References of "Delvenne, Philippe"
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See detailToxic epidermal necrolysis and antifolate drugs in cancer chemotherapy.
Franchimont, Claudine ULg; Lesuisse, Marianne; Humbert, Philippe et al

in Current Drug Safety (2012), 7(5), 357-60

Folates are one-carbon donors essential for synthesizing purines, pyrimidines, serine, and methionine. They correspond to anionic hydrophilic molecules essential for DNA synthesis in mammalian cells. The ... [more ▼]

Folates are one-carbon donors essential for synthesizing purines, pyrimidines, serine, and methionine. They correspond to anionic hydrophilic molecules essential for DNA synthesis in mammalian cells. The latter cells lack the capacity to synthesize folates. In some patients, high dosages of antifolate drugs (eg: methotrexate, pemetrexed) used in cancer chemotherapy alter the keratinocytes, endothelial cells and Factor XIIIa+ dermal dendrocytes in a range of various severities. Such conditions clinically designed under the heading antifolate cytotoxic skin reaction (ACSR) occasionally resemble the toxic epidermal necrolysis (TEN) / Stevens-Johnson syndrome (SJS) spectrum. Whether or not the TEN/SJS presentation of ACSR is a regular condition similar to that induced by other drugs or a variant condition supported by a unique pathomechanism is unsettled. [less ▲]

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See detailLe melanome cutane: une seule maladie?
PIERARD, Gérald ULg; Franchimont, Claudine ULg; Hermanns-Le, Trinh ULg et al

in Revue Médicale de Liège (2012), 67(9), 458-60

For the media and the public at large, malignant melanoma is the most dreadful cancer of the skin. This statement is obvious. However, some nuances merit to be considered. The clinical presentations ... [more ▼]

For the media and the public at large, malignant melanoma is the most dreadful cancer of the skin. This statement is obvious. However, some nuances merit to be considered. The clinical presentations, histopathology and molecular genetics point to the fact that malignant melanoma is not a single monolithic pathological condition. Different types of melanomas are distinguished based on distinct origins and contrasted prognoses. The management and information for the patient should be handled individually. [less ▲]

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See detailHuman papillomavirus DNA strongly correlates with a poorer prognosis in oral cavity carcinoma.
Duray, A; Descamps, G; Decaestecker, C et al

in Laryngoscope (2012), 122(7), 1558-65

OBJECTIVES/HYPOTHESIS: The prevalence of human papillomavirus (HPV) in a clinical series of 162 patients with oral squamous cell carcinoma (OSCC) was studied. Furthermore, we analyzed the correlation ... [more ▼]

OBJECTIVES/HYPOTHESIS: The prevalence of human papillomavirus (HPV) in a clinical series of 162 patients with oral squamous cell carcinoma (OSCC) was studied. Furthermore, we analyzed the correlation between the immunohistochemical expression of p16, p53, epidermal growth factor receptor (EGFR), and HPV status to predict survival in OSCC patients. STUDY DESIGN: Retrospective study. METHODS: Paraffin-embedded samples from OSCC patients (n = 162) were evaluated for the presence of HPV DNA using both GP5+/GP6+ consensus polymerase chain reaction (PCR) and type-specific E6/E7 PCR to detect HPV types 6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 67, and 68. Immunohistochemical staining for p16, p53, and EGFR was also performed. RESULTS: The type-specific E6/E7 PCR demonstrated that 65 of the 147 OSCC patients (44%) presented with high-risk (hr) HPV types and that 38 of the 147 OSCC patients (26%) presented with low-risk (lr) HPV types. Comparable p53 and EGFR expression levels were observed in the hr HPV+ group (41.5% p53+, 92% EGFR+) and the lr HPV+ group (57% p53+, 92% EGFR+). Conversely, a slight increase in the proportion of p16+ tumors was observed in the hr HPV+ group (65%) compared with the lr HPV+ group (44%). In regard to patient outcome, the presence of HPV was correlated with a worse prognosis (P = .007). CONCLUSIONS: A high prevalence of hr and lr HPV infections was detected in the OSCC patients included in the study. Moreover, hr HPV positivity was correlated with a decreased 5-year disease-free survival rate compared with HPV- and lr HPV+. [less ▲]

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See detailOccurrence of cardiovascular calcifications in normal, aging rats.
Roosens, B; Bala, G; Droogmans, S et al

in Experimental Gerontology (2012), 47(8), 614-9

BACKGROUND: Cardiovascular calcification is an independent predictor of morbidity and mortality and increases with age. Animal models are frequently used to investigate the underlying pathophysiology ... [more ▼]

