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Netrin-1, a secreted molecule that was first described for its role in guidance during embryogenesis, was then brought to light for its overexpression in a large number of aggressive cancers. Netrin-1 is a ligand of "dependence receptors". In adults, the interaction between Netrine-1 and these receptors triggers the survival, proliferation, and migration of different cell types. This will confer better survival properties to tumor cells, making them more prone to form aggressive tumors. A recently developed novel therapy aims at inhibiting the binding of Netrin-1 to these receptors in order to trigger cell death by apoptosis. This article presents a review of the functional characteristics of the Netrin-1 molecule, and the potential effects of a novel targeted therapy against Netrin-1 that could lead to very promising results in combination with conventional anti-cancer treatments.La nétrine-1, une nouvelle cible antitumorale.La nétrine-1, une molécule sécrétée mise en évidence pour son rôle de guidage au cours de l’embryogenèse, a été également décrite pour être surexprimée dans de nombreux cancers agressifs. Elle est le ligand de récepteurs dits « à dépendance », à l’origine, chez l’adulte, de la survie, de la prolifération et de la migration de différents types cellulaires, ce qui confère aux cellules cancéreuses des propriétés avantageuses leur permettant de se développer sous forme de tumeurs agressives. Une stratégie thérapeutique consiste à inhiber l’interaction de la nétrine-1 avec son récepteur, ce qui déclenche la mort des cellules par apoptose. Cet article présente une revue des caractéristiques fonctionnelles de cette molécule et les effets potentiels d’une nouvelle thérapie ciblée sur la nétrine-1, dont la combinaison avec les traitements conventionnels pourrait être des plus prometteurs.

Although some genetic alterations in glioblastoma (GBM) have been characterized, the prognostic value of these gene mutations is not yet established in patients treated with standard therapy.40 patients with newly diagnosed GBM, treated between July 2017 and December 2019, and who had genomic analysis were analyzed. Next-generation sequencing techniques (NGS) were used with a panel of 26 genes. Patients were grouped according to MGMT status, the presence or absence of at least one mutated gene on the panel, and p53 expression by immunohistochemistry.the median follow-up was 11.5 months (1.0-37). For all patients, the median duration of progression-free survival was 8 months (95% CI, 5.3-10.7) and the median overall survival (OS) was 17 months (95% CI, 7.5-26.5). Progression-free and overall survival were significantly different according to MGMT status but not according to NGS and p53 status. Three groups of patients according to different combined status could be distinguished due to significant differences in overall survival.we have shown that the presence of MGMT promoter methylation is a good prognostic factor. By grouping the patients according to their MGMT, NGS and p53 status, three groups of patients could be separated according to their overall survival. However, these results must be confirmed on a larger number of patients.

mTORC1 is a central player in cell growth, a process that is tightly regulated by the availability of nutrients and that controls various aspects of metabolism in the normal cell and in severe diseases such as cancers. mTORC1 is a large multiprotein complex, composed of the kinase subunit mTOR, of Ragulator, which attaches mTOR to the lysosome membrane, of the atypical Rag GTPases and the small GTPase RheB, whose nucleotide states directly dictate its localization to the lysosome and its kinase activity, and of RAPTOR, an adaptor that assembles the complex. The activity of the Rag GTPases is further controlled by the GATOR1 and folliculin complexes, which regulate their GTP/GDP conversion. Here, we review recent structures of important components of the mTORC1 machinery, determined by cryo-electron microscopy for the most part, which allow to reconstitute the architecture of active mTORC1 at near atomic resolution. Notably, we discuss how these structures shed new light on the roles of Rag GTPases and their regulators in mTORC1 regulation, and the perspectives that they open towards understanding the inner workings of mTORC1 on the lysosomal membrane.Une moisson de nouvelles structures de mTORC1 - Coup de projecteur sur les GTPases Rag.mTORC1 est un acteur central de la croissance cellulaire, un processus étroitement régulé par la disponibilité de nutriments et qui contrôle diverses étapes du métabolisme dans la cellule normale et au cours de maladies, comme les cancers. mTORC1 est un complexe multiprotéique de grande taille constitué de nombreuses sous-unités, parmi lesquelles deux types de GTPases, Rag et RheB, contrôlent directement sa localisation membranaire et son activité kinase. Dans cette revue, nous faisons le point sur une moisson de structures récentes, déterminées pour la plupart par cryo-microscopie électronique, qui sont en passe de reconstituer le puzzle de l’architecture de mTORC1. Nous discutons ce que ces structures révèlent sur le rôle des GTPases, et ce que leur connaissance ouvre comme perspectives pour comprendre comment mTORC1 fonctionne à la membrane du lysosome.

