Effect of the NGF receptors overexpression on breast cancer cells growth

Notre laboratoire fut le premier a démontrer l'effet mitogène et antiapoptotique du NGF sur les cellules de cancer du sein de façon autocrine. Cette action du NGF se fait via ses deux récepteurs membranaires : le récepteur à activité tyrosine kinase TrkA, et le récepteur p75NTR appartenant à la superfamille du TNFR. Afin de comprendre le rôle et les mécanismes d'action de ces deux récepteurs dans le cancer du sein, nous avons établi et caractérisé des modèles cellulaires MDA-MB-231 surexprimant TrkA ou p75NTR. Lors de mes travaux de thèse, j'ai montré que la surexpression de TrkA augmente la croissance, la migration et l'invasion des cellules. D'autre part, la surexpression de TrkA augmente la résistance des cellules aux apoptogènes et à l'anoïkis. ln vivo, en souris immunodéficientes SCID, la surexpression de TrkA induit une augmentation de la croissance des tumeurs primaires et de la métastase dans les poumons, le foie et le cerveau. L'augmentation de la croissance tumorale est corrélée à une prolifération des cellules cancéreuses et à une angiogenèse accrue, tandis que la métastase est corrélée avec une augmentation de la résistance à l'anoïkis. La surexpression de p75NTR dans les cellules de cancer du sein entraîne quant à elle un ralentissement important de la croissance cellulaire du à un blocage du cycle en G1. Cependant, la surexpression de p75NTR s'accompagne également d'une survie accrue aux apoptogènes. Nos investigations montrent que ces effets pourtant apparemment contradictoires sont tous deux le fruit d'une augmentation de l'expression de p21waf1 induite par la surexpression de p75NTR. Malgré ces effets apparemment opposés observés in vitro, la surexpression de p75NTR in vivo provoque une augmentation de la croissance des tumeurs primaires. L'ensemble de ces résultats montre que la surexpression de TrkA et celle de p75NTR augmentent l'agressivité des cellules cancéreuses de sein et ouvrent des perspectives encourageantes dans le développement de stratégies thérapeutiques contre le cancer du sein.Our laboratory was the first to demonstrate the mitogen and antiapoptotic effects of NGF on of breast cancer ceIls through an autocrine loop. NGF acts via its two receptors: the receptor tyrosine kinase TrkA and the p75NTR receptor, a member of the TNFRs superfamily. To understand the role and the mechanisms of action of these two receptors in breast cancer, we have established and characterized models of MDA-MB-231 overexpressing TrkA or p75NTR. During my thesis work, 1 showed that the TrkA overexpression increases growth, migration and invasion of cells. On the other hand, the TrkA overexpression increases the resistance of cells to apoptogen and anoikis. ln vivo, in SCID mice, TrkA overexpression causes increased growth of primary tumors and metastasis in the lungs, liver and brain. The increase in tumor growth is correlated to a proliferation of cancer cells and an increased angiogenesis, while the metastasis is correlated with increased resistance to anoikis. The p75NTR overexpression in breast cancer cells causes a significant cell growth decrease due to a celI cycle blockage in G1 phase. However, the p75NTR overexpression also induces increased survival to apoptogen. Our investigations show that these apparently contradictory effects are both the result of an increased expression of p21waf1 induced by p75NTR overexpression. Despite these seemingly opposite effects observed in vitro, the p75NTR overexpression in vivo causes an increased primary tumors growth. AlI these results show that TrkA and p75NTR overexpression increase the aggressiveness of breast cancer celIs and open up prospects in the development of therapeutic strategies against breast cancer

Impact de la surexpression des récepteurs du NGF sur la croissance des cellules de cancer du sein

