p27 (Kip1) role as a transcriptional regulator

p27, also called Kip1, is a well known protein with a crucial role in cell cycle progression and cancer. p27 best known function is the inhibition of cyclin-dependent kinase (cdk) activities, cyclin E-CDK2 and cyclin D-CDK4 complexes, and has a role in controlling the cell cycle progression at G1. However it was unclear if p27 may have other roles in the nucleus other than acting as a CDK inhibitor.

paper published this week in Oncogene shows that p27 has also a role as a transcriptional repressor, which is independent of cyclin-cdk regulation. This work has been leaded by Oriol Bachs and Raffy Pippa from IDIBAPS, and we, Gunes and myself, and other researchers from IMIMCIEMAT and University of Toulouse have participated in the project.

Model illustrating the participation of p27 on the organization of p130/E2F4 repressor complexes. p130 first drives E2F4 to the promoters, then p27 is subsequently loaded by directly interacting by its carboxyl-domain with both p130 and E2F4. Finally, p27 recruits the co-repressors HDAC1 and mSIN3A on these promoters.

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Finding correlated genes on TCGA expression data.

We have published a new section in IntOGen in collaboration with Hautaniemi Lab, where you can do a gene correlation with the gene expression results of TCGA (The Cancer Genome Atlas) for a given subset of patients that share some specific clinical annotations. Then you will be able to browse your correlations next to global gene expression, SNP survival and DNA methylation analyses. The data analyzed so far includes 4 tumor types from TCGA: glioblastoma multiforme (GBM; 507 samples), ovarian serous adenocarcinoma (OV; 546 samples), breast invasive carcinoma (BRCA; 525 samples) and colon adenocarcinoma (COAD; 161 samples).

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