• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.202-214
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• 2015

Stimuli-responsive biomaterials that alter their function through sensing local molecular cues may enable technological advances in the fields of drug delivery, gene delivery, actuators, biosensors, and tissue engineering. In this research, pH-responsive hydrogel which is comprised of dimethylaminoethyl methacylate (DMAEMA) and 2-hydroxyethyl methacrylate (HEMA) was synthesized for the effective delivery of doxorubicin (Dox) to breast cancer cells. Cancer and tumor tissues show a lower extracellular pH than normal tissues. DMAEMA/HEMA hydrogels showed significant sensitivity by small pH changes and each formulation of hydrogels was examined by scanning electron microscopy, mechanical test, equilibrium mass swelling, controlled Dox release, and cytotoxicity. High swelling ratios and Dox release were obtained at low pH buffer condition, low cross-linker concentration, and high content of DMAEMA. Dox release was accelerated to 67.3% at pH 5.5 for 6-h incubation at $37^{\circ}C$, while it was limited to 13.8% at pH7.4 at the same time and temperature. Cell toxicity results to breast cancer cells indicate that pH-responsive DMAEMA/HEMA hydrogels may be used as an efficient matrix for anti-cancer drug delivery with various transporting manners. Also, pH-responsive DMAEMA/HEMA hydrogels may be useful in therapeutic treatment which is required a triggered release at low pH range such as gene delivery, ischemia, and diabetic ketoacidosis.

• Macromolecular Research
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• v.17 no.12
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• pp.1010-1014
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• 2009

Monodispersed microparticles with a poly(D,L-lactide-co-glycolide) (PLGA) core and a poly(ethyl 2-cyanoacrylate) (PE2CA) shell were prepared by Shirasu porous glass (SPG) membrane emulsification to reduce the initial burst release of doxorubicin (DOX). Solution mixtures with different weight ratios of PLGA polymer and E2CA monomer were permeated under pressure through an SPG membrane with $1.9\;{\mu}m$ pore size into a continuous water phase with sodium lauryl sulfate as a surfactant. Core-shell structured microparticles were formed by the mechanism of anionic interfacial polymerization of E2CA and precipitation of both polymers. The average diameter of the resulting microparticles with various PLGA:E2CA ratios ranged from 1.42 to $2.73\;{\mu}m$. The morphology and core-shell structure of the microparticles were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The DOX release profiles revealed that the microparticles with an equivalent PLGA:E2CA weight ratio of 1:1 exhibited the optimal condition to reduce the initial burst of DOX. The initial release rate of DOX was dependent on the PLGA:E2CA ratio, and was minimized at a 1:1 ratio.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.94-94
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• 1995

Aspalatone (APT)의 예상되는 항산화 작용을 검색하기 위하여 Doxorubicin(Dox.) 유발독성 (Dox.의 작용 발현 기전은 oxyradical 생성에 의해 매개됨)으로 인하여 변화되는 항산화 효소계 및 과산화지질 생성에 대하여 APT의 효과를 검색하고, 별도로 Hydroxyl radical 생성에 미치는 APT의 효능을 검정하기 위하여 ESR spin trapping technique을 이용하여 ㆍOH/DMPO ESR signal을 검정하여 아래의 결과를 얻었다. Dox 투여 2일 후에 생쥐 심장에서 얻어진 SOD-1의 보상성 유도는 APT 병용 투여로 억제되었고, Catalase 활성을 유도하였으나 MBA 치에는 유의한 변화가 나타나지 않았다. 반면에 간에서는 APT으로 인하여 GSH-PX가 현저히 유도되었고 (다른 항산화 효소에는 유의한 변화가 나타나지 않았음), MDA 치가 억제되었다. 한편 Fenton 반응동안 증가되었던 ㆍOH/DMPO ESR signal은 APT에 의해 억제되었다. 이상의 결과에서 APT의 항산화성 효능이 인정되지만, Dox. 및 APT 각각의 용량 및 노출 시간의 상관성, 그리고 생화학적인 결과에 대한 (미세)조직학적인 확인이 요구되며 각각의 실험군, 즉 aspirin, maltol에 대한 효능/효력 검정도 추가로 보완되어야 할 것으로 생각된다.

