Interferon gamma inhibits both proliferation and expression of differentiation-specific alpha-smooth muscle actin in arterial smooth muscle cells.

Differentiation of muscle cells is characterized morphologically by the acquisition of contractile filaments and characteristic shape changes, and on the molecular level by induction of the expression of several genes, including those for the muscle-specific alpha-actin isoforms. IFN-gamma is an inhibitor of proliferation for several cells, including vascular smooth muscle, and is also an inducer of differentiated properties for several hematopoietic cells. We have therefore investigated whether IFN-gamma affects the expression of alpha-smooth muscle actin in cultured arterial smooth muscle cells. Cells exposed to IFN-gamma show a reduction of alpha-smooth muscle actin-containing stress fibers, as detected by immunofluorescence. The effect was observed in all phases of the cell cycle, and was caused by a reduction of the synthesis of alpha-smooth muscle actin protein as revealed by two-dimensional electrophoretic analysis of actin isoforms. RNA hybridization using a cRNA probe that hybridizes to all actin mRNAs showed that IFN-gamma-treated cells have a reduced content of the 1.7-kb mRNA that codes for alpha-smooth muscle actin, and to a lesser extent, also of the 2.1-kb mRNA encoding the beta and gamma-cytoplasmic actins. The reduction of alpha-smooth muscle actin mRNA was confirmed using an alpha-smooth muscle actin-specific cRNA probe. The reduction of alpha-smooth muscle actin mRNA occurs within 12 h, and is dependent on protein synthesis, since cycloheximide treatment reversed the effect. The inhibition of this mRNA species was dose dependent, and detectable by RNA hybridization at a dose of 50 U/ml IFN-gamma. These results suggest that the differentiation of arterial smooth muscle cells is not necessarily coupled to an inhibition of cellular proliferation. Instead, IFN-gamma may regulate the expression of several genes that control both proliferation and expression of differentiation markers.

Autologous bone marrow transplantation for recurrent malignant lymphoma after liver transplantation.

BACKGROUND: Cancer chemotherapy in chronic carriers of hepatitis B virus is known to promote viral replication, and, when immunosuppressive treatment is stopped, the return of immune competence can be followed by a fulminant hepatitis. Liver transplantation may be required and has been successfully performed for this condition. However, malignancy recurrence after transplantation has not been reported yet. METHODS AND RESULTS: We here report the case of an asymptomatic hepatitis B surface antigen carrier who developed a malignant lymphoma, which was treated by chemotherapy. After cessation of chemotherapy, he developed a fulminant hepatitis, requiring liver transplantation. Three years later, he developed a recurrent malignant lymphoma, which was treated successfully by autologous bone marrow transplantation. In order to prevent viral replication, lamivudine and intermittent administration of fresh-frozen plasma highly concentrated in anti-HBs immunoglobulin was initiated before the bone marrow transplantation. The patient remains well 12 and 56 months after autologous bone marrow and liver transplantation, respectively. CONCLUSIONS: This experience suggests that all hepatitis B surface antigen-positive patients for whom chemotherapy is indicated would benefit from prophylactic antiviral hepatitis B virus therapy. Furthermore, successful autologous bone marrow transplantation is possible after liver transplantation.

Magnetic resonance imaging with superparamagnetic iron oxide particles to evaluate hepatic macrophage-monocytic phagocytosis after arterial devascularization in minipigs.

RATIONALE AND OBJECTIVES: We examined the effects of arterial ischemia on the phagocytic activity of the hepatic macrophage-monocytic phagocytic system (MMPS). METHODS: Six minipigs were studied before and 24 hr after complete arterial devascularization of the liver. Magnetic resonance (MR) imaging was performed at 1.5 T using superparamagnetic iron oxide (SPIO) particles (18 mumol Fe/kg body weight) as an MMPS-specific contrast agent. Hepatobiliary scintigraphy, measurements of serum liver enzymes, and histology also were obtained. RESULTS: On MR imaging, the postcontrast-to-precontrast ratios of the arterially devascularized livers were significantly higher than the corresponding baseline values (p < .01). The greatest difference (52%) between the baseline and the postoperative values was observed on gradient-echo (GE) images. Scintigraphy, laboratory analyses, and histology results indicate that the MR imaging findings were probably predominantly attributable to a reduction in phagocytic activity of the hepatic MMPS. CONCLUSION: SPIO particles have already proved useful for improving detection of liver neoplasms on MR imaging, but they also may provide a novel way of evaluating the function of the hepatic MMPS in liver diseases.

