In vivo imaging of prostate cancer using an anti-PSMA scFv fragment as a probe

AbstractWe aimed to evaluate a fluorescent-labeled single chain variable fragment (scFv) of the anti-PSMA antibody as a specific probe for the detection of prostate cancer by in vivo fluorescence imaging. An orthotopic model of prostate cancer was generated by injecting LNCaP cells into the prostate lobe. ScFvD2B, a high affinity anti-PSMA antibody fragment, was labeled using a near-infrared fluorophore to generate a specific imaging probe (X770-scFvD2B). PSMA-unrelated scFv-X770 was used as a control. Probes were injected intravenously into mice with prostate tumors and fluorescence was monitored in vivo by fluorescence molecular tomography (FMT). In vitro assays showed that X770-scFvD2B specifically bound to PSMA and was internalized in PSMA-expressing LNCaP cells. After intravenous injection, X770-scFvD2B was detected in vivo by FMT in the prostate region. On excised prostates the scFv probe co-localized with the cancer cells and was found internalized in PSMA-expressing cells. The PSMA-unrelated scFv used as a control did not label the prostate cancer cells. Our data demonstrated that scFvD2B is a high affinity contrast agent for in vivo detection of PSMA-expressing cells in the prostate. NIR-labeled scFvD2B could thus be further developed as a clinical probe for imaging-guided targeted biopsies

Proteomic Profiling of Hepatocellular Adenomas Paves the Way to Diagnostic and Prognostic Approaches

Background and Aims : Through an exploratory proteomic approach based on typical hepatocellular adenomas (HCAs), we previously identified a diagnostic biomarker for a distinctive subtype of HCA with high risk of bleeding, already validated on a multicenter cohort. We hypothesized that the whole protein expression deregulation profile could deliver much more informative data for tumor characterization. Therefore, we pursued our analysis with the characterization of HCA proteomic profiles, evaluating their correspondence with the established genotype/phenotype classification and assessing whether they could provide added diagnosis and prognosis values. Approach and Results : From a collection of 260 cases, we selected 52 typical cases of all different subgroups on which we built a reference HCA proteomics database. Combining laser microdissection and mass-spectrometry–based proteomic analysis, we compared the relative protein abundances between tumoral (T) and nontumoral (NT) liver tissues from each patient and we defined a specific proteomic profile of each of the HCA subgroups. Next, we built a matching algorithm comparing the proteomic profile extracted from a patient with our reference HCA database. Proteomic profiles allowed HCA classification and made diagnosis possible, even for complex cases with immunohistological or genomic analysis that did not lead to a formal conclusion. Despite a well-established pathomolecular classification, clinical practices have not substantially changed and the HCA management link to the assessment of the malignant transformation risk remains delicate for many surgeons. That is why we also identified and validated a proteomic profile that would directly evaluate malignant transformation risk regardless of HCA subtype. Conclusions : This work proposes a proteomic-based machine learning tool, operational on fixed biopsies, that can improve diagnosis and prognosis and therefore patient management for HCAs.European Funds for Regional Development (Feder), N° Presage 3207

Biomedicines

Antibody-mediated rejection (ABMR) is the leading cause of allograft failure in kidney transplantation. Its histological hallmark is represented by lesions of glomerulitis i.e., inflammatory cells within glomeruli. Current therapies for ABMR fail to prevent chronic allograft damage i.e., transplant glomerulopathy, leading to allograft loss. We used laser microdissection of glomeruli from formalin-fixed allograft biopsies combined with mass spectrometry-based proteomics to describe the proteome modification of 11 active and 10 chronic active ABMR cases compared to 8 stable graft controls. Of 1335 detected proteins, 77 were deregulated in glomerulitis compared to stable grafts, particularly involved in cellular stress mediated by interferons type I and II, leukocyte activation and microcirculation remodeling. Three proteins extracted from this protein profile, TYMP, WARS1 and GBP1, showed a consistent overexpression by immunohistochemistry in glomerular endothelial cells that may represent relevant markers of endothelial stress during active ABMR. In transplant glomerulopathy, 137 proteins were deregulated, which favor a complement-mediated mechanism, wound healing processes through coagulation activation and ultimately a remodeling of the glomerular extracellular matrix, as observed by light microscopy. This study brings novel information on glomerular proteomics of ABMR in kidney transplantation, and highlights potential targets of diagnostic and therapeutic interest

