Cell-selective telomere damage by thiopurine-based oligonucleotide for diffuse large B cell lymphoma immunotherapy.

Telomerase (TERT) is an enzyme involved in maintaining telomere length in diffuse large B cell lymphoma (DLBCL). Previous attempts to target TERT cancers faced challenges, including the delayed clinical responses and on-target/off-tumor toxicities. Here, we present a DLBCL-targeted oligonucleotide designed to deliver a synthetic TERT substrate, 6-thio-2'-deoxy-guanosine (6tdG), damaging telomeres and triggering apoptosis.

Endothelial AGO1 Drives Vascular Inflammation and Atherosclerosis via a Non-Canonical Nuclear Mechanism.

Background: Endothelial cell (EC) dysfunction is both a cause and consequence of vascular inflammation and lipid dysregulation in atherosclerosis, yet the molecular drivers linking EC dysfunction to systemic metabolic derangements remain incompletely understood. We previously identified Argonaute 1 (AGO1)-a canonical component of the RNA-induced silencing complex-as a regulator of EC function in angiogenesis and metabolism. In this study, we uncover a previously unrecognized, non-canonical role of nuclear AGO1 in ECs as a transcriptional coactivator of NF-κB, and demonstrate that EC-specific AGO1 inhibition simultaneously improves lipid metabolism, liver function, and vascular inflammation, thereby attenuating atherosclerosis.

Multimodal glioma immunotherapy combining TLR9-targeted STAT3 antisense oligodeoxynucleotides with PD1 immune checkpoint blockade.

Background: Therapeutic resistance in glioblastoma (GBM) is multifactorial and results from genetic heterogeneity, the immunoprivileged localization and the potently tolerogenic microenvironment. Signal transducer and activator of transcription 3 (STAT3) plays a key role in both glioma cell survival and immune evasion reinforcing GBM resistance.

Methods: Here, we describe a new cell-selective and double-stranded STAT3 antisense oligonucleotide (CpG-STAT3dsASO) for targeting human/mouse glioma cells and GAMs but not T-cells.

New Transferrin Receptor-Targeting Conjugate Effectively Delivers DNA to Mouse Brain.

Delivery across the blood-brain barrier (BBB) is one of the most challenging tasks for modern biopharmaceutics. Many attempts have been taken, with only low delivery efficacies achieved so far. We report a new transferrin receptor-targeting (TfR) RNA aptamer conjugated to DSPE lipid that leads to an unprecedented effective uptake in the brain, with brain-to-serum ratios up to 6.

miR-142 deficit in T cells during blast crisis promotes chronic myeloid leukemia immune escape.

We reported that an acquired miR-142 deficit transforms chronic phase (CP) chronic myeloid leukemia (CML) leukemic stem cells (LSCs) into blast crisis (BC) LSCs. Given the role of miR-142 in the development and activity of the immune system, we postulated that this deficit also promotes LSC immune escape. Herein, we report on IL-6-driven miR-142 deficit occurring in T cells during BC transformation.

Local CpG- siRNA treatment improves antitumor effects of immune checkpoint inhibitors.

Immune checkpoint blockade (ICB) therapy has significantly benefited patients with several types of solid tumors and some lymphomas. However, many of the treated patients do not have a durable clinical response. It has been demonstrated that rescuing exhausted CD8 T cells is required for ICB-mediated antitumor effects.

A platform to deliver single and bi-specific Cas9/guide RNA to perturb genes in vitro and in vivo.

Although CRISPR-Cas9 technology is poised to revolutionize the treatment of diseases with underlying genetic mutations, it faces some significant issues limiting clinical entry. They include low-efficiency in vivo systemic delivery and undesired off-target effects. Here, we demonstrate, by modifying Cas9 with phosphorothioate-DNA oligos (PSs), that one can efficiently deliver single and bi-specific CRISPR-Cas9/guide RNA (gRNA) dimers in vitro and in vivo with reduced off-target effects.

Oligo-PROTAC strategy for cell-selective and targeted degradation of activated STAT3.

