Pan Aurora Kinase Inhibitor: A Promising Targeted-Therapy in Dedifferentiated Liposarcomas With Differential Efficiency Depending on Sarcoma Molecular Profile

Soft tissue sarcoma (STS) are rare and aggressive tumours. Their classification includes numerous histological subtypes of frequent poor prognosis. Liposarcomas (LPS) are the most frequent type among them, and the aggressiveness and deep localization of dedifferentiated LPS are linked to high levels of recurrence. Current treatments available today lead to five-year overall survival has remained stuck around 60%-70% for the past three decades. Here, we highlight a correlation between Aurora kinasa A (AURKA) and AURKB mRNA overexpression and a low metastasis - free survival. AURKA and AURKB expression analysis at genomic and protein level on a 9-STS cell lines panel highlighted STS heterogeneity, especially in LPS subtype. AURKA and AURKB inhibition by RNAi and drug targeting with AMG 900, a pan Aurora Kinase inhibitor, in four LPS cell lines reduces cell survival and clonogenic proliferation, inducing apoptosis and polyploidy. When combined with doxorubicin, the standard treatment in STS, aurora kinases inhibitor can be considered as an enhancer of standard treatment or as an independent drug. Kinome analysis suggested its effect was linked to the inhibition of the MAP-kinase pathway, with differential drug resistance profiles depending on molecular characteristics of the tumor. Aurora Kinase inhibition by AMG 900 could be a promising therapy in STS.

Therapeutic targeting of neutrophil exocytosis

Dysregulation of neutrophil activation causes disease in humans. Neither global inhibition of neutrophil functions nor neutrophil depletion provides safe and/or effective therapeutic approaches. The role of neutrophil granule exocytosis in multiple steps leading to recruitment and cell injury led each of our laboratories to develop molecular inhibitors that interfere with specific molecular regulators of secretion. This review summarizes neutrophil granule formation and contents, the role granule cargo plays in neutrophil functional responses and neutrophil-mediated diseases, and the mechanisms of granule release that provide the rationale for development of our exocytosis inhibitors. We present evidence for the inhibition of granule exocytosis in vitro and in vivo by those inhibitors and summarize animal data indicating that inhibition of neutrophil exocytosis is a viable therapeutic strategy.

Targeted inhibition of mRNA translation initiation factors as a novel therapeutic strategy for mature B-cell neoplasms

Cancer development is frequently associated with dysregulation of mRNA translation to enhance both increased global protein synthesis and translation of specific mRNAs encoding oncoproteins. Thus, targeted inhibition of mRNA translation is viewed as a promising new approach for cancer therapy. In this article we review current progress in investigating dysregulation of mRNA translation initiation in mature B-cell neoplasms, focusing on chronic lymphocytic leukemia, follicular lymphoma and diffuse large B-cell lymphoma. We discuss mechanisms and regulation of mRNA translation, potential pathways by which genetic alterations and the tumor microenvironment alters mRNA translation in malignant B cells, preclinical evaluation of drugs targeted against specific eukaryotic initiation factors and current progress towards clinical development. Overall, inhibition of mRNA translation initiation factors is an exciting and promising area for development of novel targeted anti-tumor drugs.

Emerging small and large molecule therapeutics for respiratory syncytial virus

Introduction: Respiratory syncytial virus (RSV) causes lower respiratory tract infections and can lead to morbidity and mortality in the infant, elderly and immunocompromised. There is no vaccine and therapeutic interventions are limited. RSV disease research has yielded the development of several prophylactic and therapeutic treatments. Several promising candidates are currently under investigation.Areas covered: Small and large molecule approaches to RSV treatment were examined and categorized by their mechanism of action using data from PubMed, clinicaltrials.gov, and from the sponsoring organizations publicly available pipeline information. These results are prefaced by an overview of RSV to provide the context for rational therapy development.Expert opinion: While small molecule drugs show promise for RSV treatment, we believe that large molecule therapy using anti-RSV G and F protein monoclonal antibodies (mAbs) will most efficaciously and safely ameliorate RSV disease.

