Project description:Activating JAK and STAT mutations were discovered in many T-cell malignancies including ALK- anaplastic large cell lymphomas (ALCL). However, such mutations often occur in a minority of patients. To investigate the clinical application of targeting Janus Kinase (JAK) for ALK- ALCL, we treated ALK- cell lines of different histologic origins with JAK inhibitors. Interestingly, most exogenous cytokine independent cell lines responded to JAK inhibition regardless of JAK mutation status. JAK inhibitor sensitivity correlated with STAT3 phosphorylation status of tumor cells. Employing retroviral shRNA knockdown, we demonstrated that these JAK inhibitor sensitive cells were dependent on both JAK1 and STAT3 for survival. JAK1 and STAT3 gain-of-function mutations were found in some but not all JAK inhibitor sensitive cells. Moreover, the mutations alone could not explain the JAK1/STAT3 dependency as wild-type JAK1 or STAT3 was sufficient to promote cell survival in the cells that had either JAK1or STAT3 mutations. To investigate whether other mechanisms were involved, we knocked down upstream receptors GP130 or IL-2Rγ. Knockdown of GP130 or IL-2Rγ induced cell death in select JAK inhibitor sensitive cells. High levels of cytokine expression including IL-6 were demonstrated in cell lines as well as in primary ALK- ALCL tumors. Finally, ruxolitinib, a JAK1/2 inhibitor, was effective in vivo in a xenograft ALK- ALCL model. Our data suggest cytokine receptor signaling was required for tumor cell survival in diverse forms of ALK- ALCL even in the presence of JAK1/STAT3 mutations. Therefore, JAK-inhibitor therapy might benefit patients with ALK- ALCL that are pSTAT3+.
Project description:Anaplastic Large Cell Lymphoma (ALCL) is a clinical and biological heterogeneous disease including ALK positive and ALK negative systemic forms. To discover biomarkers and/or genes involved in ALK negative ALCL pathogenesis, we applied the Cancer Outlier Profile Analysis (COPA) algorithm to a gene expression profiling data set including 249 cases of T-NHLs and normal T-cells. Ectopic co-expression of ERBB4 and COL29A1 genes was detected in 24% of ALK negative ALCL patients. RNA sequencing and 5'RNA Ligase Mediated Rapid Amplification of cDNA Ends (RLM-RACE) identified two novel ERBB4 truncated transcripts, displaying intronic Transcription Starting Sites. ERBB4 expression was confirmed at protein level by western blotting and immunohistochemistry. Moreover, by luciferase assays we defined that the expression of ERBB4 aberrant transcripts is promoted by endogenous intronic Long Terminal Repeats (LTRs). In conclusion, we identified a new subclass of ALK negative ALCL characterized by aberrant expression of ERBB4 truncated transcripts carrying intronic 5'UTRs.
Project description:C/EBPβ (CCAAT enhancer binding protein) is a transcription factor that plays a crucial role in survival and transformation of ALK+ anaplastic large cell lymphoma (ALCL). The aim of this study was to identify the downstream targets of C/EBPβ responsible for ALK-mediated oncogenesis. C/EBPβ was knocked down in ALK+ ALCL cell lines with a C/EBPβ-shRNA, followed by gene expression profiling (GEP). GEP analysis revealed a reproducible signature of genes that were significantly regulated by C/EBPβ. Classification into biological categories revealed overrepresentation of genes involved in the immune response, apoptosis and cell proliferation. Transcriptional regulation by C/EBPβ was found in 6 of 11 (BCL2A1, G0S2, TRIB1, S100A9, DDX21 and DDIT4) genes investigated by chromatin immunoprecipitation. We demonstrated that BCL2A1, G0S2 and DDX21 play a crucial role in survival and proliferation of ALK+ ALCL cells. DDX21, a gene involved in rRNA biogenesis, was found differentially overexpressed in primary ALK+ ALCL cases. All three candidate genes were validated in primary ALCL cases by either immunohistochemistry or RT-qPCR. In conclusion, we identified and validated several key C/EBPβ-regulated genes with major impact on survival and cell growth in ALK+ ALCL, supporting the central role of C/EBPβ in ALK-mediated oncogenesis.
