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Dominique Franco

Publications and source records attributed to Dominique Franco.

At least 19 recordsLinked to original sources
PubMed2007

Transcriptome classification of HCC is related to gene alterations and to new therapeutic targets.

UNLABELLED: Hepatocellular carcinomas (HCCs) are a heterogeneous group of tumors that differ in risk factors and genetic alterations. We further investigated transcriptome-genotype-phenotype correlations in HCC. Global transcriptome analyses were performed on 57 HCCs and 3 hepatocellular adenomas and validated by quantitative RT-PCR using 63 additional HCCs. We determined loss of heterozygosity, gene mutations, promoter methylation of CDH1 and CDKN2A, and HBV DNA copy number for each tumor. Unsupervised transcriptome analysis identified 6 robust subgroups of HCC (G1-G6) associated with clinical and genetic characteristics. G1 tumors were associated with low copy number of HBV and overexpression of genes expressed in fetal liver and controlled by parental imprinting. G2 included HCCs infected with a high copy number of HBV and mutations in PIK3CA and TP53. In these first groups, we detected specific activation of the AKT pathway. G3 tumors were typified by mutation of TP53 and overexpression of genes controlling the cell cycle. G4 was a heterogeneous subgroup of tumors including TCF1-mutated hepatocellular adenomas and carcinomas. G5 and G6 were strongly related to beta-catenin mutations that lead to Wnt pathway activation; in particular, G6 tumors were characterized by satellite nodules, higher activation of the Wnt pathway, and E-cadherin underexpression. CONCLUSION: These results have furthered our understanding of the genetic diversity of human HCC and have provided specific identifiers for classifying tumors. In addition, our classification has potential therapeutic implications because 50% of the tumors were related to WNT or AKT pathway activation, which potentially could be targeted by specific inhibiting therapies.

Adenoma↗
PubMed2006

Efficient hepatocyte engraftment in a nonhuman primate model after partial portal vein embolization.

BACKGROUND: Hepatocyte transplantation could be an alternative to whole liver transplantation for the treatment of metabolic liver diseases. However, the results of clinical investigations suggest that the number of engrafted hepatocytes was insufficient to correct metabolic disorders. This may partly result from a lack of proliferation of transplanted hepatocytes. In rodents, portal ligation enhances hepatocyte engraftment after transplantation. We investigated the effects of partial portal ligation and embolization on engraftment and proliferation of transplanted hepatocytes in primates. METHODS: Hepatocyte autotransplantation was performed in Macaca monkeys. The left lateral lobe was resected for hepatocyte isolation. The first group of monkeys underwent surgical ligation of the left and right anterior portal branches; in the second group, the same portal territories were obstructed by embolization with biological glue. To evaluate the proportion of cell engraftment hepatocytes were Hoechst-labeled and transplanted via the portal vein. Cell proliferation was measured by BrdU incorporation. RESULTS: Hepatocyte proliferation was induced by both procedures but it was significantly higher after partial portal embolization (23.5% and 11.2% of dividing hepatocytes on days 3 and 7) than after ligation (3% and 0.8%). Hepatocytes engrafted more efficiently after embolization than after ligation. They proliferated and participated to liver regeneration representing 10% of the liver mass on day seven and their number remained constant on day 15. CONCLUSIONS: These data suggest that partial portal embolization of the recipient liver improves engraftment of transplanted hepatocytes in a primate preclinical model providing a new strategy for hepatocyte transplantation.

Animals↗
PubMed2006

Efficient ex vivo gene transfer into non-human primate hepatocytes using HIV-1 derived lentiviral vectors.

BACKGROUND/AIMS: Lentivirus-mediated ex vivo gene therapy is becoming a promising approach for the treatment of liver metabolic disorders. However, the feasibility of this approach needs to be studied in large animal models. The purpose of this study was to evaluate the efficacy of ex vivo gene transfer into Macaca hepatocytes with two different HIV-1 derived lentiviral vectors. METHODS: A self-inactivating lentivector was constructed to express GFP under the control of the hepatic apolipoprotein A-II promoter. Freshly isolated and thawed hepatocytes were transduced in suspension with lentiviral vectors expressing the GFP gene under the control of a ubiquitous promoter (EF1-alpha) and the apolipoprotein A-II promoter. Transduced thawed hepatocytes were transplanted into the spleen of newborn mice, and livers analyzed 4 and 12 weeks after transplantation. RESULTS: We show that lentivectors are efficient in transducing hepatocytes in suspension either freshly isolated or cryopreserved. We also show that thawed and transduced hepatocytes engrafted and participated in liver growth after transplantation into newborn mice and that the apolipoprotein A-II promoter is functional. CONCLUSIONS: Our data show that transplantation of transduced hepatocytes into monkeys should allow to evaluate the fate of transplanted cells and transgene expression in a pre-clinical model of ex vivo gene therapy.

