• BMB Reports
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• v.44 no.12
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• pp.811-815
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• 2011

Inhalational anthrax is caused by B. anthracis, a virulent sporeforming bacterium which secretes anthrax toxins consisting of protective antigen (PA), lethal factor (LF) and edema factor (EF). LF is a Zn-dependent metalloprotease and is the main determinant in the pathogenesis of anthrax. Here we report the identification of a lead small-molecule inhibitor of anthrax lethal factor by screening an available synthetic small-molecule inhibitor library using fluorescence-based high-throughput screening (HTS) approach. Seven small molecules were found to have inhibitory effect against LF activity, among which SM157 had the highest inhibitory activity. All theses small molecule inhibitors inhibited LF in a noncompetitive inhibition mode. SM157 and SM167 are from the same family, both having an identical group complex, which is predicted to insert into S1' pocket of LF. More potent small-molecule inhibitors could be developed by modifying SM157 based on this identical group complex.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1286-1289
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• 2013

• Toxicological Research
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• v.24 no.2
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• pp.93-100
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• 2008

Targeting protein kinases has been active area in drug discovery. The c-Jun N-terminal kinases(JNKs) have also been target for development of novel therapy in various diseases, since the roles of JNK signaling in pathological conditions were revealed in studies using jnk-deficient mice. Small molecule inhibitors and peptide inhibitors are identified for therapeutic intervention of JNK signaling pathway. SP-600125, an anthrapyrazole small molecule inhibitor for JNK with high potency and selectivity has been widely used for dissecting JNK signaling pathway. CC-401 is the first JNK inhibitor that went into clinical trial for inflammation and leukemia. Inhibitor for mixed lineage kinase (MLK), CEP-1347 also negatively regulates JNK signaling, and tried for potential use in Parkinson's disease. Cell-permeable peptide inhibitor D-JNKI-1 is being developed for the treatment of hearing loss. The current status of these JNK inhibitors and safety issue is discussed in the minireview.

• Oncology Letters
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• v.41 no.1
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• pp.361-368
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• 2019

Gliomas, the most highly malignant central nervous system tumors, are associated with an extremely poor patient survival rate. Given that gliomas are derived from mutations in glial precursor cells, a considerable number of them strongly react with glial precursor cell-specific markers. Thus, we investigated whether malignant gliomas can be converted to glial cells through the regulation of endogenous gene expression implicated in glial precursor cells. In the present study, we used three small-molecule compounds, [cyclic adenosine monophosphate (cAMP) enhancer, a mammalian target of rapamycin (mTOR) inhibitor, and a bromodomain and extra-terminal motif (BET) inhibitor] for glial reprogramming. Small-molecule-induced gliomas (SMiGs) were not only transformed into exhibiting a glial-specific morphology, but also showed positive reactions with glial-specific markers such as glial fibrillary acidic protein (GFAP), 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) and anti-oligodendrocyte (RIP). A microarray analysis indicated that SMiGs exhibited a marked increase in specific gene levels, whereas that of a malignant cancer-specific gene was greatly decreased. Moreover, proliferation of the cells was markedly suppressed after the conversion of malignant glioma cells into glial cells. Our findings confirmed that malignant gliomas can be reprogrammed to non-proliferating glial cells, using a combination of small molecules, and their proliferation can be regulated by their differentiation. We suggest that our small-molecule combination (with forskolin, rapamycin and I-BET151) may be the next generation of anticancer agents that act by reprogramming malignant gliomas to differentiate into glial cells.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1405-1408
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• 2012

• Journal of the Korean Magnetic Resonance Society
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• v.18 no.1
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• pp.10-14
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• 2014

Hsp90 is a good drug target molecule that is involved in regulating various signaling pathway in normal cell and the role of Hsp90 is highly emphasized especially in cancer cells. Thus, much efforts for discovery and development of Hsp90 inhibitor have been continued and a few Hsp90 inhibitors targeting the N-terminal ATP binding site are being tested in the clinical trials. There are no metabolic signature molecules that can be used to evaluate the effect of Hsp90 inhibition. We previously found a potential C-domain binder named PPC1 that is a synthetic small molecule. Here we report the metabolomics study to find signature metabolites upon treatment of PPC1 compound in lung cancer cell line, A549 and discuss the potentiality of metabolomic approach for evaluation of hit compounds.

