Bi-Functional Peptides as a New Therapeutic Tool for Hepatocellular Carcinoma

Background: The interfering peptides that block protein–protein interactions have been receiving increasing attention as potential therapeutic tools. Methods: We measured the internalization and biological effect of four bi-functional tumor-penetrating and interfering peptides into primary hepatocytes isolated from three non-malignant and 11 hepatocellular carcinomas. Results: These peptides are internalized in malignant hepatocytes but not in non-malignant cells. Furthermore, the degree of peptide internalization correlated with receptor expression level and tumor aggressiveness levels. Importantly, penetration of the peptides iRGD-IP, LinTT1-IP, TT1-IP, and RPARPAR-IP induced apoptosis of the malignant hepatocytes without effect on non-malignant cells. Conclusion: Receptor expression levels correlated with the level of peptide internalization and aggressiveness of the tumor. This study highlights the potential to exploit the expression of tumor-penetrating peptide receptors as a predictive marker of liver tumor aggressiveness. These bi-functional peptides could be developed for personalized tumor treatment

Intérêt des peptides bi-fonctionnels dans le traitement des cancers. Application au carcinome hépatocellulaire

Malignant tumours are the leading cause of death in industrialized countries. Among solid tumours, hepatocellular carcinoma (HCC) is the 4th leading cause of death worldwide and its incidence is increasing. Peptides are small amino acids chains whose biological properties can be used in therapeutics, including that of interfering between two proteins, which are interfering peptides (IP). Other peptides have the property of crossing biological or cellular membranes, named cell penetrating peptides (CPP), among them some penetrate tumor tissues only, that are tumor-penetrating peptides (TPP). The combination of a TPP with an IP produces bi-functional peptides (TPP-IP). The purpose of this thesis was to study the efficacy of TPP-IP in models of human chronic lymphoid leukemia (CLL), in-vitro and in-vivo and human HCC cells. The results were published in 6 articles were as follows: • From proteins whose interactions are known, the PEPscan technique, inexpensive and fast, made possible to identify a relatively small number of IP candidates. PEPscan results were compared to an in silico modelling system. Subject to the available structural information about proteins, these two methods are consistent and encouraging. • The site of interaction between TPP and the NRP-1 membrane receptor is located on the b1 domain of NRP-1 by in silico modelling. • C9h is an IP that interferes between PP2A and Caspase 9 proteins. The affinity constant between C9h and PP2A was measured and was close to the affinity constant between PP2A and Caspase 9. • TTPs (iRGD, LinTT1, TT1, and RPARPAR) with or without an IP that blocks the interaction between PP2A and SET, was internalized into the B cells of patients with CLL and HCC hepatocytes and induced apoptosis. Conversely, internalization was minimal in normal B cells or hepatocytes. These 4 TPP-IPs were weakly degraded in human serum. iRGD-IP significantly increased survival in a murine xenograft model of LLC. • The 4 bi-functional peptides (iRGD-IP, RPAR-IP, LinTT1-IP, TT1-IP) (IP blocked the PP2A/SET interaction) were tested on malignant or non-malignant hepatocytes and peptide internalization was logarithmically correlated with the amount of receptor expressed on the cell surface as well as a tumor aggressiveness score. Internalization led to apoptosis of malignant hepatocytes only. • TT1-IP and LinTT1-IP (IP blocked the PP2A/SET interaction) extended the survival of immunodeficient mice grafted with a human LLC tumour line, but only TT1-IP had a significant effect. In vivo uptake of fluorescent Cy7 labelled TT1-IP was greater in a mouse with CLL cells. In this model, RPARPAR-IP had no effect on survival. However, tumour cell-induced apoptosis by TT1-IP, LinTT1-IP and RPARPAR-IP was similar. No apoptotic effect was observed with IP alone or TT1 alone or on healthy cells. This last result demonstrated the complementary roles of TPP and IP in achieving specific tumor cell apoptosis. In immunocompetent mice, no toxicity of TT1-IP was observed. Following an intraperitoneal injection, the plasma concentration reached a maximum peak within 10 minutes before a plasmatic clearance of 28 