The cytoskeleton of arterial smooth muscle cells during development, atheromatosis, and tissue culture.

Arterial smooth muscle cells (SMCs) assume cytoskeletal features of embryonic cells during human and experimental atheromatosis, as well as when placed in culture. The expression of alpha-smooth muscle (SM) actin can be used to monitor these changes. The synthesis of alpha-SM actin is decreased early after plating in cultured cells and early after endothelial lesion in animals. The amount of mRNA for alpha-SM actin is not affected in cultured cells, although it is drastically decreased in the carotid artery after endothelial injury. Heparin does not modify in vivo the early decrease of alpha-SM actin mRNA and synthesis, but, by inhibiting the entry of SMC into the S phase of the cell cycle, it produces an early reinduction of alpha-SM actin.

[Risk in major hepatectomy. A consecutive series of 113 extensive hepatectomies]. / Le risque des hépatectomies majeures. Une série consécutive de 113 hépatectomies larges.

Up to now, liver resections have been the initial treatment of almost all cancers and benign tumors limited to a liver lobe. This retrospective review assesses the results of a consecutive series of 113 major elective hepatic resections during a ten-year period. Major hepatectomy was defined by the resection of at least 3 Couinaud segments. Mean age was 52 years (20 to 79 years). There were 62 women and 51 men. 35 resections were performed for colorectal metastases, 22 for a benign tumor, 20 for non-colorectal metastases, 11 for hydatid disease, 10 for hepatocarcinoma, 7 for cholangiocarcinoma and 8 for other indications. The resections performed were 86 right hepatectomies with 18 extended right hepatectomies, 24 left hepatectomies with 4 extended left hepatectomies and 3 trisegmentectomies. Total vascular exclusion was used in 22 patients (19%). Mortality rate was zero. Significant morbidity was encountered in 24 patients (21%). These results suggest that the mortality rate may be independent of the extent of liver resection, provided that hepatic function is normal and preoperative selection adequate. With improving surgical management and techniques, and the use of intra-operative sonography, extensive liver surgery can now be performed with a very low mortality rate.

[Clonogenic growth of tumor cells in vitro]. / Etudes sur la croissance clonogène des cellules tumorales in vitro.

We expose here our first results concerning clonogenic growth of 40 cases of malignant tumor plated in semi-solid medium (methylcellulose). The growth is determined by the presence at day 21 of colonies (cellular group with more than 60 micron diameter). 26 cases were considered significant. A 61% growth has been observed with primary solid tumors, and 83.4% with ascites, ovarian carcinoma growing the best. Cellular viability, plating efficiency and when the cellular number allowed it, linear graphic curves have been established. An ultrastructural morphological study, illustrated here by 2 cases--one ovarian carcinoma and one colonic adenocarcinoma cell line--has shown that all colony 's cells belong to a same cellular type and present various degrees of differentiation, suggesting a possible analogy between our observations and the hypothetical tumor cell model, concerning human carcinoma's organisation and self renewal.

[Follow-up and results of liver transplantation for primary biliary cirrhosis]. / Suivi et rresultats de la transplantation hépatique pour cirrhose biliaire primitive.

Primary biliary cirrhosis is regarded as one of the optimal indications for orthotopic liver transplantation in adults. With the decrease in the operative mortality, the analysis of the potential long-term complications including disease recurrence is becoming increasingly relevant. The purpose of this study was to evaluate the long-term results of liver transplantation for primary biliary cirrhosis in our center. From 1988, 14 patients were transplanted for this indication and all of them were alive with a mean follow-up of 43 months by the end of June 1995. At that time, all complications related to chronic liver disease were reversed by the transplant except for osteopenia. Lumbar column fractures and overweight were the major inconveniences encountered. Hypertension and diabetes related to antirejection therapy disappeared during the first year of follow-up in all but one patient. Recurrence of the disease was not encountered in this series where a triple association of immunosuppressive therapy was maintained in each patient. At long-term, the frequency of disease recurrence in the liver allograft seems quite low and even in this situation immunosuppressive agents may alter the evolution of the disease. All patients (n - 12) who had at least 1 year of follow-up had a normal level of bilirubin and their quality of life was good to excellent. These results, confirmed by the international experience, support the notion that patients suffering from primary biliary cirrhosis should be transplanted as early as complications from this chronic liver disease occur.

