Project description:1. Keratinocytes infected with retroviruses expressing control or SNAI2 shRNAs were cultured in growth medium and Affymetrix HG-U133 plus 2.0 arrays were used to determine global gene expression profiles. 2. Keratinocytes infected with retroviruses overexpressing LACZ or SNAI2 were cultured in growth medium and Affymetrix HG-U133 plus 2.0 arrays were used to determine global gene expression profiles. Keratinocytes with knockdown or overexpression of SNAI2 were used to determine gene expression profiles
Project description:Aim of the study was to characterize at a molecular level (changes in transcriptomes) the effect of monosodium urate crystal (MSU) on HaCaT keratinocyte cell line. This was adressed by using a culture model. The HaCaT cell line (human keratinocytes) was stimulated by MSU (1mg/mL) vs control for 12 hrs. By using genome-wide expression profiling, we identified deregulation of functionally relevant gene networks. HaCaT were obtained from Cell Lines Service (Eppelheim, Germany) and grown in DMEM medium (PAN biotech, Aidenbach, Germany) supplemented with 10% FBS (Life Technology, Grand Island, NY, USA), L-glutamine and non-essential amino acid. Before the treatment HaCaT cells were cultured in serum-free medium for 12hrs. HaCaT were treated with MSU (1mg/ml) vs DMEM control for 12hrs then submitted to RNA extration and gene expression profiling. Triplicate experiments were performed: HaCaT control (n=3), MSU-treated (n=3).
Project description:1. Keratinocytes infected with retroviruses expressing control or SNAI2 shRNAs were cultured in growth medium and Affymetrix HG-U133 plus 2.0 arrays were used to determine global gene expression profiles. 2. Keratinocytes infected with retroviruses overexpressing LACZ or SNAI2 were cultured in growth medium and Affymetrix HG-U133 plus 2.0 arrays were used to determine global gene expression profiles.
Project description:Constitutive activation of EGFR- and NF-kB-dependent pathways is a hallmark of cancer, yet signaling proteins that connect both oncogenic cascades are poorly characterized. Here we define KIAA1199 as a BCL-3- and p65-dependent gene in transformed keratinocytes. KIAA1199 expression is enhanced upon human papillomavirus (HPV) infection and is aberrantly expressed in clinical cases of cervical (pre)neoplastic lesions. Mechanistically, KIAA1199 binds Plexin A2 and protects from Semaphorin 3A-mediated cell death by promoting EGFR stability and signaling. Moreover, KIAA1199 is an EGFR-binding protein and KIAA1199 deficiency impairs EGF-dependent Src, MEK1 and ERK1/2 phosphorylations. Therefore, EGFR stability and signaling to downstream kinases requires KIAA1199. As such, KIAA1199 promotes EGF-mediated epithelial-mesenchymal transition (EMT). Taken together, our data define KIAA1199 as an oncogenic protein induced by HPV infection and constitutive NF-kB activity that transmits pro-survival and invasive signals through EGFR signaling. We used microarrays to detail the global programme of gene expression upon BCL-3 overexpression We used two experimental conditions, namely HaCat cells infected with a control lentivirus as well as HaCat cells infected with a BCL-3 expressing construct. Both experimental conditions were in triplicates.
Project description:The synthetic lethal association between BRCA deficiency and poly (ADP-ribose) polymerase (PARP) inhibition supports PARP inhibitor (PARPi) clinical efficacy in BRCA-mutated tumors. PARPis also demonstrate activity in non-BRCA mutated tumors presumably through induction of PARP1-DNA trapping. Despite pronounced clinical response, therapeutic resistance to PARPis inevitably develops. An abundance of knowledge has been built around resistance mechanisms in BRCA-mutated tumors, however, parallel understanding in non-BRCA mutated settings remains insufficient. In this study, we find a strong correlation between the epithelial-mesenchymal transition (EMT) signature and resistance to a clinical PARPi, Talazoparib, in non-BRCA mutated tumor cells. Genetic profiling demonstrates that SNAI2, a master EMT transcription factor, is transcriptionally induced by Talazoparib treatment or PARP1 depletion and this induction is partially responsible for the emerging resistance. Mechanistically, we find that the PARP1 protein directly binds to SNAI2 gene promoter and suppresses its transcription. Talazoparib treatment or PARP1 depletion lifts PARP1-mediated suppression and increases chromatin accessibility around SNAI2 promoters, thus driving SNAI2 transcription and drug resistance. We also find that depletion of the chromatin remodeler CHD1L suppresses SNAI2 expression and reverts acquired resistance to Talazoparib. The PARP1/CHD1L/SNAI2 transcription axis might be therapeutically targeted to re-sensitize Talazoparib in non-BRCA mutated tumors.
Project description:Analyses of the effect of CRISPR/CAS9 mediated knock out of the EMT-transcription factor SNAI2 on the mRNA expression profile of human neuroblastoma SH-SY5Y cells to identify genes that are differentially expressed upon loss of SNAI2. Results provide insight into genes that are repressed by SNAI2 in neuroblastoma cells under normal culture conditions, where loss of SNAI2 enhances the expression of genes involved in biological processes such as neuron development and neuron differentiation.
Project description:Rhabdomyosarcoma (RMS) is a pediatric malignancy of mesenchymal origin. Fusion Negative-RMS (FN-RMS) tumors are associated with RAS-pathway activation. RMS tumors express pro-differentiation myogenic transcription factors MYOD and MYOG, yet why they are unable to differentiate is poorly understood. Here we show that SNAI2 is highly expressed in FN-RMS, is regulated by MYOD and blocks myogenic differentiation promoting growth. Molecularly, SNAI2 preferentially binds E-Box-associated enhancer elements and represses expression by dampening enhancer function. SNAI2 inhibits MYOD at a subset of myogenic enhancers associated with terminal differentiation. Functional dissection demonstrates SNAI2 suppresses a MYOG, MEF2 and CDKN1A differentiation program. SNAI2 knockdown transcriptionally mimics a chemical blockade of the mutant RAS signal in FN-RMS, providing new insight connecting the genetic and epigenetic causes of this disease.