consequence of I/R, followed or not by rivastigmine treatments. In addition, I/R elevated both AST and ALT. These elevations of serum enzymes were not reversed by the different rivastigmine treatments. Conclusions: Rivastigmine administered 50 minutes before ischemia attenuates I/R-induced mitochondrial swelling, that indicates liver injury. This protective effect may be related to a greater stimulation of α7nAChR present in the Kupffer cells by the non-methabolized ACh, leading to an attenuation of I/R-induced inflammation.

Abstract It is well known that during hepatic operative procedures, it is often critical that the irrigation is interrupted to avoid possible bleeding, blood transfusions, variable intensities, and their short and long-term consequences. It was believed in the past that the flow interruption should not exceed 20 minutes, which limited the use of this maneuver. However, it has been postulated that ischemia could be maintained for more than 60 minutes in healthy livers. The present paper review includes: 1) A brief introduction to justify the rationale of the review design; 2) Aspects of the pathophysiology of the three stages of the liver ischemia-reperfusion injury; 3) The innate and acquired immunity; 4) Oxidative stress; 5) Apoptosis and autophagy, Some essential biomarkers (Tumor Necrosis Factor-α, nitric oxide, metalloproteinases); and, finally; 6) Preventive (“cheating”) strategies, non-pharmacological and pharmacological options to treat the liver IR injury.

OBJECTIVES: The objective of the present study was to evaluate the protective effect of pre-conditioning treatment with laser light on hepatic injury in rats submitted to partial ischemia using mitochondrial function and liver fatty acid binding protein as markers. METHODS: Rats were divided into four groups (n=5): 1) Control, 2) Control + Laser, 3) Partial Ischemia and 4) Partial Ischemia + Laser. Ischemia was induced by clamping the hepatic pedicle of the left and middle lobes of the liver for 60 minutes. Laser light at 660 nm was applied to the liver immediately prior to the induction of ischemia at 22.5 J/cm2, with 30 seconds of illumination at five individual points. The animals were sacrificed after 30 minutes of reperfusion. Blood and liver tissues were collected for analysis of mitochondrial function, determination of malondialdehyde and analysis of fatty acid binding protein expression by Western blot. RESULTS: Mitochondrial function decreased in the Partial Ischemia group, especially during adenosine diphosphate-activated respiration (state 3), and the expression of fatty acid binding protein was also reduced. The application of laser light prevented bioenergetic changes and restored the expression of fatty acid binding protein. CONCLUSION: Prophylactic application of laser light to the livers of rats submitted to partial ischemia was found to have a protective effect in the liver, with normalization of both mitochondrial function and fatty acid binding protein tissue expression.