Notre laboratoire fut le premier a démontrer l'effet mitogène et antiapoptotique du NGF sur les cellules de cancer du sein de façon autocrine. Cette action du NGF se fait via ses deux récepteurs membranaires : le récepteur à activité tyrosine kinase TrkA, et le récepteur p75NTR appartenant à la superfamille du TNFR. Afin de comprendre le rôle et les mécanismes d'action de ces deux récepteurs dans le cancer du sein, nous avons établi et caractérisé des modèles cellulaires MDA-MB-231 surexprimant TrkA ou p75NTR. Lors de mes travaux de thèse, j'ai montré que la surexpression de TrkA augmente la croissance, la migration et l'invasion des cellules. D'autre part, la surexpression de TrkA augmente la résistance des cellules aux apoptogènes et à l'anoïkis. ln vivo, en souris immunodéficientes SCID, la surexpression de TrkA induit une augmentation de la croissance des tumeurs primaires et de la métastase dans les poumons, le foie et le cerveau. L'augmentation de la croissance tumorale est corrélée à une prolifération des cellules cancéreuses et à une angiogenèse accrue, tandis que la métastase est corrélée avec une augmentation de la résistance à l'anoïkis. La surexpression de p75NTR dans les cellules de cancer du sein entraîne quant à elle un ralentissement important de la croissance cellulaire du à un blocage du cycle en G1. Cependant, la surexpression de p75NTR s'accompagne également d'une survie accrue aux apoptogènes. Nos investigations montrent que ces effets pourtant apparemment contradictoires sont tous deux le fruit d'une augmentation de l'expression de p21waf1 induite par la surexpression de p75NTR. Malgré ces effets apparemment opposés observés in vitro, la surexpression de p75NTR in vivo provoque une augmentation de la croissance des tumeurs primaires. L'ensemble de ces résultats montre que la surexpression de TrkA et celle de p75NTR augmentent l'agressivité des cellules cancéreuses de sein et ouvrent des perspectives encourageantes dans le développement de stratégies thérapeutiques contre le cancer du sein.Our laboratory was the first to demonstrate the mitogen and antiapoptotic effects of NGF on of breast cancer ceIls through an autocrine loop. NGF acts via its two receptors: the receptor tyrosine kinase TrkA and the p75NTR receptor, a member of the TNFRs superfamily. To understand the role and the mechanisms of action of these two receptors in breast cancer, we have established and characterized models of MDA-MB-231 overexpressing TrkA or p75NTR. During my thesis work, 1 showed that the TrkA overexpression increases growth, migration and invasion of cells. On the other hand, the TrkA overexpression increases the resistance of cells to apoptogen and anoikis. ln vivo, in SCID mice, TrkA overexpression causes increased growth of primary tumors and metastasis in the lungs, liver and brain. The increase in tumor growth is correlated to a proliferation of cancer cells and an increased angiogenesis, while the metastasis is correlated with increased resistance to anoikis. The p75NTR overexpression in breast cancer cells causes a significant cell growth decrease due to a celI cycle blockage in G1 phase. However, the p75NTR overexpression also induces increased survival to apoptogen. Our investigations show that these apparently contradictory effects are both the result of an increased expression of p21waf1 induced by p75NTR overexpression. Despite these seemingly opposite effects observed in vitro, the p75NTR overexpression in vivo causes an increased primary tumors growth. AlI these results show that TrkA and p75NTR overexpression increase the aggressiveness of breast cancer celIs and open up prospects in the development of therapeutic strategies against breast cancer.LILLE1-Bib. Electronique (590099901) / SudocSudocFranceF

A Bloody Conspiracy— Blood Vessels and Immune Cells in the Tumor Microenvironment

Cancer progression occurs in concomitance with a profound remodeling of the cellular microenvironment. Far from being a mere passive event, the re-orchestration of interactions between the various cell types surrounding tumors highly contributes to the progression of the latter. Tumors notably recruit and stimulate the sprouting of new blood vessels through a process called neo-angiogenesis. Beyond helping the tumor cope with an increased metabolic demand associated with rapid growth, this also controls the metastatic dissemination of cancer cells and the infiltration of immune cells in the tumor microenvironment. To decipher this critical interplay for the clinical progression of tumors, the research community has developed several valuable models in the last decades. This review offers an overview of the various instrumental solutions currently available, including microfluidic chips, co-culture models, and the recent rise of organoids. We highlight the advantages of each technique and the specific questions they can address to better understand the tumor immuno-angiogenic ecosystem. Finally, we discuss this development field’s fundamental and applied perspectives

