Project description:Transcriptome analysis of mouse prostate cancer cell line (NPK) silenced for Nsd2 using shRNA or treated with MCTP--39. NPK prostatre cancer cells are derived Nkx3.1CreERT2/+ ;Ptenflox/flox;KrasLSL-G12D/+ mice, and were used to silence the histone methyltransferase NSD2 or treat them with the NSD2 inhibitor MCTP39 for subsequent gene expression profiling by RNAseq
Project description:NSD2 is a histone methyltransferase that specifically dimethylates histone H3 lysine 36 (H3K36me2), a modification associated with gene activation. Dramatic overexpression of NSD2 in t(4;14) multiple myeloma (MM) and an activating mutation of NSD2 discovered in acute lymphoblastic leukemia (ALL) are significantly associated with altered gene activation, transcription and DNA damage repair. The partner proteins through which NSD2 may influence critical cellular processes remain poorly defined. In this study, we utilized proximity-based labelling (BioID) combined with label-free quantitative mass spectrometry to identify high confidence NSD2 interacting partners in MM cells.
Project description:Androgen receptor (AR) is a ligand-responsive transcription factor that binds at enhancers to drive terminal differentiation of the prostatic luminal epithelia. By contrast, in tumors originating from these cells, AR chromatin occupancy is extensively reprogrammed to drive hyper-proliferative, metastatic, or therapy-resistant phenotypes, the molecular mechanisms of which remain poorly understood. Here we show that the tumor-specific enhancer circuitry of AR is critically reliant on the activity of Nuclear Receptor Binding SET Domain Protein 2 (NSD2), a histone 3 lysine 36 di-methyltransferase. NSD2 is ectopically expressed in prostate cancer cells and catalytic inhibition of NSD2 impairs AR trans-activation potential through partial off-loading from over 40,000 genomic sites or greater than 65% of its cistrome. The NSD2-dependent AR sites distinctly harbor a chimeric AR-half motif juxtaposed to a FOXA1 element. Similar chimeric motifs of AR are absent at the NSD2-independent AR enhancers and contain the canonical palindromic motifs instead. Meta-analyses of AR cistromes from patient tumors uncovered chimeric AR motifs to exclusively participate in tumor-specific enhancer circuitries, with a minimal role in physiological activity of AR. Accordingly, NSD2 inactivation attenuated hallmark cancer phenotypes that were fully reinstated upon exogenous NSD2 re-expression. Inactivation of NSD2 also engendered increased dependency on its paralog NSD1, which independently maintained AR and MYC hyper-transcriptional programs in cancer cells. Therapeutically exploiting these insights, we developed a dual NSD1/2 PROTAC degrader, called LLC0150, which was preferentially cytotoxic in AR-dependent prostate cancer and synergized with enzalutamide. In a pan-cancer screen, comprising over 120 cell lines from 22 distinct lineages, NSD1/2 co-degradation triggered apoptotic cell death in AR-addicted prostate cancer as well as NSD2-altered hematologic malignancies. Altogether, we identify NSD2 as a novel subunit of the AR neo-enhanceosome that wires prostate cancer gene expression programs, positioning NSD1/2 paralog co-targeting as a novel and potent therapeutic strategy.
