Grzegorz Niewiński

Next generation sequencing reveals microRNA isoforms in liver cirrhosis and hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents the major histological subtype of liver cancer. Tumorigenic changes in hepatic cells potentially result from aberrant expression of microRNAs (miRNAs). Individual microRNA gene may give rise to miRNAs of different length, named isomiRNAs that proved to be functionally relevant. Since microRNA length heterogeneity in hepatic tissue has not been described before, we employed next-generation sequencing to comprehensively analyze microRNA transcriptome in HCC tumors (n=24) and unaffected tissue adjacent to tumors (n=24), including samples with (n=15) and without cirrhosis (n=9). We detected 374 microRNAs expressed in liver, including miR-122-5p that constituted over 39% of the hepatic miRnome. Among the liver expressed miRs, the levels of 64 significantly differed between tumor and control samples (FDR<0.05, fold change>2). Top deregulated miRNAs included miR-1269a (T/N=22.95), miR-3144-3p (T/N=5.24), miR-183-5p (T/N=4.63), miR-10b-5p (T/N=3.87), miR-490-3p (T/N=0.13), miR-199a-5p (T/N=0.17), miR-199a-3p/miR-199b-3p (T/N=0.19), miR-214-5p (T/N=0.20) and miR-214-3p (T/N=0.21). Almost all miRNA genes produced several mature molecules differing in length (isomiRNAs). The reference sequence was not the most prevalent in 38.6% and completely absent in 10.5% of isomiRNAs. Over 26.1% of miRNAs produced isoforms carrying≥2 alternative seed regions, of which 35.5% constituted novel, previously unknown seeds. This fact sheds new light on the percentage of the human genome regulated by microRNAs and their variants. Among the most deregulated miRNAs, miR-199a-3p/miR-199b-3p (T/N fold change=0.18, FDR=0.005) was expressed in 9 isoforms with 3 different seeds, concertedly leading to upregulation of TGF-beta signaling pathway (OR=1.99; p=0.004). In conclusion, the study reveals the comprehensive miRNome of hepatic tissue and provides new tools for investigation of microRNA-dependent pathways in cirrhotic liver and hepatocellular carcinoma. This article is part of a Directed Issue entitled: Rare Cancers.

1000 liver transplantations at the Department of General, Transplant and Liver Surgery, Medical University of Warsaw--analysis of indications and results.

THE AIM OF THE STUDY was to analyze indications and results of the first one thousand liver transplantations at Chair and Clinic of General, Transplantation and Liver Surgery, Medical University of Warsaw. MATERIAL AND METHODS Data from 1000 transplantations (944 patients) performed at Chair and Clinic of General, Transplantation and Liver Surgery between 1994 and 2011 were analyzed retrospectively. These included 943 first transplantations and 55 retransplantations and 2 re-retransplantations. Frequency of particular indications for first transplantation and retransplantations was established. Perioperative mortality was defined as death within 30 days after the transplantation. Kaplan-Meier survival analysis was used to estimate 5-year patient and graft survival. RESULTS The most common indications for first transplantation included: liver failure caused by hepatitis C infection (27.8%) and hepatitis B infection (18%) and alcoholic liver disease (17.7%). Early (< 6 months) and late (> 6 months) retransplantations were dominated by hepatic artery thrombosis (54.3%) and recurrence of the underlying disease (45%). Perioperative mortality rate was 8.9% for first transplantations and 34.5% for retransplantations. Five-year patient and graft survival rate was 74.3% and 71%, respectively, after first transplantations and 54.7% and 52.9%, respectively, after retransplantations. CONCLUSIONS Development of liver transplantation program provided more than 1000 transplantations and excellent long-term results. Liver failure caused by hepatitis C and B infections remains the most common cause of liver transplantation and structure of other indications is consistent with European data.

Prognostic scoring systems for mortality in intensive care units — the APACHE model

The APACHE (Acute Physiology and Chronic Health Evaluation) scoring system is time consuming. The mean time for introducing a patients data to APACHE IV is 37.3 min. Nevertheless, statisticians have known for years that the higher the number of variables the mathematical model describes, the more accurate the model. Because of the necessity of gathering data over a 24-hour period and of determining one cause for ICU admission, the system is troublesome and prone to mistakes. The evolution of the APACHE scoring system is an example of unfulfilled hopes for accurately estimating the risk of death for patients admitted to the ICU; satisfactory prognostic effects resulting from the use of APACHE II and III have been recently studied in patients undergoing liver transplantations. Because no increase in the predictive properties of successive versions has been observed, the search for other solutions continues. The APACHE IV scoring system is helpful; however, its use without prepared spreadsheets is almost impractical. Therefore, although many years have passed since its original publication, APACHE II or its extension APACHE III is currently used in clinical practice.

Evolution Of The Results Of 1500 Liver Transplantations Performed In The Department Of General, Transplant And Liver Surgery Medical University Of Warsaw.