minutes half-time life. In human serum incubation, 40% of TT1-IP was detectable after 6h showing its slow degradation by proteolysis. In summary, the results obtained in this thesis suggest that the use of therapeutic peptides in cancer treatment is a real possibility. The immediate prospect is to test these bi-functional peptides on a HCC murine xenograft models for pre-clinical validation.Les tumeurs malignes sont la première cause de mortalité dans les pays industrialisés. Parmi les tumeurs solides, le carcinome hépatocellulaire (CHC) est la 4ème cause de décès dans le monde et son incidence progresse. Les peptides sont de courtes chaines d'acides aminés dont les propriétés biologiques peuvent être utilisés en thérapeutiques. Ainsi les peptides interférant (IP) ont la propriété de bloquer l'interaction entre 2 protéines. D'autres peptides ont la propriété de franchir les membranes biologiques ou cellulaires, les cell penetrating peptides (CPP), parmi lesquels certains ne pénètrent que dans les tissus tumoraux, les tumor-penetrating peptides (TPP). La combinaison d'un TPP avec un IP produit des peptides bi-fonctionnel (TPP-IP). Le but de cette thèse était d'étudier l'efficacité des TPP-IP dans des modèles de leucémie lymphoïde chronique humaine (LLC), in-vitro et in-vivo et des cellules humaines de CHC. Les résultats obtenus, publiés dans 6 articles étaient les suivants : • A partir de protéines dont les interactions sont connues, la technique du PEPscan, permettait d'identifier des candidats IP en nombre relativement faible. Les résultats du PEPscan ont été comparés à des modélisations in silico. Sous réserve des informations structurelles disponibles sur les protéines, ces 2 méthodes sont concordantes et encourageantes. • Le site d'interaction entre les TPP et le récepteur membranaire NRP-1 est situé sur le domaine b1 de NRP-1 par modélisation in silico. • C9h est un IP qui interfère entre les protéines PP2A et Caspase 9. La constante d'affinité entre C9h et PP2A a été mesurée et était proche de la constante d'affinité entre PP2A et Caspase 9. • Les TTP (iRGD, LinTT1, TT1 et RPARPAR) avec ou sans un IP qui bloque l'interaction entre PP2A et SET, pouvaient pénétrer dans les cellules B des patients souffrants de LLC et dans les hépatocytes de CHC et induisaient une apoptose. Inversement, l'internalisation était minime dans les cellules B ou hépatocytes normaux. Ces 4 TPP-IP étaient faiblement dégradés dans du sérum humain. L'iRGD-IP augmentait significativement la survie dans un modèle murin de xénogreffe de LLC. • Les 4 peptides bi-fonctionnels (iRGD-IP, RPARPAR-IP, LinTT1-IP, TT1-IP) (IP bloque l'interaction PP2A/SET) ont été testés sur hépatocytes malins ou non et l'internalisation peptidique était corrélée de manière logarithmique à la quantité de récepteur exprimée à la surface des cellules ainsi qu'à un score d'agressivité tumorale. L'internalisation induisait une apoptose des hépatocytes malins uniquement. • TT1-IP et LinTT1-IP prolongeaient la survie de souris immunodéficientes greffées avec une lignée tumorale humaine de LLC, mais seul TT1-IP avait un effet significatif. La captation in-vivo de TT1-IP fluorescent après marquage par le Cy7, était plus importante chez une souris porteuse de cellules de LLC. Dans ce modèle, RPARPAR-IP n'avait pas d'effet sur la survie. Pourtant, l'apoptose induite sur les cellules tumorales par TT1-IP, LinTT1-IP et RPARPAR-IP était comparable. Aucun effet apoptotique n'a été observé avec IP seul ou TT1 seul ou sur des cellules saines. Ces derniers résultats démontraient les rôles complémentaires du TPP et de l'IP pour obtenir une apoptose spécifique des cellules tumorales. Sur les souris immunocompétentes nous n'avons pas observé de toxicité de TT1-IP. L'injection intra-péritonéale était suivie d'une concentration plasmatique maximale atteinte en 10 minutes puis d'une clairance plasmatique avec un temps de ½ vie de 28 minutes. Dans du sérum humain, 40% de TT1-IP était détectable après 6h d'incubation montrant ainsi sa lente dégradation par protéolyse. En résumé, les résultats obtenus dans cette thèse laissent penser que l'utilisation de peptides thérapeutiques dans le traitement des cancers est une possibilité réelle. La perspective immédiate est de tester ces peptides bi-fonctionnels sur des modèles murins de xénogreffes de CHC dans un but de validation pré-clinique

Bi-functional peptides : interest in cancer treatment. Application to hepatocellular carcinoma

