Design of small molecules targeting molecular chaperone system: review and perspective / 药学学报

Molecular chaperone system, which mainly consist of heat shock proteins family and their cochaperones, is crucial for maintaining proteostasis in life. It assists in folding, maturation and ubiquitin-proteasome-mediated degradation of proteins, thus to play a key role in cell proliferation and apoptosis. Functional disorder of molecular chaperone system is highly relevant to occurrence and development of multiple diseases including cancers, autoimmune disease/inflammatory, infective diseases, neurodegenerative disease, etc. Therefore, molecular chaperone system has long been regarded as potential drug targets. In this review, we outline the progress in the design of small molecules targeting molecular chaperone system and analyze the features of small molecules with different mechanisms. Finally, we put forward expects about potential development directions for future drug design in this field.

First-in-class small molecule drugs in 2022 / 药学学报

2022 is the third year of the global COVID-19 pandemic, and its troubles on new drug discovery are gradually apparent. 37 new drugs were approved by the FDA's Center for Drug Evaluation and Research (CDER) last year, down from the peak of 50 new drug approvals in 2021. Notably, first-in-class drugs still occupy a dominant position this year, with a total of 21 drugs. Among them, 7 are first-in-class small molecule drugs. Although the total number of new drug approvals in 2022 sharply decreased, some first-in-class small molecule drugs were regarded as significant, including mitapivat, the first oral activator targeting the pyruvate kinase (PK); mavacamten, the first selective allosteric inhibitor targeting the myocardial β myosin ATPase; deucravacitinib, the first deuterated allosteric inhibitor targeting the tyrosine kinase 2 (TYK2); and lenacapavir, the first long-acting inhibitor targeting the HIV capsid. Generally, the research of first-in-class drugs needs to focus on difficult clinical problems and can treat some specific diseases through novel targets and biological mechanisms. There are tremendous challenges in the research processes of new drugs, including biological mechanism research, target selection, molecular screening, lead compound identification and druggability optimization. Therefore, the success of first-in-class drugs development has prominent guidance significance for new drug discovery. This review briefly describes the discovery background, research and development process and therapeutic application of 3 first-in-class small molecule drugs to provide research ideas and methods for more first-in-class drugs.

The development of small-molecule inhibitors targeting MYC / 药学学报

The MYC gene, one of the most common dysregulated driver genes in human cancers, is composed of three paralogous genes C-MYC, N-MYC and L-MYC. It is abnormally activated in more than half of cancer types. Since MYC plays an important role in the formation, maintenance and progression of cancer, targeting MYC is an effective strategy for cancer treatment. As a potential anti-cancer target, MYC is considered "undruggable" because it lacks a suitable pocket for accommodating small molecule inhibitors. Recently, under the guidance of protein structure information and many computational tools, many indirect strategies to inhibit MYC have emerged and shown favorable anti-cancer effects in tumor models. In this paper, the recent small molecules that indirectly target MYC are divided into inhibitors acting on the protein-protein interaction (PPI) among MYC and other proteins, and targeting inhibitors regulating MYC action. Additionally, the introduction and assessment towards compounds with different mechanisms are summarized to provide reference for the further research of MYC inhibitors.

First-in-class small molecule drugs in 2020 / 药学学报

With the development of the research on innovative drugs in our country, first-in-class drugs are becoming a main goal for both pharmaceutical companies and scientific institutions. Discovery of first-in-class drugs require amounts of basic research, a massive investment and novel methods, acting as a beacon for the new drug development. In 2020, FDA totally approved 53 novel drugs with 38 small molecules, which still accounting for a major component. Among them, many first-in-class drugs are important including a first EZH2 inhibitor (tazemetostat) for the treatment of epithelioid sarcoma, a first attachment inhibitor (fostemsavir) with novel mechanism for the treatment of HIV, a first farnesyltransferase inhibitor (lonafarnib) for the treatment of Hutchinson-Gilford progeria syndrome (HGPS) and a first MC4 receptor agonist for the treatment of rare genetic diseases of obesity, etc. The research procedures of the above drugs are representative with new ideas. In this review, we outline 3 of the first-in-class drugs to discuss the research background, discovery and development process as well as the therapeutic potentials to provide methods and ideas for the further drug development.

