• 생명과학회지
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• 제15권5호
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• pp.726-733
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• 2005

Histone deacetylase (HDAC) 억제제가 새로운 항암치료제 후보물질로서 유용성이 높은 것으로 평가되지만, 아직까지 인체폐암세포에 관한 연구는 상대적으로 미미한 실정이다. 따라서 본 연구에서는 폐암세포에 미치는 HDAC 억제제의 항암작용 기전을 조사하기 위하여 A549 인체폐암세포주를 대상으로 암세포의 증식에 미치는 대표적인 HDAC 억제제인 tichostatin A (TSA)에 의한 영향을 세포주기 조절관련인자 중심으로 조사하였다. TSA의 처리에 의하여 A549 폐암세포의 증식은 처리 농도 의존적으로 억제되었으며, 심한 형태적 변형을 동반하였다. 저농도 처리군에서는 TSA 농도가 증가할수록 세포주기 G1기의 빈도가 증가하였으나, 고농도 처리군에서는 G2/M기에 속하는 세포의 빈도가 증가되었다. 또한 apoptosis 유발의 간접적인 지표가 되는 sub-G1기에 속하는 세포의 빈도 역시 TSA 처리 농도 의존적으로 매우 증가되었다. 이러한 TSA의 A549 폐암세포 증식억제 효과는 cyclins 및 CdkS의 발현 억제, 종양억제유전자인 p53 및 Cdks 억제제인 p21과 p27의 발현 증가와도 연관성이 있었다. TSA의 항암 기전을 규명하기 위해서는 더 많은 연구가 부가적으로 필요하겠지만, 본 연구의 결과들에 의하면 TSA는 강력한 인체폐암세포의 증식 억제 및 항암작용이 있음을 시사하여 준다고 할 수 있다.

• Applied Biological Chemistry
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• 제50권3호
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• pp.228-232
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• 2007

본 연구는 만형자(Vitex rotundifolia)의 세포독성을 확인하기 위한 목적으로 methanol, ethanol, acetone으로 추출한 뒤, 인간 유래의 대장암 세포주인 HT-29에 처리하여 MTT reduction assay를 이용하여 실험을 하였다. 그 결과, 모든 만형자 추출물에서 농도 의존적으로 성장 저해 효과가 나타났으며, 그 중에서도 acetone 추출물을 50 ${\mu}g/ml$ 농도로 처리 시 18%로 가장 높은 항암 효과를 보였다. 또한 각 용매별 추출물을 50 ${\mu}g/ml$를 처리하여 HT-29 세포주의 성장을 관찰한 결과, acetone 추출물은 대조구에 비하여 암세포의 수축 등 형태변화가 두드러지게 나타났으며, Hoechst 33342 staining을 통하여 apoptotic body가 형성된 것을 확인 하였다. 그리고 가장 활성이 좋은 acetone 추출물을 용매 분획하여 얻은 분획물 중, n-hexane 분획물에서 농도 의존적으로 세포독성을 나타냄을 알 수 있었다. 또한 만형자의 n-hexane 분획물은 다른 대장암 세포주 SW620에 대해서도 50 ${\mu}g/ml$ 농도에서 대조군에 비하여 7배 정도의 높은 세포독성을 나타내고 있음을 MTT reduction assay와 LDH release assay를 통하여 확인 할 수 있었다.

• 생명과학회지
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• 제24권11호
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• pp.1244-1251
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• 2014