Les tumeurs malignes sont la première cause de mortalité dans les pays industrialisés. Parmi les tumeurs solides, le carcinome hépatocellulaire (CHC) est la 4ème cause de décès dans le monde et son incidence progresse. Les peptides sont de courtes chaines d'acides aminés dont les propriétés biologiques peuvent être utilisés en thérapeutiques. Ainsi les peptides interférant (IP) ont la propriété de bloquer l'interaction entre 2 protéines. D'autres peptides ont la propriété de franchir les membranes biologiques ou cellulaires, les cell penetrating peptides (CPP), parmi lesquels certains ne pénètrent que dans les tissus tumoraux, les tumor-penetrating peptides (TPP). La combinaison d'un TPP avec un IP produit des peptides bi-fonctionnel (TPP-IP). Le but de cette thèse était d'étudier l'efficacité des TPP-IP dans des modèles de leucémie lymphoïde chronique humaine (LLC), in-vitro et in-vivo et des cellules humaines de CHC. Les résultats obtenus, publiés dans 6 articles étaient les suivants : • A partir de protéines dont les interactions sont connues, la technique du PEPscan, permettait d'identifier des candidats IP en nombre relativement faible. Les résultats du PEPscan ont été comparés à des modélisations in silico. Sous réserve des informations structurelles disponibles sur les protéines, ces 2 méthodes sont concordantes et encourageantes. • Le site d'interaction entre les TPP et le récepteur membranaire NRP-1 est situé sur le domaine b1 de NRP-1 par modélisation in silico. • C9h est un IP qui interfère entre les protéines PP2A et Caspase 9. La constante d'affinité entre C9h et PP2A a été mesurée et était proche de la constante d'affinité entre PP2A et Caspase 9. • Les TTP (iRGD, LinTT1, TT1 et RPARPAR) avec ou sans un IP qui bloque l'interaction entre PP2A et SET, pouvaient pénétrer dans les cellules B des patients souffrants de LLC et dans les hépatocytes de CHC et induisaient une apoptose. Inversement, l'internalisation était minime dans les cellules B ou hépatocytes normaux. Ces 4 TPP-IP étaient faiblement dégradés dans du sérum humain. L'iRGD-IP augmentait significativement la survie dans un modèle murin de xénogreffe de LLC. • Les 4 peptides bi-fonctionnels (iRGD-IP, RPARPAR-IP, LinTT1-IP, TT1-IP) (IP bloque l'interaction PP2A/SET) ont été testés sur hépatocytes malins ou non et l'internalisation peptidique était corrélée de manière logarithmique à la quantité de récepteur exprimée à la surface des cellules ainsi qu'à un score d'agressivité tumorale. L'internalisation induisait une apoptose des hépatocytes malins uniquement. • TT1-IP et LinTT1-IP prolongeaient la survie de souris immunodéficientes greffées avec une lignée tumorale humaine de LLC, mais seul TT1-IP avait un effet significatif. La captation in-vivo de TT1-IP fluorescent après marquage par le Cy7, était plus importante chez une souris porteuse de cellules de LLC. Dans ce modèle, RPARPAR-IP n'avait pas d'effet sur la survie. Pourtant, l'apoptose induite sur les cellules tumorales par TT1-IP, LinTT1-IP et RPARPAR-IP était comparable. Aucun effet apoptotique n'a été observé avec IP seul ou TT1 seul ou sur des cellules saines. Ces derniers résultats démontraient les rôles complémentaires du TPP et de l'IP pour obtenir une apoptose spécifique des cellules tumorales. Sur les souris immunocompétentes nous n'avons pas observé de toxicité de TT1-IP. L'injection intra-péritonéale était suivie d'une concentration plasmatique maximale atteinte en 10 minutes puis d'une clairance plasmatique avec un temps de ½ vie de 28 minutes. Dans du sérum humain, 40% de TT1-IP était détectable après 6h d'incubation montrant ainsi sa lente dégradation par protéolyse. En résumé, les résultats obtenus dans cette thèse laissent penser que l'utilisation de peptides thérapeutiques dans le traitement des cancers est une possibilité réelle. La perspective immédiate est de tester ces peptides bi-fonctionnels sur des modèles murins de xénogreffes de CHC dans un but de validation pré-clinique.Malignant tumours are the leading cause of death in industrialized countries. Among solid tumours, hepatocellular carcinoma (HCC) is the 4th leading cause of death worldwide and its incidence is increasing. Peptides are small amino acids chains whose biological properties can be used in therapeutics, including that of interfering between two proteins, which are interfering peptides (IP). Other peptides have the property of crossing biological or cellular membranes, named cell penetrating peptides (CPP), among them some penetrate tumor tissues only, that are tumor-penetrating peptides (TPP). The combination of a TPP with an IP produces bi-functional peptides (TPP-IP). The purpose of this thesis was to study the efficacy of TPP-IP in models of human chronic lymphoid leukemia (CLL), in-vitro and in-vivo and human HCC cells. The results were published in 6 articles were as follows: • From proteins whose interactions are known, the PEPscan technique, inexpensive and fast, made possible to identify a relatively small number of IP candidates. PEPscan results were compared to an in silico modelling system. Subject to the available structural information about proteins, these two methods are consistent and encouraging. • The site of interaction between TPP and the NRP-1 membrane receptor is located on the b1 domain of NRP-1 by in silico modelling. • C9h is an IP that interferes between PP2A and Caspase 9 proteins. The affinity constant between C9h and PP2A was measured and was close to the affinity constant between PP2A and Caspase 9. • TTPs (iRGD, LinTT1, TT1, and RPARPAR) with or without an IP that blocks the interaction between PP2A and SET, was internalized into the B cells of patients with CLL and HCC hepatocytes and induced apoptosis. Conversely, internalization was minimal in normal B cells or hepatocytes. These 4 TPP-IPs were weakly degraded in human serum. iRGD-IP significantly increased survival in a murine xenograft model of LLC. • The 4 bi-functional peptides (iRGD-IP, RPAR-IP, LinTT1-IP, TT1-IP) (IP blocked the PP2A/SET interaction) were tested on malignant or non-malignant hepatocytes and peptide internalization was logarithmically correlated with the amount of receptor expressed on the cell surface as well as a tumor aggressiveness score. Internalization led to apoptosis of malignant hepatocytes only. • TT1-IP and LinTT1-IP (IP blocked the PP2A/SET interaction) extended the survival of immunodeficient mice grafted with a human LLC tumour line, but only TT1-IP had a significant effect. In vivo uptake of fluorescent Cy7 labelled TT1-IP was greater in a mouse with CLL cells. In this model, RPARPAR-IP had no effect on survival. However, tumour cell-induced apoptosis by TT1-IP, LinTT1-IP and RPARPAR-IP was similar. No apoptotic effect was observed with IP alone or TT1 alone or on healthy cells. This last result demonstrated the complementary roles of TPP and IP in achieving specific tumor cell apoptosis. In immunocompetent mice, no toxicity of TT1-IP was observed. Following an intraperitoneal injection, the plasma concentration reached a maximum peak within 10 minutes before a plasmatic clearance of 28 minutes half-time life. In human serum incubation, 40% of TT1-IP was detectable after 6h showing its slow degradation by proteolysis. In summary, the results obtained in this thesis suggest that the use of therapeutic peptides in cancer treatment is a real possibility. The immediate prospect is to test these bi-functional peptides on a HCC murine xenograft models for pre-clinical validation

