• Toxicological Research
• /
• v.19 no.3
• /
• pp.197-203
• /
• 2003

Apicidin, a histone-deacetylase inhibitor, has been successfully used to inhibit the growth of cancer cells. In this study, the apoptotic potential and mechanistic insights of apicidin were investigated in human myeloid leukemia U937 cells. Treatment of U937 cells with apicidin resulted in a decrease of cell viability with apoptotic characteristics, including chromatin condensation and ladder-pattern fragmentation of genomic DNA. Apicidin converted the procaspase-3 protease to catalytically active effector protease, resulting in subsequent cleavage of poly (ADP-ribose) polymerase (PARP) and inhibitor of caspase-activated deoxyribonuclease (ICAD). In addition, apicidin induced the activation of caspase-9 protease and the cytosolic release of mitochondrial cytochrome c with mitochon-drial membrane potential transition. Moreover, apicidin transiently increased the expression of Fas and Fas ligand proteins. Taken together, the results suggest that apicidin induces apoptosis of U937 cells through activation of intrinsic caspase cascades and Fas/FasL system with mitochondrial dysfunction.

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.188.1-188.1
• /
• 2003

The antiparasitic agent apicidin, which was recently isolated from cultures of Fusarium Pallidoroseum, belongs to a rare group of cyclictetrapeptide fungal metabolites. Apicidin inhibits protozoal HDAC and is orally active against Plasmodium berghei malaria in mice. The biological activity of apicidin appears to be attributable to inhibition of apicomplexan HDAC at low nanomolar concentrations. In the present, we have worked about the synthesis of new apicidin derivatives and discovered that apicidin and some derivatives have mild antitumor activity. (omiited)

• The Plant Pathology Journal
• /
• v.24 no.4
• /
• pp.417-422
• /
• 2008

Apicidin is a cyclic tetrapeptide produced by some Fusarium species and is known to inhibit Apicomplexan histone deacetylase. The goals of this study were to determine species identity of Fusarium isolate KCTC16676, an apicidin producer, to improve a method for apicidin extraction, and to test phytotoxicity of apicidin and its analogs. We compared sequences of the translation elongation factor 1-alpha (TEF) gene in KCTC16676 with those from isolates representing diverse Fusarium species, which showed that KCTC16676 belongs to the F. semitectum-F. equiseti species complex. To enhance apicidin production, after culturing isolate KCTC16676 on a wheat medium for 3 weeks at $25^{\circ}C$, the culture was extracted with chloroform. Apicidins were purified through a reverse phase $C_{18}$ silica gel column, resulting in 5 g of apicidin, 200 mg of apicidin A, and 300 mg of apicidin $D_2$ from 4 kg of wheat cultures; this represents a significant yield improvement from a previous method, offers more materials to study the modes of its action, and facilitates the elucidation of the apicidin biosynthesis pathway. Apicidin and apicidin $D_2$ showed phytotoxicity on both seedlings and 2-week-old plants of diverse species, and weeds were more sensitive to apicidins than vegetables

• Biomolecules & Therapeutics
• /
• v.17 no.1
• /
• pp.17-24
• /
• 2009

Histone deacetylase (HDAC) inhibitors are a promising class of anticancer agents that inhibit cancer cell growth in vitro and in vivo. Previous report has shown that apicidin inhibited SK-OV-3 cells proliferation and down-regulation of cyclin B1 and CDK1, and up-regulation of $p21^{WAF1}$ and p27. However, the mechanism of apicidin-mediated apoptotic cell death is not clearly understood. For this study, we investigated the mechanism of apoptotic pathway induced by apicidin in human ovarian cancer cell. We found that SK-OV-3 cells treated with apicidin caused an increase in the percentage of cells in the G2/M phase, which preceded apoptosis characterized by the appearance of cells with sub-G1 population. To further investigate the mechanism of apoptosis induction by apicidin, we measured TUNEL assay, poly-ADP ribose polymerase (PARP) cleavage, and caspase activity in SK-OV-3 cells treated with apicidin for 48 h. Apicidin significantly enhanced apoptosis as measured by TUNEL positive apoptotic cells, PARP cleavage, and increased Bax/Bcl-2 ratio. Induction of apoptosis was confirmed by the release of cytochrome c to cytosol. Our data suggest that apicidin-induced apoptosis in SK-OV-3 cells was accompanied by caspase-3 activation and the increase in Bax/Bcl-2 ratio. These data suggest that apicidin may be effective in the treatment of ovarian cancer through activation of intrinsic apoptotic pathway.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.310.1-310.1
• /
• 2003

