• Toxicological Research
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• 제22권4호
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• pp.315-322
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• 2006

TALP-32 is highly basic protein with a molecular weight of 32 kDa purified from human term placenta. Some basic proteins such as defensins and cecropins are known to induce cell death by increasing membrane permeability and some of them are under development as an anticancer drug especially targeting multi-drug resistant cancers. Therefore, we investigated cytotoxic effect and mechanism of TALP-32 When HeLa cell was incubated with TALP-32, cytotoxicity was increased in time and dose dependent manner. As time goes by, HeLa cells became round and plasma membrane was ruptured. Increase of plasma membrane permeability was determined with LDH release assay. Also in transmission electron microscopy, typical morphology of necrotic cell death, such as cell swelling and intracellular organelle disruption was observed, but DNA fragmentation and caspase activation was not. And necrotic cell death was determined with Annexin V/Pl staining. The cytotoxicity of TALP-32 was minimal and decreased or RBC and Hep3B respectively. These data suggests that TALP-32 induces necrosis on rapidly growing cells but not on slowly growing cells implicating the possibility of its development of anticancer peptide drug.

• Biomolecules & Therapeutics
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• 제20권6호
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• pp.513-519
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• 2012

Although the immense efforts have been made for cancer prevention, early diagnosis, and treatment, cancer morbidity and mortality has not been decreased during last forty years. Especially, lung cancer is top-ranked in cancer-associated human death. Therefore, effective strategy is strongly required for the management of lung cancer. In the present study, we found that novel daphnane diterpenoids, yuanhualine (YL), yuanhuahine (YH) and yuanhuagine (YG) isolated from the flower of Daphne genkwa (Thymelaeaceae), exhibited potent anti-proliferative activities against human lung A549 cells with the $IC_{50}$ values of 7.0, 15.2 and 24.7 nM, respectively. Flow cytometric analysis revealed that the daphnane diterpenoids induced cell-cycle arrest in the G0/G1 as well as G2/M phase in A549 cells. The cell-cycle arrests were well correlated with the expression of checkpoint proteins including the up-regulation of cyclin-dependent kinase inhibitor p21 and p53 and down-regulation of cyclin A, cyclin B1, cyclin E, cyclin dependent kinase 4, cdc2, phosphorylation of Rb and cMyc expression. In the analysis of signal transduction molecules, the daphnane diterpenoids suppressed the activation of Akt, STAT3 and Src in human lung cancer cells. The daphnane diterpenoids also exerted the potent anti-proliferative activity against anticancer-drug resistant cancer cells including gemcitabine-resistant A549, gefitinib-, erlotinib-resistant H292 cells. Synergistic effects in the growth inhibition were also observed when yuanhualine was combined with gemcitabine, gefitinib or erlotinib in A549 cells. Taken together, these findings suggest that the novel daphnane diterpenoids might provide lead candidates for the development of therapeutic agents for human lung cancers.

• 치위생과학회지
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• 제23권3호
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• pp.216-224
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• 2023

Background: Smilax glabra has various pharmacological activities and is widely used as a herbal medicine. Although the incidence of oral cancer is low, the recurrence rate is high, and the 5-year survival rate is poor. It is necessary to search for anticancer drugs that increase the effect of cancer chemotherapy on heterogeneous oral tissues and reduce the side effects on normal cells. This study aimed to investigate the effects and mechanism of ethanol extract of Smilax glabra (EESG) as an anticancer drug for oral cancer. Methods: Smilax glabra root components extracted with 70% ethanol were used to analyze their effects on cancer cells. A 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide assay was performed for cytotoxicity analysis. Flow cytometry was performed to determine the cell cycle phase distribution. To observe apoptotic cells, terminal deoxynucleotidyl transferase dUTP nick end labeling and γH2AX were detected by fluorescence microscope. The protein levels of cleaved PARP and caspase were analyzed using western blotting. The activation of procaspase-3 was confirmed by measuring caspase-3 activity. Results: EESG was no cytotoxic to normal gingival fibroblast but was high in YD10B oral squamous cell carcinoma (OSCC) cells. EESG treatment increased the subdiploid DNA content of YD10B cells by assessing DNA content distribution. Chromatin condensation and DNA strand breaks increased in YD10B cells treated with EESG. EESG-treated YD10B cells had high Annexin V and low propidium iodide levels, confirming that early apoptosis was induced. In addition, increased levels of γH2AX foci, a marker of DNA damage, were observed in the nuclei of EESG-treated YD10B cells. The EESG-treated YD10B cells also exhibited decreased procaspase-3 and procaspase-9 levels, increased PARP cleavage and caspase-3 activity. Conclusion: These results indicate that EESG inhibited cancer cell proliferation by inducing apoptosis in YD10B OSCC cells.

