Project description:Stat5 is a latent transcription factor that regulates essential growth and survival functions in normal cells. Constitutive activity of Stat5 and the involvement of its C-terminally truncated variant have been implicated in blood cell malignancies and mammary or breast cancer. To distinguish the individual contributions of the Stat5 variants to mammary tumorigenesis, global gene-expression profiling was performed on transgenic STAT5-induced tumors. Experiment Overall Design: Mammary tumors derived from transgenic mice carrying one of two Stat5 variants were collected for RNA extraction and hybridization on Affymetrix GeneChip® Mouse Genome 430A 2.0 array.
Project description:Stat5 is a latent transcription factor that regulates essential growth and survival functions in normal cells. Constitutive activity of Stat5 and the involvement of its C-terminally truncated variant have been implicated in blood cell malignancies and mammary or breast cancer. To distinguish the individual contributions of the Stat5 variants to mammary tumorigenesis, global gene-expression profiling was performed on transgenic STAT5-induced tumors.
Project description:Constitutively active AR variants are truncated proteins lacking the c-terminal region containing the ligand binding domain (LBD) and the activation function 2 (AF-2). The expression of these AR variants in CRPC was also associated with the resistance to novel therapies such as enzalutamide and abiraterone acetate. These variants are also involved in tumor progression.
Project description:Constitutively active AR variants are truncated proteins lacking the c-terminal region containing the ligand binding domain (LBD) and the activation function 2 (AF-2). The expression of these AR variants in CRPC was also associated with the resistance to novel therapies such as enzalutamide and abiraterone acetate. These variants are also involved in tumor progression.
Project description:The goal of this experiment was to compare the gene expression programs mediated by androgen/AR vs. constitutively active, truncated AR variants in castration-resistant CWR-R1 prostate cancer cells. Because constitutive activity of truncated AR variants can mask androgen/AR target genes, the androgen/AR transcriptional program was assessed by silencing the trucnated AR 1/2/3/CE3 variant with siRNA targeting AR exon CE3 and treating cells with vehicle (ethanol) or 1nM DHT. Similarly, because full-length AR activity can mask truncated AR variant target genes, the AR variant transcriptional program was assessed under castrate conditions by selectively silencing full-length AR with siRNA targeting AR exon 7, and comparing this profile with CWR-R1 cells transfected wtih siRNA targeting AR exon 1, which silences all AR expression (full-length and truncated AR variants).
Project description:Activation of canonical Wnt signaling is sufficient and necessary to inhibit the migration of the QR.pa neuroblast of C. elegans. To identify targets of canonical Wnt signaling involved in this process we isolated QR lineage descendants by FACS from control (mab-5(gk670) mutant) animals and animals expressing a constitutively active, N-terminally truncated form of BAR-1/β-catenin in the QR lineage using the egl-17 promoter (ΔN-BAR-1Q). FACS isolation was based on the expression of mCherry and GFP markers under the control of wrt-2 and egl-17 promoters, respectively. We performed differential gene expression analysis to identified genes that are differentially expressed between control and constitutive activation of canonical Wnt signaling.
Project description:Notch signaling is widely implicated in mouse mammary gland development and tumorigenesis. To investigate the effects of acute activation of Notch signaling in the mammary epithelial compartment, we generated bi-transgenic MMTV-rtTA; TetO-NICD1 (MTB/TICNX) mice that conditionally express a constitutively active NOTCH1 intracellular domain (NICD1) construct in the mammary epithelium upon doxycycline administration.
Project description:While PAX5 is an important tumor suppressor in B-ALL, it is also involved in oncogenic translocations coding for PAX5 fusion proteins. PAX5-JAK2 encodes a protein consisting of the PAX5 DNA-binding region fused to the constitutively active JAK2 kinase domain. Here, we studied the oncogenic function of PAX5-JAK2 in a mouse model expressing it from the endogenous Pax5 locus. The Pax5Jak2/+ mice rapidly developed an aggressive B-ALL in the absence of another cooperating mutation. The DNA-binding function and kinase activity of Pax5-Jak2, as well as IL-7 signaling, all contributed to leukemia development. Interestingly, all Pax5Jak2/+ tumors lost the wild-type Pax5 allele, allowing efficient DNA binding of Pax5-Jak2. While we could not find evidence for a nuclear role of Pax5-Jak2 as an epigenetic regulator, active phosphorylated Stat5 was present at a high level in Pax5Jak2/+ B-ALL tumors, consistent with increased expression of Stat5 target genes. Together, these data identified Pax5-Jak2 as an important nuclear driver of leukemia formation by maintaining phosphorylated Stat5 levels in the nucleus.
