Discovery of novel phenyl urea SHP2 inhibitors with anti-colon cancer and potential immunomodulatory effects.

Src Homology-2 Domain Containing Protein Tyrosine Phosphatase-2 (SHP2) is a non-receptor-type protein tyrosine phosphatase (PTP), which is recognized as potential and attractive cancer therapeutic target. Currently, no SHP2 inhibitors have been approved for clinical use, and colorectal cancer (CRC) cells exhibited frequent resistance to reported SHP2 inhibitors, such as SHP099 and TNO155. Herein, we reported our discovery and optimization of phenyl urea as novel SHP2 inhibitors.

Discovery of small molecules for autophagy-lysosome degradation of immune checkpoint proteins.

Targeted protein degradation (TPD) technologies, particularly proteolysis targeting chimeras (PROTACs), have emerged as a promising branch of targeted therapy. Current ubiquitin-proteasome-dependent TPD technologies are limited to targeting intracellular proteins. Although the blockade of immune checkpoints has achieved great clinical success, most immune checkpoints are transmembrane proteins, which are difficult to be ubiquitinated and degraded by PROTACs.

Discovery of Benzo[]oxazoles as Novel Dual Small-Molecule Inhibitors Targeting PD-1/PD-L1 and VISTA Pathway.

The blockers of programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) pathway have achieved great clinical success. However, the limited efficacy and low tumor response rate of anti-PD-1/PD-L1 monotherapy limit the clinical application of PD-1/PD-L1 inhibitors. V-domain immunoglobulin suppressor of T-cell activation (VISTA), a novel checkpoint regulator, exhibits potential synergy with PD-1/PD-L1 in enhancing antitumor immunity.

Beyond inhibition against the PD-1/PD-L1 pathway: development of PD-L1 inhibitors targeting internalization and degradation of PD-L1.

Tumor cells hijack the programmed cell death protein-1 (PD-1)/programmed cell death ligand-1 (PD-L1) pathway to suppress the immune response through overexpressing PD-L1 to interact with PD-1 of T cells. With in-depth ongoing research, tumor-intrinsic PD-L1 is found to play important roles in tumor progression without interaction with PD-1 expressed on T cells, which provides an additional important target and therapeutic approach for development of PD-L1 inhibitors. Existing monoclonal antibody (mAb) drugs against the PD-1/PD-L1 pathway generally behave by conformationally blocking the interactions of PD-1 with PD-L1 on the cell surface.

Rising Star in Immunotherapy: Development and Therapeutic Potential of Small-Molecule Inhibitors Targeting Casitas B Cell Lymphoma-b (Cbl-b).

Casitas B cell lymphoma-b (Cbl-b) is a vital negative regulator of TCR and BCR signaling pathways, playing a significant role in setting an appropriate threshold for the activation of T cells and controlling the tolerance of peripheral T cells via a variety of mechanisms. Overexpression of Cbl-b leads to immune hyporesponsiveness of T cells. Conversely, the deficiency of Cbl-b in T cells results in markedly increased production of IL-2, even in the lack of CD28 costimulation in vitro.

Discovery of Novel Phenoxyaryl Pyridones as Bromodomain and Extra-Terminal Domain (BET) Inhibitors with High Selectivity for the Second Bromodomain (BD2) to Potentially Treat Acute Myeloid Leukemia.

Bromodomain-selective BET inhibition has emerged as a promising strategy to improve the safety profiles of -BET inhibitors. Herein, we report the discovery of potent phenoxyaryl pyridones as highly BD2-selective BET inhibitors. Compound (IC = 2.

Discovery of Novel PD-L1 Inhibitors That Induce the Dimerization, Internalization, and Degradation of PD-L1 Based on the Fragment Coupling Strategy.

Tumor cells can evade immune surveillance through overexpressing programmed cell death-ligand 1 (PD-L1) to interact with programmed cell death-1 (PD-1). Besides, tumor-intrinsic PD-L1 is involved in tumor progression without interaction with PD-1, which provides more challenges for the discovery of PD-L1 inhibitors. Herein, we report the discovery of novel PD-L1 inhibitors using the fragment coupling strategy.

Novel Benzimidazoles as Potent Small-Molecule Inhibitors and Degraders of V-Domain Ig Suppressor of T-Cell Activation (VISTA).

