Project description:Glioblastoma stem cells (GSCs) are thought to be the source of tumor growth and therapy resistance. Core biosies that are used to generate GSC cultures are ususally taken from one part of the tumor and are thus unlikely to represent intra-tumoral heterogeneity. This study shows that the ultrasonic aspirates (UA), that are usually considered as a biological waste, can be used as a reliable source of GSCs. Furthermore the UA aspirates seem to be capturing the tumorigenic signature better than the traditional biopsies.
Project description:Adult neural progenitor cells (aNPCs) are a potential source for cell based therapy for neurodegenerative diseases and traumatic brain injuries. We show that the ultrasonic aspirate samples that are typically considered as a waste after surgery are a great source for aHNPCs.
Project description:Robust and reliable and in vitro models are essential in the discovery of new treatment options for high-grade glioma (HGG), however, establishing successful patient-derived cell cultures has posed significant challenges. We established glioma stem-like cell (GSC) cultures from 114 consecutive HGG specimens, obtained via traditional surgical resection and/or ultrasonic aspiration, using fully-dissociated single cells (single cell-derived, SCD) and partially dissociated tissue fragments (3D-derived, 3DD). Copy number profiling assessed genetic similarities, while single-cell RNA sequencing evaluated transcriptomic heterogeneity. Proof-of-concept personalized drug screening was performed using a panel of approved anti-cancer agents. Higher success rates in establishing GSC cultures were obtained from ultrasonic aspirates (SCD and 3DD) and 3DD surgical samples compared to SCD cultures from surgical samples. Combining these approaches in parallel yielded a 96% success rate. In rare cases, copy number variations in original tumor tissue were lost in culture, leading to discernible changes in cell morphology. Single-cell sequencing revealed greater heterogeneity of transcriptomic clusters in ultrasonic aspiration-derived cultures compared to resection-derived cultures. Our study's protocol supported the screening of 20 anti-cancer agents within a clinically-relevant timeframe in 16 of 18 consecutive HGG samples. Our optimized protocol therefore provides a reliable tool for generating HGG cell cultures which capture the tumors’ molecular characteristics and supports precision medicine applications.
Project description:Robust and reliable and in vitro models are essential in the discovery of new treatment options for high-grade glioma (HGG), however, establishing successful patient-derived cell cultures has posed significant challenges. We established glioma stem-like cell (GSC) cultures from 114 consecutive HGG specimens, obtained via traditional surgical resection and/or ultrasonic aspiration, using fully-dissociated single cells (single cell-derived, SCD) and partially dissociated tissue fragments (3D-derived, 3DD). Copy number profiling assessed genetic similarities, while single-cell RNA sequencing evaluated transcriptomic heterogeneity. Proof-of-concept personalized drug screening was performed using a panel of approved anti-cancer agents. Higher success rates in establishing GSC cultures were obtained from ultrasonic aspirates (SCD and 3DD) and 3DD surgical samples compared to SCD cultures from surgical samples. Combining these approaches in parallel yielded a 96% success rate. In rare cases, copy number variations in original tumor tissue were lost in culture, leading to discernible changes in cell morphology. Single-cell sequencing revealed greater heterogeneity of transcriptomic clusters in ultrasonic aspiration-derived cultures compared to resection-derived cultures. Our study's protocol supported the screening of 20 anti-cancer agents within a clinically-relevant timeframe in 16 of 18 consecutive HGG samples. Our optimized protocol therefore provides a reliable tool for generating HGG cell cultures which capture the tumors’ molecular characteristics and supports precision medicine applications.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs. One-condition experment, gene expression of 3A6
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.