Project description:Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a heterogeneous group of malignancies with poor outcome. Here we identified a subgroup, PTCL-NOS SMARCB1-, which is characterized by the lack of SMARCB1 protein expression and is more common in young patients under 25 years of age. To investigate the cellular heterogeneity of PTCL-NOS SMARCB1- and the role of its tumor microenvironment, we performed single-nuclei RNA sequencing (snRNA-seq) of five patient samples.
Project description:Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) are aggressive and heterogeneous tumors with poor outcome and scarce genetic characterization. We analyzed by immunohistochemistry tumor tissue of adult and pediatric PTCL-NOS patients and discovered frequent loss of SMARCB1 positivity, mostly associated with pediatric cases (45%). Using a genetically engineered mouse model (PTCL-NOSSmarcb1-) and single-cell RNA sequencing, we investigated the transcriptional landscape of this Smarcb1-negative PTCL-NOS tumor and the functional interactions between tumor and tumor microenvironment (TME). We unrevealed an immunosuppressive, exhausted and proinflammatory TME, characterized by high myeloid cell infiltration (predominantly myeloid derived suppressor cells, MDSC) and reduced lymphoid infiltration. In addition, using a multidrug epigenetic screen in vitro, we identified histone deacetylase inhibitors (HDACi) as promising agents against PTCL-NOSSmarcb1-. Treatment of PTCL-NOSSmarcb1- mice with SAHA, a pan-HDACi, triggered TME remodelling, promoting the replenishment of T- and B-cell compartments and the limitation/reversion of the exhaustion phenotype. In conclusion, we have identified a novel PTCL-NOS subtype characterized by the loss of SMARCB1 at pediatric ages, presenting an exhausted and immunosuppressive TME. Administration of SAHA reshaped the TME increasing lymphoid cells recruitment into the tumor bed, turning the tumor from cold to hot. These results provide the rationale for further investigations based on combination therapies.
Project description:Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) are aggressive and heterogeneous tumors with poor outcome and scarce genetic characterization. We analyzed by immunohistochemistry tumor tissue of adult and pediatric PTCL-NOS patients and discovered frequent loss of SMARCB1 positivity, mostly associated with pediatric cases (45%). Using a genetically engineered mouse model (PTCL-NOSSmarcb1-) and single-cell RNA sequencing, we investigated the transcriptional landscape of this Smarcb1-negative PTCL-NOS tumor and the functional interactions between tumor and tumor microenvironment (TME). We unrevealed an immunosuppressive, exhausted and proinflammatory TME, characterized by high myeloid cell infiltration (predominantly myeloid derived suppressor cells, MDSC) and reduced lymphoid infiltration. In addition, using a multidrug epigenetic screen in vitro, we identified histone deacetylase inhibitors (HDACi) as promising agents against PTCL-NOSSmarcb1-. Treatment of PTCL-NOSSmarcb1- mice with SAHA, a pan-HDACi, triggered TME remodelling, promoting the replenishment of T- and B-cell compartments and the limitation/reversion of the exhaustion phenotype. In conclusion, we have identified a novel PTCL-NOS subtype characterized by the loss of SMARCB1 at pediatric ages, presenting an exhausted and immunosuppressive TME. Administration of SAHA reshaped the TME increasing lymphoid cells recruitment into the tumor bed, turning the tumor from cold to hot. These results provide the rationale for further investigations based on combination therapies.