Intérêt des peptides bi-fonctionnels dans le traitement des cancers. Application au carcinome hépatocellulaire

Malignant tumours are the leading cause of death in industrialized countries. Among solid tumours, hepatocellular carcinoma (HCC) is the 4th leading cause of death worldwide and its incidence is increasing. Peptides are small amino acids chains whose biological properties can be used in therapeutics, including that of interfering between two proteins, which are interfering peptides (IP). Other peptides have the property of crossing biological or cellular membranes, named cell penetrating peptides (CPP), among them some penetrate tumor tissues only, that are tumor-penetrating peptides (TPP). The combination of a TPP with an IP produces bi-functional peptides (TPP-IP). The purpose of this thesis was to study the efficacy of TPP-IP in models of human chronic lymphoid leukemia (CLL), in-vitro and in-vivo and human HCC cells. The results were published in 6 articles were as follows: • From proteins whose interactions are known, the PEPscan technique, inexpensive and fast, made possible to identify a relatively small number of IP candidates. PEPscan results were compared to an in silico modelling system. Subject to the available structural information about proteins, these two methods are consistent and encouraging. • The site of interaction between TPP and the NRP-1 membrane receptor is located on the b1 domain of NRP-1 by in silico modelling. • C9h is an IP that interferes between PP2A and Caspase 9 proteins. The affinity constant between C9h and PP2A was measured and was close to the affinity constant between PP2A and Caspase 9. • TTPs (iRGD, LinTT1, TT1, and RPARPAR) with or without an IP that blocks the interaction between PP2A and SET, was internalized into the B cells of patients with CLL and HCC hepatocytes and induced apoptosis. Conversely, internalization was minimal in normal B cells or hepatocytes. These 4 TPP-IPs were weakly degraded in human serum. iRGD-IP significantly increased survival in a murine xenograft model of LLC. • The 4 bi-functional peptides (iRGD-IP, RPAR-IP, LinTT1-IP, TT1-IP) (IP blocked the PP2A/SET interaction) were tested on malignant or non-malignant hepatocytes and peptide internalization was logarithmically correlated with the amount of receptor expressed on the cell surface as well as a tumor aggressiveness score. Internalization led to apoptosis of malignant hepatocytes only. • TT1-IP and LinTT1-IP (IP blocked the PP2A/SET interaction) extended the survival of immunodeficient mice grafted with a human LLC tumour line, but only TT1-IP had a significant effect. In vivo uptake of fluorescent Cy7 labelled TT1-IP was greater in a mouse with CLL cells. In this model, RPARPAR-IP had no effect on survival. However, tumour cell-induced apoptosis by TT1-IP, LinTT1-IP and RPARPAR-IP was similar. No apoptotic effect was observed with IP alone or TT1 alone or on healthy cells. This last result demonstrated the complementary roles of TPP and IP in achieving specific tumor cell apoptosis. In immunocompetent mice, no toxicity of TT1-IP was observed. Following an intraperitoneal injection, the plasma concentration reached a maximum peak within 10 minutes before a plasmatic clearance of 28 minutes half-time life. In human serum incubation, 40% of TT1-IP was detectable after 6h showing its slow degradation by proteolysis. In summary, the results obtained in this thesis suggest that the use of therapeutic peptides in cancer treatment is a real possibility. The immediate prospect is to test these bi-functional peptides on a HCC murine xenograft models for pre-clinical validation.Les tumeurs malignes sont la première cause de mortalité dans les pays industrialisés. Parmi les tumeurs solides, le carcinome hépatocellulaire (CHC) est la 4ème