ASS1 Overexpression:A Hallmark of Sonic Hedgehog Hepatocellular Adenomas; Recommendations for Clinical Practice

Until recently, 10% of hepatocellular adenomas (HCAs) remained unclassified (UHCA). Among the UHCAs, the sonic hedgehog HCA (shHCA) was defined by focal deletions that fuse the promoter of Inhibin beta E chain with GLI1. Prostaglandin D2 synthase was proposed as immunomarker. In parallel, our previous work using proteomic analysis showed that most UHCAs constitute a homogeneous subtype associated with overexpression of argininosuccinate synthase (ASS1). To clarify the use of ASS1 in the HCA classification and avoid misinterpretations of the immunohistochemical staining, the aims of this work were to study (1) the link between shHCA and ASS1 overexpression and (2) the clinical relevance of ASS1 overexpression for diagnosis. Molecular, proteomic, and immunohistochemical analyses were performed in UHCA cases of the Bordeaux series. The clinico-pathological features, including ASS1 immunohistochemical labeling, were analyzed on a large international series of 67 cases. ASS1 overexpression and the shHCA subgroup were superimposed in 15 cases studied by molecular analysis, establishing ASS1 overexpression as a hallmark of shHCA. Moreover, the ASS1 immunomarker was better than prostaglandin D2 synthase and only found positive in 7 of 22 shHCAs. Of the 67 UHCA cases, 58 (85.3%) overexpressed ASS1, four cases were ASS1 negative, and in five cases ASS1 was noncontributory. Proteomic analysis performed in the case of doubtful interpretation of ASS1 overexpression, especially on biopsies, can be a support to interpret such cases. ASS1 overexpression is a specific hallmark of shHCA known to be at high risk of bleeding. Therefore, ASS1 is an additional tool for HCA classification and clinical diagnosis

Overview of Alpha-1 Antitrypsin Deficiency- Mediated Liver Disease

International audienc

In vivo silencing of Reptin blocks the progression of human hepatocellular carcinoma in xenografts and is associated with replicative senescence.: Reptin silencing blocks liver cancer progression

International audienceBACKGROUND & AIMS: We previously showed that Reptin is overexpressed in hepatocellular carcinoma (HCC), and that in vitro depletion of Reptin with siRNAs led to HCC cell growth arrest and apoptosis. Here, we asked whether in vivo targeting of Reptin in established tumours had a therapeutic effect. METHODS: We used lentiviral vectors to construct HuH7 and Hep3B cell lines with doxycycline (Dox)-dependent expression of Reptin (R2) or control shRNA (GL2). Cells were injected subcutaneously into immunodeficient mice, and Dox was given when tumours reached a volume of 250 mm(3). RESULTS: In vitro, the growth of GL2-Dox, GL2+Dox, and R2-Dox cells was undistinguishable whereas that of R2+Dox cells stopped 4 days after Dox treatment. The growth decrease was associated with increased apoptosis, and evidence of replicative senescence, as shown by staining for acid beta-galactosidase and the presence of senescence-associated heterochromatin foci. In xenografted mice, R2+Dox tumour growth stagnated or even regressed with prolonged treatment in contrast with the GL2-Dox, GL2+Dox, and R2-Dox tumours that progressed steadily. The blockage of tumour progression was associated with the induction of senescence and reduced cell proliferation. CONCLUSIONS: In vivo Reptin depletion leads to tumour growth arrest. Reptin may prove a valuable target in HCC

Halofuginone suppresses the lung metastasis of chemically induced hepatocellular carcinoma in rats through MMP inhibition

Halofuginone, an inhibitor of collagen synthesis, appears to be a promising antitumoral drug in preclinical studies. We used a relevant rat model of autochthonous, chemically induced, spontaneously metastasizing hepatocellular carcinoma (HCC) to test the efficacy of halofuginone on tumor progression and matrix metalloproteinase (MMP) expression. Following sequential administration of diethylnitrosamine and N-nitrosomorpholine for 14 weeks, all animals developed HCC and then received halofuginone or its solvent for 10 weeks. The final number of liver tumors was lower in the halofuginone group than in the solvent group (57.2 ± 4.6 vs 68 ± 5.0; P < .01). The percentage of the lung surface infiltrated by metastasis was much smaller in the halofuginone group (0.3 ± 0.2%) than in the solvent group (13.5 ± 10.1%; P < .02). MMP-9 activity was decreased in the halofuginone group by 89% and 63% in non-neoplastic parts of the liver and tumor, respectively. The percentage of active MMP-2 was reduced by 90% in non-neoplastic parts of the liver and by 61% in tumors. This was likely subsequent to a decreased expression of both MMP-14 and tissue inhibitor of matrix metalloproteinase-2, which are required for pro-MMP-2 activation. These results, obtained from a clinically relevant model, further suggest the potential benefit of halofuginone in HCC