Enzymatically Activated Glyco-Prodrugs of Doxorubicin Synthesized by a Catalysis-Free Diels−Alder Reaction

International audienc

L’art de la guerre appliqué aux DIPG: Connais ton ennemi

International audiencePediatric brain cancers represent the most frequent solid tumors and the leading cause of cancer-driven mortality in children. Pediatric High Grade Gliomas display a very poor prognosis. Among these, DIPG (Diffuse Intrinsic Pontine Gliomas), localized to the brain stem, cannot benefit from a total exeresis due to this critical location and to their highly infiltrating nature. Radiotherapy remains the standard treatment against these tumors for almost five decades, and attempts to improve the prognosis of patients with chemotherapy or targeted therapies have failed. Thanks to the rise of high throughput sequencing, the knowledge of molecular alterations in pediatric gliomas strongly progressed and allowed to highlight distinct biomolecular entities and to establish more accurate diagnoses. In this review, we summarize this new information and the perspectives that it brings for clinical strategies.Les tumeurs cérébrales pédiatriques représentent la principale cause de mortalité par cancer chez l’enfant. Alors que l’exérèse complète a une valeur pronostique dans certains gliomes de haut grade, les DIPG (diffuse intrinsic pontine gliomas) ne peuvent en bénéficier du fait d’une localisation critique au niveau du tronc cérébral et de leur caractère infiltrant. La radiothérapie demeure le traitement de référence contre ces tumeurs depuis bientôt cinquante ans, et les tentatives pour améliorer le pronostic vital des patients à l’aide de chimiothérapies ou de thérapies ciblées se sont révélées infructueuses. La connaissance des altérations moléculaires dans ces gliomes a fortement progressé cette dernière décennie, grâce aux progrès du séquençage à haut débit. Cela a permis de révéler des entités distinctes au niveau moléculaire et de préciser des diagnostics discriminants. Dans cette revue, nous faisons le point sur ces nouvelles connaissances et les perspectives qu’elles apportent en termes de stratégies cliniques

Enzymatically Activated Glyco-Prodrugs of Doxorubicin Synthesized by a Catalysis-Free Diels–Alder Reaction

International audienceThe severe side effects associated with the use of anthracycline anticancer agents continues to limit their use. Herein we describe the synthesis and preliminary biological evaluation of three enzymatically activatable doxorubicin-oligosaccharide prodrugs. The synthetic protocol allows late stage variation of the carbohydrate and is compatible with the use of disaccharides such as lactose as well as more complex oligosaccharides such as xyloglucan oligomers. The enzymatic release of doxorubicin from the prodrugs by both protease (plasmin) and human carboxylesterases (hCE1 and 2) was demonstrated in vitro and the cytotoxic effect of the prodrugs were assayed on MCF-7 breast cancer cells

Ku86 is important for TrkA overexpression-induced breast cancer cell invasion

International audiencePurpose: We have recently shown that breast tumors express high levels of TrkA compared with normal breast tissues, with TrkA overexpression enhancing breast cancer cell invasion in vitro and metastasis in animal models. In this study, we tried to identify molecules involved in TrkA overexpression-mediated biological effects in breast cancer cellsExperimental design: We used a proteomic-based approach to identify proteins involved in TrkA overexpression-stimulated invasion of MDA-MB-231 breast cancer cells. Proteins from control and TrkA overexpressing cells were separated using a cup-loading two-dimensional electrophoresis system before MALDI and LC-MS/MS mass spectrometry analysisResults Among several putative regulated proteins, Ku86 was found increased in TrkA overexpressing cells. Moreover, Ku86 was co-immunoprecipitated with TrkA, suggesting the interaction of these two proteins in TrkA overexpressing cells. Interestingly, inhibition with small-interfering RNA and neutralizing antibodies showed that Ku86 was required for TrkA-stimulated cell invasionConclusions and clinical relevance. These data allowed the identification of Ku86 as a new player involved in metastasis in breast cancer cells. Our findings suggest that TrkA and its down stream signaling pathways should be regarded as potential new targets for the development of future breast cancer therap