Adenomatoid tumors are benign tumors from mesothelial origin, usually occurring in the genital tract. Extragenital locations, especially in the adrenal gland are extremely rare. Here we are reporting two cases of a 28-year-old and 50-year-old men with an adenomatoid tumor of the right adrenal gland. Usual morphological aspects join scattered and microcystic pattern with epithelioid or signet-ring cells. According to the morphological features, main differential diagnoses are adenocarcinoma metastasis, vascular tumors or mesotheliomas. Immunohistochemistry provides precious help to confirm the mesothelial origin thanks to positivity of epithelial markers (CK7, AE1-AE3, CK5/6) coupled to mesothelial markers (D2-40, Calretinin, WT1). On the other hand, there is no loss of BAP1 by immunohistochemistry and usually a surexpression of P16. Adrenal gland adenomatoid tumor is a benign tumor, which can be promoted by iatrogenous or constitutive immunodepression.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder that affects different organs and caused by loss-of-function mutations in one of two genes: TSC1 or TSC2. TSC1 or TSC2 gene mutation lead to dysfunction of hamartin or tuberin, respectively. Hamartin and tuberin form a protein complex that helps regulate cellular proliferation. These proteins form a complex that constitutively inhibits the mammalian target of rapamycin (mTOR) signaling pathway, leading to permanent activation of mTOR signaling within all TSC-associated lesions. Major features of TSC include tumors of the brain, skin, heart, lungs and kidneys, seizures and TSC-associated neuropsychiatric disorders, which can include autism spectrum disorder and cognitive disability. These disorders are usually diagnosed in children and adults. Specific guidelines for diagnosis, surveillance, and management have been proposed by the International Tuberous Sclerosis Complex Consensus Group. Several randomized controlled trials led to regulatory approval of the use of mTOR inhibitors for the treatment of renal angiomyolipomas, brain subependymal giant cell astrocytomas, refractory epilepsy and pulmonary lymphangioleiomyomatosis.

Uveal melanoma is a rare cancer in adults, whose highly stereotyped oncogenic events have been decrypted over the last decade. Its epidemiological, genetic and transcriptional features make it a remarkable model of oncogenesis. Malignant transformation involves almost mutually exclusive alteration of fundamental biologic pathways, including chromatin regulation with inactivation of BAP1, splicing with mutations of SF3B1 or translation with mutations of EIF1AX. Uveal melanoma analyses unraveled the splicing defect due to SF3B1 mutations. Understanding the link between these alterations and malignant transformation will be a key step to define novel therapeutic targets.

Tuberous sclerosis is an autosomal dominant genetic disorder that is characterized by epilepsy, mental retardation and facial angiofibromas. Usually, the disease is diagnosed in childhood but there are frustrates form of tuberous sclerosis with or without genetic mutation. This clinical case about a man who is diagnosed a colonic polyposis, a rectal adenocarcinoma and a tuberous sclerosis.La sclérose tubéreuse de Bourneville (STB) est une maladie génétique autosomique dominante qui se manifeste principalement par la triade épilepsie, retard mental et angiofibromes faciaux. Généralement, elle est diagnostiquée dans l’enfance, mais il existe des formes cliniques frustres avec ou sans mutations génétiques. La recherche d’autres manifestations cliniques peut aider au diagnostic notamment l’atteinte intestinale. Notre cas clinique rapporte la découverte d’une polypose intestinale et d’un cancer du rectum chez un patient méconnu de sa maladie génétique. L’intérêt est de voir, à partir de la littérature, la fréquence de la polypose colique ainsi que du cancer colorectal dans la STB et de se poser la question d’un dépistage systématique dans cette population.

Malignant mesothelioma is a rare tumour, usually the result of asbestos exposure. Several cases of familial aggregation have been reported and recently shown to be associated with constitutional mutations of the BAP1 gene. BAP1 is a deubiquitinating enzyme implicated in several different cellular mechanisms such as the repair or differentiation of DNA. About a half of malignant mesotheliomas present a somatic, bi-allelic inactivation of BAP1, demonstrated by nuclear extinction on histochemistry. Constitutional alterations of BAP1 are extremely rare. Present in the heterozygous state they are transmitted as an autosomal dominant. They are associated with a risk of developing other tumours such as uveal and cutaneous melanomas, benign melanocytic tumours (melanocytic BAP1-mutated atypical intradermal tumour or MBAITS) and clear cell renal carcinomas. The causal link between mesothelioma and germinal mutations of BAP1 has still not been clearly identified. At present there is, in France, no consensus on recommendations for the management of patients with these mutations. This article is a synthesis of the literature on the functions of the BAP1 gene, the tumour risks related to its alteration and the follow up of patients bearing a constitutional mutation.

International audience; INTRODUCTION: Diffuse malignant mesothelioma (MMD) is a rare disease. The diagnosis is difficult and needs an antibody panel. The tumor suppressor gene BRCA1 associated protein 1 (BAP1) is involved in several cancers, including MMD. Loss of BAP1 expression is correlated with BAP1 somatic or constitutional genetic defects. Our work assesses the value of integrating BAP1 in the panel of antibodies used for the diagnosis of MMD. MATERIALS AND METHODS: Immunohistochemical techniques were performed on cytological and histological specimens of MMD and adenocarcinoma pleural metastasis. RESULTS: Of the 26 patients with MMD and the 24 patients with adenocarcinoma pleural metastasis, loss of BAP1 expression was observed in 11 (48%) and one adenocarcinoma (6%) on cytological specimens and in 12 MMD (48%) and in one adenocarcinoma (5%) on biopsy specimens. The concordance between immunocytochemistry and immunohistochemistry was 100%. The specificity of BAP1 was 100% on cytological and biopsy specimen for the diagnosis of malignancy in case of mesothelial proliferation. DISCUSSION AND CONCLUSION: Loss of BAP1 expression is an indicator of MMD in a context of mesothelial proliferation. This immunohistochemistry could be integrated in the panel of immunostaining used for MMD diagnosis, either on histological or cytological samples. Furthermore, loss of BAP1 expression guides the patient to an oncology genetic counseling in order to eliminate a MMD developed as part of a constitutional genetic defect