• 생명과학회지
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• 제31권2호
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• pp.199-208
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• 2021

Euonymus porphyreus는 노박덩굴과에 속하는 식물로 동아시아 지역에 널리 분포하며, 식물학상의 특징에 대한 보고는 있으나 항산화능과 항암활성 등에 관한 연구는 아직까지 밝혀진 바가 없다. 이에 본 연구에서는 인체 폐암세포인 A549를 사용하여 E. porphyreus 에탄올 추출물(EEEP)의 항산화 및 항암활성과 그 분자적 기전에 관하여 연구하였다. 먼저 EEEP의 총 폴리페놀 화합물과 플라보노이드 함량을 측정한 결과, 각각 115.42 mg/g, 23.07 mg/g이었다. EEEP의 DPPH radical 소거활성을 측정한 결과, IC50가 11.09 ㎍/ml로 뛰어난 항산화능을 보유한 것을 확인하였다. 또한 EEEP는 농도의존적으로 인체폐암세포주인 A549의 세포 성장을 저해하였으며, 세포 주기 변화를 분석한 결과 A549 세포의 SubG1기 세포비율이 증가하는 것을 확인하였다. Annexin V 염색과 DAPI 염색으로 EEEP 처리에 의해 apoptotic 세포와 apoptotic body가 증가하는 것을 확인하였으며, 이러한 결과는 EEEP에 의해 A549 세포의 apoptosis가 유도되는 것을 시사한다. 또한 관련 단백질들의 발현변화를 분석한 결과, EEEP에 의해 Fas, p53, Bax의 발현이 증가하고 Bcl-2의 발현은 감소하였으며, caspase-8, -9와 caspase-3의 활성화를 통해 PARP가 분해되어 apoptosis가 유도되었음을 확인하였다. 이러한 결과들로부터 EEEP는 내인성 및 외인성 경로를 통한 apoptosis 유도에 의하여 A549 세포의 증식을 억제하는 항암활성을 보유하였음을 확인하였다.

• BMB Reports
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• 제34권3호
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• pp.237-243
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• 2001

Taxol, a natural product extracted from the Taxus brevifolia, is known to have significant anti-tumor activities against many common cancers, including ovarian and breast cancers. Despite the pronounced anti-tumor activity of this compound, its poor solubility in aqueous solutions hampers its clinical applications. We studied the anticancer mechanisms of the water-soluble taxol diethylenetriamine pentaacetate (DTPA) used for radiolabeling, and compared it to that of taxol. In vitro cytotoxicities of taxol and taxol-DTPA conjugate were tested in HT29 human colorectal cancer cells by the MTT method. As the result, the $IC_{50}$ value of the taxol-DTPA conjugate was about three fold higher than that of taxol. When analyzed by an agarose gel electrophoresis, the DNA ladders became evident after the incubation of cells with the taxol-DTPA conjugate for 24 h. We also found morphological changes of the cells undergoing apoptosis with electron microscopy Next, we examined the signal pathway of taxol-DTPA conjugate-induced apoptosis in HT29 cells. The activation of extracellular signal-regulated protein kinase (ERK1/2) occurred at 10, 30, 60 and 120 min after 200 nM taxol-DTPA conjugate treatment. The pretreatment of the MEK inhibitor (PD98059) completely blocked the taxol-DTPA conjugate-induced ERK1/2 activation. The activated ERK1/2 translocated into the nucleus at the same time and phosphorylated its transcriptional factor, c-Jun. These results suggest that the taxol-DTPA conjugate has an apoptotic activity in HT29 cells, and that its proapoptic activity might be related with the signal transduction via ERK1/2 and c-Jun similar to that of taxol.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1219-1225
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• 2014

Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenol molecule from green tea and is known to exhibit antioxidative as well as tumor suppressing activity. In order to examine EGCG tumor invasion and suppressing activity against adult T-cell leukemia (ATL), two HTLV-1 positive leukemia cells (HuT-102 and C91-PL) were treated with non-cytotoxic concentrations of EGCG for 2 and 4 days. Proliferation was significantly inhibited by 100 ${\mu}M$ at 4 days, with low cell lysis or cytotoxicity. HTLV-1 oncoprotein (Tax) expression in HuT-102 and C91-PL cells was inhibited by 25 ${\mu}M$ and 125 ${\mu}M$ respectively. The same concentrations of EGCG inhibited NF-kB nuclearization and stimulation of matrix metalloproteinase-9 (MMP-9) expression in both cell lines. These results indicate that EGCG can inhibit proliferation and reduce the invasive potential of HTLV-1-positive leukemia cells. It apparently exerted its effects by suppressing Tax expression, manifested by inhibiting the activation of NF-kB pathway and induction of MMP-9 transcription in HTLV-1 positive cells.

• 대한본초학회지
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• 제21권4호
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• pp.27-36
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• 2006

Objectives : This study was performed for the investigation of anticancer effects of methanol extract of Rheum Rhizoma (MeOH-RR) on a human liver cancer cell line (HepG2). Methods : To study the cytotoxic effect of MeOH-RR on HepG2 cells, the cell viability was determined by XTT reduction method and trypan blue exclusion assay. The cleavage of poly ADP-ribose polymerase (PARP), a substrate for caspase-3 and a typical sign of apoptosis, and the activation of procaspase-3, -8 and -9 were examined by western blot analysis. Furthermore, MeOH-RR-induced apoptosis was confirmed by DNA fragmentation. The release of cytochrome c from mitochondria to cytosol, the level of Bcl-2 and Bax were examined by western blot analysis. Results : MeOH-RR reduced proliferation of HepG2 cells in a dose-dependent manner at 24 h and 48 h treatment. MeOH-RR induced the activation of caspase-3, -8, and -9 and the cleavage of poly ADP-ribose polymerase (PARP), a substrate for caspase-3. Furthermore, treatment with MeOH-RR resulted in internucleosomal DNA fragmentation, evidenced by the formation of a DNA ladder on agarose gel, a hallmark of cells undergoing apoptosis. MeOH-RR downregulated Bcl-2, upregulated Bax, and increased the release of cytochrome c from the mitochondria into cytosol in a dose-dependent manner. Moreover, MeOH-RP increased caspase-3 activity. Conclusion : There results suggest that MeOH-RR induce apoptosis via mitochondrial pathway and caspase-3-dependent pathway in HepG2 cells. There results suggest that MeOH-RR is potentially useful as a chemotherapeutic agent in human liver cancer.

• Biomolecules & Therapeutics
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• 제24권6호
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• pp.623-629
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• 2016

(1S,2S,3E,7E,11E)-3,7,11,15-cembratetraen-17,2-olide (LS-1), a marine cembrenolide diterpene, has anticancer activity against colon cancer cells such as HT-29, SNU-C5/5-FU (fluorouracil-resistant SNU-C5) and SNU-C5. However, the action mechanism of LS-1 on SNU-C5 human colon cancer cells has not been fully elucidated. In this study, we investigated whether the anticancer effect of LS-1could result from apoptosis via the modulation of $Wnt/{\beta}$-catenin and the TGF-${\beta}$ pathways. When treated with the LS-1, we could observe the apoptotic characteristics such as apoptotic bodies and the increase of sub-G1 hypodiploid cell population, increase of Bax level, decrease of Bcl-2 expression, cleavage of procaspase-3 and cleavage of poly (ADP-ribose) polymerase in SNU-C5 cells. Furthermore, the apoptosis induction of SNU-C5 cells upon LS-1 treatment was also accompanied by the down-regulation of $Wnt/{\beta}$-catenin signaling pathway via the decrease of GSK-$3{\beta}$ phosphorylation followed by the decrease of ${\beta}$-catenin level. In addition, the LS-1 induced the activation of TGF-${\beta}$ signaling pathway with the decrease of carcinoembryonic antigen which leads to decrease of c-Myc, an oncoprotein. These data suggest that the LS-1 could induce the apoptosis via the down-regulation of $Wnt/{\beta}$-catenin pathway and the activation of TGF-${\beta}$ pathway in SNU-C5 human colon cancer cells. The results support that the LS-1 might have potential for the treatment of human colon cancer.

