• Asian Pacific Journal of Cancer Prevention
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• 제15권10호
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• pp.4353-4358
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• 2014

Background: PI3/AKT and NF-kB signaling pathways are constitutively active in acute myeloid leukemia and cross-talk between the two has been shown in various cancers. However, their role in acute myeloid leukemia has not been completely explored. We therefore used cell penetrating inhibitor peptides to define the contributions of AKT and NF-kB to survival and multi drug resistance (MDR) in HL-60 cells. Materials and Methods: Inhibition of AKT and NF-kB activity by AKT inhibitor peptide and NBD inhibitor peptide, respectively, resulted in decreased expression of mRNA for the MDR1 gene as assessed by real time PCR. In addition, treatment of HL-60 cells with AKT and NBD inhibitor peptides led to inhibition of cell viability and induction of apoptosis in a dose dependent manner as detected by flow cytometer. Results: Finally, co-treatment of HL-60 cells with sub-optimal doses of AKT and NBD inhibitor peptides led to synergistic apoptotic responses in AML cells. Conclusions: These data support a strong biological link between NF-kB and PI3-kinase/AKT pathways in the modulation of antiapoptotic and multi drug resistant effects in AML cells. Synergistic targeting of these pathways using NF-kB and PI3-kinase/AK inhibitor peptides may have a therapeutic potential for AML and possibly other malignancies with constitutive activation of these pathways.

• KSBB Journal
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• 제24권1호
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• pp.80-88
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• 2009

glandular kallikrein에 광범위한 상동성을 가지는 인간 전립성 산성 인산 가수분해 효소는, 전립선암의 대표적인 혈청 biomarkers이다. 수지상세포는 유력한 항원 제시 세포이며, 바이러스, 미생물 병원체 및 종양에 대하여 면역 계통에서 강력한 T 세포 응답을 유도할 수 있다. 따라서, 종양 특이적인 항원으로 감작된 수지상세포를 이용한 면역요법은 anti-tumor 면역 유도를 위한 강력한 방법중의 하나이다. 크레아젠(주)에서 개발된 CTP (세포막 투과성 펩티드) 기술은 세포 내로의 높은 침투 효율성을 가지며 핵산이나 단백질과 같은 생체 고분자 물질을 접합하여 세포내로 수송할 수 있는 기술이다(36). 하지만 활성형의 인간 전립성 산성 인산 가수분해 효소는 세포사멸을 매개할 수 있기 때문에, 본 연구진은 항암 치료용 백신으로의 수지상세포 감작을 위해 비활성형 형태의 다중체 (multimer) 항원을 개발하였다. 본 연구에서, 수지상 세포의 감작과 활성화에 안전하고 효율적인 다중체 형태 (multimeric form)의 세포막 투과성 펩티드가 융합된 인간 전립성 산성 인산 가수분해 효소를 얻기 위한 정제공정을 기법을 개발하였고 젤 여과 크로마토그래피, western blot과 Dynamic Light Scattering을 이용하여 확인하였다. 아울러, 정제된 다중체 형태 (multimeric form)의 세포막 투과성 펩티드가 융합된 인간 전립성 산성 인산 가수분해 효소는 수지상 세포의 감작시 세포질 내로 효과적으로 침투되었다. 결과적으로 세포의 사멸의 부작용이 없이 MHC class I 분자를 통해 수지상세포의 표면으로 효과적으로 제시되었다.

• 생명과학회지
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• 제28권1호
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• pp.37-42
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• 2018

NAG-1 단백질은 TGF-${\beta}$ superfamily 유전자로서 암세포의 apoptosis를 유도하고 항암 활성과 관련이 있는 것으로 알려져 있다. 본 연구에서는 프로폴리스 유래의 파이토케미칼 CAPE (caffeic acid phenethyl ester)에 의한 항암유전자 NAG-1의 발현과 발현조절에 대해 연구하였다. 인간 대장암 세포주 HCT116에서 CAPE의 처리에 의해 농도의존적, 시간의존적으로 NAG-1의 발현이 증가됨을 확인하였다. 게다가, 다른 대장암 세포주인 LOVO 세포주에서도 농도의존적으로 NAG-1의 발현이 증가됨을 확인하였다. p53-null HCT116세포주를 이용한 실험에서 CAPE에 의한 NAG-1의 발현은 전사조절인자인 p53에 의존하지 않음을 증명하였다. 또한, 3가지 종류의 NAG-1 프로모터 construct를 이용한 실험에서, cis-element 후보가 -474와 -1,086사이에 있음을 증명하였다. CAPE에 의해 전사조절인자인 ATF3와 CREB의 발현이 변화되는 지를 확인한 결과, CREB은 전혀 발현이 증가되지 않는 반면 ATF3는 CAPE 처리에 의해 농도의존적으로 발현이 증가함을 확인하였다. 그리고, pCG-ATF3와 pCREB의 cotransfection 실험에서 CREB은 NAG-1의 발현에 영향을 못 미치는 반면, ATF3의 과대발현에 의해 NAG-1의 발현이 증가됨을 확인하였다. 결론적으로, CAPE에 의한 NAG-1의 발현은 주로 전사조절인자인 ATF3를 경유하여 일어남을 시사한다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7825-7829
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• 2014