Insights into the Design of p97-targeting Small Molecules from Structural Studies on p97 Functional Mechanism

p97, also known as valosin-containing protein or CDC48, is a member of the AAA+ protein family that is highly conserved in eukaryotes. It binds to various cofactors in the body to perform its protein-unfolding function and participates in DNA repair, degradation of subcellular membrane proteins, and protein quality control pathways, among other processes. Its malfunction can lead to many diseases, such as inclusion body myopathy, associated with Paget's disease of bone and/or frontotemporal dementia, amyotrophic lateral sclerosis disease, and others. In recent years, many small-molecule inhibitors have been deployed against p97, including bis (diethyldithiocarbamate)- copper and CB-5083, which entered the first phase of clinical tests but failed. One bottleneck in the design of p97 drugs is that its molecular mechanism remains unclear. This paper summarizes recent studies on the molecular mechanisms of p97, which may lead to insight into how the next generation of small molecules targeting p97 can be designed.

Synthesis and Bioactivity of Thiazolethioacetamides as Potential Metallo-β-Lactamase Inhibitors

Metallo-β-lactamase (MβLs) mediated antibiotic resistance seriously threatens the treatment of bacterial diseases. Recently, we found that thioacetamides can be a potential MβL inhibitor skeleton. In order to improve the information of the skeleton, twelve new thiazolethioacetamides were designed by modifying the aromatic substituent. Biological activity assays identify the thiazolethioacetamides can inhibit ImiS with IC₅₀ values of 0.17 to 0.70 μM. For two of them, the IC₅₀ values against VIM-2 were 2.2 and 19.2 μM, which is lower than in our previous report. Eight of the thiazolethioacetamides are able to restore antibacterial activity of cefazolin against E.coli-ImiS by 2-4 fold. An analysis of the structure-activity relation and molecule docking show that the style and position of electron withdrawing groups in aromatic substituents play a crucial role in the inhibitory activity of thiazolethioacetamides. These results indicate that thiazolethioacetamides can serve as a potential skeleton of MβL inhibitors.

Inhibition of Heat Shock Protein 90 as a Novel Platform for the Treatment of Cancer

Heat shock protein 90 (Hsp90) plays an essential role in various physiological and pathological processes. It activates client proteins to participate in tumor progression. Blocking Hsp90 could enable effective antitumor effects in many tumor types, such as multiple myeloma and colon cancer. Recently, it has motivated an interest in Hsp90 inhibitors that bind to the N-terminal or C-terminal ATP pocket as antitumor drugs. We reviewed the data from experimental and clinical trials on Hsp90 inhibitors in the treatment of different malignancies to explore and summarize their antitumor mechanisms.

The Function of RAS Mutation in Cancer and Advances in its Drug Research

RAS (H-ras, K-ras, and N-ras), as the second largest mutated gene driver in various human cancers, has long been a vital research target for cancer. Its function is to transform the extracellular environment into a cascade of intracellular signal transduction. RAS mutant protein regulates tumor cell proliferation, apoptosis, metabolism and angiogenesis through downstream MAPK, PI3K and other signaling pathways. In KRAS or other RAS-driven cancers, current treatments include direct inhibitors and upstream/downstream signaling pathway inhibitors. However, the research on these inhibitors has been largely restricted due to their escape inhibition and off-target toxicity. In this paper, we started with the role of normal and mutant RAS genes in cancer, elucidated the relevant RAS regulating pathways, and highlighted the important research advancements in RAS inhibitor research. We concluded that for the crosstalk between RAS pathways, the effect of single regulation may be limited, and the multi-target drug combined compensation mechanism is becoming a research hotspot.

Olaparib Combined with an ATR or Chk1 Inhibitor as a Treatment Strategy for Acquired Olaparib-Resistant BRCA1 Mutant Ovarian Cells

OBJECTIVE

Despite the promise of PARP inhibitors (PARPi) for treating BRCA1/2 mutated ovarian cancer (OC), drug resistance invariably develops. We hypothesized rationale drug combinations, targeting key molecules in DNA repair pathways and the cell cycle may be synergistic and overcome acquired PARPi resistance.