The diagnosis of large cell carcinoma can only be made on a sampled resected tumor and should not be applied to biopsies or cytology. In the 2015 WHO classification, the definition of large cell carcinoma is restricted to carcinomas both lacking morphological signs of glandular, squamous or neuroendocrine differentiation and exhibiting a null or unclear phenotype (TTF1-/p40 ou p63 ou CK5/6+ focally). These carcinomas have an adenocarcinoma molecular profile because they harbor a significant number of KRAS and BRAF mutations, a profile that is more similar to adenocarcinoma than squamous cell carcinoma. They also have a worse prognosis than the other types of non-small cell lung carcinoma. Many large cell carcinomas previously classified on morphological data alone are now reclassified in the adenocarcinoma and squamous cell carcinoma types, including immunohistochemical features. The other large cell carcinoma subtypes from the 2004 WHO classification, i.e. large cell neuroendocrine carcinoma and basaloid carcinoma, are grouped respectively with the other neuroendocrine tumors and squamous cell carcinomas. Clear cell and rhabdoid features are now considered as cytological variants that can occur in any histopathological subtype and not as distinct subtypes. Lymphoepithelioma-like carcinoma is moved to the group of other and unclassified carcinomas as NUT carcinoma.

The precise distinction between adenocarcinoma and squamous cell carcinoma (SqCC) has become very important for determining the appropriate therapy for patients and more specifically to drive the use of tyrosine kinase inhibitors, pemetrexed, anti-VEGF monoclonal antibody and crizotinib. Squamous pearls and distinct intercellular bridges identify keratinizing SqCC. In non-keratinizing SqCC, immuno-histochemistry is required. Recent studies have shown p40 and TTF1 to be the two best markers of SqCC and adenocarcinoma respectively. Many morphological variants of SqCC have been described. Basaloid SqCC is a poorly differentiated epithelial tumor lacking squamous morphology but showing immuno-histochemical expression of squamous makers. The pronostic of basaloid carcinoma is considered poorer than that of other non-small cell lung cancers. Adenosquamous carcinoma shows components of both SqCC and adenocarcinoma. Both components must be clearly identified either on HE or by immuno-histochemistry. The adenocarcinoma components justified a screening for gene rearrangements. Finally, the recent WHO classification of lung tumors did not change the criteria applying for the grading of preinvasive bronchial lesion.

Understanding adaptive signaling pathways in response to chemotherapy is one of the main challenges of cancer treatment. Activated in response to DNA damage, cell cycle and mitotic checkpoints activate the p53-p21 and p16-Rb pathways and induce apoptosis or senescence. Since senescent cells survive and produce a secretome that influences neighbouring cells, it is not particularly clear whether these responses are equivalent and if tumor cells escape these two suppressive pathways to the same extent. Predicting escape is also complicated by the fact that cancer cells adapt to treatments by activating the epithelial-mesenchymal transition and by producing clones with cancer-initiating cells features. Dedifferentiation pathways used in stressful conditions reconstitute dividing and sometimes more aggressive populations in response to chemotherapy. These observations illustrate the importance of tumor heterogeneity and the adaptation capacities of different intra-tumoral subclones. Depending on their oncogenic profile, on their localisation within the tumor and on their interaction with stromal cells, these subclones are expected to have different responses and adaptation capacities to chemotherapy. A complete eradication will certainly rely on combination therapies that can kill at the same time the bulk of the sensitive tumor but can also prevent plasticity and the generation of persistent clones.

The development of molecular biology tools has allowed major advances in the genetic determinism and the pathophysiology of pheochromocytomas and Conn's adenomas. However, the molecular pathophysiology of ACTH-independent Cushing's Syndrome was mostly unknown until recently. In 2014, major new insights concerning the physiopathology of ACTH-independent macronodular adrenal hyperplasias (AIMAH) and the cortisol-secreting adenomas have been published. Elsewhere, the cardiovascular consequences of the subclinical hypercortisolism due to adrenal incidentalomas, was described only in some cross-sectional studies. The natural history of these lesions has been documented in two large follow-up studies. These new data presented during the Endocrine Congress are summarized herein.

The transcription factor CTIP2 (BCL11B) is a multifunctional protein involved in numerous cell physiological processes. To date, many molecular mechanisms underlying this process have been discovered, which highlighted the importance of the epigenetic regulation of genes and the regulation of the elongation factor P-TEFb. Furthermore studies of the deregulation of CTIP2 showed the association of CTIP2 to numerous pathologies including cancer and cardiac hypertrophy. A better comprehension of the physiopathology of these diseases might lead to the design of therapeutical strategies intending to prevent CTIP2 deregulation. Moreover, CTIP2 and its associated proteins constitute potential targets in strategies aiming to reduce and/or purge HIV-1 cell reservoirs.