The V-domain Ig suppressor of T-cell activation (VISTA) is a promising negative immune checkpoint and plays a critical role in the regulation of the quiescence of naïve T lymphocytes. Most patients however do not experience durable disease control from current immune checkpoint inhibitors and discovery of inhibitors targeting novel immune checkpoints is necessary. Herein, we report our discovery and optimization of benzimidazoles as the bifunctional inhibitors of VISTA.

Discovery of diaminotriazine carboxamides as potent inhibitors of hematopoetic progenitor kinase 1.

Hematopoietic progenitor kinase 1 (HPK1), a member of mitogen-activated protein kinase kinase kinase kinase (MAP4K) family of Ste20 serine/threonine kinases, is a negative regulator of T-cell receptor (TCR) signaling. Inactivating HPK1 kinase has been reported to be sufficient to elicit antitumor immune response. Therefore, HPK1 has attracted much attention as a promising target for tumor immunotherapy.

Discovery of quinazolin-4-one-based non-covalent inhibitors targeting the severe acute respiratory syndrome coronavirus 2 main protease (SARS-CoV-2 M).

The COVID-19 pandemic caused by SARS-CoV-2 continues to pose a great threat to public health while various vaccines are available worldwide. Main protease (M) has been validated as an effective anti-COVID-19 drug target. Using medicinal chemistry and rational drug design strategies, we identified a quinazolin-4-one series of nonpeptidic, noncovalent SARS-CoV-2 M inhibitors based on baicalein, 5,6,7-trihydroxy-2-phenyl-4H-chromen-4-one.

Design, synthesis, and evaluation of PD-1/PD-L1 small-molecule inhibitors bearing a rigid indane scaffold.

Discovery of small-molecule inhibitors against programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) axis provides a promising alternative to overcome the inevitable defects of PD-1/PD-L1 monoclonal antibodies (mAbs). Here, we report a series of indanes as novel small-molecule inhibitors of PD-1/PD-L1 interaction. Thirty-one indanes were synthesized and the structure-activity relationships (SARs) demonstrated that conformational restriction with (S)-indane is superior in potency to inhibit the interaction of PD-1 and PD-L1.

Development and Therapeutic Implications of Tyrosine Kinase 2 Inhibitors.

Janus kinases (JAKs) are central components in cytokine signaling pathways. A number of small molecule JAK inhibitors have been approved to treat a wide range of inflammatory and autoimmune diseases. Due to safety concerns of pan-JAK inhibition, the thrust of current research is toward the discovery of isoform-selective JAK inhibitors.

Design, synthesis, biological evaluation of urea substituted 1,2,5-oxadiazole-3-carboximidamides as novel indoleamine 2,3-dioxygenase-1 (IDO1) inhibitors.

Indoleamine 2,3-dioxygenase-1 (IDO1) has been considered as an attractive target for oncology immunotherapy due to its immunosuppressive effects on the tumor microenvironment. The most advanced IDO1 inhibitor epacadostat in combination with anti-PD-1 antibody failed to show desirable objective response. Epacadostat is now reevaluated in phase III clinical trials, but its pharmacokinetic (PK) properties are unsatisfactory.

Dual Nicotinamide Phosphoribosyltransferase (NAMPT) and Indoleamine 2,3-Dioxygenase 1 (IDO1) Inhibitors for the Treatment of Drug-Resistant Nonsmall-Cell Lung Cancer.

Depleting NAD by blocking its biosynthesis has emerged as an attractive anticancer strategy. Simultaneous blockade of NAD production from the salvage and synthesis pathways by targeting NAMPT and IDO1 could achieve more effective NAD reduction and, subsequently, more robust antitumor efficacy. Herein, we report the discovery of the first series of dual NAMPT and IDO1 inhibitors according to multitarget drug rationales.

The development of small-molecule inhibitors targeting HPK1.

Hematopoietic progenitor kinase 1 (HPK1), a 97-kDa serine/threonine Ste20-related protein kinase, is a negative regulator of T cells, B cells, and dendritic cells-mediated immune responses and is primarily expressed in hematopoietic lineage cells. HPK1 regulates different cellular processes by interacting with a variety of substrates and adaptors, including immune cell activation, cellular differentiation, proliferation, adhesion, and apoptosis. In HPK1 mice, T cells over-proliferate in response to stimulation by anti-CD3 and anti-CD28 antibodies, and these cells can secrete more proinflammatory cytokines to enhance T-cell activation and tumor growth inhibition when immunized with T cell-dependent antigens.