METHODS

Drug sensitivity to PARPi alone and in combination with inhibitors of key DNA repair and cell cycle proteins, including ATR (VE-821), Chk1 (MK-8776), Wee1 (MK-1775), RAD51 (RI-1) was assessed in PARPi-sensitive (UWB1) and -resistant (UWB1-R) gBRCA1 mutant OC cell lines using a cell proliferation assay. The Bliss synergy model was used to estimate the two-drug combination effect and pharmacologic synergy (Bliss score ≥ 0) or antagonistic (Bliss score ≥ 0) response of the PARPi in combination with the inhibitors.

RESULTS

IC₅₀ for olaparib alone was 1.6 ± 0.9 µM compared to 3.4 ± 0.6 µM (p = 0.05) for UWB1 and UWB1-R cells, respectively. UWB1-R demonstrated increased sensitivity to ATRi (p = 0.04) compared to UWB1. Olaparib (0.3-1.25 µM) and ATRi (0.8-2.5 µM) were synergistic with Bliss scores of 17.2 ± 0.2, 11.9 ± 0.6 for UWB1 and UWB1-R cells, respectively. Olaparib (0.3-1.25 µM) and Chk1i(0.05-1.25 µM) were synergistic with Bliss scores of 8.3 ± 1.6, 5.7 ± 2.9 for UWB1 and UWB1-R cells, respectively.

CONCLUSIONS

Combining an ATRi or Chk1i with olaparib is synergistic in both PARPi-sensitive and -resistant BRCA1 mutated OC cell models, and are rationale combinations for further clinical development.

Structural Basis for Inhibiting Porcine Epidemic Diarrhea Virus Replication with the 3C-Like Protease Inhibitor GC376

Porcine epidemic diarrhea virus (PEDV), being highly virulent and contagious in piglets, has caused significant damage to the pork industries of many countries worldwide. There are no commercial drugs targeting coronaviruses (CoVs), and few studies on anti-PEDV inhibitors. The coronavirus 3C-like protease (3CL^pro) has a conserved structure and catalytic mechanism and plays a key role during viral polyprotein processing, thus serving as an appealing antiviral drug target. Here, we report the anti-PEDV effect of the broad-spectrum inhibitor GC376 (targeting 3Cpro or 3CL^pro of viruses in the picornavirus-like supercluster). GC376 was highly effective against the PEDV 3CL^pro and exerted similar inhibitory effects on two PEDV strains. Furthermore, the structure of the PEDV 3CL^pro in complex with GC376 was determined at 1.65 Å. We elucidated structural details and analyzed the differences between GC376 binding with the PEDV 3CL^pro and GC376 binding with the transmissible gastroenteritis virus (TGEV) 3CL^pro. Finally, we explored the substrate specificity of PEDV 3CL^pro at the P2 site and analyzed the effects of Leu group modification in GC376 on inhibiting PEDV infection. This study helps us to understand better the PEDV 3CL^pro substrate specificity, providing information on the optimization of GC376 for development as an antiviral therapeutic against coronaviruses.

Suppression of Musashi‑2 by the small compound largazole exerts inhibitory effects on malignant cells

RNA‑binding protein Musashi‑2 (MSI2) serves as a regulator of numerous pivotal biological processes associated with cancer initiation, development and resistance to treatment, and may represent a promising drug target. However, whether MSI2 inhibition is of value in antitumor treatment remains to be determined. The present study demonstrated that MSI2 was upregulated in non‑small cell lung cancer (NSCLC) and was inversely associated with the clinical outcome of the patients. Molecular docking analysis demonstrated that the small compound largazole binds to and may be a potential inhibitor of MSI2. Largazole markedly decreased the protein and mRNA levels of MSI2 and suppressed its downstream mammalian target of rapamycin signaling pathway. Largazole also inhibited the proliferation and induced apoptosis of NSCLC and chronic myeloid leukemia (CML) cells (including bone marrow mononuclear cells harvested from CML patients). These results indicate that MSI2 is an emerging therapeutic target for NSCLC and CML, and the MSI2 inhibitor largazole may hold promise as a treatment for these malignancies.