Actins↗
PubMed2006

[An exceptional and misleading case of choledochal cyst].

The authors report a case of choledocal cyst extended to left and right hepatic ducts. An heterogeneous intracystic fluid, partial calcification of cystic wall, a slight positivity of echinoccosis serology in a patient from a highly endemic country erroneously led to diagnosis of hydatid cyst invading the left hepatic duct. The diagnosis of choledocal cyst was done on the resection specimen after left hepatectomy. A small patch of cyst wall with terminations of both right sectorial hepatic ducts was used for cysto-jejunal Roux-en-Y loop anastomosis. Peculiarities of this type of choledocal cyst are discussed.

Adult↗
PubMed2005

Retroviral display of urokinase-binding domain fused to amphotropic envelope protein.

Tumors frequently express urokinase (uPA) receptor (uPAR). To investigate whether uPAR can efficiently target cancerous cells using amphotropic retroviral vectors, we generated a retrovirus displaying the amino-terminal fragment (ATF) of uPA as an N-terminal extension of viral envelope protein. We also made use of a "two-step strategy" by inserting a uPA cleavage site between the ATF moiety and the envelope. We measured the ability of ATF-bearing chimeric envelopes to infect huPAR-overexpressing Madin-Darby canine kidney (MDCK) and control MDCK II cells. The ATF-viruses infected both MDCK cell lines with an equivalent efficiency, suggesting that the chimeric viruses were not sequestered by uPAR and infect cells preferentially via the Pit-2 receptor. The addition of a uPA cleavage site increased the infection level of huPAR-MDCK cells by 2-fold when uPA was present in the infection medium. Surprisingly, ATF-env viruses infected huPAR-MDCK cells 5.5-fold more efficiently in the presence of exogenous uPA. This stimulatory effect of uPA on infection of huPAR-MDCK cells by the ATF-env virus was completely abolished by methyl-beta-cyclodextrin, suggesting that this effect involves the caveolar endocytosis pathway.

Animals↗
PubMed2005

Follistatin allows efficient retroviral-mediated gene transfer into rat liver.

Retroviral vectors are widely used tools for gene therapy. However, in vivo gene transfer is only effective in dividing cells, which, in liver, requires a regenerative stimulus. Follistatin is effective in promoting liver regeneration after 90% and 70% hepatectomy in rats. We studied its efficacy on liver regeneration and retroviral-mediated gene delivery in 50% hepatectomized rats. When human recombinant follistatin was infused into the portal vein immediately after 50% hepatectomy, hepatocyte proliferation was significantly higher than in control 50% hepatectomized rats. A single injection of virus particles administered 23 h after follistatin infusion resulted in more than 20% gene transduction efficiency in hepatocytes compared to 3% in control rats. It is concluded that a single injection of follistatin induces onset of proliferation in 50% hepatectomized rats and allows efficient retroviral-mediated gene transfer to the liver.

Animals↗
PubMed2005

Laparoscopic hepatic resection for hepatocellular carcinoma. Retrospective study of 12 patients.

AIMS: To assess the results of laparoscopic liver resection for hepatocellular carcinoma. PATIENTS AND METHODS: From 1998 to 2003, 12 laparoscopic liver resections for hepatocellular carcinoma were performed. RESULTS: There were no operative complications and no deaths. Conversion to laparotomy was required in one patient (8%) and transfusion in three patients (25%). One patient died of liver failure. Postoperative complications occurred in three patients (25%): trocar site bleeding, cardiac failure and biliary collection. The mean hospital stay was 5 days. No ascites and no transient liver failure occurred. During the mean follow up of 15 months the recurrence rate was 45.5%. No port site or peritoneal metastases were observed. Treatment of recurrence was second resection in two patients and microwave coagulation therapy in two other patients. Mean survival was 24 months. CONCLUSION: Laparoscopic liver resection is feasible in hepatocellular carcinoma if the tumor is unique, smaller than 5 centimeters and located in the left lateral segments or in the anterior or inferior segments of the right liver. Postoperative morbidity is low and long-term results seem to be similar to laparotomy.

