Similar Datasets
Project description:The therapeutic landscape of melanoma is rapidly changing. While targeted inhibitors yield significant responses, their clinical benefit is often limited by the early onset of drug resistance. This motivates the pursuit to establish more durable clinical responses, by developing combinatorial therapies. But while potential new combinatorial targets steadily increase in numbers, they cannot possibly all be tested in patients. Similarly, while genetically engineered mouse melanoma models have great merit, they do not capture the enormous genetic diversity and heterogeneity typical in human melanoma. Furthermore, whereas in vitro studies have many advantages, they lack the presence of micro-environmental factors, which can have a profound impact on tumor progression and therapy response. This prompted us to develop an in vivo model for human melanoma that allows for studying the dynamics of tumor progression and drug response, with concurrent evaluation and optimization of new treatment regimens. Here, we present a collection of patient-derived xenografts (PDX), derived from BRAFV600E, NRASQ61 or BRAFWT/NRASWT melanoma metastases. The BRAFV600E PDX melanomas were acquired both prior to treatment with the BRAF inhibitor vemurafenib and after resistance had occurred, including six matched pairs. We find that PDX resemble their human donors’ melanomas regarding biomarkers, chromosomal aberrations, RNA expression profiles, mutational spectrum and targeted drug resistance patterns. Mutations, previously identified to cause resistance to BRAF inhibitors, are captured in PDX derived from resistant melanomThis melanoma PDX platform represents a comprehensive public resource to study both fundamental and translational aspects of melanoma progression and treatment in a physiologically relevant setting.
2016-05-27 | GSE73737 | GEO
Project description:Tumour cells adapt to nutrient deprivation in vivo, yet strategies targeting the nutrient poor microenvironment remain unexplored. We recently found, in melanoma, tumour cells often experience low glutamine levels, which induce histone hypermethylation, promote dedifferentiation, and increase resistance to BRAF inhibitors. These findings raise the possibility that increased glutamine levels can be detrimental to melanoma tumours. Here, we show that dietary glutamine supplementation significantly inhibits melanoma tumour growth, prolongs survival in transgenic mouse model, and increases sensitivity to BRAF targeted inhibitors in both melanoma xenograft and patient-derived xenograft (PDX) models. Notably, metabolomic analysis reveals that dietary uptake of glutamine effectively increases the concentration of glutamine and its downstream metabolite, αKG, in serum and tumours, without increasing biosynthetic intermediates necessary for cell proliferation. Mechanistically, we find that glutamine supplementation uniformly alters the transcriptome and suppresses expression of many melanoma-associated genes. Our data further demonstrate that increase in intra-tumoural αKG concentration, following glutamine supplementation, drives hypomethylation of H3K4me3, thereby suppressing epigenetically-activated oncogenic pathways in melanoma. Therefore, our findings provide important evidence that glutamine supplementation can serve as a potential dietary intervention to block melanoma tumour growth and sensitize tumours to targeted therapy via epigenetic reprogramming.
2020-05-14 | GSE140274 | GEO
Project description:mRNA expression profiling of pancreatic cancer, comparing adjacent normal tissue, patient tumour and first generation patient derived xenograft tumours Fresh tumour samples for human pancreatic adenocarcinoma patients were implanted in SCID mice. 70% of these pancreatic ductal adenocarcinoma patients grew as PDX tumours, confirmed by histopathology. Frozen samples from F1 PDX tumours could be later successful passaged in SCID mice to F2 PDX tumours. The human origin of the PDX was confirmed using human specific antibodies; however, the stromal component was replaced by murine cells. Cell lines were successfully developed from three PDX tumours. RNA was extracted from 8 PDX tumours and where possible, corresponding primary tumour and adjacent normal tissues. mRNA profiles of tumour vs F1 PDX and normal vs tumour were compared by Affymetric microarray analysis
2023-03-06 | GSE207345 | GEO
Project description:Purpose: Study the changes in the transcriptome of metastatic melanoma PDX cells upon combination treatment with AURKA and MEK inhibitors Methods: RNAseq analysis of melanoma PDX cells treated with AURKA inhibitor Alisertib (500nM) and MEK inhibitor trametinib (100nM) for 72 h
2023-07-07 | GSE207645 | GEO
Project description:Purpose: Study of transcriptomic changes upon depletion of USP7 Methods: Melanoma PDX cells were transduced with lentiviral vectors expressing Scrambled(shSCR) or USP7 targeting (shUSP7) shRNA
2022-08-24 | GSE180986 | GEO
Project description:The BCBC Promoter Chip 5B was used to identify genomic targets of Pdx-1 binding. Genomic DNA from mouse NIT-1 insulinoma cells was immunoprecipitated with a Pdx-1 Antibody, PCR amplified, and labeled to the chip. All hybridizations were versus a common reference sample which was a labeled IgG IP. Additionally a Pdx1 SACO library for NIT-1 cells was generated.
2014-11-21 | E-MTAB-3126 | biostudies-arrayexpress
Project description:Patient-derived xenograft platform for metastatic melanoma: RNA sequencing of 95 melanoma PDX samples
| PRJNA530201 | ENA
Project description:Although high clinical response rates are seen for immune checkpoint blockade (ICB) of metastatic melanoma, both intrinsic and acquired ICB resistance remain formidable challenges. Combination ICB shows improved clinical benefit, but is associated with severe adverse events and exceedingly high cost. Therefore, there is a dire need to stratify individual patients for their likelihood of responding to either anti-PD-1 or anti-CTLA-4 monotherapy, or the combination. Since it is conceivable that ICB responses are influenced by both tumor cell-intrinsic and stromal factors, we hypothesized that a predictive classifier ought to mirror both of these distinct features. We used a panel of melanoma patient-derived xenografts (PDX), in which human stromal cells upon transplantation are naturally replaced by their murine counterparts, to computationally subtract PDX RNA expression signals from those in patients’ melanomas. We thus derived both “Stromal immune” (SIM) and tumor cell-specific “Tumor-autonomous inflammation” (TAF) signatures. Here we report that the SIM signature predicts response to anti-CTLA-4 but not anti-PD-1 treatment, whereas the tumor TAF signature predicts response to anti-PD-1 but not anti-CTLA-4. Moreover, when used in conjunction, the signatures accurately predict response in two independent patient cohorts treated with the anti-CTLA-4 + anti-PD-1 combination. These signatures may be clinically exploited for personalized treatment advice based on the predicted benefit from either anti-CTLA-4 or anti-PD-1 monotherapy or their combination.
2020-04-27 | GSE129127 | GEO