How Different Substitution Positions of F, Cl Atoms in Benzene Ring of 5-Methylpyrimidine Pyridine Derivatives Affect the Inhibition Ability of EGFRL858R/T790M/C797S Inhibitors: A Molecular Dynamics Simulation Study

Lung cancer is the most frequent cause of cancer-related deaths worldwide, and mutations in the kinase domain of the epidermal growth factor receptor (EGFR) are a common cause of non-small-cell lung cancers, which is a major subtype of lung cancers. Recently, a series of 5-methylpyrimidine-pyridinone derivatives have been designed and synthesized as novel selective inhibitors of EGFR and EGFR mutants. However, the binding-based inhibition mechanism has not yet been determined. In this study, we carried out molecular dynamic simulations and free-energy calculations for EGFR derivatives to fill this gap. Based on the investigation, the three factors that influence the inhibitory effect of inhibitors are as follows: (1) The substitution site of the Cl atom is the main factor influencing the activity through steric effect; (2) The secondary factors are repulsion between the F atom (present in the inhibitor) and Glu762, and the blocking effect of Lys745 on the phenyl ring of the inhibitor. (3) The two factors function synergistically to influence the inhibitory capacity of the inhibitor. The theoretical results of this study can provide further insights that will aid the design of oncogenic EGFR inhibitors with high selectivity.

Enfuvirtide-Protoporphyrin IX Dual-Loaded Liposomes: In Vitro Evidence of Synergy against HIV-1 Entry into Cells

We have developed a nanocarrier consisting of large unilamellar vesicles (LUVs) for combined delivery of two human immunodeficiency virus type 1 (HIV-1) entry inhibitors, enfuvirtide (ENF) and protoporphyrin IX (PPIX). The intrinsic lipophilicity of ENF and PPIX, a fusion inhibitor and an attachment inhibitor, respectively, leads to their spontaneous incorporation into the lipid bilayer of the LUVs nanocarrier. Both entry inhibitors partition significantly toward LUVs composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and a 9:1 mixture of POPC:1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DPPE-PEG₂₀₀₀), representative of conventional and immune-evasive drug delivery formulations, respectively. These colocalize in the core of lipid membranes. Dual-loaded nanocarriers are monodispersed and retain the size distribution, thermotropic behavior, and surface charge of the unloaded form. Combination of the two entry inhibitors in the nanocarrier resulted in improved synergy against HIV-1 entry compared to combination in free form, strongly when immune-evasive formulations are used. We propose that the improved action of the entry inhibitors when loaded into the nanocarriers results from their slow release at the site of viral entry. Overall, liposomes remain largely unexplored platforms for combination of viral entry inhibitors, with potential for improvement of current antiretroviral therapy drug safety and application. Our work calls for a reappraisal of the potential of entry inhibitor combinations and delivery for clinical use in antiretroviral therapy.

Synthesis of the Novel Covalent Cysteine Proteases Inhibitor with Iodoacetic Functional Group

This work presents the synthesis of the novel covalent inhibitor of cysteine proteases where epoxide has been replaced by the iodoacetyl functional group. The molecule, similar in action to E-64 and DCG-04, the commonly applied inhibitors, is additionally biotinylated and contains tyrosyl iodination sites. The Fmoc solid phase synthesis has been applied. Conjugation of iodoacetic acid with the peptide was optimized by testing different conjugation agents. The purity of the final product was verified by mass spectrometry and its bioactivity was tested by incubation with a model cysteine protease—staphopain C. Finally, it was shown that the synthesized inhibitor binds to the protein at the ratio of 1:1. More detailed analysis by means of tandem mass spectrometry proved that the inhibitor binds to the cysteine present in the active site of the enzyme.

Second-generation 4,5,6,7-tetrahydrobenzo[d]thiazoles as novel DNA gyrase inhibitors

Aim: DNA gyrase and topoisomerase IV are essential bacterial enzymes, and in the fight against bacterial resistance, they are important targets for the development of novel antibacterial drugs. Results: Building from our first generation of 4,5,6,7-tetrahydrobenzo[d]thiazole-based DNA gyrase inhibitors, we designed and prepared an optimized series of analogs that show improved inhibition of DNA gyrase and topoisomerase IV from Staphylococcus aureus and Escherichia coli, with IC₅₀ values in the nanomolar range. Importantly, these inhibitors also show improved antibacterial activity against Gram-positive strains. Conclusion: The most promising inhibitor, 29, is active against Enterococcus faecalis, Enterococcus faecium and S. aureus wild-type and resistant strains, with minimum inhibitory concentrations between 4 and 8 μg/ml, which represents good starting point for development of novel antibacterials.