Design, synthesis and activity evaluation of protein arginine methyltransferase 5 inhibitor / 药学学报

Protein arginine methyltransferase 5 (PRMT5) is an important type II human methyltransferase. It catalyzes the symmetrical double-methylation of many histones and non-histones, and it is highly expressed in many kinds of tumors. PRMT5 has been proven to be a potential new target for cancer treatment. Based on the reported crystal complex of EPZ015666 with PRMT5, a series of new compounds was designed using GSK3326595 (EPZ015938) as the lead compound and using the conformational restriction approach. We found that compounds B8 and the C series of derivatives displayed enzyme inhibitory activity comparable to that of GSK3326595. Compounds C3 and C4 showed poor permeability in Caco-2 cells, and that might be one of the reasons for their poor anti-proliferative activity against Z-138 cells. These data provide insights for further structural optimization.

The development of small-molecule inhibitors that target PRC2-related proteins / 药学学报

Abnormal expression of polycomb repressive complex 2 (PRC2) is related to the development of a variety of diseases. Inhibition of normal or overactive PRC2 can reduce cell survival and inhibit tumor growth in several cancers. Therefore, the identification and development of small molecule inhibitors has become an active field of current epigenetic-related anti-tumor strategies. A small molecule inhibitor targeting the S-adenosyl-L-methionine (SAM) binding site of enhancer of zeste homologue 2 (EZH2) has been approved by FDA. However, acquired drug resistance is of concern. Drugs targeting two different binding sites of embryonic ectoderm development (EED) are also being developed. The development of EZH2-EED proton pump inhibitor has attracted extensive attention due to its unique mechanism of action. In this paper, we review the research progress on various small molecule inhibitors that target PRC2-related proteins to provide a basis for further research and development of related drugs.

First-in-class small molecule drugs in 2018 / 药学学报

In 2018, FDA approved 59 kinds of new drugs in all, breaking the record of 53 set in 1993. There were 34 types of small molecule drugs, which accounted for 64% of the whole new drugs. Of these 34 new small molecule drugs, 9 first-in-class ones marked a milestone for the subsequent drug discovery and development. These include Glasdegib, the world's first small molecule inhibitor targeting Smo through Hedgehog signaling pathway; Ivosidenib, the first small molecule inhibitor targeting mutant IDH1; Tecovirimat, the first small molecule drug for anti-variola virus therapy through targeting p37; Baloxavir marboxil, the first anti-flu drug targeting cap-dependent endonuclease; Elagolix sodium, the first small molecule inhibitor in treating endometriosis by targeting GnRH-R, etc. The research and development of first-in-class drugs is always full of obstacles and challenges. However, once they were successfully recognized as the "heavy bomb" drugs, they would become huge benefits. This article chose the representative first-in-class small molecule drugs that were approved in 2018 as examples to analyze their development processes in an attempt to provide guidance for the research and development of more first-in-class drugs.

Protein degradation as an innovative strategy in drug discovery / 药学学报

The success rate of mechanism-based drug discovery depends on the drug targets. With the rapid development of genomics and proteomics, a lot of nonenzymic proteins have been identified as potential drug targets. However, these nonenzymic proteins cannot be regulated by occupying the active site, which were recognized as undruggable targets. Direct regulation of the concentration of these proteins in cells by the innate ubiquitin-proteasome is a potential approach to target these proteins. The ubiquitination of target protein by E3 ligase is the key step for ubiquitin-proteasome mediated protein degradation. Proteolysis targeting chimeras (PROTACs) can facilitate the assembly of complex that consists of the target protein and E3 ligase. The target protein will be ubiquitinated, leading to the degradation by proteasome. This type of regulation mechanism can expand the scope of potential drug targets, and the development of PROTACs may be an innovative strategy in drug discovery.

HTRF-based method for determination of HSP90-HOP inhibition activity and its application / 药学学报

HSP90 is widely expressed in cells with the main function in assisting the maturation of other proteins that are called clients. Many clients play critical roles in the occurrence and development of cancer. Inhibition of HSP90 can lead to degradation of the oncogenic proteins, and result in potent anti-cancer effects. HSP90-HOP interaction is critical for the chaperone function of HSP90, thereby disruption of the HSP90-HOP interaction is a novel strategy in the inhibition of HSP90. Based on the technology of homogeneous time-resolved fluorescence (HTRF), we developed a new assay for the identification of new inhibitors of HSP90-HOP interaction. This method was evaluated in the study of the HSP90-HOP inhibition activity of the pentapeptide MEEVD from HSP90 C-terminal and its derivatives. This study can provide a basis for the screening and discovery of novel HSP90-HOP disruptors.

Progress in research of the structural optimization of natural product-like Garcinia caged xanthones / 药学学报

Designing of natural product-like compounds using natural products as template structures is an important strategy for the discovery of new drugs. Gambogic acid (GA), which is a Garcinia natural product with a unique caged xanthone scaffold, inhibits potent antitumor activity both in vitro and in vivo. This review summarized the researches on the identification of the antitumor pharmacophore of GA, and the design, structural optimization and structure-activity relationship (SAR) of natural product-like caged xanthones based on it.