Interphase cytogenetic analysis reveals numerical chromosome aberrations in large liver cell dysplasia.

BACKGROUND/AIMS: Little is known about genetic alterations in large or small liver cell dysplasia. The aim of this study was to determine whether these lesions present numerical chromosome aberrations. METHODS: Eight patients with hepatocellular carcinoma on cirrhosis, five with large liver cell dysplasia and three with small liver cell dysplasia, were analysed by in situ hybridization with different centromeric nucleic acid probes specific respectively for chromosomes 1, 7, 17 and 18. In each case results were compared between dysplastic, tumoral and non-dysplastic cirrhotic cells. Four normal livers were also studied with the same method and served as cytogenetic controls. RESULTS: All cases of large liver cell dysplasia dysplayed a polysomic population for each investigated chromosome. A high variability of numerical chromosome aberrations was observed with a copy number of chromosomes which ranged from two to more than six. By contrast, only one case of small liver cell dysplasia showed chromosomal anomalies. Numerical aberrations of at least one chromosome were observed in six of the eight hepatocellular carcinoma while the non-dysplastic cirrhosis and normal liver always showed a diploid pattern. CONCLUSIONS: These results demonstrate that cellular modifications in large liver cell dysplasia coexist with an early acquisition of genomic alterations, supporting the view that these phenotypic changes are preneoplastic.

[Results of surgical treatment of hepatic metastasis of colorectal origin]. / Résultats du traitement chirurgical des métastases hépatiques d'origine colorectale.

Surgery is the only treatment which can achieve long-term survival of patients with colorectal liver secondaries. This study reports the results in 71 patients with liver metastases who underwent hepatic resection from January 1980 to December 1994. The mean age was 60 years (range 37 and 80 years). Operations included 33 right hepatectomies, 5 extended right hepatectomies, 6 left hepatectomies, 11 left lobectomies,. Surgery was macroscopically and microscopically curative in 61 patients. Information was not available in 2 patients. Significant morbidity was observed in 37% of patients. Actuarial survival at 1, 3 and 5 years was 83%, 27% and 20% respectively. At the end of the follow-up, 50 patients had died and 6 were lost to follow-up. Techniques of hepatic resection for secondaries are well established and postoperative mortality is low. Pending advances in chemotherapy, we recommend surgery as being the only way of improving long-term survival in patients with colorectal hepatic metastases.

Alpha-smooth muscle actin is transiently expressed in embryonic rat cardiac and skeletal muscles.

Actin isoform expression may change during development, and in certain physiological, experimental and pathological situations. It is accepted that during sarcomeric (skeletal and cardiac) muscle development, the alpha-skeletal and alpha-cardiac isoforms of actin accumulate rapidly at the onset of muscle fibre formation, while there is a rapid fall in the expression of nonmuscle (beta and gamma) actin isoforms. Here we show that, before birth, both skeletal and myocardial cells express significant amounts of alpha-smooth muscle actin mRNA and protein. This expression is transient and disappears over the 1-7 days following birth. Our findings show that the program regulating actin isoform expression in sarcomeric muscle development is complex and that alpha-smooth muscle actin participates in this process.

Expression of vascular endothelial growth factor in digestive neuroendocrine tumours.

AIMS: Angiogenesis is a complex multistep process essential for tumour growth. Vascular endothelial growth factor (VEGF) is a potent endothelial cell mitogen and vascular permeability-inducing agent. Recent studies have shown that VEGF expression is correlated to microvessel density and tumour progression. The aim of this study was to analyse VEGF expression in a series of gastrointestinal neuroendocrine tumours. METHODS AND RESULTS: Surgical specimens from 28 gastrointestinal carcinoids and 20 pancreatic endocrine tumours were examined for VEGF expression by immunohistochemistry. Intense cytoplasmic staining for VEGF was observed in several cells of the islets of Langerhans and in neuroendocrine cells of normal digestive mucosa. All midgut carcinoids showed strong VEGF expression in tumoral cells. Positive VEGF immunostaining was observed in 16 of 20 neuroendocrine pancreatic tumours but it was usually much lower than in midgut carcinoids. Western blotting analysis in eight cases identified a major band at 30-32 kDa. No correlation between VEGF expression and tumour stage was found. CONCLUSIONS: This study demonstrates that neuroendocrine cells are a major source of VEGF, particularly in midgut carcinoids. This finding suggests that the presence of VEGF may be required to maintain the differentiated state of capillary vessels in these hypervascular tumours. Such secretion, in conjunction with the other growth factors synthesized by these neuroendocrine tumours, may have an important role in tumour growth.