PML/TRIM19 is the organizer of PML nuclear bodies (NB), large multiprotein structures associated to the nuclear matrix, which recruit a great number of proteins and which are implicated in various cellular processes including antiviral defense. The conjugation of PML to SUMO is required for the formation and function of PML NB. Alternative splicing from a single PML gene generates several PML isoforms (PMLI to PMLVIIb), each harboring a specific carboxy-terminal region. This variability allows each isoform to recruit different partners and thus confers them specific functions. PML gene is directly induced by interferon and certain PML isoforms are implicated in its antiviral properties, as they display intrinsic antiviral activities against RNA or DNA viruses. One isoform, PMLIV, is also implicated in innate immunity by enhancing IFN-β production during a viral infection. Here we review recent findings on PML/TRIM19 implication in interferon response and antiviral defense, at the interface between intrinsic and innate immunity.

Cutaneous melanoma is a multifactorial disease resulting from both environmental and genetic factors. Five susceptibility genes have been identified over the past years, comprising high-risk susceptibility genes (CDKN2A, CDK4, and BAP1 genes) and intermediate-risk susceptibility genes (MITF, and MC1R genes). The aim of this expert consensus was to define clinical contexts justifying genetic analyses, to describe the conduct of these analyses, and to propose surveillance recommendations. Given the regulatory constraints, it is recommended that dermatologists work in tandem with a geneticist. Genetic analysis may be prescribed when at least two episodes of histologically proven invasive cutaneous melanoma have been diagnosed before the age of 75 years in two 1st or 2nd degree relatives or in the same individual. The occurrence in the same individual or in a relative of invasive cutaneous melanoma with ocular melanoma, pancreatic cancer, renal cancer, mesothelioma or a central nervous system tumour are also indications for genetic testing. Management is based upon properly managed photoprotection and dermatological monitoring according to genetic status. Finally, depending on the mutated gene and the familial history, associated tumour risks require specific management (e.g. ocular melanoma, pancreatic cancer). Due to the rapid progress in genetics, these recommendations will need to be updated regularly.

Whereas the classic dogma postulates that transmembrane receptors remain inactive at the plasma membrane unless bound by their specific ligand, it was suggested that some receptors may actually be active not only in the presence of their ligand, but also in their absence. In this latter case, the signaling downstream of these unbound receptors leads to apoptosis. These receptors were consequently named dependence receptors, as their cell expression renders the survival of the cell dependent on the presence in the cell environment of its respective ligand. This dual function - positive in the presence of ligand, negative in the absence of ligand - is hypothesized to lead these receptors to have key roles both during embryonic development and in the regulation of tumorigenesis. In the context of cancer, the hypothesis is that these receptors are tumor suppressors that would limit tumor progression by inducing apoptosis of tumor cells outside of settings of ligand accessibility/availability. This was recently formally demonstrated for the prototypical dependence receptors that bind netrin-1- i.e., DCC and UNC5H. Because expression of DCC and UNC5H is a constraint for tumor progression, their expression is often lost in many aggressive cancers. However, a loss of dependence receptors is not always the selective advantage used by tumor cells to escape this survival dependence on the presence of the ligand. Indeed, it was shown that in many cancers, tumor cells acquire the preferred autocrine expression of ligands of dependence receptor. This selective advantage for the tumor is much more appealing in terms of therapeutic opportunities. Drugs based on the interference on the interaction between dependence receptors and their ligands allow tumor cell death in vitro and trigger tumor growth and metastases inhibition in mice. This review describes how a basic cell biology concept has provided in a near future new tools to fight cancer.

Cancer is now the leading cause of mortality in France. It has been clearly demonstrated that mutations in the genetic information is the initiating event of cancer. DNA damage such as DNA double-strand breaks leads to genomic instability and cancer development. Cells can repair DNA double-strand breaks through several mechanisms. Nevertheless, only homologous recombination repair is faithful and repairs DNA without creating mutations. Here, we review the roles of PALB2 and BRCA2 in homologous recombination and genome stability.

Multiple familial trichoepithelioma (MFT) is an autosomal dominant disease characterized by the development of numerous skin-coloured papules on the central area of the face. It is associated with various CYLD gene mutations that are also responsible for familial cylindromatosis and Brooke-Spiegler syndrome.We report a novel mutation in the CYLD gene in a family with MFT and discuss new developments in therapeutic options.Recent studies indicate that CYLD is a tumour-suppressor gene.

A 61-year-old man, with a tuberous sclerosis, experienced severe acute reactions during a concomitant chemoradiotherapy regimen after 22Gy and one cycle of 5-fluorouracil-cisplatinum. He was treated for a cervical squamous cell lymph node of unknown origin. Grade 3 mucitis and epitheliitis were observed only in the irradiated fields and required the end of the radiotherapy. Tuberous sclerosis is characterized by a loss of the TSC2 function, with a permanent activation of the mTOR pathway. Logically, some kind of "radioresistance" should be observed. Increased radiosensitivity is paradoxical. This case illustrates how radiosensitivity is a complex phenomenon and clinically unpredictable. Efficiency of the protocols associations of mTOR inhibitors and radiotherapy should be carefully scrutinized.