Objective: To investigate the effect of high expression of XAF1 in vivo or in vitro on lung cancer cell growth and apoptosis. Methods: 1. The A549 human lung cancer cell line was transfected with Ad5/F35 - XAF1, or Ad5/F35 - Null at the same multiplicity of infection (MOI); (hereinafter referred to as transient transfected cell strain); XAF1 gene mRNA and protein expression was detected by reverse transcription polymerase chain reaction (RT-PCR) and Western blotting respectively. 2. Methyl thiazolyl tetrazolium (MTT) and annexin V-FITC/PI double staining were used to detect cell proliferation and apoptosis before and after infection of Ad5/F35 - XAF1 with Western blotting for apoptosis related proteins, caspase 3, caspase - 8 and PARP. 3. After the XAF1 gene was transfected into lung cancer A549 cells by lentiviral vectors, and selected by screening with Blasticidin, reverse transcription polymerase chain reaction (RT-PCR) and Western blotting were applied to detect mRNA and protein expression, to establish a line with a stable high expression of XAF1 (hereinafter referred to as stable expression cell strain). Twenty nude mice were randomly divided into groups A and B, 10 in each group: A549/XAF1 stable expression cell strain was subcutaneously injected in group A, and A549/Ctrl stable cell line stable expression cell strain in group B (control group), to observe transplanted tumor growth in nude mice. Results: The mRNA and protein expression of XAF1 in A549 cells transfected by Ad5/F35 - XAF1 was significantly higher than in the control group. XAF1 mediated by adenovirus vector demonstrated a dose dependent inhibition of lung cancer cell proliferation and induction of apoptosis. This was accompanied by cleavage of caspase -3, -8, -9 and PARP, suggesting activation of intrinsic or extrinsic apoptotic pathways. A cell strain of lung cancer highly expressing XAF1 was established, and this demonstrated delayed tumor growth after transplantation in vivo. Conclusion: Adenovirus mediated XAF1 gene expression could inhibit proliferation and induce apoptosis in lung cancer cells in vitro; highly stable expression of XAF1 could also significantly inhibit the growth of transplanted tumors in nude mouse, with no obvious adverse reactions observed. Therefore, the XAF1 gene could become a new target for lung cancer treatment.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.6039-6046
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• 2015

Aims: To investigate effect of metallic nanoparticles, silver (AgNPs) and gold nanoparticles (AuNPs) as antitumor treatment in vitro against human breast cancer cells (MCF-7) and their associated mechanisms. This could provide new class of engineered nanoparticles with desired physicochemical properties and may present newer approaches for therapeutic modalities to breast cancer in women. Materials and Methods: A human breast cancer cell line (MCF-7) was used as a model of cells. Metallic nanoparticles were characterized using UV-visible spectra and transmission electron microscopy (TEM). Cytotoxic effects of metallic nanoparticles on MCF-7 cells were followed by colorimetric SRB cell viability assays, microscopy, and cellular uptake. Nature of cell death was further investigated by DNA analysis and flow cytometry. Results: Treatment of MCF-7 with different concentrations of 5-10nm diameter of AgNPs inhibited cell viability in a dose-dependent manner, with IC50 value of $6.28{\mu}M$, whereas treatment of MCF-7 with different concentrations of 13-15nm diameter of AuNPs inhibited cell viability in a dose-dependent manner, with IC50 value of $14.48{\mu}M$. Treatment of cells with a IC50 concentration of AgNPs generated progressive accumulation of cells in the S phase of the cell cycle and prevented entry into the M phase. The treatment of cells with IC50 concentrations of AuNPs similarly generated progressive accumulation of cells in sub-G1 and S phase, and inhibited the entrance of cells into the M phase of the cell cycle. DNA fragmentation, as demonstrated by electrophoresis, indicated induction of apoptosis. Conclusions: Our engineered silver nanoparticles effectively inhibit the proliferation of human breast carcinoma cell line MCF-7 in vitro at high concentration ($1000{\mu}M$) through apoptotic mechanisms, and may be a beneficial agent against human carcinoma but further detailed study is still needed.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3731-3736
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• 2014