Synthesis and antitumor activity of novel tetrahydro-beta-carboline derivatives as KSP inhibitors / 药学学报

Inhibitors of kinesin spindle protein (KSP) are a promising class of anticancer agents that cause mitotic arrest and induce apoptosis of tumor cells. A series of novel tetrahydro-beta-carboline derivatives were synthesized as kinesin spindle protein inhibitor and evaluated as potential antitumor agents. All compounds showed promising KSP inhibitiory activity. Compounds 8 and 9 exhibited better antitumor activity (Lung/A549, Stomach/AGS) than CK0106023 with GI50/IC50 values (1.07/1.62 and 1.46/3.27 micromol x L(-1), 1.09/>10 and 1.22/6.33 micromol x L(-1), respectively).

Recent advances in chemistry and biology of gamboge / 中国中药杂志

Gamboge, the resin of Garcinia hanburyi has had a long history of use as the traditional dye as well as a complementary and alternative medicine. The antitumor activities of gamboge have been well demonstrated by inhibiting the growth and progression of cancer cells both in vitro and in vivo. In order to further clarify the mode of action of gamboge, there are three key questions needed to be answered, including what's in gamboge? How do the chemical components from gamboge work on cancer cells? How do biological systems work on the chemical components from gamboge after administration? In this review, we summarize the explorations of the answers toward these questions according to the recent progress in both of chemistry and biology research of gamboge. In addition, the implication in the future research and discovery of the caged G. xanthones as anticancer agents is also discussed.

Design, synthesis, and biological activities of histone deacetylase inhibitors with diketo ester as zinc binding group / 药学学报

Histone deacetylases (HDACs) inhibition causes hyperacetylation of histones leading to growth arrest, differentiation and apoptosis of tumor cells, representing a new strategy in cancer therapy. Many of previously reported HDACs inhibitors are hydroxamic acid derivatives, which could chelate the zinc ion in the active site in a bidentate fashion. However, hydroxamic acids occasionally have produced problems such as poor pharmacokinetics, severe toxicity and low selectivity. Herein we describe the identification of a new series of non-hydroxamate HDACs inhibitors bearing diketo ester moieties as zinc binding group. HDACs inhibition assay and antiproliferation assays in vitro against multiple cancer cell lines were used for evaluation. These compounds displayed low antiproliferative activity against solid tumor cells, while good antiproliferative activity against human leukemic monocyte lymphoma cell line U937. Compound CPUYS707 is the best with GI50 value of 0.31 micromol x L(-1) against U937 cells, which is more potent than SAHA and MS-275. HDACs inhibition activity of these compounds is lower than that expected, further evaluation is needed.

The research practice of anti-arrhythmic agents targeting on potassium ion channel / 药学学报

Due to the complicated pathogenesis of cardiac arrhythmia, the safe and effective therapeutic strategies for cardiac arrhythmia remain an urgent medical problems in the recent years. In this paper, we introduced the research practice of anti-arrhythmic agents targeting on potassium ion channel. The research progress of anti-arrhythmic agents in up-to-date literatures were also reviewed and prospected.

Recent advances in the structure-activity relationship study of small-molecule sodium channel blockers with analgesic effects / 药学学报

Pain is one of the common clinical symptom, previous studies have implicated sodium channels as a key constituent in pain signaling. Sodium channel blockers with efficient sodium channel blockade effect play an important role in analgesic treatment. However, most drugs used in clinic have many drawbacks and can not meet the demand of the clinical use. Therefore, for the development of new generation of sodium channel blockers, it is of great significance to find small molecule sodium channel blocking lead compounds with novel chemical scaffolds and new structures, sodium channel blocking activity and structure-activity relationship are discussed in detail, and current problems and trends in future research are also emphasized.

Synthesis and anti-histamine release activity of phenyl tetrazole compounds / 药学学报

Ongoing effort to find novel antiasthmatic drugs led to the design and synthesis of a series of compounds bearing phenyl tetrazole group based on the SAR study. The important intermediate 3-(1H-tetrazol-5-yl) benzenamine was synthesized from m-nitroaniline via cyclization and hydrogenation. Followed by amidation, eight new target compounds were obtained. The structures of these compounds were confirmed with 1H NMR, ESI-MS and elemental analysis. Their non-specific and specific anti-histamine effects in the mast cell were determined. Compound NP03 could inhibit non-specific histamine release induced by compound 48/80 in mast cell of SD rats.

