Project description:Based on the association of TP53 mutation and upregulated TP63 expression in the squamous subtype, we used cell lines derived from genetically engineered mouse models of PDAC (KRAS Trp53fl/+ and KRAS Trp53fl/+ Trp63fl/fl) to begin to unravel the functional consequences of these events in defining squamous tumours. RNA-Seq libraries were generated using TruSeq Stranded Total RNA (Part no. 15031048 Rev. D April 2013) kits, using on a Perkin ElmeraTMs Sciclone G3 NGS Workstation (Product no. SG3-31020-0300). Ribosomal depletion step was performed on 1 ug of total RNA using Ribo-Zero Gold prior to a heat fragmentation step aimed at producing libraries with an insert size between 120-200 bp. cDNA was then synthesized from the enriched and fragmented RNA using InvitrogenaTMs SuperScript II Reverse Transcriptase (Catalog no. 18064) and random primers. The resulting cDNA was further converted into double stranded DNA in the presence of dUTP to prevent subsequent amplification of the second strand and thus maintain the strandedness of the library. Following 3aTM adenylation and adaptor ligation libraries were subjected to 15 cycles of PCR to produce RNA-Seq libraries ready for sequencing. Prior to sequencing, exome and RNA-Seq libraries were qualified and quantified via CaliperaTMs LabChip GX (Part no. 122000) instrument using the DNA High Sensitivity Reagent kit (Product no. CLS760672). Quantification of libraries for clustering was performed using the KAPA Library Quantification Kits For Illumina sequencing platforms (Kit code KK4824) in combination with Life Technologies Viia 7 real time PCR instrument. All libraries were sequenced using the Illumina HiSeq 2000/2500 system with TruSeq SBS Kit v3 - HS.
Project description:In response to genotoxic stress the TP53 tumour suppressor activates target gene expression to induce cell cycle arrest or apoptosis depending on the extent of DNA damage. These canonical activities can be repressed by TP63 in normal stratifying epithelia to maintain proliferative capacity or drive proliferation of squamous cell carcinomas, where TP63 is frequently overexpressed/amplified. Here we use ChIP-sequencing, integrated with microarray analysis, to define the genome wide interplay between TP53 and TP63 in response to genotoxic stress in normal cells. We reveal that TP53 and TP63 bind to overlapping, but distinct cistromes of sites through utilization of distinctive consensus motifs and that TP53 is constitutively bound to a number of sites. We demonstrate that cisplatin and adriamycin elicit distinct effects on TP53 and TP63 binding events, through which TP53 can induce or repress transcription of an extensive network of genes by direct binding and/or modulation of TP63 activity. Collectively, this results in a global TP53 dependent repression of cell cycle progression, mitosis and DNA damage repair concomitant with activation of anti-proliferative and pro-apoptotic canonical target genes. Further analyses reveals that in the absence of genotoxic stress TP63 plays an important role in maintaining expression of DNA repair genes, loss of which results in defective repair Examination of p63 and p53 binding sites in neonatal foreskin keratinocytes in response to adriamycin or cisplatin treatment
Project description:In response to genotoxic stress the TP53 tumour suppressor activates target gene expression to induce cell cycle arrest or apoptosis depending on the extent of DNA damage. These canonical activities can be repressed by TP63 in normal stratifying epithelia to maintain proliferative capacity or drive proliferation of squamous cell carcinomas, where TP63 is frequently overexpressed/amplified. Here we use ChIP-sequencing, integrated with microarray analysis, to define the genome wide interplay between TP53 and TP63 in response to genotoxic stress in normal cells. We reveal that TP53 and TP63 bind to overlapping, but distinct cistromes of sites through utilization of distinctive consensus motifs and that TP53 is constitutively bound to a number of sites. We demonstrate that cisplatin and adriamycin elicit distinct effects on TP53 and TP63 binding events, through which TP53 can induce or repress transcription of an extensive network of genes by direct binding and/or modulation of TP63 activity. Collectively, this results in a global TP53 dependent repression of cell cycle progression, mitosis and DNA damage repair concomitant with activation of anti-proliferative and pro-apoptotic canonical target genes. Further analyses reveals that in the absence of genotoxic stress TP63 plays an important role in maintaining expression of DNA repair genes, loss of which results in defective repair Examination of gene expression levels of HFKS siRNA depleted for p53 or p63 in response to adriamycin or cisplatin treatment We analyzed RNA using the Affymetrix Human Exon 1.0 ST platform. Array data was processed using the AltAnalyze.