International audience; The TP53 family member TP63 encodes two main isoforms TAp63 and ΔNp63 with distinct, often opposite functions during development and in the adult. ΔNp63 is crucial for the formation of the ectodermal derivatives and epidermis, while TAp63 is essential for heart development. In the adult, ΔNp63 behaves as a cell survival factor, controlling cell proliferation, adhesion and cell differentiation. In contrast, TAp63 is a proapoptotic factor that protects oocytes from genotoxic insults and prevents premature aging of dermal stem cells. In agreement with these activities, TAp63 is often lost and ΔNp63 overexpressed in cancer cells. Because of their opposite and competitive effects, p63 isoforms could be viewed as Janus two faces. The review focuses on the accumulating data on the p63 functions and regulation in the last decade.

One of the major advance concerning skin carcinoma is the development of targeted therapy: anti-patch/sonic/hedgehog for basal cell carcinoma (BCC) and anti-EGFR for squamous cell carcinoma (SCC). These therapies are indicated for advanced non surgically removable tumors. Their anti-tumoral efficacy has been shown, their effect seems to be suspensive which raises the question of their tolerability for long term use. Laboratory work have shown that BCC and SCC stem cells locate in different cell compartments and follow distinct molecular events which explains their distinct behaviour. The role of HPV in EBDR skin cancers has been ruled out. Photodynamic therapy induced-immunosuppression can be prevented by lowering the light fluence. The gene responsible for the Ferguson Smith syndrome has been identified: it is the gene encoding TGFBR1. Its implication in SCC needs to be determined. A new compound, PEP005, (ingenol mebutate) should soon enlarge therapeutical options for actinic keratosis. Concerning melanoma, results of the two phase III studies using two innovative therapies (anti-Braf and ipilimumab) have been published. Comparative study between anti-Braf and DTIC has shown a response rate of 48.4 % with vemurafenib and 5.5 % with DTIC. The risk of death was diminished by 67 %. These results have allowed to switch to vemurafenib patients with progression under DTIC. However, the initial response is followed by relapse in a majority of cases. Mechanisms of this resistance have been studied and the inhibition of several molecules involved in different or identical pathway should help to resolve that problem. The combination ipilimumab+ DTIC gives better results than DTIC alone. The adverse events of this association are slightly different than those seen with ipilimumab alone. They must be known by prescribers. Some discussions are on their way between the two companies developping anti-Braf and ipilimumab to develop therapeutic strategies combining both treatments. 20 to 30 % of patients taking anti-Braf drugs will develop SCC (due to paradoxal activation of MAPK in non Braf mutated cells). PEG-interferon seems to be indicated in ulcerated melanoma with lymph node micrometastasis. Some other targeted molecules such as C-KIT and anti-MEK are under evaluation. The effect of sunscreens on melanoma risk prevention has been reported in an Australian study. A low vitamine D status is reported to have a bad prognosis in melanoma and is observed in fair skin patients at risk. Recommendations for the care and follow up of patients with Merkel carcinoma have been published. The elevated risk of positive sentinel lymph nodes in these patients does not allow to define a subgroup of Merkel patients that could be spared from the technique. Sarcoma also benefit from targeted therapy especially DFSP with imatinib. Other molecules among which mTOR inhibitors are being evaluated in sarcomas. A collaborative work has allowed to classify and evaluate in a more standardized way cutaneous T lymphomas and should help future trials. Some microRNA can be used as diagnostic tools or therapies in T cell cutaneous lymphomas. Finally a review of modern therapeutical strategies in cutaneous lymphomas has been published.

International audience; With the approval of mechlorethamine by the FDA in 1949 for the treatment of hematologic malignancies, alkylating agents are the oldest class of anticancer agents. Even though their clinical use is far beyond the use of new targeted therapies, they still occupy a major place in specific indications and sometimes represent the unique option for the treatment of refractory diseases. Here, we are reviewing the major classes of alkylating agents and their mechanism of action, with a particular emphasis for the new generations of alkylating agents. As for most of the chemotherapeutic agents used in the clinic, these compounds are derived from natural sources. With a complex but original mechanism of action, they represent new interesting alternatives for the clinicians, especially for tumors that are resistant to conventional DNA damaging agents. We also briefly describe the different strategies that have been or are currently developed to potentiate the use of classical alkylating agents, especially the inhibition of pathways that are involved in the repair of DNA lesions induced by these agents. In this line, the development of PARP inhibitors is a striking example of the recent regain of interest towards the "old" alkylating agents.

The IKKε kinase, an atypical member of the IKK family of kinases, was recently identified as an oncogene overexpressed in over 30% of breast cancers. Besides its role in the regulation of the NF-κB transcription factor, which is well recognized for its implication in the development of breast cancers, IKKε was shown to phosphorylate numerous targets. Analysis of the phosphorylation of some of these substrates in the context of breast cancer highlighted new oncogenic signaling pathways that constitute potential targets for new therapies. Interestingly, IKKε is involved in the development of resistance to Tamoxifène. Thus, IKKε is a promising therapeutic target for newly developed breast cancer treatment.

CYLD deubiquitinase has been originally defined as a tumor suppressor based exclusively on genetic findings. Indeed, inactivation of CYLD in humans results in familial cylindromatosis and multiple trichoepithelioma, two pathologies characterized by the development of tumors originating specifically from the skin appendages. A set of recent publications has revealed that recurrent inactivation of CYLD occurs through diverse mechanisms in several forms of cancer, unequivocally confirming its tumor suppressor function. This property is associated with the critical role played by CYLD in negatively regulating several signaling pathway, among them the NF-κB signaling pathway.