Development of Inhibitors Targeting the V-Domain Ig Suppressor of T Cell Activation Signal Pathway.

Blockade of cytotoxic T lymphocyte antigen 4 (CTLA-4) and programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) has produced considerable therapeutic effect, but only in a fraction of patients, so more targets are being investigated. VISTA (V-domain Ig suppressor of T cell activation) is a novel immune checkpoint that is broadly expressed within hematopoietic cells and multiple cancers (low expressing frequency on solid tumors), particularly those with a poor immunotherapy response rate. As a result, VISTA has been identified as an appealing target for immunotherapy, and several VISTA inhibitors are currently in clinical and preclinical trials.

Recent Insights of Metformin on Hepatocellular Carcinoma (HCC).

Metformin is an oral hypoglycemic drug, the first option used to treat type 2 diabetes mellitus due to its high efficacy and low cost. Recently, it has drawn attention among researchers due to its new-found antitumor effect. Growing evidence showed that metformin could inhibit cancer progression, especially in hepatocellular carcinoma, and several clinical trials are underway.

Discovery of Small Molecules Simultaneously Targeting NAD(P)H:Quinone Oxidoreductase 1 and Nicotinamide Phosphoribosyltransferase: Treatment of Drug-Resistant Non-small-Cell Lung Cancer.

Targeting NAD metabolism has emerged as an effective anticancer strategy. Inspired by the synergistic antitumor effect between NAD(P)H:quinone oxidoreductase 1 (NQO1) substrates increasing the NAD consumption and nicotinamide phosphoribosyltransferase (NAMPT) inhibitors hampering the NAD synthesis, first-in-class small molecules simultaneously targeting NQO1 and NAMPT were identified through structure-based design. In particular, compound is an excellent NQO1 substrate that is processed faster than TSA by NQO1 and exhibited a slightly decreased NAMPT inhibitory potency than that of FK866.

Rational design of a potent macrocyclic peptide inhibitor targeting the PD-1/PD-L1 protein-protein interaction.

We report optimization by rational design of JMPDP-027, a potent cyclic peptide that interferes with the PD-1/PD-L1 protein-protein interaction. JMPDP-027 shows a potent restoring ability towards T-cells with an EC of 5.9 nM that is comparable to that of the anti-PD-1 monoclonal antibody pembrolizumab.

Design, Synthesis, and Evaluation of PD-1/PD-L1 Antagonists Bearing a Benzamide Scaffold.

Several antibodies targeting programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) have been approved by the U.S. Food and Drug Administration (FDA) for cancer therapy.

Novel Biphenyl Pyridines as Potent Small-Molecule Inhibitors Targeting the Programmed Cell Death-1/Programmed Cell Death-Ligand 1 Interaction.

With the successful clinical application of anti-programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) monoclonal antibodies (mAb), targeting the PD-1/PD-L1 interaction has become a promising method for the discovery of cancer therapy. Due to the inherent limitations of antibodies, it is necessary to search for small-molecule inhibitors against the PD-1/PD-L1 axis. We report the design, synthesis, and evaluation and of a series of novel biphenyl pyridines as the inhibitors of PD-1/PD-L1.

Structure-Based Design of a Selective Class I Histone Deacetylase (HDAC) Near-Infrared (NIR) Probe for Epigenetic Regulation Detection in Triple-Negative Breast Cancer (TNBC).

Abnormally high levels of class I histone deacetylases (HDACs) are associated with triple-negative breast cancer (TNBC) proliferation, malignant transformation, and poor prognosis of patients. Herein, we report a near-infrared imaging probe for TNBC detection via visualizing class I HDACs. Conjugating Cy5.

Dual nicotinamide phosphoribosyltransferase and epidermal growth factor receptor inhibitors for the treatment of cancer.

Multitarget drugs have emerged as a promising treatment modality in modern anticancer therapy. Taking advantage of the synergy of NAMPT and EGFR inhibition, we have developed the first compounds that serve as dual inhibitors of NAMPT and EGFR. On the basis of CHS828 and erlotinib, a series of hybrid molecules were successfully designed and synthesized by merging of the pharmacophores.