• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.253.2-253.2
• /
• 2002

Apicidin. a natural product HDAC inhibitor. is recently isolated from Fusarium sp. at Merk Research Laboratories, induces therapeutic applications as a broad spectrum antiprotozoal agent to muti-drug resistant malaria and a potential antitumor agent. The biological activity of apicidin appears to be apicocomplexan HDAC at low nanomolar concentrations. (omitted)

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 2001.11a
• /
• pp.110-110
• /
• 2001

Histone deacetylase(HDAC), a neuclear enzyme that regulates gene trascription and the assembly of newly synthesized chromatin, has received much attention in recent literature. The explosion of activity in this field has yielded the cloning of a mammalian gene which encodes a complementary histone acetyl trasferases. Several cyclic tetrapeptide inhibitors of HDAC has been reported to affect the hyperacetylation of mammalian and plant histones. Apicidin, a natural product HDAC inhibitor recently isolated at Merck Research Laboratories, induces therapeutic applications as a broad spectrum antiprotozoal agent to multi-drug resistant malaria and a potential antitumor agnet. The biological activity of apicidin appears to be attributable to inhibition of apicocomplexan HDAC at low nanomolar concentrations.

• Biomolecules & Therapeutics
• /
• v.26 no.6
• /
• pp.591-598
• /
• 2018

Epigenetic silencing is considered to be a major mechanism for loss of activity in tumor suppressors. Reversal of epigenetic silencing by using inhibitors of DNA methyltransferase (DNMT) or histone deacetylases (HDACs) such as 5-Aza-CdR and FK228 has shown to enhance cytotoxic activities of several anticancer agents. This study aims to assess the combinatorial effects of genesilencing reversal agents (5-Aza-CdR and FK228) and oxaliplatin in gastric cancer cells, i.e., Epstein-Barr virus (EBV)-negative SNU-638 and EBV-positive SNU-719 cells. The doublet combinatorial treatment of 5-Aza-CdR and FK228 exhibited synergistic effects in both cell lines, and this was further corroborated by Zta expression induction in SNU-719 cells. Three drug combinations as 5-Aza-CdR/FK228 followed by oxaliplatin, however, resulted in antagonistic effects in both cell lines. Simultaneous treatment with FK228 and oxaliplatin induced synergistic and additive effects in SNU-638 and SNU-719 cells, respectively. Three drug combinations as 5-Aza-CdR prior to FK228/oxaliplatin, however, again resulted in antagonistic effects in both cell lines. This work demonstrated that efficacy of doublet synergistic combination using DNMT or HDACs inhibitors can be compromised by adding the third drug in pre- or post-treatment approach in gastric cancer cells. This implies that the development of clinical trial protocols for triplet combinations using gene-silencing reversal agents should be carefully evaluated in light of their potential antagonistic effects.

• Archives of Pharmacal Research
• /
• v.24 no.5
• /
• pp.455-465
• /
• 2001

The highly potent cytotoxic DNA-DNA cross-linker consists of two cyclopropa[c]pyrrolo[3,4-3]indol-4(5H)-ones insoles [(+)-CPI-I] joined by a bisamido pyrrole (abbreviated to "Pyrrole"). The Pyrrole is a synthetic analog of Bizelesin, which is currently in phase II clinical trials due to its excellent in vivo antitumor activity. The Pyrrole has 10 times more potent cytotoxicity than Bizelesin and mostly form DNA-DNA interstrand cross-links through the N3 of adenines spaced 7 bp apart. The Pyrrole requires a centrally positioned GC base pair for high cross-linking reactivity (i.e., $5^1$-T$AT_2$A*-$3^1$), while Bizelesin prefers purely AT-rich sequences (i.e., $5^1$-T$AT_4$A*-$3^1$, where /(equation omitted) represents the cross-strand adenine alkylation and A* represents an adenine alkylation) (Park et al., 1996). In this study, the high-field $^1$H-NMR and rMD studies are conducted on the 1 1-mer DNA duplex adduct of the Pyrrole where the 5′(equation omitted)TAGTTA*-3′sequence is cross-linked by the drug. A severe structural perturbation is observed in the intervening sequences of cross-linking site, while a normal B-DNA structure is maintained in the region next to the drug-modified adenines. Based upon these observations, we propose that the interplay between the bisamido pyrrole unit of the drug and central C/C base pair (hydrogen-bonding interactions) is involved in the process of cross-linking reaction, and sequence specificity is the outcome of those interactions. This study suggests a mechanism for the sequence specific cross-linking reaction of the Pyrrole, and provides a further insight to develop new DNA sequence selective and distortive cross-linking agents.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.1
• /
• pp.23-29
• /
• 2015