Project description:Androgen receptor (AR) is a ligand-responsive transcription factor that binds at enhancers to drive terminal differentiation of the prostatic luminal epithelia. By contrast, in tumors originating from these cells, AR chromatin occupancy is extensively reprogrammed to drive hyper-proliferative, metastatic, or therapy-resistant phenotypes, the molecular mechanisms of which remain poorly understood. Here we show that the tumor-specific enhancer circuitry of AR is critically reliant on the activity of Nuclear Receptor Binding SET Domain Protein 2 (NSD2), a histone 3 lysine 36 di-methyltransferase. NSD2 is ectopically expressed in prostate cancer cells and catalytic inhibition of NSD2 impairs AR trans-activation potential through partial off-loading from over 40,000 genomic sites or greater than 65% of its cistrome. The NSD2-dependent AR sites distinctly harbor a chimeric AR-half motif juxtaposed to a FOXA1 element. Similar chimeric motifs of AR are absent at the NSD2-independent AR enhancers and contain the canonical palindromic motifs instead. Meta-analyses of AR cistromes from patient tumors uncovered chimeric AR motifs to exclusively participate in tumor-specific enhancer circuitries, with a minimal role in physiological activity of AR. Accordingly, NSD2 inactivation attenuated hallmark cancer phenotypes that were fully reinstated upon exogenous NSD2 re-expression. Inactivation of NSD2 also engendered increased dependency on its paralog NSD1, which independently maintained AR and MYC hyper-transcriptional programs in cancer cells. Therapeutically exploiting these insights, we developed a dual NSD1/2 PROTAC degrader, called LLC0150, which was preferentially cytotoxic in AR-dependent prostate cancer and synergized with enzalutamide. In a pan-cancer screen, comprising over 120 cell lines from 22 distinct lineages, NSD1/2 co-degradation triggered apoptotic cell death in AR-addicted prostate cancer as well as NSD2-altered hematologic malignancies. Altogether, we identify NSD2 as a novel subunit of the AR neo-enhanceosome that wires prostate cancer gene expression programs, positioning NSD1/2 paralog co-targeting as a novel and potent therapeutic strategy.
Project description:Metastasis is the key cause of failure of cancer therapy or mortality, but targeting metastatic seeding and colonization remains an unresolved challenge. Here, we report a novel molecular event in cancer metastasis mediated by NSD2/Rac1 signaling and provide a detailed mechanistic investigation of cancer metastasis. We found that NSD2, a histone methyltransferase responsible for di-methylating histone 3 at lysine 36, was overexpressed in metastatic tumors, and overexpressed NSD2 enhanced tumor metastasis both in vitro and in vivo. We further investigated that NSD2 promoted tumor metastasis by activating the Rac1 signaling pathway. Mechanistically, NSD2 methylated Tiam1, a guanine nucleotide exchange factor that facilitates GDP-Rac1 to GTP-Rac1 transition at K724. We demonstrated that Tiam1 K724 methylation plays a crucial role in Tiam1 activation and GDP-Rac1 to GTP-Rac1 transition. Specifically, we identified that Tiam1 K724 methylation could be a predictive factor in cancer prognosis, and we demonstrated that pharmacological blocking of Tiam1 K724 methylation by employing a transmembrane peptide inhibited tumor metastasis both in vitro and in vivo. Thus, NSD2-methylated Tiam1 promoted Rac1 signaling activation and cancer metastasis, which might provide novel insights into tumor metastasis inhibition.
Project description:Metastasis is the key cause of failure of cancer therapy or mortality, but targeting metastatic seeding and colonization remains an unresolved challenge. Here, we report a novel molecular event in cancer metastasis mediated by NSD2/Rac1 signaling and provide a detailed mechanistic investigation of cancer metastasis. We found that NSD2, a histone methyltransferase responsible for di-methylating histone 3 at lysine 36, was overexpressed in metastatic tumors, and overexpressed NSD2 enhanced tumor metastasis both in vitro and in vivo. We further investigated that NSD2 promoted tumor metastasis by activating the Rac1 signaling pathway. Mechanistically, NSD2 methylated Tiam1, a guanine nucleotide exchange factor that facilitates GDP-Rac1 to GTP-Rac1 transition at K724. We demonstrated that Tiam1 K724 methylation plays a crucial role in Tiam1 activation and GDP-Rac1 to GTP-Rac1 transition. Specifically, we identified that Tiam1 K724 methylation could be a predictive factor in cancer prognosis, and we demonstrated that pharmacological blocking of Tiam1 K724 methylation by employing a transmembrane peptide inhibited tumor metastasis both in vitro and in vivo. Thus, NSD2-methylated Tiam1 promoted Rac1 signaling activation and cancer metastasis, which might provide novel insights into tumor metastasis inhibition.