Phytic acid (PA) has been reported to have positive nutritional benefits and prevent cancer formation. This study investigated the anticancer activity of rice bran PA against hepatocellular carcinoma (HepG2) cells. Cytotoxicty of PA (0.5 to 4mM) was examined by MTT and LDH assays after 24 and 48h treatment. Apoptotic activity was evaluated by expression analysis of apoptosis-regulatory genes [i.e. p53, Bcl-2, Bax, Caspase-3 and -9] by reverse transcriptase-PCR and DNA fragmentation assay. The results showed antioxidant activity of PA in Fe3+ reducing power assay ($p{\leq}0.03$). PA inhibited the growth of HepG2 cells in a concentration dependent manner ($p{\leq}0.04$). After 48h treatment, cell viability was recorded 84.7, 74.4, 65.6, 49.6, 36.0 and 23.8% in MTT assay and 92.6, 77.0%, 66.8%, 51.2, 40.3 and 32.3% in LDH assay at concentrations of 1, 1.5, 2.0, 2.5, 3.0, and 3.5mM, respectively. Hence, treatment of PA for 24h, recorded viability of cells 93.5, 88.6, 55.5, 34.6 and 24.4% in MTT assay and 94.2, 86.1%, 59.7%, 42.3 and 31.6%, in LDH assay at concentrations of 1, 2.2, 3.0, 3.6 and 4.0mM, respectively. PA treated HepG2 cells showed up-regulation of p53, Bax, Caspase-3 and -9, and down-regulation of Bcl-2 gene ($p{\leq}0.01$). At the $IC_{50}$ (2.49mM) of PA, the p53, Bax, Caspase-3 and-9 genes were up-regulated by 6.03, 7.37, 19.7 and 14.5 fold respectively. Also, the fragmented genomic DNA in PA treated cells provided evidence of apoptosis. Our study confirmed the biological activity of PA and demonstrated growth inhibition and induction of apoptosis in HepG2 cells with modulation of the expression of apoptosis-regulatory genes.

• 대한핵의학회지
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• 제34권2호
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• pp.144-153
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• 2000

목적: 피부세포인 A431세포주에서 방사선 조사에 의한 세포고사가 방사선량과 방사선 조사 후 경과시간에 따라서 어떻게 변하는지를 밝혀보고, 방사선에 의해 유도된 수선유전자의 발현을 방사선량별, 조사 후 경과시간별로 분석하여 세포고사와 어떤 관계가 있는지 알아보고자 하였다. 대상 및 방법: 한국 세포주은행으로부터 분양받은 피부상피암 세포의 일종인 A431을 Cs-137 세포조사기를 이용하여 5 Gy, 25 Gy씩 조사하고 4, 12, 48시간이 지난 다음 세포를 모아 유세포계측법을 이용하여 고사세포를 계수하였다. 또한 이 세포들을 Northern blot analysis, Western blot analysis를 시행하여 방사선량별, 경과시간별로 유전자의 변화를 분석하였다. 각 실험군간의 통계적 유의성은 SPSS 통계프로그램을 사용하여 MANOVA test에 의해 검정하였으며, p값 0.05 미만을 유의한 수준으로 판정하였다. 결과: 유세포 계측기로 측정한 고사세포의 비율은 방사선 조사 후 12시간째에 가장 유의하게 증가하였다 (p<0.01). DNA수선유전자의 발현은 5 Gy 조사 후 p53, p21, hRAD 유전자가 12시간째에 증가하였고, 25 Gy 조사 후에는 hRAD50과 p21이 12시간에 증가하였으며, p53과 GADD45는 12시간까지 별 변화가 없었으나 이후 증가하여 48시간에 가장 높은 발현을 보였다. 결론: 피부상피암세포에서 방사선에 의해 유도되는 세포고사는 방사선 조사 후 12시간에 가장 현저해지는 것을 알 수 있었으며, 이 세포고사에 DNA수선 유전자가 밀접한 관련이 있을 것으로 보이는데, 특히 최근에 발견된 hRAD50 유전자도 세포고사와 밀접한 관련이 있을 것으로 사료되었다.

• 대한한의학방제학회지
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• 제25권1호
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• pp.51-68
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• 2017

