Magnus Rizell

A prospective randomised, open-labeled, trial comparing sirolimus-containing versus mTOR-inhibitor-free immunosuppression in patients undergoing liver transplantation for hepatocellular carcinoma

BackgroundThe potential anti-cancer effects of mammalian target of rapamycin (mTOR) inhibitors are being intensively studied. To date, however, few randomised clinical trials (RCT) have been performed to demonstrate anti-neoplastic effects in the pure oncology setting, and at present, no oncology endpoint-directed RCT has been reported in the high-malignancy risk population of immunosuppressed transplant recipients. Interestingly, since mTOR inhibitors have both immunosuppressive and anti-cancer effects, they have the potential to simultaneously protect against immunologic graft loss and tumour development. Therefore, we designed a prospective RCT to determine if the mTOR inhibitor sirolimus can improve hepatocellular carcinoma (HCC)-free patient survival in liver transplant (LT) recipients with a pre-transplant diagnosis of HCC.Methods/DesignThe study is an open-labelled, randomised, RCT comparing sirolimus-containing versus mTOR-inhibitor-free immunosuppression in patients undergoing LT for HCC. Patients with a histologically confirmed HCC diagnosis are randomised into 2 groups within 4-6 weeks after LT; one arm is maintained on a centre-specific mTOR-inhibitor-free immunosuppressive protocol and the second arm is maintained on a centre-specific mTOR-inhibitor-free immunosuppressive protocol for the first 4-6 weeks, at which time sirolimus is initiated. A 21/2 -year recruitment phase is planned with a 5-year follow-up, testing HCC-free survival as the primary endpoint. Our hypothesis is that sirolimus use in the second arm of the study will improve HCC-free survival. The study is a non-commercial investigator-initiated trial (IIT) sponsored by the University Hospital Regensburg and is endorsed by the European Liver and Intestine Transplant Association; 13 countries within Europe, Canada and Australia are participating.DiscussionIf our hypothesis is correct that mTOR inhibition can reduce HCC tumour growth while simultaneously providing immunosuppression to protect the liver allograft from rejection, patients should experience less post-transplant problems with HCC recurrence, and therefore could expect a longer and better quality of life. A positive outcome will likely change the standard of posttransplant immunosuppressive care for LT patients with HCC.Trial RegisterTrial registered at http://www.clinicaltrials.gov: NCT00355862(EudraCT Number: 2005-005362-36)

Effects of the mTOR inhibitor sirolimus in patients with hepatocellular and cholangiocellular cancer

BackgroundHepatocellular cancer (HCC), as well as cholangiocellular cancer (CCC), has an extremely poor prognosis due to the extent of tumor at diagnosis and the underlying liver disease. Sirolimus is used in the transplantation setting as an immunosuppressive agent, but it also possesses antiproliferative and antiangiogenic properties. The objective of the study was to evaluate the effect of sirolimus on HCC and CCC.MethodsIn a prospective single-arm protocol, the tumor response to sirolimus as the primary endpoint was studied in 21 patients with advanced HCC and nine with CCC. Sirolimus was administered once daily by mouth, with the dose adjusted to a serum trough level between 4 and 15 μg/ml. Tumor response was evaluated by computed tomography (CT) or magnetic resonance imaging (MRI), according to the Response Evaluation Criteria in Solid Tumors (RECIST), every third month. Secondary measures were overall survival, time to tumor progression, tumor markers, and side effects.ResultsOf the patients with HCC, one had partial remission (PR) and fi ve patients had stable disease (SD) at 3 months. Of the patients with CCC, three had SD. The median survival for patients with HCC was 6.5 months (range, 0.2–36 months) and that for patients with CCC was 7 months (range, 2.6–35 months).ConclusionTreatment of HCC and CCC with sirolimus can induce temporary PD or SD. This pilot study indicates that sirolimus might be a promising drug for this treatment, but further clinical studies elucidating the biological effects are advocated.

Sirolimus Use in Liver Transplant Recipients With Hepatocellular Carcinoma: A Randomized, Multicenter, Open-Label Phase 3 Trial.