Genomic DNA is constantly under stress of endogenous and exogenous DNA damaging agents. Without proper care, the DNA damage causes an alteration of the genomic structure and can lead to cell death or the occurrence of mutations involved in tumorigenesis. During the process of evolution, organisms have acquired a series of response mechanisms and repair of DNA damage, thereby ensuring the maintenance of genome stability and faithful transmission of genetic information. The checkpoints are the major mechanisms by which a cell can respond to DNA damage, either by actively stopping the cell cycle or by induction of apoptosis. Two parallel signalling pathways, ATM and ATR respond to genotoxic stress by activating their downstream target proteins including the two effectors kinases CHK1 and CHK2. Promising preliminary data render these proteins potential targets for therapeutic development against cancer.

Numerous parameters influenced tumour radiosensitivity. The number of clonogenic cells, growth fraction, hypoxia and intrinsic radiosensitivity are among the most important determinants of radiocurability. Detection of DNA damage and repair pathways are important components of intrinsic radiosensitivity. ATM plays a major role in the cellular response to ionizing radiation: it induced DNA repair, cell cycle arrest, and apoptosis via induction of p53. Analysis of single nucleotide polymorphisms could help us to predict normal tissue sensitivity on an individual basis. Mutations of ATM is probably involved in some cases of severe radiation-induced late effects. Measure of residual double-strand breaks by immunochemistry of H2AX, but also ATM or MRE11, is another way to evaluate tumour radiosensitivity. Integration of genomics and functional approach are needed to better predict what the best candidates for a curative radiotherapy are.

This review focuses on new aspects in growth hormone (GH) biology and pathophysiology presented at the Endocrine Society's meeting, in San Diego, in June 2010. First, we will describe recent advances in the understanding of cytokine hormone signaling via STAT5 in mammary gland development, highlighting the primary role of miR193b for differentiation of mammary stem cells into alveolar progenitor cells. We will examine the potential implication of endocrine and autocrine GH for mammary gland carcinogenesis. Three novel murine models bearing tissue-specific inactivation of GH receptor or JAK2 bring new insights into the large spectrum of GH effects on energy homeostasis. We will also report new data supporting a paracrine regulation of GH secretion in women by estrogen's action in the brain. Thereafter we will question the reasons for GH abuse for doping by assessing the hormonal impact on body composition and physical performance in recreational athletes. Finally, we will discuss the controversial issue of GH replacement in acromegalic patients presenting GH deficiency after treatment of acromegaly.

This presentation reports a series of data dealing with recurrent genetic abnormalities and gene expression profiles that characterize primary glioblastomas and secondary glioblastomas resulting from the transformation of low grade tumors (grade II and III astrocytomas and oligodendrogliomas). The most recent aspects of the concept of tumor stem cells that may explain the relentless growth of GBM will be reported. Molecular features of tumor neoangiogenesis will be described. Epigenetic alterations and deregulation of gene expression by microRNAs (miRs) will be also included. Some aspects of tumor predisposition will be also discussed. Finally, a short description of exosomes as vectors of tumor information will be presented.

New perspectives for radiosensitization in hepatocellular carcinoma (HCC) have emerged with the increasing knowledge of mechanisms involved in liver oncogenesis. As a matter of fact, some of these mechanisms have also a role in the response to ionizing radiation. We review some of the major molecular pathways involved in the oncogenesis of hepatocellular carcinoma. These include cellular proliferation pathways, repair systems, apoptosis, and angiogenesis. However, there are few preclinical data on concurrent targeted therapies and ionizing radiation in hepatocellular carcinoma models. Preliminary studies are ongoing. Their results might help to better define the potential benefit of such radiosensitizing strategies in the management of hepatocellular carcinoma.

The medical treatment of renal-cell carcinoma, and of its most frequent subtype, clear cell renal-cell carcinoma, has recently been drastically changed by the emergence of targeted therapies. The development of these drugs has been made possible by more precise knowledge of molecular mechanisms involved in the carcinogenesis of these tumors. We present in this article the molecular pathways linked to targeted therapies for clear cell renal-cell carcinoma: VHL/HIF/VEHF and PI3K/AkT/mTOR pathways. We also describe succinctly the EGFR pathways, and the molecular mechanisms involved in other histological subtypes. Then, we briefly describe how these targeted therapies work. We finally discuss how biology could improve the use of these therapies, by developing new prognostic factors, and predictive factors of response to treatment.

