• Archives of Pharmacal Research
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• v.21 no.3
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• pp.266-272
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• 1998

The present study investigated the antitumor activity of the aqueous-alcoholic extracts from unripe cotton balls of Gossypium indicum. An Exposure of murine B16 melanoma and L1210 lymphoma cells to the extracts resulted in their severe deaths in time- and concentration-dependent manners. Of the extracts, hydrophilic fractions were most efficacious for the antitumor activity and found to contain certain amounts of catechin and its derivatives. The hydrophilic extract fraction C36B2-8 had approximately 10 times more cytotoxic effects on B12 and L1210 cells than on isolated murine thymocytes. High concentrations (>150 $\mu$g/ml) of C 36B3-8 mainly induced necrotic cell death. At low concentrations (<100 $\mu$g/ml), however, C 36B3-8 induced not only necrosis but also apoptosis of the two tumor cell lines, which was proved by the TUNEL staining and DNA fragmentation techniques. The data indicate that certain ingredients of the cotton ball extract of G. indicum have an antitumor activity.

• Journal of Life Science
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• v.23 no.9
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• pp.1118-1125
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• 2013

Naringenin, a naturally occurring citrus flavonone, is a potentially valuable candidate for cancer chemotherapy. However, the cellular and molecular mechanisms responsible for its anticancer activity are largely unknown. In the present study, we attempted to elucidate the mechanisms responsible for naringenin-induced apoptosis in human leukemic U937 cells. We found that naringenin markedly inhibited the growth of U937 cells by decreasing cell proliferation and inducing apoptosis, which was associated with the activation of caspases. A pan-caspase inhibitor, z-VAD-fmk, significantly inhibited naringenin-induced U937 cell apoptosis, indicating that caspases are key regulators of apoptosis in response to naringenin in U937 cells. Although the levels of antiapoptotic Bcl-2 and proapoptotic Bax proteins remained unchanged in naringenin-treated U937 cells, Bcl-2 overexpression attenuated naringenin-induced apoptosis. Furthermore, combined treatment with naringenin and HA14-1, a small-molecule Bcl-2 inhibitor, effectively increased the apoptosis through enhancement of XIAP down-regulation, Bid cleavage, and caspase activation, suggesting that the synergistic effect was at least partially mediated through the death receptor-mediated apoptosis pathway.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8337-8343
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• 2014

Paclitaxel is one of the best anticancer agents that has been isolated from plants, but its major disadvantage is its dose-limiting toxicity. In this study, we obtained evidence that the active mutant IPP5 ($8-60hIPP5^m$), the latest member of the inhibitory molecules for protein phosphatase 1, sensitizes human cervix carcinoma cells HeLa more efficiently to the therapeutic effects of paclitaxel. The combination of $8-60hIPP5^m$ with paclitaxel augmented anticancer effects as compared to paclitaxel alone as evidenced by reduced DNA synthesis and increased cytotoxicity in HeLa cells. Furthermore, our results revealed that $8-60hIPP5^m$ enhances paclitaxel-induced G2/M arrest and apoptosis, and augments paclitaxel-induced activation of caspases and release of cytochrome C. Evaluation of signaling pathways indicated that this synergism was in part related to downregulation of NF-${\kappa}B$ activation and serine/threonine kinase Akt pathways. We noted that $8-60hIPP5^m$ downregulated the paclitaxel-induced NF-${\kappa}B$ activation, $I{\kappa}B{\alpha}$ degradation, PI3-K activity and phosphorylation of the serine/threonine kinase Akt, a survival signal which in many instances is regulated by NF-${\kappa}B$. Together, our observations indicate that paclitaxel in combination with $8-60hIPP5^m$ may provide a therapeutic advantage for the treatment of human cervical carcinoma.

• Journal of Life Science
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• v.18 no.1
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• pp.120-128
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• 2008

The death ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)/ Apo1L is a cytokine that activates apoptosis through cell surface death receptors. TRAIL has sparked growing interest in oncology due to its reported ability to selectively trigger cancer cell death. Euphorbiae humifusae Wind has been used in traditional Oriental medicine as a folk remedy used for the treatment of cancer. However, the mechanism responsible for the anticancer effects of E. humifusae not clearly understood. Here, we show that treatment with subtoxic doses of water extract of E. humifusae (WEEH) in combination with TRAIL induces apoptosis in TRAIL-resistant human gastric carcinoma AGS cells. Combined treatment with WEEH and TRAIL induced chromatin condensation and sub-G1 phase DNA content. These indicators of apoptosis were correlated with the induction of caspase activity that resulted in the cleavage of poly (ADP-ribose) polymerase. Combined treatment also triggered the loss of mitochondrial membrane potential. Furthermore, co-treatment with WEEH and TRAIL down-regulated the protein levels of the anti-apoptotic proteins such as Bcl-2, Bcl-xL, XIAP and cIAP-1. Although more study will be needed to examine the detailed mechanisms, this combined treatment may offer an attractive strategy for safely treating gastric adenocarcinomas and the results provide important new insights into the possible molecular mechanisms of the anticancer activity of E. humifusae.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.2
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• pp.169-178
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• 2013

