• 한국식물병리학회지
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• 제10권3호
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• pp.151-156
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• 1994

Pseudomonas fluorescens produces the antibiotic, 2,4-diacetylphloroglucinol (Phl), which promotes plant growth by inhibiting bacteria and fungi. Cosmids (genomic library) were mobilized into Phl-nonproducing mutants through the triparental matings with pRK2013 as the helper plasmid at the frequency of 8.37$\times$10-4. Complemented mutants that showed antibiotic activity were selected among about 2,000 transconjugants. The complemented mutants were confirmed by acquired drug resistances (kanamycin and tetracycline). The antibiotic substances of wild type and complemented mutants showed the most excellent anti-bacterial activity. Inhibitory effects of complemented P. fluorescens against phytopathogenic fungi were equal to the parental strain. Complemented mutant and wild type of P. fluorescens were causal microbes of fungal morphological abnormalities. Complemented mutants in potato dextrose agar supplemented with bromothymol blue also showed restoration of glucose utilization as wild type. Plasmids of complemented mutants were isolated from transconjugant sand transformed into competent cells of E. coli DH5$\alpha$. The plamid DNA was reisolated from transformed E. coli DH5$\alpha$.

• 한국균학회지
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• 제25권4호통권83호
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• pp.348-353
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• 1997

계피의 항진균활성을 검색한 결과 에테르 추출물이 우수한 활성을 나타내는 것으로 평가되어 계피 에테르의 추출물로부터 항진균물질 AF-001을 분리 정제하였으며 이를 동정한 결과 trans-cinnamaldehyde로 확인되었다. AF-001은 피부진균증의 원인 균주인 Tricophyton mentagrophytes, Microsporium gypseum, Epidermophyton floccosum, Cryptococcus neofomans, Aspergillus niger, Candida albicans와 Penicillium avellaneum에 대해 $38{\sim}79\;{\mu}g/ml$의 최소저지농도를 보였으며 imidazole계의 대표적인 항진균제인 Ketoconazole보다 광범위한 항균 스펙트럼을 보였다.

• The Korean Journal of Physiology and Pharmacology
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• 제14권5호
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• pp.331-336
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• 2010

In rapidly growing tumors, hypoxia commonly develops due to the imbalance between $O_2$ consumption and supply. Hypoxia Inducible Factor (HIF)-$1{\alpha}$ is a transcription factor responsible for tumor growth and angiogenesis in the hypoxic microenvironment; thus, its inhibition is regarded as a promising strategy for cancer therapy. Given that CamKII or PARP inhibitors are emerging anticancer agents, we investigated if they have the potential to be developed as new HIF-$1{\alpha}$-targeting drugs. When treating various cancer cells with the inhibitors, we found that a CamKII inhibitor, KN-62, effectively suppressed HIF-$1{\alpha}$ specifically in hepatoma cells. To examine the effect of KN-62 on HIF-$1{\alpha}$-driven gene expression, we analyzed the EPO-enhancer reporter activity and mRNA levels of HIF-$1{\alpha}$ downstream genes, such as EPO, LOX and CA9. Both the reporter activity and the mRNA expression were repressed by KN-62. We also found that KN-62 suppressed HIF-$1{\alpha}$ by impairing synthesis of HIF-$1{\alpha}$ protein. Based on these results, we propose that KN-62 is a candidate as a HIF-$1{\alpha}$-targeting anticancer agent.

• Toxicological Research
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• 제22권4호
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• pp.349-356
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• 2006

Diallyl disulfide (DADS), an oil-soluble organosulfur compound in garlic has been reported to suppress tumor growth and to induce apoptosis in cancer. In the present study, we investigated the effects of DADS on pulmonary metastasis of B16-F10 murine melanoma cells. DADS (i.p. 40 mg/kg) significantly (p<0.05) reduced the number of pulmonary metastatic nodules (48%) in experimental pulmonary metastasis assay. We also found that DADS inhibited adhesion, invasion and migration of B16-F10 melanoma cells in a dose-dependent manner. To study the antimetastatic potential of DADS, we performed the effects of DADS on matrix metalloproteinase activity. DADS significantly inhibited the expression of matrix metalloproteinase-2 activity in B16-F10 cells by gelatin zymography. These results suggest that DADS prevent metastasis in part through suppression of migration of B16-F10 melanoma cells by Inhibiting matrix metalloproteirase-2 responsible for degradation of extracellar matrix.

• 대한화학회지
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• 제62권2호
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• pp.106-112
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• 2018

Ice-binding proteins have an affinity for ice. They create a gap between the melting and freezing points by inhibiting the growth of ice, known as thermal hysteresis (TH). Interestingly, moderately active LeIBP and hyperactive FfIBP are almost identical in primary and tertiary structures, but differ in TH activity. The TH of FfIBP is tenfold higher than that of LeIBP, due to a subtle difference in their ice-binding motifs. To further evaluate the difference in TH, the interactions were investigated by ice-etching and molecular docking. Ice-etching showed that FfIBP binds to the primary and secondary prism, pyramidal, and basal planes; previously, LeIBP was found to bind to the basal and primary prism planes. Docking analysis using shape complementarity (Sc) showed that the hyperactive FfIBP had higher Sc values for all four ice planes than LeIBP, which is comparable with TH. Docking can be used to describe the hyperactivity of IBPs.