Background We investigated whether sirolimus-based immunosuppression improves outcomes in liver transplantation (LTx) candidates with hepatocellular carcinoma (HCC). Methods In a prospective-randomized open-label international trial, 525 LTx recipients with HCC initially receiving mammalian target of rapamycin inhibitor–free immunosuppression were randomized 4 to 6 weeks after transplantation into a group on mammalian target of rapamycin inhibitor–free immunosuppression (group A: 264 patients) or a group incorporating sirolimus (group B: 261). The primary endpoint was recurrence-free survival (RFS); intention-to-treat (ITT) analysis was conducted after 8 years. Overall survival (OS) was a secondary endpoint. Results Recurrence-free survival was 64.5% in group A and 70.2% in group B at study end, this difference was not significant (P = 0.28; hazard ratio [HR], 0.84; 95% confidence interval [95% CI], 0.62; 1.15). In a planned analysis of RFS rates at yearly intervals, group B showed better outcomes 3 years after transplantation (HR, 0.7; 95% CI, 0.48-1.00). Similarly, OS (P = 0.21; HR, 0.81; 95% CI, 0.58-1.13) was not statistically better in group B at study end, but yearly analyses showed improvement out to 5 years (HR, 0.7; 95% CI, 0.49-1.00). Interestingly, subgroup (Milan Criteria-based) analyses revealed that low-risk, rather than high-risk, patients benefited most from sirolimus; furthermore, younger recipients (age ⩽60) also benefited, as well sirolimus monotherapy patients. Serious adverse event numbers were alike in groups A (860) and B (874). Conclusions Sirolimus in LTx recipients with HCC does not improve long-term RFS beyond 5 years. However, a RFS and OS benefit is evident in the first 3 to 5 years, especially in low-risk patients. This trial provides the first high-level evidence base for selecting immunosuppression in LTx recipients with HCC.

mTOR inhibition with rapamycin causes impaired insulin signalling and glucose uptake in human subcutaneous and omental adipocytes

Rapamycin is an immunosuppressive agent used after organ transplantation, but its molecular effects on glucose metabolism needs further evaluation. We explored rapamycin effects on glucose uptake and insulin signalling proteins in adipocytes obtained via subcutaneous (n=62) and omental (n=10) fat biopsies in human donors. At therapeutic concentration (0.01 μM) rapamycin reduced basal and insulin-stimulated glucose uptake by 20-30%, after short-term (15 min) or long-term (20 h) culture of subcutaneous (n=23 and n=10) and omental adipocytes (n=6 and n=7). Rapamycin reduced PKB Ser473 and AS160 Thr642 phosphorylation, and IRS2 protein levels in subcutaneous adipocytes. Additionally, it reduced mTOR-raptor, mTOR-rictor and mTOR-Sin1 interactions, suggesting decreased mTORC1 and mTORC2 formation. Rapamycin also reduced IR Tyr1146 and IRS1 Ser307/Ser616/Ser636 phosphorylation, whereas no effects were observed on the insulin stimulated IRS1-Tyr and TSC2 Thr1462 phosphorylation. This is the first study to show that rapamycin reduces glucose uptake in human adipocytes through impaired insulin signalling and this may contribute to the development of insulin resistance associated with rapamycin therapy.

Post-nephrectomy development of renal function in living kidney donors: a cross-sectional retrospective study

BACKGROUND Increasing numbers of living donor kidney transplantations calls for better knowledge about long-term donor outcomes and risks. METHODS To explore long-term kidney donor outcomes and risks, we conducted a cross sectional retrospective study. To this end, we analysed renal function using measured glomerular filtration rate (mGFR) and estimated glomerular filtration rate (eGFR) as well as microalbuminuria, blood pressure (BP), body mass index, haemoglobin, albumin and parathyroid hormone in kidney donors nephrectomized between 1965 and 2005. RESULTS A total number of 573 kidney donors agreed to undergo medical follow-up examinations. The mean age (standard deviation) at donation was 47 (11) years and the mean time since donation was 14 (9) years. Both mean mGFR [68 (15) mL/min/1.73 m(2) body surface; P = 0.028] and mean eGFR [71 (16) mL/min/1.73 m(2) body surface; P < 0.001], based on modified diet renal dysfunction and iohexol or Cr-EDTA clearance, respectively, were found to decrease with age and to increase with time since donation. Special multivariable regression analyses reveal that for 30-year old donors, the median eGFR typically increases during the first 17 years, then remains constant for ~8 years and slowly declines thereafter. For 50-year-old donors, the median eGFR is expected to increase during the first 15 years or so and then to enter a phase of slight progressive decline. In total, 23% (126/546) of the donors were on antihypertensive medication. An additional 22% (117/543) of the donors were found to suffer from hitherto undiagnosed hypertension (BP >140/90 mm Hg). CONCLUSION Renal function of the remaining kidney in living donors is expected to improve for many years but will show signs of slight deterioration in the longer run.