Objectives : Oxidative stress due to excessive accumulation of reactive oxygen species (ROS) is one of the risk factors for the development of several chronic diseases, including neurodegenerative diseases. Methods : In the present study, we investigated the protective effects of cheongnoemyeongsin-hwan (CNMSH) against oxidative stress‑induced cellular damage and elucidated the underlying mechanisms in neuronal-derived SH-SY5Y cells. Results : Our results revealed that treatment with CNMSH prior to hydrogen peroxide (H2O2) exposure significantly increased the SH-SY5Y cell viability, indicating that the exposure of the SH-SY5Y cells to CNMSH conferred a protective effect against oxidative stress. CNMSH also effectively attenuated H2O2‑induced comet tail formation, and decreased the phosphorylation levels of the histone ${\gamma}H2AX$, as well as the number of apoptotic bodies and Annexin V‑positive cells. In addition, CNMSH exhibited scavenging activity against intracellular ROS generation and restored the mitochondria membrane potential (MMP) loss that were induced by H2O2, suggesting that CNMSH prevents H2O2‑induced DNA damage and cell apoptosis. Moreover, H2O2 enhanced the cleavage of caspase-3 and degradation of poly (ADP-ribose)-polymerase, a typical substrate protein of activated caspase-3, as well as DNA fragmentation; however, these events were almost totally reversed by pretreatment with CNMSH. Furthermore, CNMSH increased the levels of heme oxygenase-1 (HO-1), which is a potent antioxidant enzyme, associated with the induction of nuclear factor-erythroid 2-related factor 2 (Nrf2). According to our data, CNMSH is able to protect SH-SY5Y cells from H2O2-induced apoptosis throughout blocking cellular damage related to oxidative stress through a mechanism that would affect ROS elimination and activating Nrf2/HO-1 signaling pathway. Conclusions : Therefore, we believed that CNMSH may potentially serve as an agent for the treatment and prevention of neurodegenerative diseases caused by oxidative stress.

• Asian Pacific Journal of Cancer Prevention
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• 제15권24호
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• pp.10659-10663
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• 2015

Background: Rapamycin is an effective anti-angiogenic drug. However, the mode of its action remains unclear. Therefore, in this study, we aimed to elucidate the antitumor mechanism of rapamycin, hypothetically via apoptotic promotion, using MCF-7 breast cancer cells. Materials and Methods: MCF-7 cells were plated at a density of $1{\times}10^5$ cells/well in 6-well plates. After 24h, cells were treated with a series of concentrations of rapamycin while only adding DMEM medium with PEG for the control regiment and grown at $37^{\circ}C$, 5% $CO_2$ and 95% air for 72h. Trypan blue was used to determine the cell viability and proliferation. Untreated and rapamycin-treated MCF-7 cells were also examined for morphological changes with an inverted-phase contrast microscope. Alteration in cell morphology was ascertained, along with a stage in the cell cycle and proliferation. In addition, cytotoxicity testing was performed using normal mouse breast mammary pads. Results: Our results clearly showed that rapamycin exhibited inhibitory activity on MCF-7 cell lines. The $IC_{50}$ value of rapamycin on the MCF-7 cells was determined as $0.4{\mu}g/ml$ (p<0.05). Direct observation by inverted microscopy demonstrated that the MCF-7 cells treated with rapamycin showed characteristic features of apoptosis including cell shrinkage, vascularization and autophagy. Cells underwent early apoptosis up to 24% after 72h. Analysis of the cell cycle showed an increase in the G0G1 phase cell population and a corresponding decrease in the S and G2M phase populations, from 81.5% to 91.3% and 17.3% to 7.9%, respectively. Conclusions: This study demonstrated that rapamycin may potentially act as an anti-cancer agent via the inhibition of growth with some morphological changes of the MCF-7 cancer cells, arrest cell cycle progression at G0/G1 phase and induction of apoptosis in late stage of apoptosis. Further studies are needed to further characterize the mode of action of rapamycin as an anti-cancer agent.

• Toxicological Research
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• 제32권1호
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• pp.73-80
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• 2016

Chronic exposure to cadmium (Cd) is known to adversely affect renal function. Our previous studies indicated that Cd induces p53-dependent apoptosis by inhibiting gene expression of the ubiquitin-conjugating enzyme (Ube) 2d family in both human and rat proximal tubular cells. In this study, the effects of Cd on protein expression of p53 and apoptotic signals in the kidney and liver of mice exposed to Cd for 12 months were examined, as well as the effects of Cd on p53 protein levels and gene expression of the Ube2d family in various cell lines. Results showed that in the kidney of mice exposed to 300 ppm Cd for 12 months, there was overaccumulation of p53 proteins in addition to the induction of apoptosis, which was triggered specifically in the proximal tubules. Interestingly, the site of apoptosis was the same as that of p53 accumulation in the proximal tubules. In the liver of mice chronically exposed to Cd, gene expression of the Ube2d family tended to be slightly decreased, together with slight apoptosis without the accumulation of p53 protein. In rat small intestine epithelial (IEC-6) cells, Cd decreased not only the p53 protein level but also gene expression of Ube2d1, Ube2d2 and Ube2d4. In human brain microvascular endothelial cells (HBMECs), Cd did not suppress gene expression of the Ube2d family, but increased the p53 protein level. In human brain astrocytes (HBASTs), Cd only increased gene expression of UBE2D3. These results suggest that Cd-induced apoptosis through p53 protein is associated with renal toxicity but not hepatic toxicity, and the modification of p53 protein by Cd may vary depending on cell type.