[Start of an adult living donor liver transplantation program in Switzerland]. / Début d'un programme adulte de donneurs vivants de foie en Suisse.

The shortage of cadaver organs has prompted transplant centres to seek new sources of grafts. While living-donor left lobe transplantation (segments II and III) is an established procedure for children, living donor right liver transplantation (segments V, VI, VII, VIII), which can provide adequate liver mass for an average-sized adult patient, is technically more demanding and potentially associated with higher risks for the donor. In view of the permanent shortage of organs in Switzerland, we started an adult living donor liver transplantation programme in 1999 with the approval of the Clinical Ethics Committee of Geneva University Hospitals. Donor evaluation was performed only after the recipient had been officially registered for transplantation in the national waiting list. Preoperative evaluation consisted of a preliminary information phase with blood tests and Doppler ultrasonography, a second phase with radiological non invasive investigations (CT scan with volume measurements, magnetic resonance cholangiography) and a third phase including liver biopsy and angiography. A formal psychiatric evaluation was performed in all cases and detailed consent was required. Eight potential donors were investigated, 5 were not retained because of too small right liver or steatosis, and 3 were accepted (wife, son, sister). Living-donor hepatectomy was performed without interrupting the vascular blood flow. The liver graft was perfused ex-situ with University of Wisconsin solution. The grafts were anastomosed to the preserved vena cava of the recipient and the portal and arterial anastomoses were performed without interposition grafts, with short cold ischaemic times in the 3 cases. The graft-to-recipient weight ratio ranged from 1.04 to 1.12%. The grafts worked immediately; the post-operative course in the 3 recipients was unremarkable and no rejection episode occurred. Significant complications were observed in one donor (percutaneously drained bilioma and spontaneously resolved popliteal sensory palsy). Living-donor right liver transplantation is a potentially valuable solution to the increasing shortage of donor organs. The procedure can be performed safely provided stringent criteria for donor selection, for donor-recipient coupling (> 1% graft to body weight ratio) and for centre selection (experience in liver surgery, reduced and split liver transplantation) are applied.

Auxiliary liver transplantation: regeneration of the native liver and outcome in 30 patients with fulminant hepatic failure--a multicenter European study.

Auxiliary liver transplantation (LT) is a special procedure of LT which could be proposed to patients with fulminant hepatic failure (FHF) and has for aim that complete regeneration of the native liver (NL) left in place will allow the graft recipient to resume normal liver function after allograft withdrawal. We report 30 cases of auxiliary LT performed for FHF in 12 European centers. Twenty-five of 30 patients were younger than 50 years. The cause of FHF was hepatitis A virus (HAV) in 4 patients, hepatitis B virus (HBV) in 7, paracetamol overdose in 5, ecstasy in 2, hepatotoxic drugs in 4, autoimmune hepatitis in 2, liver lesions of preeclampsia in 1 and unknown in 5. A postoperative, both clinical and histological follow-up of more than 3 weeks was obtained in 22 patients, enabling us to look for indicators predictive of NL regeneration and outcome. Histological changes observed in the NL included complete regeneration in 68%, incomplete regeneration with obvious fibrous sequelae in 14% and severe liver fibrosis or cirrhosis in 18%, of the 22 patients studied. The percentage and distribution of necrosis observed in tissue samples of the NL at the time of transplantation was not related to the final outcome. Complete NL regeneration was observed in 15 patients, out of whom 14 were younger than 40 years. Patients with complete regeneration were mainly affected by FHF due to HAV, HBV, or paracetamol overdose. After a follow-up of 18/11 (mean/median) months (range, 3 to 67 months), 19 of the 30 patients (63%) survived and 13 of them (68%), i.e., 43% of the 30 patients, had resumed normal NL function, with interrupted immunosuppression, the ultimate goal of emergency auxiliary LT. We conclude that, in patients with FHF, auxiliary LT is a procedure feasible in a number of centers and is associated with a complete regeneration capability of the NL in a majority of survivors, especially in those younger than 40 years. Confirmation of these encouraging preliminary results by large-scale prospective studies is required.