Project description:Malignant peripheral nerve sheath tumor (MPNST) is an aggressive sarcoma. Comprehensive proteomic profiles of 23 MPNST tumor specimens were obtained using LC-MS/MS. Among 23 tumor specimens, 13 patients showed favorable prognosis and 10 did local recurrence/distant metastasis.
Project description:Malignant peripheral nerve sheath tumors (MPNST) are aggressive cancers that occur spontaneously (sporadic MPNST) or from pre-existing, benign plexiform neurofibromas in neurofibromatosis type 1 (NF1) patients. MPNSTs metastasize easily, are resistant to therapeutic intervention and are frequently fatal. The molecular changes underlying the transition to malignancy in the NF1 setting are incompletely understood. Here we investigate the involvement of microRNAs in this process. Using an RT-PCR platform microRNA expression profiles were determined from a unique series of archival paired samples of plexiform neurofibroma and MPNST. At least 90 differentially expressed microRNAs (p<0.025; FDR<10%) were identified between the paired samples. Most microRNAs (91%) were found downregulated and 9% of the microRNAs were upregulated in MPNST. Based on the fold changes and statistical significance three downregulated microRNAs (let-7b-5p, miR-143-3p, miR-145-5p) and two upregulated microRNAs (miR135b-5p and miR-889-3p) were selected for further functional characterization. Their expression levels were validated in a relevant cell line panel and a series of unpaired fresh frozen tumor samples containing plexiform neurofibromas, atypical neurofibromas and MPNSTs. As part of the validation process we also determined and analyzed microRNA expression profiles of sporadic MPNSTs observing that microRNA expression discriminates NF1-associated and sporadic MPNSTs emphasizing their different etiologies. The involvement of microRNAs in tumorigenesis and cancer progression was examined in NF1-derived MPNST cell lines through modulating microRNA levels by transient transfection of microRNA mimics or inhibitors. The effects of microRNAs on cellular proliferation, migration, invasion and Wnt/ẞ-catenin signaling were determined. Our findings indicate that, some of the selected microRNAs affect migratory and invasive capabilities and Wnt signaling activity. It was observed that the functional effects upon microRNA modulation are distinct in different cell lines. From our study we conclude that miRNAs play essential regulatory roles in MPNST facilitating tumor progression.
Project description:We performed a genome-wide CRISPRi screen to identify potential contributors to radioresistance in the JH02.2 malignant peripheral nerve sheath tumor (MPNST) cell line.
Project description:We used single-cell RNA-sequencing (scRNA-seq) to study the effect of ionizing radiation on the transcriptomes of malignant peripheral nerve sheath tumors (MPNSTs) in vivo and in the context of the innate and adaptive immune response.
Project description:Malignant peripheral nerve sheath tumors (MPNSTs) are deadly sarcomas that lack effective therapies. In most MPNSTs, the retinoblastoma (RB1) tumor suppressor is disabled by hyperactivation of cyclin dependent kinases (CDKs), commonly through loss of CDK inhibitory proteins such as p27(Kip1). RABL6A is an inhibitor of RB1 whose role in MPNSTs is unknown. To gain insight into MPNST development and establish new treatment options, we investigated RABL6A-RB1 signaling and CDK inhibitor-based therapy in MPNSTs.
Project description:The clinical significance of specific genetic alterations, methylation signatures or microenvironmental composition in malignant peripheral nerve sheath tumors (MPNSTs) is unclear. We assembled an updated cohort of 30 patients with MPNSTs treated with surgical resection and postoperative radiation who underwent methylation profiling and detailed clinical follow-up. The data included in this submission include 7 of 30 samples, the remainder of which were submitted separately under GSE212963.