Compound screening in cell-based models of tau inclusion formation: Comparison of primary neuron and HEK293 cell assays

The hallmark pathological features of Alzheimer's disease (AD) brains are senile plaques, comprising β-amyloid (Aβ) peptides, and neuronal inclusions formed from tau protein. These plaques form 10-20 years before AD symptom onset, whereas robust tau pathology is more closely associated with symptoms and correlates with cognitive status. This temporal sequence of AD pathology development, coupled with repeated clinical failures of Aβ-directed drugs, suggests that molecules that reduce tau inclusions have therapeutic potential. Few tau-directed drugs are presently in clinical testing, in part because of the difficulty in identifying molecules that reduce tau inclusions. We describe here two cell-based assays of tau inclusion formation that we employed to screen for compounds that inhibit tau pathology: a HEK293 cell-based tau overexpression assay, and a primary rat cortical neuron assay with physiological tau expression. Screening a collection of ∼3500 pharmaceutical compounds with the HEK293 cell tau aggregation assay, we obtained only a low number of hit compounds. Moreover, these compounds generally failed to inhibit tau inclusion formation in the cortical neuron assay. We then screened the Prestwick library of mostly approved drugs in the cortical neuron assay, leading to the identification of a greater number of tau inclusion inhibitors. These included four dopamine D2 receptor antagonists, with D2 receptors having previously been suggested to regulate tau inclusions in a Caenorhabditis elegans model. These results suggest that neurons, the cells most affected by tau pathology in AD, are very suitable for screening for tau inclusion inhibitors.

A highly selective inhibitor of interleukin-1 receptor-associated kinases 1/4 (IRAK-1/4) delineates the distinct signaling roles of IRAK-1/4 and the TAK1 kinase

Interleukin-1 receptor-associated kinase-1 (IRAK-1) and IRAK-4, as well as transforming growth factor β-activated kinase 1 (TAK1), are protein kinases essential for transducing inflammatory signals from interleukin receptors. IRAK family proteins and TAK1 have high sequence identity within the ATP-binding pocket, limiting the development of highly selective IRAK-1/4 or TAK1 inhibitors. Beyond kinase activity, IRAKs and TAK1 act as molecular scaffolds along with other signaling proteins, complicating the interpretation of experiments involving knockin or knockout approaches. In contrast, pharmacological manipulation offers the promise of targeting catalysis-mediated signaling without grossly disrupting the cellular architecture. Recently, we reported the discovery of takinib, a potent and highly selective TAK1 inhibitor that has only marginal activity against IRAK-4. On the basis of the TAK1-takinib complex structure and the structure of IRAK-1/4, here we defined critical contact sites of the takinib scaffold within the nucleotide-binding sites of each respective kinase. Kinase activity testing of takinib analogs against IRAK-4 identified a highly potent IRAK-4 inhibitor (HS-243). In a kinome-wide screen of 468 protein kinases, HS-243 had exquisite selectivity toward both IRAK-1 (IC50 = 24 nm) and IRAK-4 (IC50 = 20 nm), with only minimal TAK1-inhibiting activity (IC50 = 0.5 μm). Using HS-243 and takinib, we evaluated the consequences of cytokine/chemokine responses after selective inhibition of IRAK-1/4 or TAK1 in response to lipopolysaccharide challenge in human rheumatoid arthritis fibroblast-like synoviocytes. Our results indicate that HS-243 specifically inhibits intracellular IRAKs without TAK1 inhibition and that these kinases have distinct, nonredundant signaling roles.

Synthesis of New Series of 2-C-(β-D-glucopyranosyl)-Pyrimidines and Their Evaluation as Inhibitors of Some Glycoenzymes