BACKGROUND: Cardiovascular calcification is an independent predictor of morbidity and mortality and increases with age. Animal models are frequently used to investigate the underlying pathophysiology. Only scarce data regarding the effect of aging on calcifications in these animal models are available. The aim of this study is to investigate the occurrence of cardiovascular calcifications in normal, aging rats. METHODS: A mixed inbred/outbred population of 44 male Lewis/Wistar rats was studied. Group 1 of three-month-old rats, group 2 twelve-month-old, group 3 twenty-four-month-old and group 4 thirty-month-old rats. Calibrated integrated backscatter (cIB) values and blood parameters (creatinine, parathyroid hormone (PTH)) were measured, followed by ex-vivo micro-CT and histology as reference methods. RESULTS: Cardiovascular calcifications developed with age, as demonstrated by significantly increasing cIB values of the aortic valve and myocardium. This was confirmed by a significant increase in the calcified volume on ex-vivo micro-CT and in the histological calcium score. There was also a significantly higher level of creatinine and PTH with age. CONCLUSIONS: As in humans, cardiovascular calcifications progressively increase with age in the normal rat. Therefore the aging rat model could be used for studying calcifying cardiovascular disease. cIB might have a value in future studies for the early detection of subclinical calcifications in humans. [less ▲]

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See detailProinflammatory Cytokines Induce Bronchial Hyperplasia and Squamous Metaplasia in Smokers: Implications for chronic obstructive pulmonary disease therapy.
Herfs, Michael ULg; Hubert, Pascale ULg; POIRRIER, Anne-Lise ULg et al

in American Journal of Respiratory Cell and Molecular Biology (2012), 47(1), 67-79

Tracheobronchial squamous metaplasia is common in smokers and is associated with both airway obstruction in chronic obstructive pulmonary disease (COPD) and increased risk of lung cancer. Whereas this ... [more ▼]

Tracheobronchial squamous metaplasia is common in smokers and is associated with both airway obstruction in chronic obstructive pulmonary disease (COPD) and increased risk of lung cancer. Whereas this reversible epithelial replacement is almost always observed in association with chronic inflammation, the role of inflammatory mediators in the pathogenesis of squamous metaplasia is still unclear. In the present study, we investigated the implication of cigarette smoke-mediated pro-inflammatory cytokine up-regulation in the development and treatment of tracheobronchial epithelial hyperplasia and squamous metaplasia. By using immunohistological techniques, we showed a higher epithelial expression of TNFalpha, IL-1beta and IL-6 as well as an activation of NF-kappaB and AP-1/MAPK signalling pathways in the respiratory tract of smoking patients compared to the normal ciliated epithelium of non-smoking patients. In addition, we demonstrated that these signalling pathways strongly influence the proliferation and the differentiation state of in vitro generated normal human airway epithelial basal cells. Finally, we exposed mice to cigarette smoke for 16 weeks and demonstrated that anti-TNFalpha (etanercept), anti-IL-1beta (anakinra) and/or anti-IL-6R (tocilizumab) therapies significantly reduced epithelial hyperplasia and squamous metaplasia development. These data highlight the importance of soluble inflammatory mediators in the pathogenesis of tracheobronchial squamous metaplasia. Therefore, administration of pro-inflammatory cytokine antagonists may have clinical application in the management of COPD patients. [less ▲]

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See detailDermal ultrastructure in low Beighton score members of 17 families with hypermobile-type Ehlers-Danlos syndrome.
Hermanns-Le, Trinh ULg; REGINSTER, Marie-Annick ULg; Franchimont, Claudine ULg et al

in Journal of Biomedicine & Biotechnology (2012), 2012

The distinction between the Ehlers-Danlos syndrome hypermobile type (EDSH) and the benign joint hypermobility syndrome (BJHS) is unclear. The aim of the present study was to compare skin ultrastructural ... [more ▼]

The distinction between the Ehlers-Danlos syndrome hypermobile type (EDSH) and the benign joint hypermobility syndrome (BJHS) is unclear. The aim of the present study was to compare skin ultrastructural abnormalities of EDSH and BJHS among different families. Skin of 23 EDSH, 27 BJHS, and 41 asymptomatic subjects from 17 families was examined using transmission electron microscopy. Similar ultrastructural abnormalities were found irrespective of the Beighton score. Flower-like collagen fibrils represented the key change and elastic fibers were altered as well. Beighton score is a clinical parameter rating joint mobility that appeared unrelated to quantitative and qualitative collagen ultrastructural alterations in the skin. Some EDSH family members fit with BJHS diagnosis. BJHS possibly represents a mild variant of EDSH. [less ▲]