• Journal of Ginseng Research
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• 제39권1호
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• pp.22-28
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• 2015

Background: Sun ginseng (SG), a specific formulation of quality-controlled red ginseng, contains approximately equal amounts of three major ginsenosides (RK1, Rg3, and Rg5), which reportedly has antitumor-promoting activities in animal models. Methods: MTT assay was used to assess whether SG can potentiate the anticancer activity of epirubicin or paclitaxel in human cervical adenocarcinoma HeLa cells, human colon cancer SW111C cells, and SW480 cells; apoptosis status was analyzed by annexin V-FITC and PI and analyzed by flow cytometry; and apoptosis pathway was studied by analysis of caspase-3, -8, and -9 activation, mitochondrial accumulation of Bax and Bak, and cytochrome c release. Results: SG remarkably enhances cancer cell death induced by epirubicin or paclitaxel in human cervical adenocarcinoma HeLa cells, human colon cancer SW111C cells, and SW480 cells. Results of the mechanism study highlighted the cooperation between SG and epirubicin or paclitaxel in activating caspase-3 and -9 but not caspase-8. Moreover, SG significantly increased the mitochondrial accumulation of both Bax and Bak triggered by epirubicin or paclitaxel as well as the subsequent release of cytochrome c in the targeted cells. Conclusion: SG significantly potentiated the anticancer activities of epirubicin and paclitaxel in a synergistic manner. These effects were associated with the increased mitochondrial accumulation of both Bax and Bak that led to an enhanced cytochrome c release, caspase-9/-3 activation, and apoptosis. Treating cancer cells by combining epirubicin and paclitaxel with SG may prove to be a novel strategy for enhancing the efficacy of the two drug types.

• Biomolecules & Therapeutics
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• 제31권1호
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• pp.73-81
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• 2023

Sirtuins (SIRTs) belong to the nicotinamide adenine dinucleotide (NAD+)-dependent class III histone deacetylase family. They are key regulators of cellular and physiological processes, such as cell survival, senescence, differentiation, DNA damage and stress response, cellular metabolism, and aging. SIRTs also influence carcinogenesis, making them potential targets for anticancer therapeutic strategies. In this study, we investigated the anticancer properties and underlying molecular mechanisms of a novel SIRT1 inhibitor, MHY2251, in human colorectal cancer (CRC) cells. MHY2251 reduced the viability of various human CRC cell lines, especially those with wild-type TP53. MHY2251 inhibited SIRT1 activity and SIRT1/2 protein expression, while promoting p53 acetylation, which is a target of SIRT1 in HCT116 cells. MHY2251 treatment triggered apoptosis in HCT116 cells. It increased the percentage of late apoptotic cells and the sub-G1 fraction (as detected by flow cytometric analysis) and induced DNA fragmentation. In addition, MHY2251 upregulated the expression of FasL and Fas, altered the ratio of Bax/Bcl-2, downregulated the levels of pro-caspase-8, -9, and -3 proteins, and induced subsequent poly(ADP-ribose) polymerase cleavage. The induction of apoptosis by MHY2251 was related to the activation of the caspase cascade, which was significantly attenuated by pre-treatment with Z-VAD-FMK, a pan-caspase inhibitor. Furthermore, MHY2251 stimulated the phosphorylation of c-Jun N-terminal kinase (JNK), and MHY2251-triggered apoptosis was blocked by pre-treatment with SP600125, a JNK inhibitor. This finding indicated the specific involvement of JNK in MHY2251-induced apoptosis. MHY2251 shows considerable potential as a therapeutic agent for targeting human CRC via the inhibition of SIRT1 and activation of JNK/p53 pathway.