SD-2007 ia an apicidin analogue, possessing a potent histone deacetylase inhibiting activity. A rapid and senstive LC/MS method was developed for the determination of SD-2007 and its major active metabolite. apicidin. in rat serum. SD-2007 and apicidin was extracted by liquid-liquid extraction using methyl t-butyl ether. SD-2007 and apicidin were monitored in a SIM mode at m/z of 679 and 622, respectively. (omitted)

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.244.2-244.2
• /
• 2003

The objective of this study was to characterize the absorption and pharmacokinetic disposition of novel cyclic tetrapeptide, apicidin, in rats. Apicidin was administered to SD rats by i.v. bolus injection (1,2 or 4 mg/kg) and oral gavages (10 mg/kg). Serum levels of apicidin were monitored by LC/MS over 8 hours following each administration. Upon i.v. injection, serum levels of apicidin were best fit by a multi-exponential equation. The t$\frac{1}{2}$. Cl$\sub$s/ and V$\sub$ss/ ranged from 0.9-1.1 hr, 52.8-56.5 ml/min/kg, and 2.6-2.7 L/kg, respectively. (omitted)

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.323.1-323.1
• /
• 2002

Apicidin ［cyclo(N-O-methyl-l -tryptophanyl-L -isoleucinyl-D-pipecolinyl-L-2-amino-8-oxodecano y)］. a histone deacetylase inhibitor. has been shown to cause growth arrest and morphological change of cancer cells. resulting from the alternation of protein expression. such as p21WAF1/Cip1 and gelsolin. However. proteome of altered by apicidin are poorly studied. In this study. we used a functional proteornics approach to identify the proteome altered by apicidin in Hela cells at 24hr post-treatment. (omitted)

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.323.2-323.2
• /
• 2002

We previously reported that apicidin induces apoptosis through selective induction of Fas/Fas ligand. resulting in the release of cytochrome C from mitochondria to the cytosol and subsequent activation of caspase-9 and \ulcorner However. we observed that apicidin did not induce the apoptosis in a specific cell line. such as HeLa. which was characterized by nuclear DNA fragmentation. On the basis of these facts, we tested whether JNK activation is involved in cell death induced by apicidin. (omitted)

• The Korean Journal of Physiology and Pharmacology
• /
• v.27 no.4
• /
• pp.407-416
• /
• 2023

The regeneration of myocardium following acute circulatory events remains a challenge, despite numerous efforts. Mesenchymal stem cells (MSCs) present a promising cell therapy option, but their differentiation into cardiomyocytes is a time-consuming process. Although it has been demonstrated that PSME4 degrades acetyl-YAP1, the role of PSME4 in the cardiac commitment of MSCs has not been fully elucidated. Here we reported the novel role of PSME4 in MSCs cardiac commitment. It was found that overnight treatment with apicidin in primary-cultured mouse MSCs led to rapid cardiac commitment, while MSCs from PSME4 knock-out mice did not undergo this process. Cardiac commitment was also observed using lentivirus-mediated PSME4 knockdown in immortalized human MSCs. Immunofluorescence and Western blot experiments revealed that YAP1 persisted in the nucleus of PSME4 knockdown cells even after apicidin treatment. To investigate the importance of YAP1 removal, MSCs were treated with shYAP1 and apicidin simultaneously. This combined treatment resulted in rapid YAP1 elimination and accelerated cardiac commitment. However, overexpression of acetylation-resistant YAP1 in apicidin-treated MSCs impeded cardiac commitment. In addition to apicidin, the universal effect of histone deacetylase (HDAC) inhibition on cardiac commitment was confirmed using tubastatin A and HDAC6 siRNA. Collectively, this study demonstrates that PSME4 is crucial for promoting the cardiac commitment of MSCs. HDAC inhibition acetylates YAP1 and facilitates its translocation to the nucleus, where it is removed by PSME4, promoting cardiac commitment. The failure of YAP1 to translocate or be eliminated from the nucleus results in the MSCs' inability to undergo cardiac commitment.

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.323.3-324
• /
• 2002

Histone deacetylases (HDAC) activity is associated generally with transcriptional repression. We have reported previously that apicidin. a histione deacetylase inhibitor. inhibited the proliferation of tumor cells via induction of p21 WAF/C1P1. We extended our study to identify the effect of apicidin on the expression of other cell cycle regulatory protein. such as cyclin E. a critical regulator of the transition from G1 into S phase. (omitted)