Despite the substantial interest in C-glycosyl heterocycles as mimetics of biologically active native glycans, the appearance of C-glycopyranosyl derivatives of six-membered heterocycles, both in synthetic and biological contexts, is rather scarce. As part of our ongoing research program aimed at preparing hitherto barely known 2-C-glycopyranosyl pyrimidines, the goal of the present study was to synthesize new 5-mono- and multiply substituted derivatives of this compound class. Thus, 2-C-(β-D-glucopyranosyl)-5,6-disubstituted-pyrimidin-4(3H)-ones and 4-amino-2-C-(β-D-glucopyranosyl)-5,6-disubstituted-pyrimidines were prepared by base-mediated cyclocondensations of O-perbenzylated and O-unprotected C-(β-D-glucopyranosyl) formamidine hydrochlorides with methylenemalonic acid derivatives. The 2-C-(β-D-glucopyranosyl)-5-substituted-pyrimidines were obtained from the same amidine precursors upon treatment with vinamidinium salts. The deprotected derivatives of these pyrimidines were tested as inhibitors of some glycoenzymes. None of them showed inhibitory activity towards glycogen phosphorylase and α- and β-glucosidase enzymes, but some members of the sets exhibited moderate inhibition against bovine liver β-galactosidase.

Targeting PIN1 as a Therapeutic Approach for Hepatocellular Carcinoma

PIN1 is a peptidyl-prolyl cis/trans isomerase that specifically binds and catalyzes the cis/trans isomerization of the phosphorylated serine or threonine residue preceding a proline (pSer/Thr-Pro) motif of its interacting proteins. Through this phosphorylation-dependent prolyl isomerization, PIN1 is involved in the regulation of various important cellular processes including cell cycle progression, cell proliferation, apoptosis and microRNAs biogenesis; hence its dysregulation contributes to malignant transformation. PIN1 is highly expressed in hepatocellular carcinoma (HCC). By fine-tuning the functions of its interacting proteins such as cyclin D1, x-protein of hepatitis B virus and exportin 5, PIN1 plays an important role in hepatocarcinogenesis. Growing evidence supports that targeting PIN1 is a potential therapeutic approach for HCC by inhibiting cell proliferation, inducing cellular apoptosis, and restoring microRNAs biogenesis. Novel formulation of PIN1 inhibitors that increases in vivo bioavailability of PIN1 inhibitors represents a promising future direction for the therapeutic strategy of HCC treatment. In this review, the mechanisms underlying PIN1 over-expression in HCC are explored. Furthermore, we also discuss the roles of PIN1 in HCC tumorigenesis and metastasis through its interaction with various phosphoproteins. Finally, recent progress in the therapeutic options targeting PIN1 for HCC treatment is examined and summarized.

Synthesis and human carbonic anhydrase I, II, VA, and XII inhibition with novel amino acid-sulphonamide conjugates

A series of amino acid-sulphonamide conjugates was prepared through benzotriazole mediated coupling reactions and characterised by ¹H-NMR, ¹³C-NMR, MS, and FTIR spectroscopic techniques as well as elemental analysis. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was determined against four human (h) isoforms, hCA I, hCA II, hCA VA, and hCA XII. Most of the synthesised compounds showed effective in vitro CA inhibitory properties. The new amino acid-sulphonamide conjugates showed potent inhibitory activity against hCA II, some of them at subnanomolar levels, exhibiting more effective inhibitory activity compared to the standard drug acetazolamide. Some of these sulphonamides were also found to be effective inhibitors of hCA I, hCA VA, and hCA XII, with activity from the low to high nanomolar range.

A specific amino acid context in EGFR and HER2 phosphorylation sites enables selective binding to the active site of Src homology phosphatase 2 (SHP2)

The Src homology phosphatase 2 (SHP2) is a cytoplasmic enzyme that mediates signaling induced by multiple receptor tyrosine kinases, including signaling by the epidermal growth factor receptor (EGFR) family (EGFR1-4 or the human homologs HER1-4). In EGFR (HER1) and EGFR2 (HER2) signaling, SHP2 increases the half-life of activated Ras by blocking recruitment of Ras GTPase-activating protein (RasGAP) to the plasma membrane through dephosphorylation of docking sites on the receptors. However, it is unclear how SHP2 selectively recognizes RasGAP-binding sites on EGFR and HER2. In this report, we show that SHP2-targeted pTyr residues exist in a specific amino acid context that allows selective binding. More specifically, we show that acidic residues N-terminal to the substrate pTyr in EGFR and HER2 mediate specific binding by the SHP2 active site, leading to blockade of RasGAP binding and optimal signaling by the two receptors. Molecular modeling studies revealed that a peptide derived from the region of pTyr⁹⁹²-EGFR packs well and makes stronger interactions with the SHP2 active site than with the SHP1 active site, suggesting a built-in mechanism that enables selective substrate recognition by SHP2. A phosphorylated form of this peptide inhibits SHP2 activity in vitro and EGFR and HER2 signaling in cells, suggesting inhibition of SHP2 protein tyrosine phosphatase activity by this peptide. Although we do not expect this peptide to be a strong inhibitor by itself, we foresee that the insights into SHP2 selectivity described here will be useful in future development of active-site small molecule-based inhibitors.