• KSBB Journal
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• v.20 no.3
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• pp.220-227
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• 2005

Doxorubicin is an anthracycline-family polyketide compound with a very potent anti-cancer activity, typically produced by Streptomyces peucetius. To understand the potential target biosynthetic genes critical for the doxorubicin everproduction, a doxorubicin-specific DNA microarray chip was fabricated and applied to reveal the growth-phase-dependent expression profiles of biosynthetic genes from two doxorubicin-overproducing strains along with the wild-type strain. Two doxorubicin-overproducing 5. peucetius strains were generated via over-expression of a dnrl (a doxorubicin-specific positive regulatory gene) and a doxA (a gene involved in the conversion from daunorubicin to doxorubicin) using a streptomycetes high expression vector containing a strong ermE promoter. Each doxorubicin-overproducing strain was quantitatively compared with the wild-type doxorubicin producer based on the growth-phase-dependent doxorubicin productivity as well as doxorubicin biosynthetic gene expression profiles. The doxorubicin-specific DNA microarray chip data revealed the early-and-steady expressions of the doxorubicin-specific regulatory gene (dnrl), the doxorubicin resistance genes (drrA, drrB, drrC), and the doxorubicin deoxysugar biosynthetic gene (dnmL) are critical for the doxorubicin overproduction in S. peucetius. These results provide that the relationship between the growth-phase-dependent doxorubicin productivity and the doxorubicin biosynthetic gene expression profiles should lead us a rational design of molecular genetic strain improvement strategy.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10705-10711
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• 2015

Oral cancer is one of the most common and lethal cancers in the world. Combination chemotherapy coupled with nanoparticle drug delivery holds substantial promise in cancer therapy. This study aimed to evaluate the efficacy and safety of two dosages of our novel pH and temperature sensitive doxorubicin-methotrexate-loaded nanoparticles (DOX-MTX NPs) with attention to the MMP-2 mRNA profile in a 4-nitroquinoline-1-oxide induced oral squamous cell carcinoma (OSCC) model in the rat. Our results showed that both IV and oral dosages of DOX-MTX NP caused significant decrease in mRNA levels of MMP-2 compared to the untreated group (p<0.003). Surprisingly, MMP-2 mRNA was not affected in DOX treated compared to cancer group (p>0.05). Our results indicated that IV dosage of MTX-DOX is more effective than free DOX (12 fold) in inhibiting the activity of MMP-2 in OSCCs (P<0.001). Furthermore, MMP-2 mRNA expression in the DOX-MTX treated group showed a significant relation with histopathological changes (P=0.011). Compared to the untreated cancer group, we observed no pathological changes and neither a significant alteration in MMP-2 amount in either of healthy controls that were treated with oral and IV dosages of DOX-MTX NPs whilst cancer group showed a high level of MMP-2 expression compared to healthy controls (p<0.001).Taking together our results indicate that DOX-MTX NPs is a safe chemotherapeutic nanodrug that its oral and IV forms possess potent anti-cancer properties on aggressive tumors like OSCC, possibly by affecting the expression of genes that drive tumor invasion and metastasis.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.179-184
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• 2014

Chemoresistance of breast cancer to doxorubicin is mediated mainly through activation of NF-kB and over expression of HER2. Curcumin and its analogues (PGV-0 and PGV-1) exert cytotoxic effects on T47D breast cancer cells. Suppression of NF-kB activation is suggested to contribute to this activity. The present study aimed to explore the effects of curcumin, PGV-0, and PGV-1 singly and in combination with doxorubicin on MCF-7/Dox cells featuring over-expression of HER2. In MTT assays, curcumin, PGV-0, and PGV-1 showed cytotoxicity effects against MCF-7/Dox with IC50 values of $80{\mu}M$, $21{\mu}M$, and $82{\mu}M$ respectively. These compounds increased MCF-7/Dox sensitivity to doxorubicin. Cell cycle distribution analysis exhibited that the combination of curcumin and its analogues with Dox increased sub G-1 cell populations. Curcumin and PGV-1 but not PGV-0 decreased localization of p65 into the nucleus induced by Dox, indicating that activation of NF-kB was inhibited. Molecular docking of curcumin, PGV-0, and PGV-1 demonstrated high affinity to HER2 at ATP binding site. This interaction were directly comparable with those of ATP and lapatinib. These findings suggested that curcumin, PGV-0 and PGV-1 enhance the Dox cytotoxicity to MCF-7 cells through inhibition of HER2 activity and NF-kB activation.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4223-4231
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• 2016

Background: Development of new apoptosis-inducing drugs is a promising trend in anticancer therapy. For this purpose several formamidinoderivatives of doxorubicin were synthesized. The aim of our study was to investigate effects of the five formamidinodoxorubicins in the ES-2 human ovarian clear cell carcinoma line, for comparison with data obtained previously for SKOV-3 human ovarian adenocarcinoma cells, to answer the question of whether and to what extent the histological cell type is a possible determinant of sensitivity to tested anthracyclines. Materials and Methods: In our experimental work the following methods were used: spectrophotometric assays with MTT; fluorimetric assays - double staining with Hoechst 33258 and propidium iodide (PI), measurement of caspase-3, -8, -9 activity, intracellular accumulation of DOX and analogues, estimation of drug uptake, mitochondrial transmembrane potential; flow cytometry - phosphatidylserine (PS) externalization with annexin V-FITC and PI fluorochromes. Results: Effects of the derivatives of doxorubicin were partially linked with the specific type of cancer cell although intracellular accumulation and cellular uptake of DOX and derivatives were similar in both. All of the investigated derivatives were considerably more cytotoxic than DOX. Formamidinodoxorubicins were able to induce caspase-dependent apoptotic cell death in both cell types. Conclusions: All new formamidine derivatives of DOX were able to induce caspase - dependent apoptosis in human ovarian cancer cell lines SKOV-3 and ES-2. Obtained results suggested that formamidine derivatives of DOX may be promising candidates for the prospective chemotherapeutic agents for the two different histological subtypes of ovarian cancer.

