Alpha-fetoprotein controls female fertility and prenatal development of the gonadotropin-releasing hormone pathway through an antiestrogenic action

peer reviewedIt has been shown previously that female mice homozygous for an alpha-fetoprotein (AFP) null allele are sterile as a result of anovulation, probably due to a defect in the hypothalamic-pituitary axis. Here we show that these female mice exhibit specific anomalies in the expression of numerous genes in the pituitary, including genes involved in the gonadotropin-releasing hormone pathway, which are underexpressed. In the hypothalamus, the gonadotropin-releasing hormone gene, Gnrh1, was also found to be down-regulated. However, pituitary gene expression could be normalized and fertility could be rescued by blocking prenatal estrogen synthesis using an aromatase inhibitor. These results show that AFP protects the developing female brain from the adverse effects of prenatal estrogen exposure and clarify a long-running debate on the role of this fetal protein in brain sexual differentiation

EML4-ALK translocation identification in RNA exosomal cargo (ExoALK) in NSCLC patients: a novel role for liquid biopsy

The introduction of druggable targets has significantly improved the outcomes of non-small cell lung cancer patients (NSCLC). EML4-ALK translocation represents 4–6% of the druggable alterations in NSCLC. With the approval of Crizotinib, first discovered drug for the EML4-ALK translocation, on first line treatment for patients with detected mutation meant a complete change on the treatment landscape. The current standard method for EML4-ALK identification is immunohistochemistry or FISH in a tumor biopsy. However, a big number of NSCLC patients have not tissue available for analysis and others are not suitable for biopsy due to their physical condition or the location of the tumor. Liquid biopsy seems the best alternative for identification in these patients that have no tissue available. Circulating free RNA has not been validated for the identification of this mutation. As a complementary tool, exosomes might represent a good tool for predictive biomarkers study, and due to their stability, they preserve the genetic material contained in them. Our group has described for the first time the translocation EML4-ALK in RNA isolated from exosomes derived from NSCLC patients using next generation sequencing

Recherche de gènes contrôlant le développement tumoral

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Recherche de gènes contrôlant le développement tumoral

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

The combined analysis of solid and liquid biopsies provides additional clinical information to improve patient care

Aim: To investigate if the genetic information provided by sequencing of both solid and liquid biopsies can shed light on tumor heterogeneity, and to understand the clinical usefulness of adding blood profiling to standard tissue analysis in cancer care.Methods: Data from 351 patients with stage IV solid tumors for whom molecular profiling of their solid and liquid biopsies was available were studied, with a focus on the discrepant molecular information found between tissue and blood samples.Results: In 86% of patients, solid and liquid biopsies provided different molecular information. Discrepant gene mutations with a functional impact on the corresponding protein were studied in detail. In 97% of cases, these additional mutations provided clinical value, mainly predicting sensitivity or resistance to targeted therapies. Specifically, 42% of the mutations found only in the liquid biopsy were directly predictive of approved therapies (80% targeted therapies), while 54% were inclusion criteria for molecularly-matched trials.Conclusion: This study suggests that the addition of blood profiling should be considered in routine clinical oncology, especially for patients with metastatic disease where integrated analysis of solid and liquid biopsies provides a more complete characterization of tumor heterogeneity and provides valuable clinical information for patient treatment

Evolution of miRNAs expression during lung squamous carcinogenesis.

Abstract OP12, page 171. Young Investigator Award Session, oral presentationinfo:eu-repo/semantics/nonPublishe

Evolution of microRNA expression during human bronchial squamous carcinogenesis.

MicroRNAs, negative post-transcriptional regulators of gene expression, are involved in cancer. Their role in early bronchial carcinogenesis was analysed in 60 biopsies obtained by fluorescence bronchoscopy (six per stage: normal tissue of nonsmokers, normal normofluorescent and hypofluorescent bronchial tissue of smokers, hyperplasia, metaplasia, mild, moderate and severe dysplasia, in situ carcinoma and invasive squamous cell carcinoma (SQCC)). In total, 69 microRNAs were found to be differentially expressed in the course of bronchial carcinogenesis. Among them, some microRNAs showed a linear evolution of their expression level, such as miR-32 and miR-34c, whose expression progressively decreased from normal bronchial tissues of nonsmokers to SQCC. Others behaved differently at successive stages, such as miR-142-3p or miR-9, or are only altered from a specific stage, such as miR-199a or miR-139. MicroRNAs globally followed a two-step evolution, first decreasing (a reverse of their increase during embryogenesis) during the earliest morphological modifications of bronchial epithelium, and thereafter increasing at later stages of lung carcinogenesis. Moreover, microRNA expression was very efficient for the prediction of the histological classification between low- and high-grade lesions and between in situ and invasive carcinoma. The present data show, for the first time, that microRNAs are involved in bronchial carcinogenesis from the very early steps of this process and, thus, could provide tools for early detection of lung cancer.Journal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Alterations of P19ARF in rodent hepatoma cell lines but not in human primary liver cancer

The tumor suppressor gene CDKN2A is functionally inactivated, through mutations, deletions, or methylation, in a large variety of primary neoplasms as well as tumor cell lines. The CDKN2A locus gives rise to two distinct transcripts. P16INK4 and P19ARF. Because it has been shown that the disruption of only P19arf-coding sequences in mice is sufficient for tumor development, this transcript most likely also encodes a tumor suppressor. We have analyzed the two CDKN2A transcripts in fifteen human primary liver carcinomas, two human hepatoma cell lines, and five rodent hepatoma cell lines. No homozygous deletions of P19ARF and P16INK4 were found in these samples, whereas the normal P19arf transcript was absent in two of the five rodent cell lines (nonexpressed in one case and mutated in another). These results suggest that functional abrogation of P19ARF is not a primary event in hepatocarcinogenesis.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Assignment of the rat pleiomorphic adenoma genes (Plag) by in situ hybridization and radiation hybrid mapping

Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

A second locus for autosomal recessive nonsyndromic optic atrophy

info:eu-repo/semantics/nonPublishe