길경(桔梗, Platycodon grandiflorum)은 도라지의 뿌리로 항염증, 항알러지, 면역 반응, 당뇨, 고지혈증 및 항암 효과 등을 가지고 있는 것으로 알려져 있다. 하지만 길경의 항암 효과에 대한 연구는 미미하며, 길경이 유발하는 autophagy에 대한 연구는 되어 있지 않다. 본 연구에서는 HCT-116 대장암 세포주에서 길경 추출물이 autophagy와 apoptosis를 유발하면서 세포 성장을 억제하는지의 여부를 조사하였다. 길경 추출물은 농도 및 시간의존적으로 세포의 증식을 억제하였으며, 길경 추출물에 의해 나타나는 apoptosis는 caspase의 활성이 부분적으로 관여되어 있음을 알 수 있었다. 또한, 길경 추출물의 처리는 autophagy에 의해 나타나는 공포를 형성하면서 autophagy와 관련되어 있는 여러 단백질의 발현 조절 및 LC3 단백질의 축적이 동반되었다. 길경 추출물에 의해 유도되는 autophay와 apoptosis의 관계를 알아보기 위해서 3-MA나 bafilomycin A1을 처리하여 autophagy를 억제하였을 때 apoptosis가 유의적으로 증가됨을 알 수 있었다. 흥미롭게도 bafilomycin A1을 처리한 결과에서 길경 추출물에 의한 세포성장 억제가 뚜렷하게 회복되는 양상을 보였다. 따라서 본 연구의 결과는 HCT-116 세포에서 길경 추출물에 의해 유도된 autophagy는 세포 보호적인 작용이 아닌 autophagic cell death이며, 길경 추출물이 대장암 세포주에서 암세포의 사멸을 유도하는 효과적인 대안이 될 수 있음을 알 수 있었다.

• 대한한의학방제학회지
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• 제25권3호
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• pp.391-412
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• 2017

Objective : In this study, we searched the experimental research about combined treatment of anticancer drug and herbal medicine for killing or inhibiting proliferation of Cancer cells searched in OASIS and KISS. This study aimed to analyze the experimental research paper about anticancer drug combined treatment with herbal medicine. Methods : We collected the research paper including killing or inhibiting proliferation of Cancer cells in OASIS and KISS using keyword anticancer drug with herbal medicine, tumor suppressor with herbal medicine, inhibition of Cancer with herbal medicine and combined treatment with herbal medicine. Assorting by cancer cells, we analyzed experimental results cancer cell viability, anticancer drug dosage, tumor weight and survival rate. Also, we checked the effects of herbal medicine on cancer and additive effect reducing side effect of anticancer drug. Results : Total 45 studies were selected. 38 studies reported combined treatment of anticancer drug and herbal medicine was more effective than only anticancer drug. The death of cancer cells was synergistically induced by the cotreatment of anticancer drug and herb extracts. The studies suggest that the cotreatment of anticancer drug and herb extracts could reduce side effect of anticancer drug. In addition, some studies reported cotreatment mechanism like apoptotic death signal processes. In combined treatment of anticancer drug and herb extracts, The expression of Fas/Fas L, Bax, Bcl2, Caspase-3 etc.. was markedly increased in cancer cells. Conclusions : Our results suggest that anticancer drug combined treatment with herbal medicine could be efficient for killing or inhibiting proliferation of cancer cells. However, this paper had some limitation as follows: First, collected studies have been published only for korean journal. Second, results of research and effects of combined treatment are not collected objectively. To solve these problems, more objective and balanced studies should be performed.

• 한국식품영양과학회지
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• 제37권5호
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• pp.555-560
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• 2008

사람 두경부 편평세포암종 HEp2 세포를 이용하여 아미노산 수송계 L 억제제인 BCH의 암세포 성장억제에 미치는 효과와 세포성장 억제기전을 밝히기 위해 HEp2 세포에서 uptake 실험, MTT 분석, DNA fragmentation 분석 및 immunoblotting 등을 시행하여 다음과 같은 결과를 얻었다. 아미노산 수송계 L 억제제인 BCH는 L-leucine uptake를 농도 의존적으로 억제하였으며, 그 $IC_{50}$은$ 51.2{\pm}3.8{\mu}M$로 산출되었다. BCH는 HEp2 세포의 성장을 시간과 농도에 의존적으로 억제하였다. BCH를 처리한 실험군에서 DNA fragmentation 현상은 볼 수 없었다. BCH를 처리한 실험군에서 procaspase-3과 procaspase-7의 proteolytic cleavage 현상은 볼 수 없었다. 본 연구의 결과로서 사람 두경부 편평세포 암종 HEp2 세포에서 아미노산 수송계 L 억제제 BCH는 LAT1 활성을 억제하여 세포성장에 필수적인 L-leucine 등 중성아미노산의 세포 내 고갈을 유도함으로써 HEp2 세포의 성장억제를 유도할 가능성이 있는 것으로 사료된다.