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See detailMiconazole , a pharmacological barrier to skin fungal infections.
Pierard, Gérald ULg; Hermanns-Le, Trinh ULg; Delvenne, Philippe ULg et al

in Expert Opinion on Pharmacotherapy (2012), 13(8), 1187-94

Introduction: Miconazole (MCZ) is a time-honored antifungal of the imidazole class. MCZ exerts a multipronged effect on fungi. It inhibits the cytochrome P450 complex, including the 14alpha-demethylase ... [more ▼]

Introduction: Miconazole (MCZ) is a time-honored antifungal of the imidazole class. MCZ exerts a multipronged effect on fungi. It inhibits the cytochrome P450 complex, including the 14alpha-demethylase enzyme required for ergosterol biosynthesis, in fungal cell membranes. In addition, intracellular accumulation of toxic methylated sterols occurs and the synthesis of triglycerides and phospholipids is altered. Disturbances in oxidative and peroxidative enzyme activities lead to an intracellular toxic concentration of hydrogen peroxide. As a result, intracellular organelle destruction then leads to cell necrosis. Farnesol synthesis stimulated in Candida spp. prevents the yeast-to-mycelium formation. MCZ is further active against Gram-positive bacteria. Areas covered: This review aims at revisiting the MCZ antifungal activity in dermatomycoses. Expert opinion: MCZ's wide spectrum of activity appears noteworthy. The full pharmacological profile of MCZ indicates its fungistatic profile through its effect on ergosterol biosynthesis. In addition, it exhibits a fungicidal effect against a number of fungal species, due to hydrogen peroxide accumulation. MCZ is characterized by high safety, efficacy and versatility, and a unique, multifaceted nature of activity in the treatment of dermatomycoses. [less ▲]

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See detailUstekinumab in psoriasis immunopathology with emphasis on the Th17-IL23 axis. A primer.
QUATRESOOZ, Pascale ULg; Hermanns-Le, Trinh ULg; Pierard, Gérald ULg et al

in Journal of Biomedicine & Biotechnology (2012), 2012(147413),

Psoriasis is a chronic relapsing immunoinflammatory dermatosis that is commonly associated with systemic comorbidities. The pathogenic importance of interleukin (IL)-12 and IL-23 is beyond doubt, as well ... [more ▼]

Psoriasis is a chronic relapsing immunoinflammatory dermatosis that is commonly associated with systemic comorbidities. The pathogenic importance of interleukin (IL)-12 and IL-23 is beyond doubt, as well as the involvement of T helper cells (Th)1 and Th17 cells. There is upregulation of the p40 subunit shared by IL-12 and IL-23 and of the IL-23 p19 subunit, but not an increased expression of the IL-12 p35 subunit. This indicates that IL-23 appears more involved than IL-12 in the pathogenesis of psoriatic plaques. Ustekinumab is a fully human monoclonal antibody of the immunoglobulin (Ig) G1 class targeting the p40 subunit common to both IL-12 and IL-23, thus inhibiting both IL-12 and IL-23 receptor-mediated signalling. Ustekinumab is part of the recent biologic therapies active in psoriasis, autoimmune arthritides, and inflammatory bowel diseases. [less ▲]

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See detailMalignant melanoma and its stromal nonimmune microecosystem.
PIERARD, Gérald ULg; Franchimont, Claudine ULg; Delvenne, Philippe ULg

in Journal of Oncology (2012), 2012

In recent years, rapid advances were reached in the understanding of a series of biologic signals influencing cutaneous malignant melanoma (CMM) cells. CMM is in close contact with a peculiar dermal ... [more ▼]

In recent years, rapid advances were reached in the understanding of a series of biologic signals influencing cutaneous malignant melanoma (CMM) cells. CMM is in close contact with a peculiar dermal extracellular matrix (ECM). Stromal cells store and release various structural ECM components. The impact on CMM growth and progression is mediated through strong and long-lasting effects of ECM products. This paper summarizes some peculiar aspects of the peri-CMM stroma showing intracytoplasmic loads in Factor XIIIa, CD34, versican, and alpha (IV) collagen chains. The restricted peri-CMM skin territory exhibiting such changes corresponds to the area showing neoangiogenesis and extravascular unicellular metastatic spread. The latter inconspicuous migratory CMM cells possibly correspond to CMM stem cells or to CMM cells with aberrant HOX gene expression. Their presence is associated with an increased risk for metastases in the regional sentinel lymph nodes. In conclusion, the CMM-stroma connection appears crucial to the growth regulation, invasiveness and initial metastatic spread of CMM cells. Although much remains to be learned in this field, the active intervention of the peri-CMM stroma is likely involved in the inconspicuous early metastatic migration of CMM cells. [less ▲]