Project description:In response to genotoxic stress the TP53 tumour suppressor activates target gene expression to induce cell cycle arrest or apoptosis depending on the extent of DNA damage. These canonical activities can be repressed by TP63 in normal stratifying epithelia to maintain proliferative capacity or drive proliferation of squamous cell carcinomas, where TP63 is frequently overexpressed/amplified. Here we use ChIP-sequencing, integrated with microarray analysis, to define the genome wide interplay between TP53 and TP63 in response to genotoxic stress in normal cells. We reveal that TP53 and TP63 bind to overlapping, but distinct cistromes of sites through utilization of distinctive consensus motifs and that TP53 is constitutively bound to a number of sites. We demonstrate that cisplatin and adriamycin elicit distinct effects on TP53 and TP63 binding events, through which TP53 can induce or repress transcription of an extensive network of genes by direct binding and/or modulation of TP63 activity. Collectively, this results in a global TP53 dependent repression of cell cycle progression, mitosis and DNA damage repair concomitant with activation of anti-proliferative and pro-apoptotic canonical target genes. Further analyses reveals that in the absence of genotoxic stress TP63 plays an important role in maintaining expression of DNA repair genes, loss of which results in defective repair
Project description:In response to genotoxic stress the TP53 tumour suppressor activates target gene expression to induce cell cycle arrest or apoptosis depending on the extent of DNA damage. These canonical activities can be repressed by TP63 in normal stratifying epithelia to maintain proliferative capacity or drive proliferation of squamous cell carcinomas, where TP63 is frequently overexpressed/amplified. Here we use ChIP-sequencing, integrated with microarray analysis, to define the genome wide interplay between TP53 and TP63 in response to genotoxic stress in normal cells. We reveal that TP53 and TP63 bind to overlapping, but distinct cistromes of sites through utilization of distinctive consensus motifs and that TP53 is constitutively bound to a number of sites. We demonstrate that cisplatin and adriamycin elicit distinct effects on TP53 and TP63 binding events, through which TP53 can induce or repress transcription of an extensive network of genes by direct binding and/or modulation of TP63 activity. Collectively, this results in a global TP53 dependent repression of cell cycle progression, mitosis and DNA damage repair concomitant with activation of anti-proliferative and pro-apoptotic canonical target genes. Further analyses reveals that in the absence of genotoxic stress TP63 plays an important role in maintaining expression of DNA repair genes, loss of which results in defective repair Examination of gene expression levels of HFKS siRNA depleted for p53 or p63 in response to adriamycin or cisplatin treatment
Project description:The aberrant expression of squamous lineage markers in pancreatic ductal adenocarcinoma (PDA) has been correlated with poor clinical outcomes. However, the functional role of this putative trans-differentiation event in PDA pathogenesis remains unclear. Here, we show that expression of the transcription factor TP63 (ΔN isoform) is sufficient to install and sustain the enhancer landscape and transcriptional signature of the squamous lineage in human PDA cells. In addition, we demonstrate that TP63-driven enhancer reprogramming promotes aggressive tumor phenotypes, including enhanced cell motility and invasion and an accelerated growth of primary PDA tumors and metastases in vivo. Conversely, we provide evidence that squamous PDA remains addicted to TP63 to sustain the growth of primary tumors and metastases. Taken together, our study validates the functional significance of squamous trans-differentiation in PDA, and reveals TP63-based reprogramming of PDA cells as an experimental tool for investigating vulnerabilities linked to this cell fate transition.
Project description:The aberrant expression of squamous lineage markers in pancreatic ductal adenocarcinoma (PDA) has been correlated with poor clinical outcomes. However, the functional role of this putative trans-differentiation event in PDA pathogenesis remains unclear. Here, we show that expression of the transcription factor TP63 (ΔN isoform) is sufficient to install and sustain the enhancer landscape and transcriptional signature of the squamous lineage in human PDA cells. In addition, we demonstrate that TP63-driven enhancer reprogramming promotes aggressive tumor phenotypes, including enhanced cell motility and invasion and an accelerated growth of primary PDA tumors and metastases in vivo. Conversely, we provide evidence that squamous PDA remains addicted to TP63 to sustain the growth of primary tumors and metastases. Taken together, our study validates the functional significance of squamous trans-differentiation in PDA, and reveals TP63-based reprogramming of PDA cells as an experimental tool for investigating vulnerabilities linked to this cell fate transition.