Background: Current cancer therapy mainly focuses on identifying novel targets crucial for tumorigenesis. The FoxM1 is of preference as an anticancer target, due to its significance in execution of mitosis, cell cycle progression, as well as other signal pathways leading to tumorigenesis. FoxM1 is partially regulated by oncoproteins or tumor suppressors, which are often mutated, lost, or overexpressed in human cancer. Since sustaining proliferating signaling is an important hallmark of cancer, FoxM1 is overexpressed in a series of human malignancies. Alarge-scale gene expression analysis also identified FoxM1 as a differentially-expressed gene in most solid tumors. Furthermore, overexpressed FoxM1 is correlated with the prognosis of cancer patients, as verified in a series of malignancies by Cox regression analysis. Thus, extensive studies have been conducted to explore the roles of FoxM1 in tumorigenesis, making it an attractive target for anticancer therapy. Several antitumor drugs have been reported to target or inhibit FoxM1 expression in different cancers, and down-regulation of FoxM1 also abrogates drug resistance in some cancer cell lines, highlighting a promising future for FoxM1 application in the clinic.

• Mycobiology
• /
• v.38 no.2
• /
• pp.144-148
• /
• 2010

$\beta$-Glucans have been known to exhibit antitumor activities by potentiating host immunity by an unknown mechanism. The C-type lectin dectin-1, a $\beta$-glucan receptor, is found on the macrophage and can recognize various $\beta$-glucans. Previously, we demonstrated the presence of $\beta$-glucan receptor, dectin-1, on the Raw 264.7 cells as well as on murine mucosal organs, such as the thymus, the lung, and the spleen. In order to investigate immunopotentiation of innate immunity by $\beta$-glucan, we stimulated a murine macrophage Raw 264.7 cell line with $\beta$-glucans from Pleurotus ostreatus, Saccharomyces cerevisiae, and Laminaria digitata. Then, we analyzed cytokines such as tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-6 by reverse transcription-polymerase chain reaction (RT-PCR). In addition we analyzed gene expression patterns in $\beta$-glucan-treated Raw 264.7 cells by applying total mRNA to cDNA microarray to investigate the expression of 7,000 known genes. When stimulated with $\beta$-glucans, the macrophage cells increased TNF-$\alpha$ expression. When co-stimulation of the cells with $\beta$-glucan and lipopolysaccharide (LPS), a synergy effect was observed by increased TNF-$\alpha$ expression. In IL-6 expression, any of the $\beta$-glucans tested could not induce IL-6 expression by itself. However, when co-stimulation occurred with $\beta$-glucan and LPS, the cells showed strong synergistic effects by increased IL-6 expression. Chip analysis showed that $\beta$-glucan of P. ostreatus increased gene expressions of immunomodulating gene families such as kinases, lectin associated genes and TNF-related genes in the macrophage cell line. Induction of TNF receptor expression by FACS analysis was synergized only when co-stimulated with $\beta$-glucan and LPS, not with $\beta$-glucan alone. From these data, $\beta$-glucan increased expressions of immunomodulating genes and showed synergistic effect with LPS.

• Integrative Medicine Research
• /
• v.3 no.2
• /
• pp.67-73
• /
• 2014

Background: The transcription factor signal transducer and activator of transcription 3 (Stat3)is constitutively activated in many human cancers. It promotes tumor cell proliferation,inhibits apoptosis, induces angiogenesis and metastasis, and suppresses antitumor hostimmune responses. Therefore, Stat3 has emerged as a promising molecular target for cancertherapies. In this study, we evaluated the Stat3-suppressive activity of 38 herbal medicinestraditionally used in Korea.Methods: Medicinal herb extracts in 70% ethanol were screened for their ability to suppressStat3 in the A549 human lung cancer cell line. A Stat3-responsive reporter assay system wasused to detect intracellular Stat3 activity in extract-treated cells, and Western blot analyseswere performed to measure the expression profiles of Stat3-regulated proteins.Results: Fifty percent of the 38 extracts possessed at least mild Stat3-suppressive activities(i.e., activity less than 75% of the vehicle control). Ethanol extracts of Bupleurum falcatumL., Taraxacum officinale Weber, Solanum nigrum L., Ulmus macrocarpa Hance, Euonymus alatusSieb., Artemisia capillaris Thunb., and Saururus chinensis (Lour.) Baill inhibited up to 75% of thevehicle control Stat3 activity level. A549 cells treated with these extracts also had reducedBcl-xL, Survivin, c-Myc, and Mcl-1 expression.Conclusion: Many medicinal herbs traditionally used in Korea contain Stat3 activity-suppressing substances. Because of the therapeutic impact of Stat3 inhibition, these resultscould be useful when developing novel cancer therapeutics from medicinal herbs.