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See detailOverexpression of GRP94 in breast cancer cells resistant to oxidative stress promotes high levels of cancer cell proliferation and migration: implications for tumor recurrence.
Dejeans, Nicolas; Glorieux, Christophe; Guénin, Samuel ULg et al

in Free Radical Biology & Medicine (2012), 52(6), 993-1002

Targeting the altered redox status of cancer cells is emerging as an interesting approach to potentiate chemotherapy. However, to maximize the effectiveness of this strategy and define the correct ... [more ▼]

Targeting the altered redox status of cancer cells is emerging as an interesting approach to potentiate chemotherapy. However, to maximize the effectiveness of this strategy and define the correct chemotherapeutic associations, it is important to understand the biological consequences of chronically exposing cancer cells to reactive oxygen species (ROS). Using an H(2)O(2)-generating system, we selected a ROS-resistant MCF-7 breast cancer cell line, namely Resox cells. By exploring different survival pathways that are usually induced during oxidative stress, we identified a constitutive overexpression of the endoplasmic reticulum chaperone, GRP94, in these cells, whereas levels of its cytoplasmic homolog HSP90, or GRP78, were not modified. This overexpression was not mediated by constitutive unfolded protein response (UPR) activation. The increase in GRP94 is tightly linked to an increase in cell proliferation and migration capacities, as shown by GRP94-silencing experiments. Interestingly, we also observed that GRP94 silencing inhibits migration and proliferation of the highly aggressive MDA-MB-231 cells. By immunohistochemistry, we showed that GRP94 expression was higher in recurrent human breast cancers than in their paired primary neoplasias. Similar to the situation in the Resox cells, this increase was not associated with an increase in UPR activation in recurrent tumors. In conclusion, this study suggests that GRP94 overexpression may be a hallmark of aggressiveness and recurrence in breast cancers. [less ▲]

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See detailAberrant promoter methylation and expression of UTF1 during cervical carcinogenesis.
Guenin, Samuel; Mouallif, Mustapha ULg; Deplus, Rachel et al

in PLoS ONE (2012), 7(8), 42704

Promoter methylation profiles are proposed as potential prognosis and/or diagnosis biomarkers in cervical cancer. Up to now, little is known about the promoter methylation profile and expression pattern ... [more ▼]

Promoter methylation profiles are proposed as potential prognosis and/or diagnosis biomarkers in cervical cancer. Up to now, little is known about the promoter methylation profile and expression pattern of stem cell (SC) markers during tumor development. In this study, we were interested to identify SC genes methylation profiles during cervical carcinogenesis. A genome-wide promoter methylation screening revealed a strong hypermethylation of Undifferentiated cell Transcription Factor 1 (UTF1) promoter in cervical cancer in comparison with normal ectocervix. By direct bisulfite pyrosequencing of DNA isolated from liquid-based cytological samples, we showed that UTF1 promoter methylation increases with lesion severity, the highest level of methylation being found in carcinoma. This hypermethylation was associated with increased UTF1 mRNA and protein expression. By using quantitative RT-PCR and Western Blot, we showed that both UTF1 mRNA and protein are present in epithelial cancer cell lines, even in the absence of its two main described regulators Oct4A and Sox2. Moreover, by immunofluorescence, we confirmed the nuclear localisation of UTF1 in cell lines. Surprisingly, direct bisulfite pyrosequencing revealed that the inhibition of DNA methyltransferase by 5-aza-2'-deoxycytidine was associated with decreased UTF1 gene methylation and expression in two cervical cancer cell lines of the four tested. These findings strongly suggest that UTF1 promoter methylation profile might be a useful biomarker for cervical cancer diagnosis and raise the questions of its role during epithelial carcinogenesis and of the mechanisms regulating its expression. [less ▲]

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See detailHuman papillomavirus, lichen sclerosus and penile cancer: A study in Belgium.
D'Hauwers, K. W. M.; Depuydt, C. E.; Bogers, J. J. et al

in Vaccine (2012), 30(46), 6573-7

PURPOSE: The prevalence of penile cancer varies between 1.5 (industrialized countries) and 4.5 per 100,000 men (non-industrialized countries). Predominant histological subtype is squamous cell carcinoma ... [more ▼]

