Scale-free static and dynamical correlations in melts of monodisperse and Flory-distributed homopolymers: A review of recent bond-fluctuation model studies

It has been assumed until very recently that all long-range correlations are screened in three-dimensional melts of linear homopolymers on distances beyond the correlation length $\xi$ characterizing the decay of the density fluctuations. Summarizing simulation results obtained by means of a variant of the bond-fluctuation model with finite monomer excluded volume interactions and topology violating local and global Monte Carlo moves, we show that due to an interplay of the chain connectivity and the incompressibility constraint, both static and dynamical correlations arise on distances $r \gg \xi$. These correlations are scale-free and, surprisingly, do not depend explicitly on the compressibility of the solution. Both monodisperse and (essentially) Flory-distributed equilibrium polymers are considered.Comment: 60 pages, 49 figure

Chronic T cell receptor stimulation unmasks NK receptor signaling in peripheral T cell lymphomas via epigenetic reprogramming.

Peripheral T cell lymphomas (PTCLs) represent a significant unmet medical need with dismal clinical outcomes. The T cell receptor (TCR) is emerging as a key driver of T lymphocyte transformation. However, the role of chronic TCR activation in lymphomagenesis and in lymphoma cell survival is still poorly understood. Using a mouse model, we report that chronic TCR stimulation drove T cell lymphomagenesis, whereas TCR signaling did not contribute to PTCL survival. The combination of kinome, transcriptome, and epigenome analyses of mouse PTCLs revealed a NK cell-like reprogramming of PTCL cells with expression of NK receptors (NKRs) and downstream signaling molecules such as Tyrobp and SYK. Activating NKRs were functional in PTCLs and dependent on SYK activity. In vivo blockade of NKR signaling prolonged mouse survival, demonstrating the addiction of PTCLs to NKRs and downstream SYK/mTOR activity for their survival. We studied a large collection of human primary samples and identified several PTCLs recapitulating the phenotype described in this model by their expression of SYK and the NKR, suggesting a similar mechanism of lymphomagenesis and establishing a rationale for clinical studies targeting such molecules

Sequence analysis reveals that the BTG1 anti-proliferative gene is conserved throughout evolution in its coding and 3' non-coding regions

International audienc

Prognostic value of miR-16 expression in childhood acute lymphoblastic leukemia relationships to normal and malignant lymphocyte proliferation

International audienc

Change in valence of Ce ions induced by hydrogen absorption : CeRu2

Ternary hydrides of superconducting cubic Laves-phases CeRu2 and LaRu2 have been prepared. The cubic structure is preserved and a considerable lattice expansion is observed. Magnetic susceptibility measurements show the disappearance of the superconducting transition for both hydrides, and in the case of CeRu 2, the appearance of a susceptibility peak at T ∼ 1.4 K. For CeRu2 hydride, the hydrogen could be removed and superconductivity reestablished. Magnetization measurements of CeRu2 hydride and comparison of its lattice parameter with that of LaRu2 hydride indicate that, with hydrogenation, the valence of Ce has changed from 4 to 3.On a préparé les hydrures ternaires des composés supraconducteurs de structure cubique phase de Laves, CeRu2 et LaRu2. On constate, avec la conservation de la structure cubique, une forte dilatation du réseau. Pour les deux hydrures, des mesures de susceptibilité révèlent la disparition de la supraconductivité et, dans le cas de CeRu2, l'apparition d'une transition magnétique à T ∼ 1,4 K. Le CeRu2H x a pu être désorbé. Après désorption de CeRu2, la supraconductivité est rétablie. Les mesures de l'aimantation du CeRu2Hx et la valeur de sa constante de réseau, comparée à celle du LaRu2H x, semblent indiquer qu'avec l'hydrogénation, le cérium a changé de valence pour devenir trivalent

Post-transplant lymphoproliferative disorders with genetic abnormalities commonly found in malignant tumours

International audienc

Direct cooperation between androgen receptor and E2F1 reveals a common regulation mechanism for androgen-responsive genes in prostate cells.

We have studied the regulation of ATAD2 gene expression by androgens in prostate cells. ATAD2 is a coactivator of the androgen receptor (AR) and the MYC protein. We showed that ATAD2 expression is directly regulated by AR via an AR binding sequence (ARBS) located in the distal enhancer of its regulatory region. The gene is also regulated by the E2F1 transcription factor. Using knockdown and chromatin immunoprecipitation technique approaches, we could demonstrate that AR and E2F1 functionally collaborate and physically interact between each other. From the analysis of chromatin conformation, we conclude that this cooperation results from a chromatin looping over the ATAD2 promoter region between the ARBS and E2F1 binding site in an androgen-dependent manner. Furthermore, we could show that several genes overexpressed in prostate cancer and potentially involved in several aspects of tumor development have an ARBS and an E2F1 binding site in their regulatory regions and exhibit the same mechanism of regulation by both transcription factors as ATAD2

Cloning of the mouse BTG3 gene and definition of a new gene family (the BTG family) involved in the negative control of the cell cycle

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Quantitative Real-Time Reverse Transcription-PCR Assay for the Expression of Tob mRNA in Human Colorectal Cancer

OBJECTIVE Tob is a member of Tob/BTG antiproliferative family. To date, Tob expression in human carcinoma using clinical specimens has not been studied in depth except for lung carcinoma and thyroid carcinoma. This study is the first to investigate the expression levels of Tob gene in human colorectal cancer tissues, and their corresponding para-cancerous tissues. The correlation of expression of the Tob gene with clinicopathological characteristics of colorectal cancer was also analyzed. METHODS Quantitative real time RT-PCR was used to detect the expression of Tob mRNA in 31 colorectal cancers. RESULTS Compared with normal tissues, up-regulation of Tob mRNA was observed in 31 colorectal cancer tissues (P =0.020). The expression level of Tob at Dukes C + D phase was higher than Dukes A + B phase, and the difference was signifi cant (P < 0.05). However, in this study, it was found that the expression of Tob mRNA was not related with age, gender, and pathological type of colorectal cancer. CONCLUSION The up-regulation of Tob may be closely associated with tumorigenesis of colorectal carcinoma