Developing a MEMS Device with Built-in Microfluidics for Biophysical Single Cell Characterization

This study combines the high-throughput capabilities of microfluidics with the sensitive measurements of microelectromechanical systems (MEMS) technology to perform biophysical characterization of circulating cells for diagnostic purposes. The proposed device includes a built-in microchannel that is probed by two opposing tips performing compression and sensing separately. Mechanical displacement of the compressing tip (up to a maximum of 14 µm) and the sensing tip (with a quality factor of 8.9) are provided by two separate comb-drive actuators, and sensing is performed with a capacitive displacement sensor. The device is designed and developed for simultaneous electrical and mechanical measurements. As the device is capable of exchanging the liquid inside the channel, different solutions were tested consecutively. The performance of the device was evaluated by introducing varying concentrations of glucose (from 0.55 mM (0.1%) to 55.5 mM (10%)) and NaCl (from 0.1 mM to 10 mM) solutions in the microchannel and by monitoring changes in the mechanical and electrical properties. Moreover, we demonstrated biological sample handling by capturing single cancer cells. These results show three important capabilities of the proposed device: mechanical measurements, electrical measurements, and biological sample handling. Combined in one device, these features allow for high-throughput multi-parameter characterization of single cells

Evofosfamide Is Effective against Pediatric Aggressive Glioma Cell Lines in Hypoxic Conditions and Potentiates the Effect of Cytotoxic Chemotherapy and Ionizing Radiations

Hypoxia is a hallmark of many solid tumors and is associated with resistance to anticancer treatments. Hypoxia-activated prodrugs (HAPs) were developed to target the hypoxic regions of these tumors. Among 2nd generation HAPs, Evofosfamide (Evo, also known as TH-302) exhibits preclinical and clinical activities against adult glioblastoma. In this study, we evaluated its potential in the field of pediatric neuro-oncology. We assessed the efficacy of Evo in vitro as a single drug, or in combination with SN38, doxorubicin, and etoposide, against three pediatric high-grade glioma (pHGG) and three diffuse intrinsic pontine glioma (DIPG) cell lines under hypoxic conditions. We also investigated radio-sensitizing effects using clonogenic assays. Evo inhibited the growth of all cell lines, mainly under hypoxia. We also highlighted a significant synergism between Evo and doxorubicin, SN38, or etoposide. Finally, Evo radio-sensitized the pHGG cell line tested, both with fractionated and single-dose irradiation schedules. Altogether, we report here the first preclinical proof of evidence about Evofosfamide efficiency against hypoxic pHGG and DIPG cells. Since such tumors are highly hypoxic, and Evo potentiates the effect of ionizing radiation and chemotherapy, it appears as a promising therapeutic strategy for children with brain tumors

Tumor-Infiltrating Lymphocytes (TILs) in Epithelial Ovarian Cancer: Heterogeneity, Prognostic Impact, and Relationship with Immune Checkpoints

Epithelial ovarian cancers (EOC) are often diagnosed at an advanced stage with carcinomatosis and a poor prognosis. First-line treatment is based on a chemotherapy regimen combining a platinum-based drug and a taxane-based drug along with surgery. More than half of the patients will have concern about a recurrence. To improve the outcomes, new therapeutics are needed, and diverse strategies, such as immunotherapy, are currently being tested in EOC. To better understand the global immune contexture in EOC, several studies have been performed to decipher the landscape of tumor-infiltrating lymphocytes (TILs). CD8+ TILs are usually considered effective antitumor immune effectors that immune checkpoint inhibitors can potentially activate to reject tumor cells. To synthesize the knowledge of TILs in EOC, we conducted a review of studies published in MEDLINE or EMBASE in the last 10 years according to the PRISMA guidelines. The description and role of TILs in EOC prognosis are reviewed from the published data. The links between TILs, DNA repair deficiency, and ICs have been studied. Finally, this review describes the role of TILs in future immunotherapy for EOC