Patent spotlight: small-molecule lysine acetyltransferase inhibitors (KATi)

Lysine (or histone) acetyltransferases plays a key role in genome maintenance and gene regulation and dysregulation of acetylation is a recognized feature of many diseases, including several cancers. Here, the patent landscape surrounding lysine acetyltransferase inhibitors (KATi or HATi), with a focus on small-molecule compounds, is outlined and assessed. Overall, the 36 KATi-specific patents found were categorized into two distinct groups: specific small-molecule inhibitors (compounds and molecules) and patents applying KATi for targeted disease treatment. These patents recognize the emergent potential of KATi to significantly impact on the management of many diseases (including multiple cancer types, neurological disorders and immunological syndromes), improving the range of treatments (and drug classes) available for personalized medicine.

Small Molecule Inhibition of CPS1 Activity through an Allosteric Pocket

Carbamoyl phosphate synthetase 1 (CPS1) catalyzes the first step in the ammonia-detoxifying urea cycle, converting ammonia to carbamoyl phosphate under physiologic conditions. In cancer, CPS1 overexpression supports pyrimidine synthesis to promote tumor growth in some cancer types, while in others CPS1 activity prevents the buildup of toxic levels of intratumoral ammonia to allow for sustained tumor growth. Targeted CPS1 inhibitors may, therefore, provide a therapeutic benefit for cancer patients with tumors overexpressing CPS1. Herein, we describe the discovery of small-molecule CPS1 inhibitors that bind to a previously unknown allosteric pocket to block ATP hydrolysis in the first step of carbamoyl phosphate synthesis. CPS1 inhibitors are active in cellular assays, blocking both urea synthesis and CPS1 support of the pyrimidine biosynthetic pathway, while having no activity against CPS2. These newly discovered CPS1 inhibitors are a first step toward providing researchers with valuable tools for probing CPS1 cancer biology.

A Synergistic Anticancer FAK and HDAC Inhibitor Combination Discovered by a Novel Chemical-Genetic High-Content Phenotypic Screen

We mutated the focal adhesion kinase (FAK) catalytic domain to inhibit binding of the chaperone Cdc37 and ATP, mimicking the actions of a FAK kinase inhibitor. We reexpressed mutant and wild-type FAK in squamous cell carcinoma (SCC) cells from which endogenous FAK had been deleted, genetically fixing one axis of a FAK inhibitor combination high-content phenotypic screen to discover drugs that may synergize with FAK inhibitors. Histone deacetylase (HDAC) inhibitors represented the major class of compounds that potently induced multiparametric phenotypic changes when FAK was rendered kinase-defective or inhibited pharmacologically in SCC cells. Combined FAK and HDAC inhibitors arrest proliferation and induce apoptosis in a subset of cancer cell lines in vitro and efficiently inhibit their growth as tumors in vivo Mechanistically, HDAC inhibitors potentiate inhibitor-induced FAK inactivation and impair FAK-associated nuclear YAP in sensitive cancer cell lines. Here, we report the discovery of a new, clinically actionable, synergistic combination between FAK and HDAC inhibitors.

An update on Wnt signaling pathway in cancer

Wnt signaling involves many aspects of development, cell biology and physiology. Mutations in the Wnt gene can lead to abnormal embryonic development and cancer formation, including various aspects that affect proliferation, morphogenesis, and differentiation. The occurrence and development of tumors is a complex process involving multiple factors. The Wnt signaling pathway participates in this process as an anti-tumor target by activating multiple gene transcriptions. The emergence of Wnt pathway inhibitors and targeted drugs has opened up a new world of cancer treatment. This review focuses on the mechanism of action of the Wnt signaling pathway in different cancers. Secondly, we have organized and introduced the latest Wnt anti-tumor drugs.