The immunosuppressive agents rapamycin, cyclosporin A and tacrolimus increase lipolysis, inhibit lipid storage and alter expression of genes involved in lipid metabolism in human adipose tissue

Cyclosporin A (CsA), tacrolimus and rapamycin are immunosuppressive agents (IAs) associated with insulin resistance and dyslipidemia, although their molecular effects on lipid metabolism in adipose tissue are unknown. We explored IAs effects on lipolysis, lipid storage and expression of genes involved on lipid metabolism in isolated human adipocytes and/or adipose tissue obtained via subcutaneous and omental fat biopsies. CsA, tacrolimus and rapamycin increased isoproterenol-stimulated lipolysis and inhibited lipid storage by 20-35% and enhanced isoproterenol-stimulated hormone-sensitive lipase Ser552 phosphorylation. Rapamycin also increased basal lipolysis (~20%) and impaired insulins antilipolytic effect. Rapamycin, down-regulated the gene expression of perilipin, sterol regulatory element-binding protein 1 (SREBP1) and lipin 1, while tacrolimus down-regulated CD36 and aP2 gene expression. All three IAs increased IL-6 gene expression and secretion, but not expression and secretion of TNF-α or adiponectin. These findings suggest that CsA, tacrolimus and rapamycin enhance lipolysis, inhibit lipid storage and expression of lipogenic genes in adipose tissue, which may contribute to the development of dyslipidemia and insulin resistance associated with immunosuppressive therapy.

Liver transplantation for cholangiocarcinoma: Selection is essential for acceptable results

Abstract Background and aims. Cholangiocarcinoma (CCA) is considered a contraindication for liver transplantation by most liver transplant centers. The aim of this study has been to report our results as well as to explore factors that influence patient survival after liver transplantation for CCA. Patients. All transplant patients with CCA in Norway, Sweden and Finland during 1984–2005 were included (n = 53). Thirty-three patients (62%) had intrahepatic CCA. Twenty-one patients (40%) had a more advanced tumor (>TNM stage 2). Thirty-four of the 53 recipients (64%) had primary sclerosing cholangitis (PSC). Results. Patients with TNM stage ≤2 transplanted after 1995 had a 5-year survival rate of 48%. The overall 5-year patient survival rate was 25%. There was no difference in survival between patients with extrahepatic and intrahepatic CCA. The 5-year survival rate among patients with TNM stage ≤2 was 36%. Patients with TNM stage >2 had a 10% 5-year survival rate; the difference was significant at p < 0.01. Patients transplanted after 1995 had a significantly better 5-year survival rate than pre-1995 patients (38% vs. 0%, p < 0.01). Patients transplanted after 1995 with TNM ≤2 and CA 19-9 ≤100 had the 5-year survival of 58%. Conclusion. By selecting CCA patients with TNM stage ≤2 and a CA 19-9 ≤100 a reasonable 5-year survival rate is possible. We think that CCA in selected cases can be an acceptable indication for liver transplantation.

FKBP5 expression in human adipose tissue increases following dexamethasone exposure and is associated with insulin resistance

