Project description:Estrogen Receptor alpha (ERα) is a key driver of most breast cancers, and it is the target of endocrine therapies used in the clinic to treat women with ERα positive (ER+) breast cancer. The two methods ChIP-seq (chromatin immunoprecipitation coupled with deep sequencing) and RIME (Rapid Immunoprecipitation of Endogenous Proteins) have greatly improved our understanding of ERα function during breast cancer progression and in response to anti-estrogens. A critical component of both ChIP-seq and RIME protocols is the antibody that is used to pull down the bait protein. To date, most of the ChIP-seq and RIME experiments for the study of ERα have been performed using the sc-543 antibody from Santa Cruz Biotechnology. However, this antibody has been discontinued, thereby severely impacting the study of ERα in normal physiology as well as diseases such as breast cancer and ovarian cancer. Here, we compare the sc-543 antibody with other commercially available antibodies, and we show that 06-935 (EMD Millipore) and ab3575 (Abcam) antibodies can successfully replace the sc-543 antibody for ChIP-seq and RIME experiments.
Project description:Chromatin immunoprecipitation (ChIP) has been a cornerstone for epigenetic analyses over the last decades, but even coupled to sequencing approaches (ChIP-seq), it is ultimately limited to one protein at a time. In a complementary effort, we here combined ChIP with label-free quantitative (LFQ) mass spectrometry (ChIP-MS) to interrogate local chromatin compositions. We demonstrate the versality of our approach at telomeres, with transcription factors, in tissue and by dCas9-driven locus-specific enrichment.
Project description:Chromatin immunoprecipitation (ChIP) has been a cornerstone for epigenetic analyses over the last decades, but even coupled to sequencing approaches (ChIP-seq), it is ultimately limited to one protein at a time. In a complementary effort, we here combined ChIP with label-free quantitative (LFQ) mass spectrometry (ChIP-MS) to interrogate local chromatin compositions. We demonstrate the versality of our approach at telomeres, with transcription factors, in tissue and by dCas9-driven locus-specific enrichment.
Project description:CHIP is a neuroprotective E3-ubiquitin ligase that supports longevity and healthy ageing. Loss of CHIP function has a major impact on life expectancy in animal models, whilst in humans’ mutations that compromise the E3-ligase activity of CHIP are causative for forms of Spinocerebellar Ataxia (SCA) that are accompanied by cognitive decline and/or dementia. The pathways regulated by CHIP to maintain neuronal health remain to be discovered. Gene-edited neuroblastoma cells were produced and used as a model to study the effects of CHIP loss on the steady state proteome in the absence of proteotoxic stress. Label free quantitative proteomic analysis (SWATH-MS) highlighted VGF, a member of the neuropeptide precursor family of proteins, as being a dominant protein responding to loss of CHIP function. By studying the dependence of VGF expression on CHIP using SILAC and RNA-Seq we have defined a role for the ligase in regulated neuropeptide expression.
Project description:The individualized treatment of tumors has always been an urgent problem in clinical practice. Organoids-on-a-chip can reflect the heterogeneity of tumors and is a good model for in vitro anticancer drug screening. In this study, surgical specimens of patients with advanced colorectal cancer will be collected for organoid culture and organoids-on-a- chip. Use organoids-on-a-chip to screen tumor chemotherapy drugs, compare the results of patients’ actual medication regimens, and study the guiding role of organoids in the formulation of precise tumor treatment plans. The investigators will compare the response of organoids to drugs in vitro with the patient’s response to actual chemotherapy and targeted drugs and explore the feasibility and accuracy of organoids-on-a-chip based drug screening for advanced colorectal cancer. The project will establish a screening platform for chemotherapeutic drugs and targeted drugs based on colorectal cancer organoids to quickly and accurately formulate personalized treatment plans for clinical patients.
Project description:In this study, we engineered a micro-well duct-on-chip platform to generate defined 3D aggregates from hiPSC-derived PPs and subsequently induce differentiation toward PDLOs. Time-resolved scRNA-seq combined with cleared immunofluorescence imaging provided a deep understanding of in vitro ductal cell type differentiation. By defining the emergent cell types at each stage of differentiation based on their gene expression profiles and organoid structures, we provide a precise cell-by-cell description of the in vitro differentiation trajectory. Transcriptional data of PDLOs were complemented by their proteome and secretome data, allowing the identification and validation of prognostic cancer marker. Thus, we show the applicability of hiPSC-derived PDLOs-on-chip for future ductal disease modeling.