Adult↗
PubMed2004

Impact of cytomorphological detection of circulating tumor cells in patients with liver cancer.

The clinical impact of circulating tumor cell (CTC) detection is controversial, mainly due to drawbacks of molecular approaches applied to this field. We sought to determine if the specific identification and counting of circulating tumor cells by cytomorphologic analysis has clinical usefulness. Peripheral blood (6 mL), treated using isolation by size of epithelial tumor cells, was obtained from 44 patients with primary liver cancer (PLC) and without metastases, 30 patients with chronic active hepatitis, 39 with liver cirrhosis, and 38 healthy individuals, and followed up for a mean period of 1 year. We searched for beta-catenin mutations in 60 single microdissected CTCs. One patient with liver cancer developed extrahepatic metastases during follow-up. CTCs and microemboli were found in 23 of the 44 patients with liver cancer and in none of the patients with chronic active hepatitis, patients with cirrhosis, or healthy subjects. Their presence was significantly associated with tumor diffusion (P =.0001) and portal tumor thrombosis (P =.006). Both the presence (P =.01) and number (P =.02) of CTCs and microemboli were significantly associated with a shorter survival. Beta-catenin mutations were found in 3 of 60 CTCs, arguing against their impact on the initial step of tumor cell invasion. In conclusion, the highly sensitive and specific detection of CTCs and microemboli may have clinical implications for cancer staging and outcome prediction. We also show the feasibility of molecular studies of individual circulating tumor cells, aimed at identifying gene mutations involved in tumor invasion.

Aged↗
PubMed2004

Portal branch ligation induces efficient retrovirus-mediated gene delivery in rat liver.

BACKGROUND: The in vivo transduction of hepatocytes with conventional retrovirus vectors requires the induction of cell division and this can currently only be achieved by invasive surgery or by inducing severe liver damage. We hypothesised that partial portal branch ligation (PBL) could induce hepatocyte proliferation and efficient gene transfer in the rat. METHODS: We ligated the portal branch serving 70% of the liver and measured the kinetics of liver mass restoration and cell proliferation and the distribution of dividing hepatocytes after administration of 5-bromo-2'-deoxyuridine. The efficiency of retrovirus-mediated gene transfer after PBL was tested by use of beta-galactosidase-expressing recombinant retroviruses. The viruses were administered in a single injection via the portal vein at different times after PBL and the livers of transduced animals were analysed 4 days later. RESULTS: We found that the number of cycling hepatocytes remained stable between 24 and 44 h after PBL (approximately 12.5%). Although there was a high level of inter-animal variability, hepatocyte proliferation was always initiated in the same lobe of the liver. In animals that had undergone PBL, 19% of hepatocytes were transduced 28 h after the administration of a single high-titre injection of retroviruses, mainly around the portal spaces. CONCLUSIONS: PBL can mediate the efficient transduction of hepatocytes in vivo after a single intravenous injection of recombinant retroviruses. This approach is feasible in humans.

Animals↗
PubMed2004

Clinical and molecular analysis of combined hepatocellular-cholangiocarcinomas.

BACKGROUND/AIMS: Combined hepatocellular-cholangiocarcinoma (HCC-CC) show dual hepatocellular and biliary epithelial differentiation. To better understand the relations between cholangiocarcinoma (CC), HCC-CC and hepatocellular carcinoma (HCC), we screened for genetic alterations. METHODS: A series of nine CC, 15 HCC-CC and three separated HCC and CC lesions ('collision tumors') were screened for loss of heterozygosity (LOH) using 400 microsatellite markers and for p53 and beta-catenin mutations. A comparison with a previously characterized series of 137 HCC was performed. RESULTS: In six cases of CC and HCC-CC, we identified TP53 gene mutations. A CTNNB1/beta-catenin was identified in two patients presenting collision tumors, but no mutations were found in CC or in HCC-CC. A high level of chromosome instability in both CC and HCC-CC was found. Recurrent specific LOH were identified at 3p and 14q in more than 50% of the CC and the HCC-CC cases, whereas these chromosomal regions were deleted in less than 10% of the HCC cases (P<10(-5)). Minimal common regions of deletion (MCRD) were defined at 3p24-p14 and 14q24-q32, respectively. CONCLUSIONS: These results suggest that combined HCC-CC are genetically closer to CC than HCC and common carcinogenesis pathways may be altered in HCC-CC and CC.