PURPOSE: The prevalence of penile cancer varies between 1.5 (industrialized countries) and 4.5 per 100,000 men (non-industrialized countries). Predominant histological subtype is squamous cell carcinoma (SCC). Human papillomavirus (HPV) is found in 40-46% of cases: penile cancer is considered to behave as vulvar cancer. Non HPV related risk factors are lack of circumcision, phimosis, chronic inflammation, and smoking. The role of lichen sclerosus (LS) is unclear. Clinical diagnosis is difficult and treatment often mutilating. Preventive measures can be taken since the risk factors are known: the use of the prophylactic HPV vaccines may contribute. We measured the prevalence of HPV and LS in penile cancer in Belgium. MATERIALS AND METHODS: We found 76 samples of penile lesions in the archives of the departments of Histology of four university hospitals in Belgium. Real-time PCR of type-specific HPV DNA was performed targeting 18 HPV types. PRINCIPAL RESULTS: Patients with penile intraepithelial neoplasia (PeIN) were 56.1 years of age: patients with invasive penile cancer (IPC) 68.5 (p=0.009). Fifty-five samples (55/76) were adequate for HPV targeting. Overall HPV DNA was 70.9%: 89.5% in samples of PeIN (n=19) and 61.1% in samples of IPC (n=36). Invasive penile cancer samples were less likely to be HPV infected (p=0.028). HPV 16 was most prevalent: 48.3%: 20% PeIN, and 28.3% IPC. HPV DNA of the types, included in the prophylactic vaccines, was found in 33% of PeIN and 31.7% of IPC samples. Thrice, low risk HPV (lrHPV) types 6 (1 IPC) and 11 (1 PeIN, 1 IPC) were solely present. There was no difference in the presence of LS between HPV positive and HPV negative samples (p=0.944). CONCLUSIONS: Prevalence of HPV DNA in penile lesions in Belgium is high. However, the prophylactic vaccines may contribute to primary prevention of only a subset of cases. The role of LS remains unclear. [less ▲]

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See detailDetection and quantification of human papillomavirus in benign and malignant parotid lesions.
Descamps, Geraldine; Duray, Anaelle; Rodriguez, Alexandra et al

in Anticancer Research (2012), 32(9), 3929-32

Background/Aim: Human papillomavirus (HPV) is implicated in head and neck squamous cell carcinomas. However, the causal role of HPV in carcinomas of the parotid gland remains uncertain and less documented ... [more ▼]

Background/Aim: Human papillomavirus (HPV) is implicated in head and neck squamous cell carcinomas. However, the causal role of HPV in carcinomas of the parotid gland remains uncertain and less documented. This study aimed to determine the potential implication of HPV in the development of benign and malignant lesions of the parotid gland. MATERIALS AND METHODS: Paraffin-embedded biopsies were obtained from 40 patients with benign parotid gland tumors and from 39 patients with parotid gland carcinomas. The 79 samples were evaluated for the presence of HPV DNA using both GP5+/GP6+ consensus Polymerase Chain Reaction (PCR) and type-specific E6/E7 PCR to detect 18 HPV types. RESULTS: Our results showed a low prevalence of HPV, with only three HPV-positive cases among the 40 benign tumors and one infected carcinoma in the malignant population. CONCLUSION: No association between the presence of HPV DNA and the development of parotid gland tumors was found in our study. [less ▲]

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See detailLes cancers viro-induits: interrelations genetique-environnement
Delvenne, Philippe ULg; Renoux, V. M.; Arafa, M. et al

in Revue Médicale de Liège (2012), 67(5-6), 381-9

Among cancers diagnosed worldwide on a yearly basis, 20% are thought to be associated with a viral infection. The viruses involved are, by order of decreasing incidence, the hepatitis viruses, the ... [more ▼]

Among cancers diagnosed worldwide on a yearly basis, 20% are thought to be associated with a viral infection. The viruses involved are, by order of decreasing incidence, the hepatitis viruses, the papillomaviruses and the Epstein-Barr virus. These virus-induced cancers generate a high level of interest not only for the study of mechanisms involved in the neoplastic transformation, but also for the set-up of specific immunotherapies including prophylactic and therapeutic antitumor vaccination. [less ▲]

