Microsatellite instability mutator phenotype in hepatocellular carcinoma in non-alcoholic and non-virally infected normal livers

Microsatellite instability (MSI) seems to be a rare event in hepatocarcinogenesis and might actually be associated with the progression of hepatocellular carcinoma (HCC) in which the liver is often the site of chronic hepatitis or cirrhosis. The aim of this work was to define the MSI phenotype in HCC affecting exclusively normal livers to avoid slippage errors due to cirrhosis. One hundred and sixty-four patients with HCC affecting non-cirrhotic livers were operated on in our hospital between 1984 and 2001. We analyzed 37 patients selected for low alcohol consumption and the absence of HBV or HCV infection. All the livers were histologically normal. MSI was analyzed according to the criteria defined during the conference consensus workshop for colorectal cancer. High MSI (MSI-H > 30%) was found in 6 (16%) and low MSI (MSI-L < 30%) in 10 (27%) of the 37 HCCs. None of the 10 microsatellite markers tested were altered in the remaining 21 tumors (57%). Immunohistochemistry showed that normal amounts of hMLH1 and hMSH2 were present both in MSI-H and in MSI-L HCCs. MSI-H was significantly associated with more aggressive histological tumor features and a shorter median delay before recurrence. Thus, we have found a small subgroup of HCC tumors which can be considered as a new clinical/histological entity.     

A novel E1A-E1B mutant adenovirus induces glioma regression in vivo

Malignant gliomas are the most frequently occurring primary brain tumors and are resistant to conventional therapy. Conditionally replicating adenoviruses are a novel strategy in glioma treatment. Clinical trials using E1B mutant adenoviruses have been reported recently and E1A mutant replication-competent adenoviruses are in advanced preclinical testing. Here we constructed a novel replication-selective adenovirus (CB1) incorporating a double deletion of a 24 bp Rb-binding region in the E1a gene, and a 903 bp deleted region in the E1b gene that abrogates the expression of a p53-binding E1B-55 kDa protein. CB1 exerted a potent anticancer effect in vitro in U-251 MG, U-373 MG, and D-54 MG human glioma cell lines, as assessed by qualitative and quantitative viability assays. Replication analyses demonstrated that CB1 replicates in vitro in human glioma cells. Importantly, CB1 acquired a highly attenuated replicative phenotype in both serum-starved and proliferating normal human astrocytes. In vivo experiments using intracranially implanted D-54 MG glioma xenografts in nude mice showed that a single dose of CB1 (1.5 x 10(8) PFU/tumor) significantly improved survival. Immunohistochemical analyses of expressed adenoviral proteins confirmed adenoviral replication within the tumors. The CB1 oncolytic adenovirus induces a potent antiglioma effect and could ultimately demonstrate clinical relevance and therapeutic utility.     

Cells as vehicles for cancer gene therapy: the missing link between targeted vectors and systemic delivery?

Systemic administration of currently manufactured viral stocks has not so far achieved sufficient circulating titers to allow therapeutic targeting of metastatic disease. This is due to low initial viral titers, immune inactivation, nonspecific adhesion, and loss of particles. One way to exploit the elegant molecular manipulations that have been made to increase vector targeting is to protect these vectors until they reach the local sites of tumor growth. Various cell types home preferentially to tumors and can be loaded with the constructs required to produce targeted vectors. Here we discuss the potential of using such cell carriers to chaperone precious vectors directly to the tumors. The vectors can incorporate mechanisms to achieve tumor site-inducible expression, along with tumor cell-specific expression of the therapeutic gene and/or replicating viral genomes that would be released at the tumor. In this way, the great advances that have so far been made with the engineering of vector tropisms might be genuinely exploited and converted into clinical benefit.     

Real-time quantification of AFP mRNA to assess hematogenous dissemination after transarterial chemoembolization of hepatocellular carcinoma

OBJECTIVE: To determine whether the number of hepatocytes containing AFP mRNA shed into the bloodstream during transarterial chemoembolization (TAE) affects the incidence and pattern of recurrence of hepatocellular carcinoma (HCC). PATIENTS AND METHODS: We developed a Taqman procedure to quantify AFP mRNA prospectively in 52 consecutive patients before and after TAE. Results are expressed in hepatocytes /mL. RESULTS: Thirteen of the patients (24.5%) were positive for AFP mRNA (42 +/- 19 hepatocytes/mL) before TAE and 13 (24.5%) (80 +/- 32 hepatocytes/mL) after TAE; the difference was not significant. The presence of AFP mRNA in the bloodstream before TAE was associated with larger nodules (85.2 +/- 73.8 mm versus 34.8 +/- 26.1 mm; P = 0.006). Six of the patients were excluded from the analysis because they underwent curative surgery or were lost to follow-up. The circulating levels of AFP mRNA released in the 46 remaining patients after TAE did not affect metastasis-free survival. A significant number of extrahepatic metastases were found in patients exhibiting at least 1 AFP mRNA-positive blood sample either before or after TAE. However, the TAE procedure did not increase the risk of extrahepatic recurrences. CONCLUSION: Cells containing AFP mRNA are inconsistently released into the circulation during TAE. The amount of these cells released does not affect the recurrence of HCC.     