cause de décès dans le monde et son incidence progresse. Les peptides sont de courtes chaines d'acides aminés dont les propriétés biologiques peuvent être utilisés en thérapeutiques. Ainsi les peptides interférant (IP) ont la propriété de bloquer l'interaction entre 2 protéines. D'autres peptides ont la propriété de franchir les membranes biologiques ou cellulaires, les cell penetrating peptides (CPP), parmi lesquels certains ne pénètrent que dans les tissus tumoraux, les tumor-penetrating peptides (TPP). La combinaison d'un TPP avec un IP produit des peptides bi-fonctionnel (TPP-IP). Le but de cette thèse était d'étudier l'efficacité des TPP-IP dans des modèles de leucémie lymphoïde chronique humaine (LLC), in-vitro et in-vivo et des cellules humaines de CHC. Les résultats obtenus, publiés dans 6 articles étaient les suivants : • A partir de protéines dont les interactions sont connues, la technique du PEPscan, permettait d'identifier des candidats IP en nombre relativement faible. Les résultats du PEPscan ont été comparés à des modélisations in silico. Sous réserve des informations structurelles disponibles sur les protéines, ces 2 méthodes sont concordantes et encourageantes. • Le site d'interaction entre les TPP et le récepteur membranaire NRP-1 est situé sur le domaine b1 de NRP-1 par modélisation in silico. • C9h est un IP qui interfère entre les protéines PP2A et Caspase 9. La constante d'affinité entre C9h et PP2A a été mesurée et était proche de la constante d'affinité entre PP2A et Caspase 9. • Les TTP (iRGD, LinTT1, TT1 et RPARPAR) avec ou sans un IP qui bloque l'interaction entre PP2A et SET, pouvaient pénétrer dans les cellules B des patients souffrants de LLC et dans les hépatocytes de CHC et induisaient une apoptose. Inversement, l'internalisation était minime dans les cellules B ou hépatocytes normaux. Ces 4 TPP-IP étaient faiblement dégradés dans du sérum humain. L'iRGD-IP augmentait significativement la survie dans un modèle murin de xénogreffe de LLC. • Les 4 peptides bi-fonctionnels (iRGD-IP, RPARPAR-IP, LinTT1-IP, TT1-IP) (IP bloque l'interaction PP2A/SET) ont été testés sur hépatocytes malins ou non et l'internalisation peptidique était corrélée de manière logarithmique à la quantité de récepteur exprimée à la surface des cellules ainsi qu'à un score d'agressivité tumorale. L'internalisation induisait une apoptose des hépatocytes malins uniquement. • TT1-IP et LinTT1-IP prolongeaient la survie de souris immunodéficientes greffées avec une lignée tumorale humaine de LLC, mais seul TT1-IP avait un effet significatif. La captation in-vivo de TT1-IP fluorescent après marquage par le Cy7, était plus importante chez une souris porteuse de cellules de LLC. Dans ce modèle, RPARPAR-IP n'avait pas d'effet sur la survie. Pourtant, l'apoptose induite sur les cellules tumorales par TT1-IP, LinTT1-IP et RPARPAR-IP était comparable. Aucun effet apoptotique n'a été observé avec IP seul ou TT1 seul ou sur des cellules saines. Ces derniers résultats démontraient les rôles complémentaires du TPP et de l'IP pour obtenir une apoptose spécifique des cellules tumorales. Sur les souris immunocompétentes nous n'avons pas observé de toxicité de TT1-IP. L'injection intra-péritonéale était suivie d'une concentration plasmatique maximale atteinte en 10 minutes puis d'une clairance plasmatique avec un temps de ½ vie de 28 minutes. Dans du sérum humain, 40% de TT1-IP était détectable après 6h d'incubation montrant ainsi sa lente dégradation par protéolyse. En résumé, les résultats obtenus dans cette thèse laissent penser que l'utilisation de peptides thérapeutiques dans le traitement des cancers est une possibilité réelle. La perspective immédiate est de tester ces peptides bi-fonctionnels sur des modèles murins de xénogreffes de CHC dans un but de validation pré-clinique