Decoy oligodeoxynucleotides (ODNs) allow targeting undruggable transcription factors, such as STAT3, but their limited potency and lack of delivery methods hampered translation. To overcome these challenges, we conjugated a STAT3-specific decoy to thalidomide, a ligand to cereblon in E3 ubiquitin ligase complex, to generate a proteolysis-targeting chimera (STAT3D). STAT3D downregulated STAT3 in target cells, but not STAT1 or STAT5.

Acquired miR-142 deficit in leukemic stem cells suffices to drive chronic myeloid leukemia into blast crisis.

The mechanisms underlying the transformation of chronic myeloid leukemia (CML) from chronic phase (CP) to blast crisis (BC) are not fully elucidated. Here, we show lower levels of miR-142 in CD34CD38 blasts from BC CML patients than in those from CP CML patients, suggesting that miR-142 deficit is implicated in BC evolution. Thus, we create miR-142 knockout CML (i.

Local CpG- siRNA treatment improves antitumor effects of immune checkpoint inhibitors.

Immune checkpoint blockade (ICB) therapy has significantly benefited patients with several types of solid tumors and some lymphomas. However, many of the treated patients do not have durable clinical response. It has been demonstrated that rescuing exhausted CD8 T cells is required for ICB-mediated antitumor effects.

Targeted systematic evolution of an RNA platform neutralizing DNMT1 function and controlling DNA methylation.

DNA methylation is a fundamental epigenetic modification regulating gene expression. Aberrant DNA methylation is the most common molecular lesion in cancer cells. However, medical intervention has been limited to the use of broadly acting, small molecule-based demethylating drugs with significant side-effects and toxicities.

Enhancing SIRT1 Gene Expression Using Small Activating RNAs: A Novel Approach for Reversing Metabolic Syndrome.

Metabolic syndrome (MetS) is a pathological condition characterized by abdominal obesity, insulin resistance, hypertension, and hyperlipidemia. Sirtuin 1 (SIRT1), a highly conserved histone deacetylase, is characterized as a key metabolic regulator and protector against aging-associated pathologies, including MetS. In this study, we investigate the therapeutic potential of activating SIRT1 using small activating RNAs (saRNA), thereby reducing inflammatory-like responses and re-establishing normal lipid metabolism.

Glioma-targeted delivery of exosome-encapsulated antisense oligonucleotides using neural stem cells.

Tropism of neural stem cells (NSCs) to hypoxic tumor areas provides an opportunity for the drug delivery. Here, we demonstrate that NSCs effectively transport antisense oligonucleotides (ASOs) targeting oncogenic and tolerogenic signal transducer and activator of transcription 3 (STAT3) protein into glioma microenvironment. To enable spontaneous, scavenger receptor-mediated endocytosis by NSCs, we used previously described CpG-STAT3ASO conjugates.

T-cell surface generation of dual bivalent, bispecific T-cell engaging, RNA duplex cross-linked antibodies (dbBiTERs) for re-directed tumor cell lysis.

Background: Genetic engineered Bispecific T-cell engagers (BiTEs) generate potent cytotoxic effects.

Methods: Alternately, click chemistry engineered, dual specific bivalent Bispecific T-cell engaging antibodies (dbBiTEs) on T-cell surfaces can be generated from parent monoclonal antibodies.

Results: We show the formation of dbBiTEs on the surface of T-cells along with the introduction of complementary 2'-OMe RNA 32-mer oligonucleotides allowing duplex formation between antibodies, designated as dbBiTERs.

Targeting miR-126 in inv(16) acute myeloid leukemia inhibits leukemia development and leukemia stem cell maintenance.

Acute myeloid leukemia (AML) harboring inv(16)(p13q22) expresses high levels of miR-126. Here we show that the CBFB-MYH11 (CM) fusion gene upregulates miR-126 expression through aberrant miR-126 transcription and perturbed miR-126 biogenesis via the HDAC8/RAN-XPO5-RCC1 axis. Aberrant miR-126 upregulation promotes survival of leukemia-initiating progenitors and is critical for initiating and maintaining CM-driven AML.