• BMB Reports
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• v.50 no.6
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• pp.335-340
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• 2017

Although doxorubicin (Dox)-induced oxidative stress is known to be associated with cytotoxicity, the precise mechanism remains unclear. Genotoxic stress not only generates free radicals, but also affects actin cytoskeleton stability. We showed that Dox-induced RhoA signaling stimulated actin cytoskeleton alterations, resulting in central stress fiber disruption at early time points and cell periphery cortical actin formation at a later stage, in HeLa cells. Interestingly, activation of a cofilin phosphatase, chronophin (CIN), was initially evoked by Dox-induced RhoA signaling, resulting in a rapid phosphorylated cofilin turnover leading to actin cytoskeleton remodeling. In addition, a novel interaction between CIN and $14-3-3{\zeta}$ was detected in the absence of Dox treatment. We demonstrated that CIN activity is quite contrary to $14-3-3{\zeta}$ binding, and the interaction leads to enhanced phosphorylated cofilin levels. Therefore, initial CIN activation regulation could be critical in Dox-induced actin cytoskeleton remodeling through RhoA/cofilin signaling.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4025-4030
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• 2012

Background and Objective: Cardiotoxicity and oxidative stress is a life-threatening side effect of doxorubicin (DOX). We investigate the effects of short-term exercise as therapeutic tool for improvement of cardioprotection against DOX-induced cardiotoxicity in the rat. Methods: Wistar males (weighing $257{\pm}28g$) were divided into six groups: (1) control+placebo (2) control+DOX $10mg.kg^{-1}$ (3) control+DOX $20mg.kg^{-1}$ (4) training+placebo (5) training+ DOX$10mg.kg^{-1}$ (6) training+DOX $20mg.kg^{-1}$. Cardiotoxicity was induced by DOX (10 and $20mg.kg^{-1}$). The rats in groups 4, 5 and 6 experienced treadmill running of 25 to $39min.day^{-1}$ and 15 to $17m.min^{-1}$, 5 days/wk for 3 wk. At the end of the endurance training program, rats in the 1 and 4 groups, in the 2 and 5 groups and in the 3 and 6 groups received saline solution, DOX $10mg.kg^{-1}$ and DOX $20mg.kg^{-1}$, respectively. Result: DOX administration (10 and $20mg.kg^{-1}$) caused significant increase in MDA and Apelin, an insignificant increase in NO and a significant decrease in SOD, as compared to the C+P group. Three weeks of the pretreatment endurance exercise resulted in a significant increase of Apelin and SOD, an insignificant increase of NO and an insignificant decrease of MDA, as compared to the C+P group. Furthermore, after three weeks of endurance training and DOX treatment with $10mg.kg^{-1}$ and $20mg.kg^{-1}$, a significant increase in apelin and SOD, and a significant decrease in MDA were detected in comparison to C+DOX10 and/or C+DOX20 groups. There was a significant difference between DOX$10mg.kg^{-1}$ and DOX$20mg.kg^{-1}$ treatments in MDA levels only. Conclusion: Pretreatment exercise may improve myocardial tolerance to DOX-induced cardiotoxicity by inhibition of oxidative stress and up-regulation of antioxidants in heart tissue.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.154-158
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• 2013

Development of dual functional liposome has been studied for cancer theragnostics. Therefore, we focused on ultrasound-sensitive liposomes with doxorubicin (DOX) and gadolinium (Gd) as a theragnostic carrier having a potential for cancer therapy and diagnosis. In this study, Gd(III)-DOTA-modified sonosensitive liposomes (GL) was developed using chemically synthesized Gd(III)-DOTA-DPPE lipid. Sonosensitivity of GL to 1 MHz ultrasound induced 25% of DOX release. The relaxivities ($r_1$) of GL were $7.33-10.34\;mM^{-1}s^{-1}$, which was higher than that of MR-bester$^{(R)}$. Intracellular delivery of DOX from GL by ultrasound irradiation was evaluated according to ultrasound intensity, resulting in increase of uptake of DOX released from ultrasound-triggered GLs compared to GL3 or Doxil$^{(R)}$ without ultrasound. Taken together, this study shows that the paramagnetic and sonosensitive liposomes, GL, is a novel and highly effective delivery system for drug with the potential for broad applications in human disease.