• 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.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3581-3586
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• 2014

Aim: To investigate the effects of tetramethypyrazine (TMP) on proliferation and apoptosis of the human gastric carcinoma cell line 7901 and its possible mechanism of action. Methods: The viability of TMP-treated 7901 cells was measured with a 3-(4, 5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT) and cell apoptosis was analyzed by flow cytometry. The distribution of cells in different phases of cell cycle after exposure of TMPs was analyzed with flow cytometry. To investigate the molecular mechanisms of TMP-mediated apoptosis, the expression of NF-${\kappa}Bp65$, cyclinD1 and p16 in SGC-7901 cells was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. Results: TMP inhibited the proliferation of human gastric carcinoma cell line 7901 in dose and time dependent manners. Cell growth was suppressed by TMP at different concentrations (0.25, 0.5, 1.0, 2.0 mg/ml), the inhibition rate is 0.46%, 4.36%, 14.8%, 76.1% (48h) and 15.5%, 18.5%, 41.2%, 89.8% (72h) respectively. When the concentration of TMPs was 2.0mg/ml, G1-phase arrest in the SGC-7901 cells was significant based on the data for cell cycle distribution. RT-PCR demonstrated that NF-${\kappa}Bp65$ and cyclin D1 mRNA expression was significantly down-regulated in 7901 cells treated with 2.0 mg/ml TMP for 72h (p<0.05), while the p16 mRNA level was up-regulated (p<0.05). The protein expression of NF-${\kappa}Bp65$ and cyclin D1 decreased gradually with the increase in TMP concentration, compared with control cells (p<0.05), while expression of protein p16 was up-regulated (p<0.01). Conclusion: TMP exhibits significant anti-proliferative and pro-apoptotic effects on the human gastric carcinoma cell line SGC-7901. NF-${\kappa}Bp65$, cyclinD1 and p16 may also play important roles in the regulation mechanisms.

• Asian Pacific Journal of Cancer Prevention
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• 제14권9호
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• pp.4983-4988
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• 2013

Objectives: To establish a taxol-resistant cell line of human ovarian carcinoma (A2780/Taxol) and investigate its biological features. Methods: The drug-resistant cell line (A2780/Taxol) was established by continuous stepwise selection with increasing concentrations of Taxol. Cell morphology was assessed by microscopy and growth curves were generated with in vitro and in vivo tumor xenograft models. With rhodamine123 (Rh123) assays, cell cycle distribution and the apoptotic rate were analyzed by flow cytometry (FCM). Drug resistance-related and signal associated proteins, including P-gp, MRPs, caveolin-1, PKC-${\alpha}$, Akt, ERK1/2, were detected by Western blotting. Results: A2780/Taxol cells were established with stable resistance to taxol. The drug resistance index (RI) was 430.7. Cross-resistance to other drugs was also shown, but there was no significant change to radioresistance. Compared with parental cells, A2780/Taxol cells were significantly heteromorphous, with a significant delay in population doubling time and reduced uptake of Rh123 (p<0.01). In vivo, tumor take by A2780 cells was 80%, and tumor volume increased gradually. In contrast, with A2780/Taxol cells in xenograft models there was no tumor development. FCM analysis revealed that A2780/Taxol cells had a higher percentage of G0/G1 and lower S phase, but no changes of G2 phase and the apoptosis rate. Expression of P-gp, MRP1, MRP2, BCRP, LRP, caveolin-1, PKC-${\alpha}$, Phospho-ERK1/2 and Phospho-JNK protein was significantly up-regulated, while Akt and p38 MARK protein expression was not changed in A2780/Taxol cells. Conclusion: The A2780/Taxol cell line is an ideal model to investigate the mechanism of muti-drug resistance related to overexpression of drug-resistance associated proteins and activation of the PKC-${\alpha}/ERK$ (JNK) signaling pathway.

