Chemoenzymatic Tagging of Tn/TF/STF Antigens in Living Systems.

Truncated mucin-type O-glycans, such as Tn-associated antigens, are aberrantly expressed biomarkers of cancer, but remain challenging to target. Reactive antibodies to these antigens either lack high-affinity or are prone to antigen escape. Here, we have developed a robust chemoenzymatic strategy for the global labeling of Tn-associated antigens, i.

Synchrotron speciation of umbilical cord mercury and selenium after environmental exposure in Niigata.

The insidious and deadly nature of mercury's organometallic compounds is informed by two large scale poisonings due to industrial mercury pollution that occurred decades ago in Minamata and Niigata, Japan. The present study examined chemical speciation for both mercury and selenium in a historic umbilical cord sample from a child born to a mother who lived near the Agano River in Niigata. The mother had experienced mercury exposure leading to more than 50 ppm mercury measured in her hair and was symptomatic 9 years prior to the birth.

Optimization of 3-aminotetrahydrothiophene 1,1-dioxides with improved potency and efficacy as non-electrophilic antioxidant response element (ARE) activators.

Activating NRF2-driven transcription with non-electrophilic small molecules represents an attractive strategy to therapeutically target disease states associated with oxidative stress and inflammation. In this study, we describe a campaign to optimize the potency and efficacy of a previously identified bis-sulfone based non-electrophilic ARE activator 2. This work identifies the efficacious analog 17, a compound with a non-cytotoxic profile in IMR32 cells, as well as ARE activators 18 and 22, analogs with improved cellular potency.

Drug-Initiated Activity Metabolomics Identifies Myristoylglycine as a Potent Endogenous Metabolite for Human Brown Fat Differentiation.

Worldwide, obesity rates have doubled since the 1980s and in the USA alone, almost 40% of adults are obese, which is closely associated with a myriad of metabolic diseases such as type 2 diabetes and arteriosclerosis. Obesity is derived from an imbalance between energy intake and consumption, therefore balancing energy homeostasis is an attractive target for metabolic diseases. One therapeutic approach consists of increasing the number of brown-like adipocytes in the white adipose tissue (WAT).

Iron limitation in M. tuberculosis has broad impact on central carbon metabolism.

Mycobacterium tuberculosis (Mtb), the cause of the human pulmonary disease tuberculosis (TB), contributes to approximately 1.5 million deaths every year. Prior work has established that lipids are actively catabolized by Mtb in vivo and fulfill major roles in Mtb physiology and pathogenesis.

Amyloidogenic immunoglobulin light chain kinetic stabilizers comprising a simple urea linker module reveal a novel binding sub-site.

In immunoglobulin light chain (LC) amyloidosis, the misfolding, or misfolding and misassembly of LC a protein or fragments thereof resulting from aberrant endoproteolysis, causes organ damage to patients. A small molecule "kinetic stabilizer" drug could slow or stop these processes and improve prognosis. We previously identified coumarin-based kinetic stabilizers of LCs that can be divided into four components, including a "linker module" and "distal substructure".

PD-1 and TIGIT downregulation distinctly affect the effector and early memory phenotypes of CD19-targeting CAR T cells.

CD19-targeting chimeric antigen receptor (CAR) T cells have become an important therapeutic option for patients with relapsed and refractory B cell malignancies. However, a significant portion of patients still do not benefit from the therapy owing to various resistance mechanisms, including high expression of multiple inhibitory immune checkpoint receptors. Here, we report a lentiviral two-in-one CAR T approach in which two checkpoint receptors are downregulated simultaneously by a dual short hairpin RNA cassette integrated into a CAR vector.

JAML promotes CD8 and γδ T cell antitumor immunity and is a novel target for cancer immunotherapy.

T cells are critical mediators of antitumor immunity and a major target for cancer immunotherapy. Antibody blockade of inhibitory receptors such as PD-1 can partially restore the activity of tumor-infiltrating lymphocytes (TILs). However, the activation signals required to promote TIL responses are less well characterized.

Reprogramming of Protein-Targeted Small-Molecule Medicines to RNA by Ribonuclease Recruitment.

Reprogramming known medicines for a novel target with activity and selectivity over the canonical target is challenging. By studying the binding interactions between RNA folds and known small-molecule medicines and mining the resultant dataset across human RNAs, we identified that Dovitinib, a receptor tyrosine kinase (RTK) inhibitor, binds the precursor to microRNA-21 (pre-miR-21). Dovitinib was rationally reprogrammed for pre-miR-21 by using it as an RNA recognition element in a chimeric compound that also recruits RNase L to induce the RNA's catalytic degradation.