Targeted In Vivo Delivery of NF-κB Decoy Inhibitor Augments Sensitivity of B Cell Lymphoma to Therapy.

Despite recent advances, non-Hodgkin's B cell lymphoma patients often relapse or remain refractory to therapy. Therapeutic resistance is often associated with survival signaling via nuclear factor κB (NF-κB) transcription factor, an attractive but undruggable molecular target. In this study, we describe a bipartite inhibitor comprising a NF-κB-specific decoy DNA tethered to a CpG oligodeoxynucleotide (ODN) targeting Toll-like receptor-9-expressing B cell lymphoma cells.

Myeloid cell-targeted miR-146a mimic inhibits NF-κB-driven inflammation and leukemia progression in vivo.

NF-κB is a key regulator of inflammation and cancer progression, with an important role in leukemogenesis. Despite its therapeutic potential, targeting NF-κB using pharmacologic inhibitors has proven challenging. Here, we describe a myeloid cell-selective NF-κB inhibitor using an miR-146a mimic oligonucleotide conjugated to a scavenger receptor/Toll-like receptor 9 agonist (C-miR146a).

Targeted Delivery of C/EBPα-saRNA by RNA Aptamers Shows Anti-tumor Effects in a Mouse Model of Advanced PDAC.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies; it preferentially metastasizes to the liver and is the main cause of death from this disease. In previous studies, small activating RNA against CCAAT/enhancer-binding protein-α (C/EBPα-saRNA) demonstrated efficacy of PDAC in a local subcutaneous tumor model. In this study, we focused on the efficacy of C/EBPα-saRNA in advanced stage PDAC.

Axl-Targeted Delivery of the Oncosuppressor miR-137 in Non-small-Cell Lung Cancer.

Non-small-cell lung cancer (NSCLC) accounts for 85%-90% of all cases of lung cancer that is the most deadly type of cancer. Despite advances in chemotherapy and radiotherapy, severe side effects and frequent drug resistance limit the success of the treatments, and the identification of new therapeutic options still represents a crucial challenge. Here, we provide the evidence for the therapeutic potential of an aptamer-microRNA (miR) complex (AmiC) composed by an aptamer (GL21.

Targeted Delivery of miRNA Antagonists to Myeloid Cells In Vitro and In Vivo.

Elevated levels of microRNAs in cancer cells are often associated with oncogenic effects and thus provide potential therapeutic targets. However, the lack of efficient delivery methods for synthetic miRNA inhibitors, antagomiR, or anti-miR oligonucleotides hindered clinical translation of such strategies. We recently developed an approach for targeted delivery of synthetic, 2'-O-methyl-modified antagomiR molecules to normal and malignant myeloid cells and B cells by tethering to the single-stranded, phosphorothioate oligodeoxynucleotides (PSO).

STAT3 Inhibition Combined with CpG Immunostimulation Activates Antitumor Immunity to Eradicate Genetically Distinct Castration-Resistant Prostate Cancers.

Purpose: Prostate cancers show remarkable resistance to emerging immunotherapies, partly due to tolerogenic STAT3 signaling in tumor-associated myeloid cells. Here, we describe a novel strategy combining STAT3 inhibition with Toll-like Receptor 9 (TLR9) stimulation to unleash immune response against prostate cancers regardless of the genetic background.

Experimental Design: We developed and validated a conjugate of the STAT3 antisense oligonucleotide (ASO) tethered to immunostimulatory TLR9 agonist (CpG oligonucleotide) to improve targeting of human and mouse prostate cancer and myeloid immune cells, such as myeloid-derived suppressor cells (MDSC).

AptaBlocks: Designing RNA complexes and accelerating RNA-based drug delivery systems.

RNA-based therapeutics, i.e. the utilization of synthetic RNA molecules to alter cellular functions, have the potential to address targets which are currently out of scope for traditional drug design pipelines.