Recombinant E. coli efficiently delivers antigen and maturation signals to human dendritic cells: presentation of MART1 to CD8+ T cells

The generation of tumour-specific cytotoxic T-lymphocyte (CTL) responses is the primary focus in the design of immunotherapeutic cancer vaccines. We have recently demonstrated generation of ovalbumin (OVA)-specific CTLs and tumour-protection in a murine tumour model using vaccination with dendritic cells (DCs) pulsed with E. coli expressing listeriolysin O (LLO) and OVA as a model antigen. In this system paraformaldehyde fixation of E. coli/LLO provided an additional safety feature without compromising vaccine efficacy. We therefore reasoned that paraformaldehyde-fixed recombinant E. coli expressing LLO would be an efficient vehicle for the delivery of human tumour antigens to human DCs. In the present study, we demonstrate that fixed E. coli expressing LLO are taken up efficiently by human monocyte-derived DCs (MoDCs) with minimal toxicity. As a consequence of the interaction with bacteria, human DCs undergo marked phenotypic and functional maturation. Furthermore, we show that fixed E. coli/LLO expressing the well-characterised human melanoma antigen, MART1, efficiently deliver the HLA-A2-restricted MART1(27-35) epitope for processing and presentation on human MoDCs, suggesting the potential of this system as a novel strategy for human tumour immunotherapy.     

Abnormal placentation and selective embolization of the uterine arteries

OBJECTIVE: Abnormal placentation accounts for more than 50% of uterine artery embolization failure. The authors report their experience in this situation. STUDY DESIGN: Seven women presented with abnormal placentation. Uterine artery embolization was carried out in emergency or prophylactic control of postpartum bleeding. RESULTS: In five patients, control of postpartum hemorrhage was obtained without hysterectomy. In two cases with no placental removal and prophylactic procedures, hysterectomy and blood transfusion were not necessary. The manual removal of the placenta was achieved secondarily, respectively on the 25th and the 12th day. CONCLUSIONS: The success rate of uterine artery embolization for postpartum bleeding appears to be lower with abnormal placentation. In none of the cases with the placenta present was it possible to leave the residual placenta in place. However, embolization may permit a safe waiting period and spontaneous migration of the placenta. When the diagnosis is made before delivery, prophylactic uterine artery embolization without placental removal should be considered to reduce blood transfusion and preserve fertility.     

Results of recto-vaginal fistula repair: retrospective analysis of 48 cases

OBJECTIVE: To evaluate the long-term outcome of the Musset technique of recto-vaginal fistula (RVF) repair. STUDY DESIGN: During the years 1992-1998, 48 women underwent recto-vaginal fistula repair. A retrospective study in a university tertiary referral center was conducted. RESULTS: The main etiologies were obstetrical trauma (25), local infection (11), inflammatory disease (7), and post surgery (3). Thirty women (63%) had a previous fistula repair failure. The mean+/-S.D. fistula diameter was 1.4+/-1.0, and in 40% of the patients the fistula diameter was >2.5cm. In 19 cases (39.6%) there was a complete opening of the perineum and anal sphincter. Gas and stool incontinence before the operation were noted in 85 and 75% of the patients, respectively. Successful anatomic results were achieved in all patients. Five patients were re-operated due to gas and stool incontinence, and all but one had satisfactory anatomic and functional satisfactory results. The success rates in women with Crohn's disease and with a previous RVF repair failure were 100 and 98%, respectively. No major intra or postoperative complications were noted. CONCLUSION: The Musset procedure provide excellent anatomic and functional results and women with Crohn's disease or previous RVF repair have comparable long-term results.     

Proteomic analysis reveals that 14-3-3sigma is down-regulated in human breast cancer cells

The class of molecular chaperones known as 14-3-3 is involved in the control of cellular growth by virtue of its apparent regulation of various signaling pathways, including the Raf/mitogen-activated protein kinase pathway. In breast cancer cells, the sigma form of 14-3-3 has been shown to interact with cyclin-dependent kinases and to control the rate of entry into mitosis. To test for a direct role for 14-3-3 in breast epithelial cell neoplasia, we have quantitated 14-3-3 protein levels using a proteomic approach based on two-dimensional electrophoresis and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF). We show here that 14-3-3sigma protein is strongly down-regulated in the prototypic breast cancer cell lines MCF-7 and MDA-MB-231 and in primary breast carcinomas as compared with normal breast epithelial cells. In contrast, levels of the alpha, beta, delta, or zeta isoforms of 14-3-3 were the same in both normal and transformed cells. The data support the idea that 14-3-3sigma is involved in the neoplastic transition of breast epithelial cells by virtue of its role as a tumor suppressor; as such, it may constitute a robust marker with clinical efficacy for this pathology.