Cancer Gene Ther

Rnd3/RhoE is an atypical Rho GTPase family member, known to be deregulated in many types of cancer. Previously, we showed that RND3 expression is downregulated in hepatocellular carcinoma (HCC) cell lines and tissues. In cancer cells, Rnd3 is involved in the regulation of cell proliferation and cell invasion. The implication of Rnd3 in HCC invasion was importantly studied whereas its role in cell growth needs further investigation. Thus, in this work, we aimed to better understand the impact of Rnd3 on tumor hepatocyte proliferation. Our results indicate that the silencing of RND3 induces a cell growth arrest both in vitro in 2D and 3D culture conditions and in vivo in tumor xenografts. The growth alteration after RND3 silencing in HCC cells is not due to an increase of cell death but to the induction of senescence. This RND3 knockdown-mediated phenomenon is dependent on the decrease of hTERT expression. Interestingly, after re-expression of RND3, these cells are able to bypass senescence and regain the ability to proliferate, with a re-expression of hTERT. Given that a low expression of Rnd3 is linked to the presence of satellite nodules in HCC, the transient senescence state observed might play a role in cancer progression

Tracking cellular and molecular changes in a species-specific manner during experimental tumor progression <i>in vivo</i>

International audienceHepatoblastoma (HBL) is a pediatric liver cancer with defined molecular alterations driving its progression. Here, we describe an animal model for HBL on the chick chorioallantoic membrane (CAM), which recapitulates relevant features of HBL in patients. Expression of classic tumor-associated proteins such as β-catenin, EpCAM and CK19 was maintained in acini-like organized tumors on CAM, as was synthesis of AFP, a tumor marker used for monitoring patient response. RNA sequencing revealed an unexpected molecular evolution of HBL cells on the CAM, with significant deregulation of more than 6,000 genes including more than half of all HOX genes. Bioinformatic analysis distinguish between tumor cell-expressed genes and chick genes, thereby shedding new light on the complex interactions taking place during HBL progression. Importantly, human tumor suppressive ribosomal genes were downregulated after implantation, whereas mitochondrial genes encoding for anti-apoptotic peptides were strongly induced in vivo. Meprin-1α expression was increased during evolution of CAM tumors and confirmed by immunohistochemistry. Cisplatin, a commonly used chemotherapeutic agent for HBL, showed significant anti-tumoral effects. Our results broaden the understanding of the molecular adaptation process of human cancer cells to the microenvironment and might help to elaborate novel therapeutic concepts for the treatment of this pediatric liver tumor

Protease-activated receptor 1 knockout reduces experimentally induced liver fibrosis.

International audienceThrombin inhibition protects against liver fibrosis. However, it is not known whether the thrombin profibrogenic effect is due to effects on blood coagulation or to signaling via protease-activated receptors (PARs). We took advantage of the lack of blood coagulation defects in PAR-1-knockout mice. Acute carbon tetrachloride (CCl(4)) toxicity was similar in wild-type (WT), PAR-1(-/-), and PAR-1(+/-) mice as judged by aminotransferase levels, area of liver necrosis, and liver peroxidation measured by Fourier-transformed infrared spectroscopy. Fifteen mice/group received CCl(4) or its solvent for 6 wk (300 microl/kg, 3 times a week). Fibrosis area was increased 10-fold by CCl(4) treatment in WT mice. PAR-1 deficiency protected against fibrosis, with 36% and 56% decrease in PAR-1(+/-) and PAR-1(-/-) mice, respectively (P < 0.001). Similar results were obtained for area of activated fibrogenic cells (64% and 79% decrease in PAR-1(+/-) and PAR-1(-/-) mice, respectively, P < 0.001). These findings were corroborated by measurements of type I collagen, matrix metalloproteinase-2, and PDGF-beta receptor mRNA levels. There was also a significant decrease in T lymphocyte infiltration in PAR-1-deficient mice. Altogether, these results suggest that thrombin profibrogenic effects are independent of effects on blood coagulation and are instead due to direct effects on fibrogenic cells and possibly on T lymphocytes