Aged↗
PubMed2004

Comparative study of human and robotic camera control in laparoscopic biliary and colon surgery.

PURPOSE: Despite the growing clinical use of active robotic camera holders there is still a lack of clinical feasibility studies. PATIENTS AND METHODS: We compared the use of a voice controlled robotic camera holder (AESOP 3000, Computer Motion, Goleta, California) to a human camera holder in a series of laparoscopic cholecystectomies and colectomies. Compliance with AESOP, abnormal operative events or complications, operative time, and the duration of hospitalization were prospectively recorded and compared to data recorded before the introduction of the robotic system. RESULTS: Compliance with AESOP was good. There were no abnormal operative events, no differences in operative time, complications, or the mean duration of hospitalization between the patients operated with a robotic or a human camera holder. CONCLUSION: The use of a robotic camera holder does not alter the length of the operative procedure, the duration of hospitalization, or postoperative morbidity. It is a safe and feasible approach to laparoscopic cholecystectomy or colectomy.

Cholecystectomy↗
PubMed2003

Clinicopathological forms and prognostic index in Budd-Chiari syndrome.

BACKGROUND: A recent study in patients with Budd-Chiari syndrome showed the value of a prognostic index including age, Pugh score, ascites and serum creatinine. Surgical portosystemic shunt did not appear to improve survival. AIMS: To validate these findings in an independent sample; to evaluate a classification into three forms according to the presence of features of acute injury, chronic lesions, or both of them (types I, II or III, respectively); and to assess whether taking into account this classification would alter our previous conclusions. METHODS: Multivariate Cox model survival analysis, first on 69 new patients; second, on these 69 and 54 previous patients, all diagnosed since 1985. RESULTS: Previous prognostic index had a significant prognostic value (P<0.0001) which was further improved by taking into account type III form (P<0.001). Type III form was associated with the poorest outcome. No significant impact of surgical shunting on survival was disclosed. CONCLUSIONS: The prognosis of Budd-Chiari syndrome can be based on age, Pugh score, ascites, serum creatinine and the presence of features indicating acute injury superimposed on chronic lesions (type III form). The idea that surgical shunting has no significant impact on survival is reinforced by these findings.

Adolescent↗
PubMed2003

Improved gene transfer selectivity to hepatocarcinoma cells by retrovirus vector displaying single-chain variable fragment antibody against c-Met.

Engineered retroviruses are widely used vectors for cancer gene therapy approaches. However, the ability to target cells of therapeutic interest while controlling the expression of the transferred genes would improve both the efficiency and the safety of viral vectors. In this study, we investigated the ability of a retroviral amphotropic envelope displaying single-chain variable-fragment (scFv) directed against the c-Met receptor, to target the entry of recombinant retroviruses to human hepatocarcinoma cells. Four single-chain antibody fragments directed against the c-Met receptor were generated and inserted into the viral envelope protein as an N-terminal fusion. The modified envelopes were incorporated into virus particles and one of the chimeric viruses, 3D6-Env, transduced preferentially human hepatoma cells rather than proliferating human hepatocytes. In another construct, the urokinase cleavage site was inserted between the scFv moiety and the envelope. Chimeric scFv-urokinase-Env viruses transduced hepatoma cells with a similar efficiency to that of the control virus and their infectivity in human hepatocytes remained low. These results indicate that amphotropic retroviruses with engineered envelopes to display scFv directed against the c-Met receptor can efficiently and selectively deliver genes into hepatoma cells.

Antibodies↗
PubMed2002

Bi-allelic inactivation of TCF1 in hepatic adenomas.

