Maurice Stroun

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Studies on a range of prokaryote and eukaryote cells and tissues have shown that a newly synthesized DNA/RNA-lipoprotein complex is released in a regulated manner. This complex, termed a virtosome, is a novel cytosolic component of eukaryote cells. The released virtosomes can readily enter other cells where they can modify the biology of the recipient(More)
Tumor-derived circulating DNA has been found in the plasma of cancer patients. Alterations include decreased strand stability, mutations of oncogenes or of tumor suppressor genes, microsatellite alterations, and hypermethylation of several genes. RNA has also been found circulating in the plasma of normal subjects and cancer patients. Tyrosinase mRNA has(More)
BACKGROUND In addition to cell lysis, apoptosis has been advanced as the origin of circulating DNA on the basis of several observations. Plasma or serum DNA often presents a ladder pattern reminiscent of that displayed by apoptotic cells when subjected to electrophoresis. However, the phenomenon of active release of DNA from cells might also be expected to(More)
It has been proposed that cell-free nucleic acids in the plasma participate in tumorigenesis and the development of metastases via transfection-like uptake of such nucleic acids by susceptible cells. This putative phenomenon is tentatively referred to as "genometastasis." In the present study, we examined the effects on cultured cells of plasma from healthy(More)
A DNA fraction is spontaneously released from living, but not dead or dying, human, other mammalian, avian, amphibian, plant, and prokaryote cells. The spontaneously released DNA fraction has been shown to be (a) present in both actively dividing and nondividing, differentiated cell populations; (b) labile; (c) associated with DNA-dependent RNA or DNA(More)
Cell systems as different as normal human blood lymphocytes and frog auricles release spontaneously a nucleoprotein complex in their culture medium. This release seems to be an active mechanism that is unrelated to cell death. The presence of RNA in this complex is demonstrated. The amount of extracellular RNA is regulated by the same homeostatic mechanism(More)
Human blood lymphocytes released DNA in vitro in the absence of any stimulation. Once purified from the complex appearing in the supernatant, this DNA exhibited typical characteristics as shown by its UV absorption curve, its deoxyribose coloration, and its sensitivity to DNase. Elution patterns on hydroxyapatite columns indicated that the excreted DNA is(More)
While various clinical applications especially in oncology are now in progress such as diagnosis, prognosis, therapy monitoring, or patient follow-up, the determination of structural characteristics of cell-free circulating DNA (cirDNA) are still being researched. Nevertheless, some specific structures have been identified and cirDNA has been shown to be(More)
Chromosomal abnormalities are associated with the development of breast cancer, and widespread allelic loss or imbalance is frequently found in tumor tissues taken from patients with this disease. Using different markers, we studied a total of 61 patients (divided into three groups) for the presence of microsatellite instability and loss of heterozygosity(More)