Synthesis and biological evaluation of 3-quinolinecarbonitrile-7-amide derivatives / 药学学报

A series of N-(3-cyano-6-methyl-4-anilinoquinoline-7-yl) amide derivatives 13a-13n have been synthesized, their structures were confirmed with 1H NMR, EI-MS, IR and elemental analysis. Antitumor activities of all the synthesized compounds in vitro were tested with MTT. Compound 13j showed better than or equal antitumor activity on Bosutinib and EKB-569.

The design, synthesis and anticancer activity of 4-heteroarylamino-3-cyanoquinolines as dual inhibitors of c-Src and iNOS / 药学学报

Because c-Src and iNOS are key regulatory enzymes in tumorigenesis, a new series of 4-heterocycle amine-3-quinolinecarbonitriles as potent dual inhibitors of both enzymes were designed, synthesized and evaluated as multiple targets agents in cancer therapy. All compounds were evaluated by two related enzyme inhibition assays and an anti-proliferation assay in vitro. The results showed that most compounds inhibited c-Src and iNOS well. The best compound 33 inhibited both enzymes with the IC50 values of 0.0484 micromol x L(-1) and 34.5 micromol x (-1), respectively. Some of the compounds also showed moderate anti-proliferation activities at 10 micromol x L(-1) against colon cancer HT-29 and liver cancer HepG2 cell lines.

Effects of CPUY013, a novel Topo I inhibitor, on human gastric adenocarcinoma BGC823 cells in vitro and in vivo / 药学学报

Antitumor activity and the mechanism of CPUY013, a novel Topo I inhibitor, on gastric adenocarcinoma BGC823 cells were studied in vitro and in vivo. The proliferation was investigated by MTT assay and colony formation assay. Apoptosis was determined by both dual fluorescence staining with AO and EB and DNA agarose gel electrophoresis analysis methods. Nude mice model of BGC823 xenograft tumor was established by subcutaneous inoculation. The suppression activity of the CPUY013 by intragastric administration on xenograft mice model was detected. The change of cell cycle was studied by flow cytometry assay. The expressions of Topo I, widetype p53, active caspase-3, bcl-2 and bax proteins were analyzed by Western blotting assay. Results showed that CPUY013 could inhibit BGC823 cell proliferation at a certain range of dose. The flow cytometry analysis showed that CPUY013 and topoecan (TPT) led to a decrease in the proportion of G1 phase cells and an increase in the proportion of S phase cells, suggesting that they arrested the transition of tumor cells from S phase to G2 phase. The sub-G1 group was analyzed by flow cytometry. Compared with control, after 48 h treatment with CPUY013 or TPT, the sub-G1 group significantly increased in a dose-dependent manner. CPUY013 and TPT induced apoptosis in tumor cells. Cells treated with CPUY013 for 48 h were stained with AO/EB mixture. Then the cells were observed under fluorescence microscope. And it was found that early and late apoptosis cells were identified by perinuclear condensation of chromatin stained by AO/EB, respectively. Necrotic cells were identified by uniform labeling with EB. With the increase of concentration of CPUY013 and TPT, these morphological changes under the fluorescence microscope become clearer, indicating that the proportion of apoptosis cells increased gradually. By using JC-1 kit, loss of deltapsim was also detected in BGC823 cells treated with CPUY013 and TPT, which represent mitochondria function. And characteristic DNA ladder was observed apparently in BGC823 cells treated with CPUY013. When the xenograft tumor mice were treated with 150 mg x kg(-1) CPUY013, the tumor growth inhibition rate was 62.1%. The expression of bax and p53 proteins increased significantly and bcl-2 and bcl-2/bax decreased after the treatment of the CPUY013. The CPUY013 down-regulated Topo I protein expression and up-regulated active caspase-3 protein expression. The novel Topo I inhibitor CPUY013 can significantly suppress the growth of BGC823 xenograft tumor in vivo and inhibit the proliferation by inducing apoptosis of BGC823 cells in vitro.

Synthesis and biological evaluation of tetrahydro-beta-carline derivatives / 药学学报

Kinesin spindle protein (KSP/Eg5) is essential for the formation and maintenance of bipolar spindles during mitosis. Inhibition of this protein leads to cell cycle arrest and apoptosis without interfering other microtubule-dependent processes. Therefore, it is a potential target in cancer therapy. Here, a series of tetrahydro-beta-carboline derivatives 5a - k were synthesized as kinesin spindle protein inhibitor. Their structures were confirmed with 1H NMR, ESI-MS and elemental analysis. The synthesized compounds were evaluated for their inhibition of KSP.