• 생명과학회지
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• 제24권7호
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• pp.769-776
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• 2014

Anisomycin은 Streptomyces griseolus에 의하여 생성되는 항생제의 일종으로 flagecidin으로도 알려져 있으며, ribosomal 28S subunit에 결합함으로서 단백질의 생성을 억제하는 것으로 알려져 있다. TRAIL은 ligand로서의 death receptor와의 결합을 통하여 세포의 apoptosis를 유발하는 것으로 알려져 있으나, 많은 암세포에서는 이미 TRAIL에 대한 저항성을 획득하여 TRAIL 유도 apoptosis를 회피하는 능력을 가지고 있다. 본 연구에서는 TRAIL 저항성 Hep3B 간암세포를 대상으로 anisomycin이 TRAIL 매개 apoptosis를 촉진 시킬 수 있는지의 여부를 조사하였다. 본 연구의 결과에 의하면, 단독 처리 조건에서 Hep3B 세포의 증식에 유의적인 영향을 미치는 않았던 anisomycin과 TRAIL의 동시 처리는 anisomycin 처리 농도 의존적으로 세포의 증식을 시켰으며, 이는 caspase 활성화를 통한 apoptosis 유발 증가와 연관성이 있음을 확인하였다. 특히 siRNA를 이용한 Hep3B 세포의 인위적인 Bid 발현의 차단은 anisomycin과 TRAIL 동시 처리군에 비하여 apoptosis 유발능이 더욱 증대시켜 TRAIL 연관 Bid의 truncation을 통한 미토콘드리아 의존적 apoptosis 유발 과정을 anisomycin이 효과적으로 촉진시켰음을 보여주었다. 따라서 본 연구의 결과는 anisomycin과 TRAIL의 동시 처리는 TRAIL 저항성 암세포의 사멸을 촉진시킬 수 있는 효과적인 방법임을 의미한다.

• Animal cells and systems
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• 제6권2호
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• pp.171-180
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• 2002

Nitric oxide has high affinity for iron, and thus it can cause intracellular iron loss. We tested the idea that intracellular iron can be the primary target of NO toxicity by comparing the signaling mechanisms involved in cell death caused by iron depletion and that caused by NO. Treatment of HL-60 cells with a NO donor, S-nitroso-N-acetyl-DL-penicillamine (SNAP), decreased the intracellular iron level rapidly as that observed with the iron chelator deferoxamine (DFO). Iron chelators such as DFO and mimosine could induce death of human leukemic HL-60 cells by a mechanism requiring activation of p38 kinase, c-Jun N-terminal kinase, caspase-3 and caspase-8. DFO and SNAP also caused release of cytochrome c from mitochondria. Inhibition of p38 kinase by a selective inhibitor, SB203580, abolished the NO and DFO-induced cell death, release of cytochrome c, and activation of caspase-3 and caspase-8, thus indicating that p38 kinase lies upstream in the cell death processes. In a parallel situation, the cells that are sensitive to NO showed similar sensitivity to DFO. Moreover, simultaneous addition of ferric citrate, an iron-containing compound, inhibited the SNAP and DFO-induced activation of caspases and also blocked the NO-mediated cell cycle arrest at $G_1$ phase. Collectively, our data implicate that the NO-induced cell death of tumor cells including HL-60 cells is mediated by depletion of iron and further suggest that activation of p38 kinase lies upstream of cytochrome c release and caspase activation involved in this apoptotic process.