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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.tibs.2009.09.005 Byline: Xavier Le Guezennec, Dmitry V. Bulavin Abstract: The PP2C family serine/threonine phosphatase WIP1 is characterized by distinctive oncogenic properties mediated by inhibitory functions on several tumor suppressor pathways, including ATM, CHK2, p38MAPK and p53. PPM1D, the gene encoding WIP1, is aberrantly amplified in different types of human primary cancers, and its deletion in mice results in a profound tumor-resistant phenotype. Numerous downstream targets of WIP1 have been identified, and genetic studies confirm that some play a part in tumorigenesis. Recent evidence highlights a new role for WIP1 in the regulation of a cell-autonomous decline in proliferation of certain self-renewing cell types, including pancreatic [beta]-cells, with advancing age. These emerging functions of WIP1 make it a potent therapeutic target against cancer and aging. Author Affiliation: Institute of Molecular and Cell Biology, Cell Cycle Control and Tumorigenesis Group, 61 Biopolis Drive, Proteos, Singapore 138673

A yeast two-hybrid screen was used to identify a novel binding partner ecotropic viral integration site 1 (Evi1), a methyl binding domain 3b (Mbd3b) protein, a member of the Mi-2/NuRD histone deacetylase complex. The results showed that interaction of Evi1 with Mbd3 requires 40 amino acids that are adjacent and downstream of the methyl binding domain (MBD).

Purpose: Tears are a particularly limited body fluid and commonly used in the diagnosis of patients who have ocular diseases. A popular method for analysis of ocular inflammation in tears uses Luminex® bead multiplex technology to generate valuable multiple cytokine profile outputs with 25-50 µl tear sample volume. We propose a method for measuring tear cytokines with 5 μl tear sample volume and 80% reduced Luminex reagents compared to previous protocols., Methods: Using human tears pooled from 1,000 participants, the DA-Bead-based method running at 5-20 µl volume, using manual pipetting, in conjunction with a magnetic Luminex cytokine (four-plex) panel assay in a 96-well format was performed and validated for tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-1β, and IL-6., Results: Upon use of the DA-Bead method at the 5 μl volume with cytokine standards, the concentrations of each of the four cytokines were found to be linear over a range of 3.5-4 log pg/ml with an intra-assay coefficient of variation (CV) ≤5%, inter-assay %CV ≤10%, and accuracy within the 70-130% range. Upon use of a 5 µl healthy pooled tear sample, cytokine concentrations were detected with a precision intra-assay %CV ˂ 20% for IL-6, IFN-γ, or TNF-α or 30.37% with IL-1β. The inter-assay %CV with tears was ≤20.84% for all cytokines. Tear volumes run at 5 μl on DA-Bead produced a similar cytokine expression profile at a 1-month interval and were highly correlated with the larger 10 μl-based tear sample volume cytokine profile with R(2) = 0.98., Conclusions: DA-Bead assay is highly sensitive and reproducible and has a performance profile that is potentially suitable for use in standard clinical scenarios. Considering the use of as little as 5 µl of assay beads and 5 µl sample, this is also likely to reduce the assay cost significantly and ease diagnosis of patients with ocular diseases.