Project description:The aberrant expression of squamous lineage markers in pancreatic ductal adenocarcinoma (PDA) has been correlated with poor clinical outcomes. However, the functional role of this putative trans-differentiation event in PDA pathogenesis remains unclear. Here, we show that expression of the transcription factor TP63 (ΔN isoform) is sufficient to install and sustain the enhancer landscape and transcriptional signature of the squamous lineage in human PDA cells. In addition, we demonstrate that TP63-driven enhancer reprogramming promotes aggressive tumor phenotypes, including enhanced cell motility and invasion and an accelerated growth of primary PDA tumors and metastases in vivo. Conversely, we provide evidence that squamous PDA remains addicted to TP63 to sustain the growth of primary tumors and metastases. Taken together, our study validates the functional significance of squamous trans-differentiation in PDA, and reveals TP63-based reprogramming of PDA cells as an experimental tool for investigating vulnerabilities linked to this cell fate transition.
Project description:TP53 and ARID1A are frequently mutated across cancer but rarely in the same primary tumor. Endometrial cancer has the highest TP53-ARID1A mutual exclusivity rate. However, the functional relationship between TP53 and ARID1A mutations in the endometrium has not been elucidated. We used genetically engineered mice and in vivo genomic approaches to discern both unique and overlapping roles of TP53 and ARID1A in the endometrium. TP53 loss with oncogenic PIK3CA*H1047R in the endometrial epithelium results in features of endometrial hyperplasia, adenocarcinoma, and intraepithelial carcinoma. Mutant endometrial epithelial cells were transcriptome profiled and compared to control cells and ARID1A/PIK3CA mutant endometrium. In the context of either TP53 or ARID1A loss, PIK3CA mutant endometrium exhibited inflammatory pathway activation, but other gene expression programs differed based on TP53 or ARID1A status, such as epithelial-to-mesenchymal transition. Gene expression patterns observed in the genetic mouse models are reflective of human tumors with each respective genetic alteration. Consistent with TP53-ARID1A mutual exclusivity, the p53 pathway is activated following ARID1A loss in the endometrial epithelium, where ARID1A normally directly represses p53 pathway genes in vivo, including the stress-inducible transcription factor, ATF3. However, co-existing TP53-ARID1A mutations led to invasive adenocarcinoma associated with mutant ARID1A-driven ATF3 induction, reduced apoptosis, TP63+ squamous differentiation and invasion. These data suggest TP53 and ARID1A mutations drive shared and distinct tumorigenic programs in the endometrium and promote invasive endometrial cancer when existing simultaneously. Hence, TP53 and ARID1A mutations may co-occur in a subset of aggressive or metastatic endometrial cancers, with ARID1A loss promoting squamous differentiation and the acquisition of invasive properties.
Project description:TP53 and ARID1A are frequently mutated across cancer but rarely in the same primary tumor. Endometrial cancer has the highest TP53-ARID1A mutual exclusivity rate. However, the functional relationship between TP53 and ARID1A mutations in the endometrium has not been elucidated. We used genetically engineered mice and in vivo genomic approaches to discern both unique and overlapping roles of TP53 and ARID1A in the endometrium. TP53 loss with oncogenic PIK3CA*H1047R in the endometrial epithelium results in features of endometrial hyperplasia, adenocarcinoma, and intraepithelial carcinoma. Mutant endometrial epithelial cells were transcriptome profiled and compared to control cells and ARID1A/PIK3CA mutant endometrium. In the context of either TP53 or ARID1A loss, PIK3CA mutant endometrium exhibited inflammatory pathway activation, but other gene expression programs differed based on TP53 or ARID1A status, such as epithelial-to-mesenchymal transition. Gene expression patterns observed in the genetic mouse models are reflective of human tumors with each respective genetic alteration. Consistent with TP53-ARID1A mutual exclusivity, the p53 pathway is activated following ARID1A loss in the endometrial epithelium, where ARID1A normally directly represses p53 pathway genes in vivo, including the stress-inducible transcription factor, ATF3. However, co-existing TP53-ARID1A mutations led to invasive adenocarcinoma associated with mutant ARID1A-driven ATF3 induction, reduced apoptosis, TP63+ squamous differentiation and invasion. These data suggest TP53 and ARID1A mutations drive shared and distinct tumorigenic programs in the endometrium and promote invasive endometrial cancer when existing simultaneously. Hence, TP53 and ARID1A mutations may co-occur in a subset of aggressive or metastatic endometrial cancers, with ARID1A loss promoting squamous differentiation and the acquisition of invasive properties.