Objectives : Many cancers acquired resistance to chemotherapy, thus limiting its anticancer efficacy. It is known that Glutathione (GSH) is related to the development of drug resistance. The expression of GSH synthesizing glutamylcysteine ligase (GCL) was controlled by nuclear factor-E2-related factor(Nrf2). Previous studies showed that pharmacological depletion of GSH results in ROS increase, apoptotic response, and sensitization to oxidizing stimuli. In the current study, we examined Saussurea Lappa (SL) have the inhibitory effect on Nrf2 activity using human lung cancer A549 cells overexpressing Nrf2. Methods : Cell viability of A549 cells on SL treatment was determined by MTT assay. To detect the apeptosis in SL-treated A549 cells, sub-G1 population was measured by flow cytometry analysis (FACS). The level ROS was determined by FACS and fluorescence microscopy. To investigate whether SL have effect the suppression on Nrf2, we performed western blotting analysis. The GSH content was measured since GSH plays an important role in response to oxidative stress and was regulated by Nrf2. Results : A549 cells treated with an SL extract showed a substantial decrease in cell viability, along with a concomitant increase in apoptosis compared to untreated cells. Treatment of the SL extract led to increased Reactive oxygen species (ROS) production and a suppression of Nrf2. In addition, the antioxidant NAC attenuated SL-induced ROS generation, Nrf2 inhibition, and apoptosis. Taken together, these data show that the SL extract induced the production of ROS, and the inhibition of Nrf2, consequently resulting in A549 cell death. Conclusions : These results suggest that SL might be an effective agent to enhance anticancer drug sensitivity via Nrf2 inhibition.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.1
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• pp.73-84
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• 2024

A pulsed electromagnetic field (PEMF) enhances the efficacy of several anticancer drugs. Doxorubicin (DOX) is an anticancer agent used to treat various malignancies, including breast cancer. This study examined whether a PEMF increases the anticancer effect of DOX on MCF-7 human breast cancer cells and elucidated the underlying mechanisms affected by PEMF stimulation in DOX-treated MCF-7 human breast cancer cells. A cotreatment with DOX and a PEMF potentiated the reduction in MCF-7 cell viability compared to the treatment with DOX alone. The PEMF elevated DOX-induced G1 arrest by affecting cyclin-dependent kinase 2 phosphorylation and the expression of G1 arrest-related molecules, including p53, p21, cyclin E2, and polo like kinase 1. In addition, PEMF increased the DOX-induced upregulation of proapoptotic proteins, such as Fas and Bcl-2-associated X, and the downregulation of antiapoptotic proteins, including myeloid leukemia 1 and survivin. PEMF promoted the DOX-induced activation of caspases-8, -9, and -7 and poly (adenosine diphosphate-ribose) polymerase cleavage in MCF-7 cells. In conclusion, PEMF enhances the anticancer activity in DOX-treated MCF-7 breast cancer cells by increasing G1 cell cycle arrest and caspase-dependent apoptosis. These findings highlight the potential use of a PEMF as an adjuvant treatment for DOX-based chemotherapy against breast cancer.

• Journal of Ginseng Research
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• v.41 no.2
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• pp.227-231
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• 2017

Background: Ginsenosides are active components of Panax ginseng that exert various health benefits including kidney protection effect. The medicinal activity of ginsenosides can be enhanced by modulating their stereospecificity by heat processing. Ginsenosides Rk2 and Rh3 represent positional isomers of the double bond at C-20(21) or C-20(22). Methods: The present study investigated the kidney-protective effects of ginsenosides Rk2 and Rh3 against cisplatin, a platinum based anticancer drug, induced apoptotic damage in renal proximal LLC-PK1 cells. Results: As a result, ginsenoside Rh3 shows a stronger protective effect than that shown by Rk2. Cisplatin-induced elevated protein levels of phosphorylated c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), p38, and cleaved caspase-3 decreased after cotreatment with ginsenoside Rh3. The increase in the percentage of apoptotic LLC-PK1 cells induced by cisplatin treatment also significantly reduced after cotreatment with ginsenoside Rh3. Conclusion: These results demonstrate that inhibition of the JNK and ERK mitogen-activated protein kinase signaling cascade plays a critical role in mediating the renoprotective effect of ginsenoside Rh3.