Chemical Inhibition of ENL/AF9 YEATS Domains in Acute Leukemia.

Transcriptional coregulators, which mediate chromatin-dependent transcriptional signaling, represent tractable targets to modulate tumorigenic gene expression programs with small molecules. Genetic loss-of-function studies have recently implicated the transcriptional coactivator, ENL, as a selective requirement for the survival of acute leukemia and highlighted an essential role for its chromatin reader YEATS domain. Motivated by these discoveries, we executed a screen of nearly 300,000 small molecules and identified an amido-imidazopyridine inhibitor of the ENL YEATS domain (IC = 7 μM).

Discovery of Potent Coumarin-Based Kinetic Stabilizers of Amyloidogenic Immunoglobulin Light Chains Using Structure-Based Design.

In immunoglobulin light-chain (LC) amyloidosis, transient unfolding or unfolding and proteolysis enable aggregation of LC proteins, causing potentially fatal organ damage. A drug that kinetically stabilizes LCs could suppress aggregation; however, LC sequences are variable and have no natural ligands, hindering drug development efforts. We previously identified high-throughput screening hits that bind to a site at the interface between the two variable domains of the LC homodimer.

Switchable CAR-T Cells Outperformed Traditional Antibody-Redirected Therapeutics Targeting Breast Cancers.

Various antibody-redirected immunotherapeutic approaches, including antibody-drug conjugates (ADCs), bispecific antibodies (bsAbs), and chimeric antigen receptor-T (CAR-T) cells, have been devised to produce specific activity against various cancer types. Using genetically encoded unnatural amino acids, we generated a homogeneous Her2-targeted ADC, a T cell-redirected bsAb, and a FITC-modified antibody capable of redirecting anti-FITC CAR-T (switchable CAR-T; sCAR-T) cells to target different Her2-expressing breast cancers. sCAR-T cells showed activity against Her2-expressing tumor cells comparable to that of conventional anti-Her2 CAR-T cells and superior to that of ADC- and bsAb-based approaches.

Discovery and SAR studies of 3-amino-4-(phenylsulfonyl)tetrahydrothiophene 1,1-dioxides as non-electrophilic antioxidant response element (ARE) activators.

The transcription factor NRF2 controls resistance to oxidative insult and is thus a key therapeutic target for treating a number of disease states associated with oxidative stress and aging. We previously reported CBR-470-1, a bis-sulfone which activates NRF2 by increasing the levels of methylglyoxal, a metabolite that covalently modifies NRF2 repressor KEAP1. Here, we report the design, synthesis, and structure activity relationship of a series of bis-sulfones derived from this unexplored chemical template.

Bimodal expression of during myelomonocytic differentiation: Implications for the expansion of AML differentiation therapy.

RhoH is an unusual member of the Rho family of small GTP-binding proteins in that it lacks GTPase activity. Since the RhoH protein is constantly bound by GTP, it is constitutively active and controlled predominantly by changes in quantitative expression. Abnormal levels of gene transcripts have been linked to a range of malignancies including acute myeloid leukemia (AML).

HSP90 Inhibition Enhances Cancer Immunotherapy by Modulating the Surface Expression of Multiple Immune Checkpoint Proteins.

Cancer immunotherapies, including immune checkpoint blockade, have the potential to significantly impact treatments for diverse tumor types. At present, response failures and immune-related adverse events remain significant issues, which could be addressed using optimized combination therapies. Through a cell-based chemical screen of ∼200,000 compounds, we identified that HSP90 inhibitors robustly decrease PD-L1 surface expression, through a mechanism that appears to involve the regulation of master transcriptional regulators (i.

2-Sulfonylpyridines as Tunable, Cysteine-Reactive Electrophiles.

The emerging use of covalent ligands as chemical probes and drugs would benefit from an expanded repertoire of cysteine-reactive electrophiles for efficient and diverse targeting of the proteome. Here we use the endogenous electrophile sensor of mammalian cells, the KEAP1-NRF2 pathway, to discover cysteine-reactive electrophilic fragments from a reporter-based screen for NRF2 activation. This strategy identified a series of 2-sulfonylpyridines that selectively react with biological thiols via nucleophilic aromatic substitution (SAr).

The METLIN small molecule dataset for machine learning-based retention time prediction.

Machine learning has been extensively applied in small molecule analysis to predict a wide range of molecular properties and processes including mass spectrometry fragmentation or chromatographic retention time. However, current approaches for retention time prediction lack sufficient accuracy due to limited available experimental data. Here we introduce the METLIN small molecule retention time (SMRT) dataset, an experimentally acquired reverse-phase chromatography retention time dataset covering up to 80,038 small molecules.