• Toxicological Research
• /
• v.16 no.1
• /
• pp.47-52
• /
• 2000

To evaluate the renal toxicity of the antitumor agent, 1-(N-methyl) piperazinyl-3-phenyl-isoquinoline(CWJ-$\alpha$-5), rats were terated with CWJ-$\alpha$-5 (acute : 100mg/kg, i.p., single and subacute : 10mg/kr, i.p., daily for 7 days). The changes in the body weights, water consumption, kidney weights and urine volume after and during the treatment were observed. The concentrations of urinary creatinine, the activities of N-acetyl-$\beta$-D-glucosaminidase (NAG), alanine aminopeptidase (AAP), $\gamma$-glutamyl transpeptidase ($\gamma$-GT) and lactate dehydrogenase (LDH) in 24 hr urine were also determined. The body weight and water consumption were decreased after the acute and subacute administration. However, the excretion of urine was not changed except the 1 day after the acute treatment. The excretion of creatinine was significantly decreased from 1 day after acute administration and continuously decreased. Also the excretion of creatinine was decreased during subacute administration. However, the protein excretion did not changed in both treatment. Those indicate that CWJ-$\alpha$-5 might decrease the metabolic rate of muscle. The urinary activities of NAG, AAP, $\gamma$-GT, and LDH were significantly affected by the drug treatment. The urinary activities of NAG, AAP and $\gamma$-GT were significantly increased 1 and 3 days after the acute administration and then returned to the control value. However, the urinary activities of LDH were increased 7 days after acute treatment. During subacute treatment, the urinary activities of $\gamma$-GT were not changed. However, the urinary activities of NAG, AAP and LDH were only significantly increased after the third administration. These results indicate that either the high acute dose or the subacute administration with low dose of the compound might induce a temporal damage in the kidney cells.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.9
• /
• pp.3901-3906
• /
• 2014

Aim: The purpose of this study was to investigate anti-tumor effects and safety of DH332, a new ${\beta}$-carboline alkaloids derivatives in vitro and in vivo. Materials and Methods: The effects of DH332 on human (RAMOS RA.1) and mouse (J558) B lymphoma cell lines were detected using a CCK-8 kit (Cell Counting Kit-8), and apoptosis was detected by flow cytometry with PI/annexinV staining. Western blotting was used to detected caspase-3 and caspase-8. Neurotoxic and anti-tumor effects were evaluated in animal experiments. Results: DH332 exerts a lower neurotoxicity compared with harmine. It also possesses strong antitumor effects against two B cell lymphoma cell lines with low $IC_{50s}$. Moreover, DH332 could inhibit the proliferation and induce the apoptosis of RAMOS RA.1 and J558 cell lines in a dose-dependent manner. Our results suggest that DH332 triggers apoptosis by mainly activating the caspase signaling pathway. In vivo studies of tumor-bearing BALB/c mice showed that DH332 significantly inhibited growth of J558 xenograft tumors. Conclusions: DH332 exerts effective antitumor activity in vitro and in vivo, and has the potential to be a promising drug candidate for lymphoma therapy.

• Journal of Pharmacopuncture
• /
• v.22 no.4
• /
• pp.269-278
• /
• 2019

Objectives: Naesohwangryeon-tang (NHT) is a type of traditional herbal formula, however, little is known about its antitumor activity. In this study, the antitumor properties of NHT was evaluated in human lung adenocarcinoma cells. Methods: To check the inhibitory effect of NHT, MTT assay was performed. Cell cycle analysis and detection of ROS production were conducted by flow cytometry. To evaluate the signaling pathway, Western blotting was conducted. Results: Our results showed that the decrease of cell proliferation by NHT stimulation occurred more significantly in A549 cells than in NCI-H460 cells. In addition, NHT-induced apoptosis was associated with the activation of caspases and production of reactive oxygen species (ROS). NHT-induced apoptosis was attenuated after pretreatments with z-VAD-fmk or N-acetylcysteine, suggesting that NHT-induced apoptosis was caspaseand ROS-dependent. Interestingly, NHT treatment led to the development of autophagic vesicular organelles and upregulation of several autophagy-related genes. The pretreatment of bafilomycin A1 decreased apoptosis slightly but increased cell viability in the presence of NHT. Conclusion: These findings indicated that NHT induces both apoptosis and cell-protective autophagy in human lung cancer cells. This data suggests that NHT might be a novel herbal drug for lung cancer.