Liver transplant from controlled donation after circulatory death donors with normothermic regional perfusion versus donation after drain death donors

International audienceWe read with great interest the recent article of Ruiz et al.(1) and would like to congratulate the authors. Also, we would like to make some important comments. Ruiz et al. reported the outcomes of liver transplantation (LT) from controlled donation after circulatory death (cDCD) donors with normothermic regional perfusion (NRP) (from 2015 to 2019, 100 patient) versus donation after brain death (DBD) donors (from 2015 to 2019, 200 patients)

Pepscan Approach for the Identification of Protein–Protein Interfaces: Lessons from Experiment

International audiencePEPscan is an old approach that has recently gained renewed interest for the identification of interfering peptides (IPs), i.e., peptides able to interfere with protein–protein interactions (PPIs). Its principle is to slice a protein sequence as a series of short overlapping peptides that are synthesized on a peptide array and tested for their ability to bind a partner, with positive spots corresponding to candidate IPs. PEPscan has been applied with a rather large success in various contexts, but the structural determinants underlying this success remain obscure. Here, we analyze the results of 14 PEPscan experiments, and confront the in vitro results with the available structural information. PEPscan identifies candidate IPs in limited numbers that in all cases correspond to solvent-accessible regions of the structures, their location at the protein–protein interface remaining to be further demonstrated. A strong point of PEPscan seems to be its ability to identify specific IPs. IPs identified from the same protein differ depending on the target PPI, and correspond to patches not frequently involved in the interactions seen in the 3D structures available. Overall, PEPscan seems to provide a cheap and rapid manner to identify candidate IPs, that also comes with room for improvement

Fusion of the midplane with the left intersectional plane: a liver anatomical variation revisited with multidetector-row CT.

This article updates the description of an anatomical variation of the liver, in which the gallbladder is adjacent to the ligamentum teres, that was described until now as "right-sided ligamentum teres and right umbilical portion of the portal vein". A study of eight patients showing this anatomical variation has led to a new archetypal anatomical description of the hepatic and portal veins, using multidetector-row computed tomography (MDCT) with three-dimensional (3D) volume-rendering (VR) reconstructions. While 2D axial imaging gave the same information, MDCT imaging with VR reconstructions provided a clear 3D visualization of this anatomical variation. Typical features can be described as follows: (1) juxtaposition of the ligamentum teres and the gallbladder; (2) typical portal vein branching with a right posterior branch, a left posterior branch and a main medial branch that terminates in the ligamentum teres; (3) two main hepatic veins and a hypotrophied medial hepatic vein. We think, based on the direct comparison of anatomical findings and knowledge of chronological embryological development, that this abnormality results from the defective development of the central part of the liver and not from the persistence of the right rather than the left umbilical vein. Because of the presence of only one medial plane, containing both the gallbladder and the ligamentum teres, we propose renaming it "fusion of hepatic planes"