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See detailIs an alcoholic fixative fluid used for manual liquid-based cytology accurate to perform HPV tests?
Garbar, Christian; Mascaux, Corinne; De Graeve, Philippe et al

in Pathology and Laboratory Medicine International (2012), 4

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See detailThérapie du mésothéliome pleural : compréhension des mécanismes de résistance à la chimiothérapie
Costa, Chrisostome ULg; Vandermeers, Fabian ULg; Reddy, NS Sathyanarayana ULg et al

Diverse speeche and writing (2011)

Thérapie du mésothéliome pleural : compréhension des mécanismes de résistance à la chimiothérapie. Chrisostome Costa 1, Fabian Vandermeers 2, Sathyanarayana Reddy 2, Céline Mascaux 3, Pascale Hubert 2 ... [more ▼]

Thérapie du mésothéliome pleural : compréhension des mécanismes de résistance à la chimiothérapie. Chrisostome Costa 1, Fabian Vandermeers 2, Sathyanarayana Reddy 2, Céline Mascaux 3, Pascale Hubert 2, Philippe Delvenne 2, Luc Willems 1,2 1 Laboratoire de biologie cellulaire et moléculaire, ULg, Gemboux Agro Bio-Tech, 13 av. Maréchal Juin, 5030 Gembloux ; Tél. : 32-(0)-81-622157 ; Fax : 32-(0)-81-6138 88 ; Courriel: ccosta@doct.ulg.ac.be 2 GIGA, ULg, Liège 3 Institut Bordet, ULB, Bruxelles - Introduction : Le mésothéliome pleural malin (MPM) est un cancer de la plèvre causé principalement par l’inhalation de fibres d’amiante. Nous avons montré précédemment que les inhibiteurs d’histones deacetylases (tel que le valproate, VPA) augmentent significativement l’efficacité des composés utilisés en chimiothérapie (pemetrexed et cisplatin) et prolonge la survie des patients atteints de MPM. Malheureusement, une proportion importante des patients développe une résistance au traitement de seconde ligne avec la doxorubicine et le VPA. - But du projet : L’objectif du travail est de disséquer les mécanismes qui régissent la réponse au traitement de seconde ligne du MPM. - Méthodes et résultats : Nous avons tout d’abord comparé deux types de lignées cellulaires présentant soit une sensibilité (cellules M14K) soit une résistance (cellules H28) au traitement combiné VPA+doxorubicine. En utilisant des microdamiers (Agilent), nous avons analysé le profil d’expression génique de cellules M14K et H28 traitées avec le VPA et la doxorubicine. Après quantification des fluorescences, une analyse statistique (Genespring GX) et une modélisation bioinformatique (Ingenuity) ont permis d’identifier les gènes candidats les plus relevants. En fonction de la p-value et du fold change, un nombre limité de gènes ont été sélectionnés et validés par la technique de qRT-PCR. Parmi ceux-ci, nous avons identifié le gène TGFA dont l’expression corrèle avec la résistance au traitement. En effet, nous avons observé que le niveau d’expression basale du gène TGFA est beaucoup plus important dans la lignée résistante H28 que dans la lignée sensible M14K. Dans le but de valider son implication dans la réponse à la thérapie, nous avons diminué (par interférence ARN) ou augmenté (par transfection d’un vecteur d’expression) l’expression de TGFA respectivement dans les lignées H28 ou M14K. Nous avons ensuite déterminé les taux d’apoptose en évaluant la fragmentation de l’ADN en présence de doxorubicine et de VPA. Les résultats montrent que la diminution de l’expression de TGFA permet une augmentation sensible de l’apoptose induite par le traitement combiné doxorubicine et VPA dans la lignée résistante H28 (de 9% à 36%). A l’inverse, la surexpression de TGFA est associée avec une diminution d’apoptose dans la lignée sensible M14K (de 28% à 18%). Ces observations ont été confirmées par une analyse de l’activité des caspases 3 et 7. En accord avec la propriété de la protéine TGFAd’induire la prolifération cellulaire via le récepteur à l’EGF, des inhibiteurs de l’activité tyrosine kinase (l’Iressa et le Tarceva) augmentent l’apoptose induite par la doxorubicine et le VPA dans la lignée résistante H28 (de 16% à 40%). L’efficacité du traitement combiné VPA+doxorubicine+Iressa/Tarceva est actuellement évaluée en modèle murin (souris SCID). - Conclusions : Nous avons identifié un gène, le TGFA, dont l’expression corrèle avec la résistance à l’apoptose induite par la doxorubicine et le VPA. L’utilisation d’inhibiteurs du récepteur EGF pourrait donc améliorer le traitement de seconde ligne du MPM. [less ▲]

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