Project description:Peripheral T-cell lymphomas (PTCLs) are heterogenous T-cell neoplasms often associated with epigenetic dysregulation. We investigated de novo DNA methyltransferase 3A (DNMT3A) mutations in common PTCL entities, including angioimmunoblastic T-cell lymphoma and novel molecular subtypes identified within PTCL-not otherwise specified (PTCL-NOS) designated as PTCL-GATA3 and PTCL-TBX21. DNMT3A-mutated PTCL-TBX21 cases showed inferior overall-survival, with DNMT3A mutated residues skewed towards the methyltransferase domain and dimerization motif (S881–R887). Transcriptional profiling demonstrated significant enrichment of activated CD8+ T-cell cytotoxic gene signatures in the DNMT3A-mutant PTCL-TBX21 cases, which was further validated using immunohistochemistry. Genome-wide methylation analysis of DNMT3A-mutant versus wild-type PTCL-TBX21 cases demonstrated hypomethylation in target genes regulating IFN-g, TCR signaling and EOMES, a master transcriptional regulator of cytotoxic effector cells. Similar findings were observed in a murine model of PTCL with Dnmt3a loss (in-vivo) and further validated in-vitro by ectopic expression of DNMT3A-mutants (DNMT3A-R882, -Q886, -V716, versus WT) in CD8+T-cell line, resulting in T-cell activation and EOMES upregulation. Furthermore, stable, ectopic expression of the DNMT3A-mutants in primary CD3+ T-cell cultures resulted in the preferential outgrowth of CD8+ T-cells with DNMT3AR882H mutation. Single-cell-RNA-seq analysis of CD3+ T-cells revealed differential CD8+ T-cell subset polarization, mirroring findings in DNMT3A-mutated PTCL-TBX21 and validating the cytotoxic and T-cell memory transcriptional programs associated with the DNMT3AR882H mutation. Our findings indicate that DNMT3A mutations define a cytotoxic subset in PTCL-TBX21 with prognostic significance, thus may further refine pathological heterogeneity in PTCL-NOS and suggest alternative treatment strategies for this subset.
Project description:Peripheral T-cell lymphomas (PTCLs) are heterogenous T-cell neoplasms often associated with epigenetic dysregulation. We investigated de novo DNA methyltransferase 3A (DNMT3A) mutations in common PTCL entities, including angioimmunoblastic T-cell lymphoma and novel molecular subtypes identified within PTCL-not otherwise specified (PTCL-NOS) designated as PTCL-GATA3 and PTCL-TBX21. DNMT3A-mutated PTCL-TBX21 cases showed inferior overall-survival, with DNMT3A mutated residues skewed towards the methyltransferase domain and dimerization motif (S881–R887). Transcriptional profiling demonstrated significant enrichment of activated CD8+ T-cell cytotoxic gene signatures in the DNMT3A-mutant PTCL-TBX21 cases, which was further validated using immunohistochemistry. Genome-wide methylation analysis of DNMT3A-mutant versus wild-type PTCL-TBX21 cases demonstrated hypomethylation in target genes regulating IFN-g, TCR signaling and EOMES, a master transcriptional regulator of cytotoxic effector cells. Similar findings were observed in a murine model of PTCL with Dnmt3a loss (in-vivo) and further validated in-vitro by ectopic expression of DNMT3A-mutants (DNMT3A-R882, -Q886, -V716, versus WT) in CD8+T-cell line, resulting in T-cell activation and EOMES upregulation. Furthermore, stable, ectopic expression of the DNMT3A-mutants in primary CD3+ T-cell cultures resulted in the preferential outgrowth of CD8+ T-cells with DNMT3AR882H mutation. Single-cell-RNA-seq analysis of CD3+ T-cells revealed differential CD8+ T-cell subset polarization, mirroring findings in DNMT3A-mutated PTCL-TBX21 and validating the cytotoxic and T-cell memory transcriptional programs associated with the DNMT3AR882H mutation. Our findings indicate that DNMT3A mutations define a cytotoxic subset in PTCL-TBX21 with prognostic significance, thus may further refine pathological heterogeneity in PTCL-NOS and suggest alternative treatment strategies for this subset.
Project description:This dataset contains single cell RNA-seq data of stromal cells derived from two PDX models (N = 2 in total) and bulk RNA-seq data of two PDX models treated with gemcitabine and our novel antibody-drug conjugate, C6-EBET (N = 59 in total). Bulk RNA-seq experiments were performed with Agilent SureSelect Strand Specific RNA Library Prep Kit (Agilent). Single cell RNA-seq experiments were performed with Chromium Single Cell 3' Reagent Kits v2 Chemistry (10x Genomics).
Project description:Proteogenomics informed by RNA-seq derived database of Dreissena polymorpha animals exposed to carbamazepine and methyl-mercury (single and co-exposures