Binding and Kinetic Analysis of Human Protein Phosphatase PP2A Interactions with Caspase 9 Protein and the Interfering Peptide C9h

International audienceThe serine/threonine phosphatase PP2A and the cysteine protease Caspase 9 are two proteins involved in physiological and pathological processes, including cancer and apoptosis. We previously demonstrated the interaction between Caspase 9 and PP2A and identified the C9h peptide, corresponding to the binding site of Caspase 9 to PP2A. This interfering peptide can modulate Caspase 9/PP2A interaction leading to a strong therapeutic effect in vitro and in vivo in mouse models of tumor progression. In this manuscript, we investigate (I) the peptide binding to PP2A combining docking with molecular dynamics and (II) the secondary structure of the peptide using CD spectroscopy. Additionally, we compare the binding affinity, using biolayer interferometry, of the wild-type protein PP2A with Caspase 9 and vice versa to that observed between the PP2A protein and the interfering peptide C9h. This result strongly encourages the use of peptides as new therapeutics against cancer, as shown for the C9h peptide already in clinical trial

Association of shear-wave elastography with clinical outcomes post-liver transplantation

International audiencePurpose: Two-dimensional shear-wave elastography (2D-SWE) assessment of liver stiffness has the advantage of being obtained during conventional ultrasound. Liver-stiffness values on 2D-SWE for grafted livers are unknown, as are their potential link to post-transplantation morbidity. This study was undertaken to determine liver-stiffness values on 2D-SWE for grafted livers without complications, and examine relationships between liver-stiffness values on 2D-SWE and early post-operative arterial or biliary complications.Methods: In our facility, all liver-transplant recipients are entered in a comprehensive surgical database, where donor, procedure and recipient characteristics are described. All patients underwent systematic 2D-SWE assessment. Potential relationships were analyzed between liver-stiffness findings and donor, procedure and recipient characteristics, and follow-up events, including death, arterial or biliary complications, graft removal and allograft-dysfunction scores.Results: Liver-stiffness values on 2D-SWE of 337 ultrasound examinations from 165 liver-transplant recipients were collected retrospectively. Median time from transplantation to 2D-SWE examination was 149 days, with median follow-up at 36 months. The mean±SD stiffness value for grafts without complications was 7.3±2.3kPa; it was significantly higher during the first 90 days (8.2±2.5kPa) post-transplant than after 1year (7.0±2.4kPa) (P=0.01). Patients with biliary complications during the first-year post-transplantation had significantly higher mean liver-stiffness values on 2D-SWE than those without, respectively: 9.8±7.0 vs 7.5±1.8kPa (P=0.01).Conclusions: Post-transplantation patients without complications had stiffer livers than the general population, with higher values during the first 90 days after surgery. Liver-stiffness values on 2D-SWE were significantly higher for patients with biliary, but not arterial, complications

Cold-to-warm machine perfusion of the liver: a novel circuit for an uninterrupted combined perfusion protocol

International audienceBackground: Ex-vivo perfusion of liver grafts is associated with promising results for the preservation of marginal grafts. Recent studies highlight the need for a combination of perfusion conditions, such as hypothermic followed by normothermic perfusion. While comprehensive machines dedicated to liver perfusion have been developed, these systems remain costly and poorly adaptable to perfusion condition switch, which requires a complete interruption of the perfusion process. Our team aimed at developing an adaptable and simple circuit for uninterrupted ex-vivo liver perfusion.Methods: Together with specialized bioengineers, we developed a highly adaptable circuit that can fit on already pre-existing extracorporeal oxygenation machines routinely used in cardiovascular surgery. This circuit, owing to its reservoir, allows any type of perfusion conditions without interrupting the perfusion process.Results: In a preliminary study, to assess the technical feasibility of liver perfusion using our circuit under different conditions, we performed 7 perfusions of discarded liver grafts. HOPE and DHOPE hypothermic perfusion could be performed, and a switch to normothermia was easily possible within seconds. From there, a dynamic perfusion sequence model was developed.Conclusion: This circuit may represent a simpler alternative or a new refinement to existing perfusion systems allowing uninterrupted combined perfusion protocols