• Journal of Microbiology and Biotechnology
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• 제23권2호
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• pp.184-188
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• 2013

In the continued search for inhibitors of enoyl-acyl carrier protein (ACP) reductase, we found that four acylbenzenediol sulfate metabolites from Streptomyces sp. AN1761 potently inhibited bacterial enoyl-ACP reductases of Staphylococcus aureus, Streptococcus pneumoniae, and Mycobacterium tuberculosis. Their structures were identified as panosialins A, B, wA, and wB by MS and NMR data. They showed stronger inhibition against S. aureus FabI and S. pneumoniae FabK with $IC_{50}$ of 3-5 ${\mu}M$ than M. tuberculosis InhA with $IC_{50}$ of 9-12 ${\mu}M$. They also exhibited a stronger antibacterial spectrum on S. aureus and S. pneumoniae than M. tuberculosis. In addition, the higher inhibitory activity of panosialin wB than panosialin B on fatty acid biosynthesis was consistent with that on bacterial growth, suggesting that they could exert their antibacterial activity by inhibiting fatty acid synthesis.

• Biomolecules & Therapeutics
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• 제30권3호
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• pp.257-264
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• 2022

Colorectal cancer (CRC) is one of the most common malignant tumor. 5-FU is commonly used for the treatment of CRC. However, the development of drug resistance in tumor chemotherapy can seriously reduce therapeutic efficacy of 5-FU. Recent data show that FoxM1 is associated with 5-FU resistance in CRC. FoxM1 plays a critical role in the carcinogenesis and drug resistance of several malignancies. It has been reported that urushiol V isolated from the cortex of Rhus verniciflua Stokes is cytotoxic to several types of cancer cells. However, the underlying molecular mechanisms for its antitumor activity and its potential to attenuate the chemotherapeutic resistance in CRC cells remain unknown. Here, we found that urushiol V could inhibit the cell proliferation and induced S-phase arrest of SW480 colon cancer cells. It inhibited protein expression level of FoxM1 through activation of AMPK. We also investigated the combined effect of urushiol V and 5-FU. The combination treatment reduced FoxM1 expression and consequently reduced cell growth and colony formation in 5-FU resistant colon cancer cells (SW480/5-FUR). Taken together, these result suggest that urushiol V from Rhus verniciflua Stokes can suppress cell proliferation by inhibiting FoxM1 and enhance the antitumor capacity of 5-FU. Therefore, urushiol V may be a potential bioactive compound for CRC therapy.

• Nutrition Research and Practice
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• 제17권5호
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• pp.844-854
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• 2023

BACKGROUND/OBJECTIVES: Fucoidan, a polysaccharide content in brown algae, has been reported to inhibit the growth of cancer cells. The present study aimed to investigate the suppression effects of fucoidan on A549 non-small cell lung cancer cells migration. MATERIALS/METHODS: The anti-migratory activity of fucoidan in A549 cells was examined by wound healing assay and phalloidin-rhodamine staining in response to fucoidan (0-100 ㎍/mL) treatment for 48 h. Western blot analysis was performed to clarify the protein expressions relevant to migratory activity. RESULTS: Fucoidan (25-100 ㎍/mL) significantly suppressed A549 cells migration together with reduced the intensity of phalloidin-rhodamine which detect filopodia and lamellipodia protrusions at 48 h of treatment. The protein expression indicated that fucoidan significantly suppressed the phosphorylation of focal adhesion kinase (FAK), Src, and extracellular signal-related kinase (ERK). In addition, the phosphorylation of p38 in A549 cells was found to be increased. CONCLUSIONS: Our data conclude that fucoidan exhibits anti-migratory activities against lung cancer A549 cells mediated by inhibiting ERK1/2 and FAK-Src pathway.

• IMMUNE NETWORK
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• 제21권3호
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• pp.21.1-21.22
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• 2021

Myeloid-derived suppressor cells (MDSCs) have strong immunosuppressive activity and are morphologically similar to conventional monocytes and granulocytes. The development and classification of these cells have, however, been controversial. The activation network of MDSCs is relatively complex, and their mechanism of action is poorly understood, creating an avenue for further research. In recent years, MDSCs have been found to play an important role in immune regulation and in effectively inhibiting the activity of effector lymphocytes. Under certain conditions, particularly in the case of tissue damage or inflammation, MDSCs play a leading role in the immune response of the central nervous system. In cancer, however, this can lead to tumor immune evasion and the development of related diseases. Under cancerous conditions, tumors often alter bone marrow formation, thus affecting progenitor cell differentiation, and ultimately, MDSC accumulation. MDSCs are important contributors to tumor progression and play a key role in promoting tumor growth and metastasis, and even reduce the efficacy of immunotherapy. Currently, a number of studies have demonstrated that MDSCs play a key regulatory role in many clinical diseases. In light of these studies, this review discusses the origin of MDSCs, the mechanisms underlying their activation, their role in a variety of clinical diseases, and their function in immune response regulation.

• Journal of Microbiology and Biotechnology
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• 제34권2호
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• pp.240-248
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• 2024

In cancer treatment, multi-target approach has paid attention to a reasonable strategy for the potential agents. We investigated whether (E)-2-methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) phenol (MMPP) could exert an anticancer effect by dual-regulating VEGFR2 and PPARγ. MMPP showed modulating effects in TNBC type (MDA-MB-231 and MDA-MB-468) and luminal A type (MCF7) breast cancer cell lines. MMPP enhanced PPARγ transcriptional activity and inhibited VEGFR2 phosphorylation. MMPP-induced signaling by VEGFR2 and PPARγ ultimately triggered the downregulation of AKT activity. MMPP exhibited anticancer effects, as evidenced by growth inhibition, inducement of apoptosis, and suppression of migration and invasion. At the molecular level, MMPP activated pro-apoptotic proteins (caspase3, caspase8, caspase9, and bax), while inhibiting the anti-apoptotic proteins (bcl2). Additionally, MMPP inhibited the mRNA expressions of EMT-promoting transcription factors. Therefore, our findings showed molecular mechanisms of MMPP by regulating VEGFR2 and PPARγ, and suggested that MMPP has potential to treat breast cancer.