OBJECTIVE To study effects of dexamethasone on gene expression in human adipose tissue aiming to identify potential novel mechanisms for glucocorticoid-induced insulin resistance. MATERIALS/METHODS Subcutaneous and omental adipose tissue, obtained from non-diabetic donors (10 M/15 F; age: 28-60 years; BMI: 20.7-30.6 kg/m²), was incubated with or without dexamethasone (0.003-3 μmol/L) for 24 h. Gene expression was assessed by microarray and real time-PCR and protein expression by immunoblotting. RESULTS FKBP5 (FK506-binding protein 5) and CNR1 (cannabinoid receptor 1) were the most responsive genes to dexamethasone in both subcutaneous and omental adipose tissue (~7-fold). Dexamethasone increased FKBP5 gene and protein expression in a dose-dependent manner in both depots. The gene product, FKBP51 protein, was 10-fold higher in the omental than in the subcutaneous depot, whereas the mRNA levels were similar. Higher FKBP5 gene expression in omental adipose tissue was associated with reduced insulin effects on glucose uptake in both depots. Furthermore, FKBP5 gene expression in subcutaneous adipose tissue was positively correlated with serum insulin, HOMA-IR and subcutaneous adipocyte diameter and negatively with plasma HDL-cholesterol. FKBP5 SNPs were found to be associated with type 2 diabetes and diabetes-related phenotypes in large population-based samples. CONCLUSIONS Dexamethasone exposure promotes expression of FKBP5 in adipose tissue, a gene that may be implicated in glucocorticoid-induced insulin resistance.

Isolated hepatic perfusion for liver metastases of malignant melanoma.

The objective was to analyze the outcome of three treatment strategies using isolated hyperthermic liver perfusion (IHP) with melphalan for liver metastases of malignant melanoma. It was designed as an exploratory study. The setting was a single-center study in a university hospital. The study was carried out on 27 patients. IHP was used with modifications during three different time periods (IHP I, IHP II and IHP III), in technique and temperature (amount of melphalan: 0.5, 1.0 and 2 mg/kg body weight in the perfusate; 41, 40 and 40°C). Tumor response was estimated according to WHO criteria with computed tomography or MRI. Mortality and morbidity were secondary measures. Six of 11 patients in the IHP I cohort experienced a partial response (PR). In the IHP II cohort, two patients of 11 experienced a complete response and five a PR. In the IHP III cohort, five of five patients experienced a PR. Six postoperative deaths were reported (27%) (three in the IHP I and three in the IHP II series), secondary to liver insufficiency and multiorgan failure. Treatment of liver metastases of malignant melanoma with isolated hyperthermic melphalan perfusion has shown an impressive tumor response rate, which seems to be higher than the response rates reported for other systemic chemotherapy regimens. The maximum tolerated dose for melphalan in the perfusate was surpassed with a 2 mg/kg body weight. By modifying the technique and restricting the allowed tumor burden, the response rate remained high and the mortality was reduced.

Cyclosporine A and Tacrolimus Reduce the Amount of GLUT4 at the Cell Surface in Human Adipocytes: Increased Endocytosis as a Potential Mechanism for the Diabetogenic Effects of Immunosuppressive Agents

CONTEXT Immunosuppressive agents are associated with profound metabolic side effects including new-onset diabetes and dyslipidemia after organ transplantation. OBJECTIVE To investigate the effects of cyclosporine A (CsA) and tacrolimus on glucose uptake and insulin signaling in human adipocytes and their impact on the regulation of cellular trafficking of the glucose transporter 4 (GLUT4). DESIGN Isolated human adipocytes were incubated with therapeutic concentrations of either CsA or tacrolimus, and glucose uptake and expression of insulin signaling proteins were assessed. Furthermore, we studied effects of CsA and tacrolimus on the regulation of cellular trafficking of GLUT4 in differentiated human preadipocytes and L6 cells. RESULTS CsA and tacrolimus had a concentration-dependent inhibitory effect on basal and insulin-stimulated (14)C-glucose uptake in adipocytes. Although phosphorylation at Tyr1146 of the insulin receptor was inhibited by tacrolimus, the phosphorylation and/or protein levels of the insulin signaling proteins IRS1/2, p85-PI3K, PKB, AS160, and mTORC1, as well as GLUT4 and GLUT1, were unchanged by CsA or tacrolimus. Furthermore, CsA and tacrolimus reduced the GLUT4 amount localized at the cell surface of differentiated human preadipocytes and L6 cells in the presence of insulin. This occurred by an increased rate of GLUT4 endocytosis, with no change in the exocytosis rate. CONCLUSIONS These results suggest that therapeutic concentrations of CsA and tacrolimus can inhibit glucose uptake independent of insulin signaling by removing GLUT4 from the cell surface via an increased rate of endocytosis. This mechanism can contribute to the development of insulin resistance and diabetes associated with immunosuppressive therapy. In addition, it may provide novel pharmacological approaches for the treatment of diabetes.