UNLABELLED Liver transplantation is a well-established treatment of patients with end-stage liver disease and selected liver tumors. Remarkable progress has been made over the last years concerning nearly all of its aspects. The aim of this study was to evaluate the evolution of long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery (Medical University of Warsaw). MATERIAL AND METHODS Data of 1500 liver transplantations performed between 1989 and 2014 were retrospectively analyzed. Transplantations were divided into 3 groups: group 1 including first 500 operations, group 2 including subsequent 500, and group 3 comprising the most recent 500. Five year overall and graft survival were set as outcome measures. RESULTS Increased number of transplantations performed at the site was associated with increased age of the recipients (p<0.001) and donors (p<0.001), increased rate of male recipients (p<0.001), and increased rate of piggyback operations (p<0.001), and decreased MELD (p<0.001), as well as decreased blood (p=0.006) and plasma (p<0.001) transfusions. Overall survival was 71.6% at 5 years in group 1, 74.5% at 5 years in group 2, and 85% at 2.9 years in group 3 (p=0.008). Improvement of overall survival was particularly observed for primary transplantations (p=0.004). Increased graft survival rates did not reach the level of significance (p=0.136). CONCLUSIONS Long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery are comparable to those achieved in the largest transplant centers worldwide and are continuously improving despite increasing recipient age and wider utilization of organs procured from older donors.

Innate immunity gene expression changes in critically ill patients with sepsis and disease-related malnutrition

The aim of this study was an attempt to determine whether the expression of genes involved in innate antibacterial response (TL R2, NOD 1, TRAF6, HMGB 1 and Hsp70) in peripheral blood leukocytes in critically ill patients, may undergo significant changes depending on the severity of the infection and the degree of malnutrition. The study was performed in a group of 128 patients with infections treated in the intensive care and surgical ward. In 103/80.5% of patients, infections had a severe course (sepsis, severe sepsis, septic shock, mechanical ventilation of the lungs). Clinical monitoring included diagnosis of severe infection (according to the criteria of the ACC P/SCC M), assessment of severity of the patient condition and risk of death (APACHE II and SAPS II), nutritional assessment (NRS 2002 and SGA scales) and the observation of the early results of treatment. Gene expression at the mRNA level was analyzed by real-time PCR. The results of the present study indicate that in critically ill patients treated in the IC U there are significant disturbances in the expression of genes associated with innate antimicrobial immunity, which may have a significant impact on the clinical outcome. The expression of these genes varies depending on the severity of the patient condition, severity of infection and nutritional status. Expression disorders of genes belonging to innate antimicrobial immunity should be diagnosed as early as possible, monitored during the treatment and taken into account during early therapeutic treatment (including early nutrition to support the functions of immune cells).

The impact of experience of a transplantation center on the outcomes of orthotopic liver transplantation

The so-called learning factor has been disregarded for many years in analyzing the causes of surgical complications and post-operative mortality; it is also the case for OLT. In our center until April 2003, 209 OLT were performed in 196 patients. We evaluated the impact of experience of the transplantation team on the outcomes of liver transplantation. Thirty-four patients died (mortality rate, 16%) and 1-year survival rate, 64%. Mortality rates varied during different periods of observation due to increasing experience of the transplantation team. The causes of mortality were assessed for a series of 34 patients: it was 75% at the beginning of transplantation procedures while recent deaths have not recently exceeded 10% of cases.

Perioperative bleeding in patients undergoing liver transplantation

Liver transplantation (LT) remains one of the most challenging surgical procedures. For many years uncontrolled bleeding and catastrophic haemorrhages were one of the major causes of perioperative mortality and morbidity. During the past fifty years or so, significant progress in surgical techniques and perioperative management has led to a marked change in transfusion practice over time, where up to 79.6% of LTs in experienced transplant centers are performed without any blood product transfusion. Despite this, perioperative bleeding and transfusion requirements remain potent predictors of patients mortality, as well as postoperative complications and graft survival. The major impact of blood product transfusion on LT recipient outcomes implies that all patients on waiting lists should be carefully screened for the presence of risk factors of perioperative bleeding. Although multiple predictors of transfusion requirements during LT have been identified, no predictive model validated across centers has been constructed. The most suitable strategies to reduce intraoperative blood loss in this group should be employed on a case-to-case basis. This paper aims to summarize the most up-to-date evidence in the management of haemostasis in LT recipients.

Severe gestational hyperthyroidism complicated by cardiac arrest — a case report

Alina Kuryłowicz1, Grzegorz Niewiński2, Andrzej Kański2, Paweł Derlatka3, Krzysztof Czajkowski3, Tomasz Bednarczuk1, Urszula Ambroziak1 1Department of Internal Medicine and Endocrinology, Medical University of Warsaw, Poland 22nd Department of Anesthesiology and Intensive Therapy, Medical University of Warsaw, Poland 32nd Department of Obstetrics and Gynecology, Medical University of Warsaw, Poland

A rare but life-threatening complication in liver transplant recipients

Graft versus host disease (GvHD) occurs in as little as 1–2% of cases after liver transplantation (LT), but is probably under-diagnosed and under-reported. Skin rash, diarrhoea, and/or fever are early symptoms of GvHD, and the most common causes of death are sepsis or gastrointestinal bleeding as a result of bone-marrow involvement. The delay in diagnosis as well as lack of standard treatment contributes to the high lethality of GvHD.

Impact of genetic polymorphism on perioperative bleeding in adult patients undergoing liver transplantation

Intr Perioperative bleeding remains one of the major causes of increased mortality and morbidity in patients (pts) undergoing liver transplantation (LT). Only few studies have examined the association between genetic polymorphisms and increased blood loss in the population of surgical pts. There are no data regarding this issue neither in liver nor in any other solid organ transplant recipients.