Small-Molecule Stimulators of NRF1 Transcriptional Activity.

The transcription factor nuclear factor erythroid 2-related factor 1 (NRF1) maintains proteostasis and promotes cellular resilience by stimulating the transcription of proteasomal subunits and a host of protective enzymes. Although NRF1 activation would likely be beneficial in a number of disease states, information regarding its ligandability and upstream regulation are lacking. Herein we report a high-throughput chemical screen that identified selective stimulators of NRF1-driven transcription, including unannotated inhibitors of the ubiquitin proteasome system (UPS) as well as two non-UPS-targeted compounds that synergistically activate NRF1 in the context of submaximal UPS inhibition.

Tropifexor-Mediated Abrogation of Steatohepatitis and Fibrosis Is Associated With the Antioxidative Gene Expression Profile in Rodents.

Farnesoid X receptor (FXR) agonism is emerging as an important potential therapeutic mechanism of action for multiple chronic liver diseases. The bile acid-derived FXR agonist obeticholic acid (OCA) has shown promise in a phase 2 study in patients with nonalcoholic steatohepatitis (NASH). Here, we report efficacy of the novel nonbile acid FXR agonist tropifexor (LJN452) in two distinct preclinical models of NASH.

A tumor-targeted immune checkpoint blocker.

To direct checkpoint inhibition to the tumor microenvironment, while avoiding systemic immune activation, we have synthesized a bispecific antibody [norleucine4, d-Phe7]-melanocyte stimulating hormone (NDP-MSH)-antiprogrammed cell death-ligand 1 antibody (αPD-L1) by conjugating a melanocyte stimulating hormone (α-MSH) analog to the antiprogrammed cell death-ligand 1 to (αPD-L1) antibody avelumab. This bispecific antibody can bind to both the melanocortin-1 receptor (MC1R) and to PD-L1 expressed on melanoma cells and shows enhanced specific antitumor efficacy in a syngeneic B16-SIY melanoma mouse model compared with the parental antibody at a 5 mg/kg dose. Moreover, the bispecific antibody showed increased infiltrated T cells in the tumor microenvironment.

The ReFRAME library as a comprehensive drug repurposing library to identify mammarenavirus inhibitors.

Several mammarenaviruses, chiefly Lassa virus (LASV) in Western Africa and Junín virus (JUNV) in the Argentine Pampas, cause severe disease in humans and pose important public health problems in their endemic regions. Moreover, mounting evidence indicates that the worldwide-distributed mammarenavirus lymphocytic choriomeningitis virus (LCMV) is a neglected human pathogen of clinical significance. The lack of licensed mammarenavirus vaccines and partial efficacy of current anti-mammarenavirus therapy limited to an off-label use of the nucleoside analog ribavirin underscore an unmet need for novel therapeutics to combat human pathogenic mammarenavirus infections.

Cyclization-blocked proguanil as a strategy to improve the antimalarial activity of atovaquone.

Atovaquone-proguanil (Malarone®) is used for malaria prophylaxis and treatment. While the cytochrome bc1-inhibitor atovaquone has potent activity, proguanil's action is attributed to its cyclization-metabolite, cycloguanil. Evidence suggests that proguanil has limited intrinsic activity, associated with mitochondrial-function.

A cell type-selective apoptosis-inducing small molecule for the treatment of brain cancer.

Glioblastoma multiforme (GBM; grade IV astrocytoma) is the most prevalent and aggressive form of primary brain cancer. A subpopulation of multipotent cells termed GBM cancer stem cells (CSCs) play a critical role in tumor initiation, tumor maintenance, metastasis, drug resistance, and recurrence following surgery. Here we report the identification of a small molecule, termed RIPGBM, from a cell-based chemical screen that selectively induces apoptosis in multiple primary patient-derived GBM CSC cultures.

Design of Stapled Oxyntomodulin Analogs Containing Functionalized Biphenyl Cross-Linkers.

A panel of three lipid-modified, functionalized biphenyl cross-linkers (fBph) were synthesized and subsequently employed in the preparation of the stapled oxyntomodulin (OXM) analogs. In a luciferase-based reporter assay, these stapled OXM analogs showed varying degree of potency in activating GLP-1R and GCGR, presumably due to the disparate effect of the lipid chains on the local environment close to the ligand-receptor binding interface. In particular, the fBph-1 cross-linked peptide with the lipid chain attached to position-3 of the biphenyl cross-linker exhibited the highest dual agonist activity.