Tuberous sclerosis complex is a genetic multisystem disease characterized by hamartic development of many organs, most notably the brain, heart, kidneys, lungs, and skin. This autosomic dominant disorder results from mutations in one of two genes, TSC1 and TSC2, coding for hamartin and tuberin, respectively. The hamartin-tuberin complex inhibits the mammalian target of rapamycin pathway, which controls cell growth and proliferation. The clinical presentation is highly variable and most features of tuberous sclerosis become evident only in childhood after the child is several years of age, limiting their usefulness for early diagnosis. The aim of this article is to define the pediatric clinical manifestations of tuberous sclerosis in correlation with patient age. Sometimes, a prenatal diagnosis can be made based on fetal ultrasound and MRI, which show cardiac and brain lesions. However, newborns are most often asymptomatic. In the 1st year, seizures are the most common symptoms, with a high incidence of infantile spasms. In children between 2 and 10 years of age, neurological symptoms are the most frequent with epilepsy, mental retardation, and autism, but extraneurological manifestations can be diagnosed. In adolescents, most features of tuberous sclerosis become evident and renal and pulmonary manifestations must be sought. The knowledge of age-dependent clinical features of tuberous sclerosis can provide an earlier diagnosis and improve the management of these patients with a special role for multidisciplinary consultation.

The Birt-Hogg-Dubé (BHD) syndrome is associated with cutaneous disorders including fibrofolliculomas and trichodiscomas, and also lung pneumatocysts and kidney tumours. The BHD syndrome occurs as a consequence of an autosomal dominantly inherited genodermatosis, linked to multiple germline mutations in the 14 exons of the BHD gene, mapped on 17p11.2 and encoding for folliculin (FLCN). The size and number of lung pneumatocysts are extremely variable and the cysts are surrounded by normal pulmonary tissue. In the absence of smoking lung function is usually unimpaired. The lung cysts are frequently complicated by the development of recurrent pneumothoraces. Treatment of pneumothorax in patients with the BHD syndrome is similar to the approach taken for patients with spontaneous pneumothorax. Lung cysts in the BHD syndrome are a rare cause of cystic pulmonary lesions. However, they must be systematically evaluated since kidney tumours occur in one third of patients. We report a case of classical BHD syndrome with specific cutaneous involvement, recurrent pneumothoraces complicating lung cysts, an exon 12 germline mutation on BHD gene and a familial history suggesting other related cases. This observation allows us to update this orphan disease, to consider BHD in the differential diagnosis of lung cysts and, above all, to highlight the high frequency and the prognostic significance of associated kidney tumours.

National audience; Lymphangioleiomyomatosis is a rare pulmonary disease encountered almost exclusively in women of reproductive age. Pulmonary involvement is characterized by multiple thin-walled cysts in the lungs, recurrent pneumothorax, obstructive lung disorders, and progression to chronic respiratory failure over a mean period of 10 years. Certainty of diagnosis requires a lung biopsy, but international criteria have been proposed for a diagnosis without such a biopsy. International recommendations were recently issued for the diagnosis and treatment of lymphangioleiomyomatosis. Treatment is principally symptomatic and relies on the management of bronchial obstruction by bronchodilators; of hypoxemia by oxygen therapy; of pleural complications by pleurodesis, most often surgical; and of renal angiomyolipomas by percutaneous embolization in cases of hemorrhagic risk. Hormone treatment is not recommended. Hopes are high for mTor inhibitors (sirolimus and everolimus) and treatment trials are currently underway. Lung transplantation must be considered when chronic respiratory failure occurs in patients younger than 60 years.; La lymphangioléiomyomatose est une maladie pulmonaire rare rencontrée quasi exclusivement chez la femme en période d’activité génitale. L’atteinte pulmonaire est caractérisée par des kystes pulmonaires multiples à parois fines, des pneumothorax récidivants, un trouble ventilatoire obstructif, et une évolution vers l’insuffisance respiratoire chronique dans un délai moyen de 10 ans. Le diagnostic de certitude repose sur la biopsie pulmonaire, mais des critères diagnostiques internationaux ont été proposés pour le diagnostic en l’absence de biopsie pulmonaire. Des recommandations internationales ont été récemment établies pour le diagnostic et la prise en charge thérapeutique de la lymphangioléiomyomatose. Le traitement est principalement symptomatique, et repose sur la prise en charge de l’obstruction bronchique par les bronchodilatateurs ; de l’hypoxémie par l’oxygénothérapie ; des complications pleurales par pleurodèse le plus souvent chirurgicale ; des angiomyolipomes rénaux par embolisation percutanée en cas de risque hémorragique. Le traitement hormonal n’est pas recommandé. Des espoirs reposent sur les inhibiteurs de mTOR (sirolimus et évérolimus) pour lesquels des essais thérapeutiques sont en cours. La transplantation pulmonaire doit être proposée en cas d’insuffisance respiratoire chronique avant l’âge de 60 ans.

The p73 gene encodes a nuclear protein that is highy homologous to p53. p73 also shares some common functions with p53 protein indicating that p73 gene is a p53-like tumor suppressor.In this study, we examined by immunohistochemestry the p73 expression on 120 cases of colorectal carcinomas and evaluated its implication in carcinogenesis.Retrospective study.The results show an increase of intensity and distribution of p73 in common adenocarcinoma from the normal mucosa, to primery tumors and to metastases. However, in mucinous adenocarcinomas, immunostaining of p73 decrease in primary tumor and completely diseappears in isolated cells and metastases compared with matched normal mucosa. These observations are further reinforced by the fact that in adenocarcinoma with mucinous component less than 50%, the positivity of p73 persist in well-differentiated areas and dramatically decreases or completely deseappears in mucinous areas.In conclusion, p73 would be a prognosic marker for the common adenocarcinomas and an ethiopathogenic factor for the mucinous subtype.