• Biomolecules & Therapeutics
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• v.19 no.4
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• pp.371-389
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• 2011

A new strategy for cancer therapy has emerged during the past decade based on molecular targets that are less likely to be essential in all cells in the body, therefore confer a wider therapeutic window than traditional cytotoxic drugs which mechanism of action is to inhibit essential cellular functions. Exceptional heterogeneity and adaptability of cancer impose significant challenges in oncology drug discovery, and the concept of complex tumor biology has led the framework of developing many anticancer therapeutics. Protein kinases are the most pursued targets in oncology drug discovery. To date, 12 small molecule kinase inhibitors have been approved by US Food and Drug Administration, and many more are in clinical development. With demonstrated clinical efficacy of bortezomib, ubiquitin proteasome and ubiquitin-like protein conjugation systems are also emerging as new therapeutic targets in cancer therapy. In this review, strategies of targeted cancer therapies with inhibitors of kinases and proteasome systems are discussed. Combinational cancer therapy to overcome drug resistance and to achieve greater treatment benefit through the additive or synergistic effects of each individual agent is also discussed. Finally, the opportunities in the future cancer therapy with molecularly targeted anticancer therapeutics are addressed.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2007-2010
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• 2015

A new chemical inhibitor against severe acute respiratory syndrome (SARS) coronavirus helicase, 7-ethyl-8-mercapto-3-methyl-3,7-dihydro-1H-purine-2,6-dione, was identified. We investigated the inhibitory effect of the compound by conducting colorimetry-based ATP hydrolysis assay and fluorescence resonance energy transfer-based double-stranded DNA unwinding assay. The compound suppressed both ATP hydrolysis and double-stranded DNA unwinding activities of helicase with IC₅₀ values of 8.66 ± 0.26 μM and 41.6 ± 2.3 μM, respectively. Moreover, we observed that the compound did not show cytotoxicity up to 80 μM concentration. Our results suggest that the compound might serve as a SARS coronavirus inhibitor.

• BMB Reports
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• v.43 no.11
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• pp.711-719
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• 2010

Kinomics is an emerging and promising approach for deciphering kinomes. Chemical kinomics is a discipline of chemical genomics that is also referred to as "chemogenomics", which is derived from chemistry and biology. Chemical kinomics has become a powerful approach to decipher complicated phosphorylation-based cellular signaling networks with the aid of small molecules that modulate kinase functions. Moreover, chemical kinomics has played a pivotal role in the field of kinase drug discovery as it enables identification of new molecular targets of small molecule kinase modulators and/or exploitation of novel functions of known kinases and has also provided novel chemical entities as hit/lead compounds. In this short review, contemporary chemical kinomics technologies such as activity-based protein profiling, T7 kinasetagged phages, kinobeads, three-hybrid systems, fluorescenttagged kinase binding assays, and chemical genomic profiling are discussed along with a novel allosteric Bcr-Abl kinase inhibitor (GNF-2/GNF-5) as a successful application of chemical kinomics approaches.

• BMB Reports
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• v.48 no.2
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• pp.121-126
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• 2015

Here we report a new chemical inhibitor against HIV-1 with a novel structure and mode of action. The inhibitor, designated as A1836, inhibited HIV-1 replication and virus production with a 50% inhibitory concentration ($IC_{50}$) of $2.0{\mu}M$ in an MT-4 cell-based and cytopathic protection antiviral assay, while its 50% cytotoxic concentration ($CC_{50}$) was much higher than $50{\mu}M$. Examination of the effect of A1836 on in vitro HIV-1 reverse transcriptase (RT) and integrase showed that neither were molecular targets of A1836. The characterization and re-infection assay of the HIV-1 virions generated in the presence of A1836 showed that the synthesis of early RT products in the cells infected with the virions was inhibited dose-dependently, due in part to abnormal protein formation within the virions, thus resulting in an impaired infectivity. These results suggest that A1836 might be a novel candidate for the development of a new type of HIV-1 inhibitor.