Project description:Deregulation of chromatin modifiers, including DNA helicases, are emerging as one of the mechanism underlying the transformation of anaplastic lymphoma kinase negative (ALK−) anaplastic large cell lymphoma (ALCL). We recently identified the DNA helicase HELLS as central for proficient ALK-ALCL proliferation and progression. By performing RNA-sequencing profiling coupled with bioinformatic prediction, we demonstrated that HELLS contributes to an appropriate cytokinesis via the transcriptional regulation of genes involved in cleavage furrow regulation in ALK- anaplastic large cell lymphoma
Project description:C/EBPβ (CCAAT enhancer binding protein) is a transcription factor that plays a crucial role in survival and transformation of ALK+ anaplastic large cell lymphoma (ALCL). The aim of this study was to identify the downstream targets of C/EBPβ responsible for ALK-mediated oncogenesis. C/EBPβ was knocked down in ALK+ ALCL cell lines with a C/EBPβ-shRNA, followed by gene expression profiling (GEP). GEP analysis revealed a reproducible signature of genes that were significantly regulated by C/EBPβ. Classification into biological categories revealed overrepresentation of genes involved in the immune response, apoptosis and cell proliferation. Transcriptional regulation by C/EBPβ was found in 6 of 11 (BCL2A1, G0S2, TRIB1, S100A9, DDX21 and DDIT4) genes investigated by chromatin immunoprecipitation. We demonstrated that BCL2A1, G0S2 and DDX21 play a crucial role in survival and proliferation of ALK+ ALCL cells. DDX21, a gene involved in rRNA biogenesis, was found differentially overexpressed in primary ALK+ ALCL cases. All three candidate genes were validated in primary ALCL cases by either immunohistochemistry or RT-qPCR. In conclusion, we identified and validated several key C/EBPβ-regulated genes with major impact on survival and cell growth in ALK+ ALCL, supporting the central role of C/EBPβ in ALK-mediated oncogenesis. Kijk and SUDHL1 cell lines transfected with shRNA for C/EBPbeta were compared to control cells (3 biological replicates per group) and untreated cells (1 biological replicate)
Project description:A "Cartes d'Identite des Tumeurs" (CIT) project from the french Ligue Nationale Contre le Cancer (http://cit.ligue-cancer.net). Affymetrix UU133A gene expression data for a series of 32 cases of systemic Anaplastic Large Cell Lymphoma<br> (ALCL) and 5 ALCL cell lines; used to (1) confirm that tumors expressing Anaplastic Lymphoma Kinase (ALK+ ALCL) and ALK- ALCLs are different entities, (2) identify most significantly differentially expressed genes between ALK+ and ALK- samples, (3) generate a molecular signature of ALK- ALCL, (4) perform unsupervised analysis classifying ALCL in sub-groups related to morphology and clinical variables (e.g. disease stage and enrichment with 'early relapse' patients).<br> <br> Principal Investigator: Dr Georges DELSOL-- Centre de Physiopathologie Toulouse-Purpan CHU-Purpan -- Toulouse -- France -- Email: delsol.g@chu-toulouse.fr <br> Programme "Cartes d'identite des Tumeurs" (CIT) of the "Ligue Nationale Contre le Cancer" (LNCC)<br> Submitter: Fabien PETEL (petelf@ligue-cancer.net)
Project description:Anaplastic large cell lymphoma (ALCL) is a peripheral T-cell lymphoma that accounts for 10–15% of all childhood lymphomas. Despite the observation that more than 90% of the cases show ALK-rearrangement resulting in aberrant ALK kinase expression, there is significant clinical, morphologic, and biological heterogeneity. To gain insight into the molecular heterogeneity within ALK-positive ALCL, we analyzed 46 ALK-positive ALCL samples by whole-exome sequencing, RNA-sequencing, and DNA methylation array analysis. Gene expression and methylation profiling consistently subclassified ALK-positive ALCL cases into two groups differentiated by ALK expression level. The ALK-low group showed enrichment pathways of the immune response and cytokine signaling and were more heavily hypermethylated than the ALK high group, which was characterized by enriched pathways of cell growth, proliferation, metabolic pathways, and large copy number change. Taken together, these findings suggest that there is molecular heterogeneity within pediatric ALK+ALCL, predicting distinct biological mechanisms that may be utilized as prognostic markers.
Project description:We used a CRISPR-Cas9-based genome-wide guide RNA (sgRNA) library to identify genes responsible for driving drug resistance in ALK+ ALCL cells under crizotinib treatment.We screened 4 diffrerent ALK+ ALCL cell lines, TS, SU-DHL1, COST and KARPAS299. Every cell line was transduced with GeCKO A and GeCKO B sgRNA libraries separately. After puromycin selection, cells were splitted into 3 groups: Day 0 (baseline time point), crizotinib treated group (treated for 14 days) and DMSO treated group (treated for 14 days). TS and SU-DHL1 cells were treated with 40nM criztonib for 14 days and at the end of this period crizotinib concentration was increased to 80nM. COST cells received 50nM crizotinib for 14 days. KARPAS299 cells first received 50nM crizotinib for 14 days and at the end of this period crizotinib concentration was increased to 100nM. Crizotinib concentrations were determined based on their sensitivity for crizotinib for each cell line. The screening was repeated twice for TS and SU-DHL1 ALK+ ALCL cells. DNA isolotation was performed from all groups and each sgRNA sequence served as a barcode for Next Generation Illumina-based DNA sequencing. We compared enriched sgRNA sequences between Day 0 and DMSO conditions. We found that while PTPN2 was a top hit for all 4 ALK+ ALCL cells, PTPN1 was a top hit for TS and SU-DHL1 cells. We subsequently validated roles of PTPN1 and PTPN2 in crizotinib resistance separately. We demonstrated that both PTPN1 and PTPN2 can drive crizotinib resistance in ALK+ ALCL cells. In this study, we found two phosphatases, PTPN1 and PTPN2, involved in drug resitance in ALK+ ALCL using a CRSIPR Cas9-based screening approach. These two phosphatases regulate ALK phospharylation and therefore affect downstream signalling pathways involved in tumor growth and proliferation.
Project description:Anaplastic large-cell lymphoma (ALCL) makes up approximately 15% of paediatric non-Hodgkin's lymphomas of childhood. The vast majority of them is associated with the t(2;5)(p23;q35) translocation that results in the expression of a hybrid oncogenic tyrosine kinase, NPM-ALK. In order to investigate ALCL biological characteristics we used transcriptional profiling approach. Genome-wide gene expression profiling, performed on 23 paediatric ALCL and 12 reactive lymph nodes specimens, showed two novel ALCL subgroups based on their NPM-ALK expression levels (named (ALK low and ALK high). Gene set enrichment analysis revealed, in ALK low samples, a positive enrichment of genes involved in the Interleukin signaling pathway, whereas we found increased expression of genes related to cell cycle progression and division in ALK high tumour samples, such as Aurora Kinase A (AURKA) and B (AURKB). Growth inhibition was observed upon administration of AURKA and AURKB inhibitors Alisertib and Barasertib and it was associated with perturbation of the cell cycle and induction of apoptosis. In conclusion we identified two novel ALCL subgroups, which display unique biological characteristics suggesting sensitivity to distinct targeted therapies.