Pancreatic adenocarcinoma, with an incidence/death ratio of 0.99, has the worst prognosis of all cancers. Risk factors associated with the sporadic form of pancreatic adenocarcinoma are unknown and less than 10% of patients receive curative treatment (surgery associated with radiation therapy or chemotherapy) with a low 5-year survival rate (10 to 20%). In more than 90% of patients, the tumor discovered at diagnosis is not resectable or has already metastasized. Thus, a better understanding of the etiology of pancreatic cancer is essential to identify new prognostic markers and new therapeutic targets. There is a wealth of data on the identification of genetic alterations associated with pancreatic cancer and their role in its development. This review will focus on the current knowledge of genetic alterations associated with two pancreatic lesions that can potentially evolve into pancreatic adenocarcinoma, Pancreatic Intraepithelial Neoplasia (PanIN) and Intraductal Papillary Mucinous Neoplasm (IPMN). These two lesions share a large panel of typical genetic alterations which are close to those found in pancreatic adenocarcinoma. A better understanding of these alterations may lead to therapeutic targets that could help prevent the progression of PanIN and IPMN to cancer.

Birt-Hogg-Dubé syndrome (BHDS) is an autosomal-dominantly inherited genodermatosis that predisposes to the development of benign hair follicle tumours, lung cysts, kidney tumours, and possibly colonic cancers, due to mutations in the FLCN gene. We report cases involving a new mutation in three unrelated families.Blood samples of three probands were submitted for a molecular diagnosis of BHDS. Following DNA extraction, FLCN gene sequencing was performed. The identified mutations were confirmed on a second sample. A cancer genetics consultation was organized and specific tests (dermatological examination, CT scan of chest and abdomen and colonoscopy) were proposed for each BHDS patient.FLCN gene-sequencing analysis revealed an identical complex harmful mutation in all three families. The first proband showed fibrofolliculomas (FF), a history of pneumothorax and colonic adenoma. The mutation was found in a brother and two sisters, who were asymptomatic, and in a niece with FF. The second proband showed FF. The mutation was found in her mother, who had FF. The third proband presented diffuse emphysema and very rare FF.This case report shows extremely wide intra- and interfamilial phenotype variation within individuals having a similar FLCN gene mutation. In large cohorts of BHDS patients, no genotype-phenotype correlation has been shown. This case emphasises the vital importance of presymptomatic diagnosis for each member of a BHDS family by means of a cancer genetics consultation, followed by a CT scan of the chest and abdomen, colonoscopy and annual kidney imaging.

Despite the development of new chemotherapy regimens, including platinum-containing combinations, the prognosis of NSCLC remains very poor. Advances in the understanding of cancer biology and more specifically, of cell signalling pathways have led to the identification of several potential molecular targets and to the development of new agents directed against these targets. The most advanced molecular therapies target the EGF (epidermal growth factor) receptor and the angiogenesis pathway. Despite this progress, treatment efficacy (molecularly-targeted therapy or chemotherapy) appears to be very heterogeneous across patients. The current challenge is to be able to define the most relevant patient-tailored treatment, based on clinical, histological or biological markers, in order to improve the benefit and tolerance of antitumor treatments. Discovering new prognostic or predictive biomarkers for lung cancer is one of the main objectives of translational cancer research.

Dysfunction of the ataxia telangiectasia mutated (ATM) gene has been related to defective cell cycle control and genomic instability due to the impaired repair of DNA double strand breaks. Although increased radiosensitivity in ATM heterozygous patients has been suggested in preclinical data, clinical implication of ATM variant remains debated. Despite frequent in vitro hypersensitivity in patients with severe radiation-induced delayed toxicity, heterozygoty for ATM gene does not represent the major cause of unexpected complications after radiation therapy. This might be partially due to potential coexistence of alterations in additional genes that would play a role in development of late radiation-induced adverse response. Although several data suggest that some ATM polymorphisms would increase grade 3 subcutaneous fibrosis at lower doses compared with patients who did not possess these genetic alterations, the relationship between the presence of ATM mutations or sequence variants and radiation-induced toxicity remains controversial in part because of their biological and functional significance. Considering the lack of prospective data, patients with ATM mutation should be considered as candidates for both dose volume and dose reduction clinical trials.

International audience; CURRENT SITUATION: Early detection of the relapse in case of tumor located in the upper aerodigestive tract (UADT) is an important point for improving prognosis. Clinical control has not been efficient and, until today, no biological biomarker has been validated for surveillance of patients. In a preliminary study, we have shown the benefit of the methylation status of six tumor suppressor genes (TSG): TIMP3, ECAD, p16, MGMT, DAPK, and RASSF1A in saliva for early diagnosis of tumor relapse. The main objective of this second study is to confirm the initial results. MATERIAL AND METHODS: This is a bicenter, prospective, diagnostic, single-blind study. The study started in December 2007, running for one year. The main inclusion criterion is a patient with squamous-cell carcinoma of the oral cavity or the oropharynx, stages I to II, without previous treatment for this location. Eighty patients will be included. The data analysis will use a multivariate Cox model. EXPECTED RESULTS: If our preliminary results are confirmed, identification of methylations in saliva would be able to constitute the first usuable biomarker, for the follow-up of patients with UADT cancer.