Liver adenomas are benign tumors at risk of malignant transformation. In a genome-wide search for loss of heterozygosity (LOH) associated with liver adenomas, we found a deletion in chromosome 12q in five of ten adenomas. In most cases, LOH at 12q was the only recurrent genetic alteration observed, suggesting the presence of a tumor-suppressor gene in that region. A minimal common region of deletion was defined in 12q24 that included the gene TCF1 (transcription factor 1), encoding hepatocyte nuclear factor 1 (HNF1; refs 1,2). Heterozygous germline mutations of TCF1 have been identified in individuals affected with maturity-onset diabetes of the young type 3 (MODY3; ref. 3). Bi-allelic inactivation of TCF1 was found in 10 of 16 screened adenomas, and heterozygous germline mutation were present in three affected individuals. Furthermore, 2 well-differentiated hepatocellular carcinomas (HCCs) occurring in normal liver contained somatic bi-allelic mutations of 30 screened HCCs. These results indicate that inactivation of TCF1, whether sporadic or associated with MODY3, is an important genetic event in the occurrence of human liver adenoma, and may be an early step in the development of some HCCs.

Adenoma↗
PubMed2002

Immortalization of a primate bipotent epithelial liver stem cell.

Liver regeneration after partial hepatectomy results primarily from the simple division of mature hepatocytes. However, during embryonic and fetal development or in circumstances under which postnatal hepatocytes are injured, organ regeneration is believed to occur from a compartment of epithelial liver stem or progenitor cells with biliary and hepatocytic bipotentiality. The ability to identify, isolate, and transplant epithelial liver stem cells from fetal liver would greatly facilitate the treatment of hepatic diseases currently requiring orthotopic liver transplantation. Here we report the identification and immortalization by retrovirus-mediated transfer of the simian virus 40 large T antigen gene of primate fetal epithelial liver cells with a dual hepatocytic biliary phenotype. These cells grow indefinitely in vitro and express the liver epithelial cell markers cytokeratins 8/18, the hepatocyte-specific markers albumin and alpha-fetoprotein, and the biliary-specific markers cytokeratins 7 and 19. Bipotentiality of gene expression was confirmed by clonal analysis initiated from single cells. Endogenous telomerase also is expressed constitutively. After orthotopic transplantation via the portal vein, approximately 50% of the injected cells integrated into the liver parenchyma of athymic mice without tumorigenicity. Three weeks after transplantation, cells having seeded in the liver parenchyma expressed both albumin and alpha-fetoprotein but had lost expression of cytokeratin 19. These results provide strong evidence for the existence of a bipotent epithelial liver stem cell in nonhuman primates. This unlimited source of donor cells also should enable the establishment of a model of allogenic liver cell transplantation in a large animal closely related to humans and shed light on important questions related to liver organogenesis and differentiation.

Albumins↗
PubMed2002

Specific association between alcohol intake, high grade of differentiation and 4q34-q35 deletions in hepatocellular carcinomas identified by high resolution allelotyping.

One of the most frequent deletions in hepatocellular carcinoma (HCC) is that involving the long arm of chromosome 4 (30 to 70% of the cases). These chromosomal deletions are closely related to hepatitis B virus (HBV) infection. A tumor suppressor gene (TSG) located on 4q has been proposed in liver carcinogenesis, but has not been identified as yet. Despite previous LOH studies focused on 4q in HCC, a clear minimal common region of deletion (MCRD) could not be delimited. To further investigate the role of chromosome 4q LOH in the pathogenesis of HCC, 85 microsatellite markers spanning chromosome 4q were systematically analysed in a series of 154 well-characterized primary liver tumors. In 59 tumors (38%), LOHs were observed for at least two adjacent markers. Analysis of 31 tumors demonstrating a partial or interstitial 4q deletion allowed to define three MCRDs of 15, 9 and 8 Mb at the 4q22, 4q34 and 4q35 regions, respectively. Seven putative candidate genes located in 4q22, DAPP1, BMPR1B, PKD2, HERC3, SMARCAD1, CEB1 and ENH were screened for mutations but no somatic alterations were identified. Search for relationships between the specific regions of deletion and clinical parameters showed a significant association between loss of the 4q34-35 region with alcohol intake (P=0.005) and with high grade of differentiation (P=0.02). These results are in contrast with the close association between HBV infection and the whole 4q LOH and reveal heterogeneity of 4q LOH in relation to different risk factors. In the light of these new findings, which link different 4q LOH regions to different etiologic factors, the molecular mechanisms underlying 4q deletions in HCC and the targeted gene(s) remain to be identified.

Alleles↗