• Journal of Life Science
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• v.25 no.9
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• pp.1051-1058
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• 2015

Citrus mutant fruits were induced by irradiation of citrus budsticks with 120 Gy of cobalt (⁶⁰CO) gamma irradiation. The citrus mutant inhibited the growth and induced apoptosis in various human cancer cells, including A549, HepG2, HCT116, MCF-7, and Hela. The results of a trypan blue exclusion assay showed that citrus mutant fruits exhibited excellent antiproliferation activity in various human cancer cells and low cytotoxicity in normal 16HBE140- and CHANG cells. In addition, the cell death induced by the citrus mutant fruits was associated with an increased population of cells in sub-G1 phase, and it caused DNA fragmentation in human lung adenocarcinoma A549 and hepatocellular carcinoma HepG2 cells. It also up-regulated the amount of cellular nitric oxide (NO^•) produced as a result of nitric oxide synthase (NOS) activation and suppressed the inhibitor of apoptosis protein (IAP) family in A549 and HepG2 cells. These findings indicate that the citrus mutant fruits activates the NO^•-mediated apoptotic pathway in A549 and HepG2 cells. It may merit further investigation as a potential chemotherapeutic and chemopreventive agent for the treatment of various types of cancer cells. The results provide important major new insights into the mechanisms of the anticancer activity of citrus mutant fruits.

• Toxicological Research
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• v.35 no.2
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• pp.167-179
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• 2019

Ovarian cancer is the fifth main cause of pre-senescent death in women. Although chemotherapy is generally an efficient treatment, its side effects and the occurrence of chemotherapeutic resistance have prompted the need for alternative treatments. In this study, ${\alpha}$-mangostin and apigenin were evaluated as possible anticancer alternatives to the chemotherapeutic drug doxorubicin, used herein as a positive control. The ovarian adenocarcinoma cell line SKOV-3 (ATCC No. HTB77) was used as model ovarian cancer cells, whereas the skin fibroblast line CCD-986Sk (ATCC No. CRL-1947) and lung fibroblast line WI-38 (ATCC No. CCL-75) were used as model untransformed cells. Apigenin and doxorubicin inhibited the growth of SKOV-3 cells in a dose- and time-dependent manner. After 72 hr exposure, doxorubicin was mostly toxic to SKOV-3 cells, whereas apigenin was toxic to SKOV-3 cells but not CCD-986Sk and WI-38 cells. ${\alpha}$-Mangostin was more toxic to SKOV-3 cells than to CCD-986Sk cells. A lower cell density, cell shrinkage, and more unattached (floating round) cells were observed in all treated SKOV-3 cells, but the greatest effects were observed with ${\alpha}$-mangostin. With regard to programmed cell death, apigenin caused early apoptosis within 24 hr, whereas ${\alpha}$-mangostin and doxorubicin caused late apoptosis and necrosis after 72 hr of exposure. Caspase-3 activity was significantly increased in ${\alpha}$-mangostin-treated SKOV-3 cells after 12 hr of exposure, whereas only caspase-9 activity was significantly increased in apigenin-treated SKOV-3 cells at 24 hr. Both ${\alpha}$-mangostin and apigenin arrested the cell cycle at the $G_2/M$ phase, but after 24 and 48 hr, respectively. Significant upregulation of BCL2 (apoptosis-associated gene) and COX2 (inflammation-associated gene) transcripts was observed in apigenin- and ${\alpha}$-mangostin-treated SKOV-3 cells, respectively. ${\alpha}$-Mangostin and apigenin are therefore alternative options for SKOV-3 cell inhibition, with apigenin causing rapid early apoptosis related to the intrinsic apoptotic pathway, and ${\alpha}$-mangostin likely being involved with inflammation.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5339-5343
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• 2012

The induction of apoptosis in target cells is a key mechanism for most anti-tumor therapies. Bufalin is a cardiotonic steroid that has the potential to induce differentiation and apoptosis of tumor cells. Research on bufalin has so far mainly involved leukemia, prostate cancer, gastric cancer and liver cancer, and has been confined to in vitro studies. The bufadienolides bufalin and cinobufagin have been shown to induce apoptosis in a wide spectrum of cancer cell. The present article reviews the anticancer effects of bufalin. It induces apoptosis of lung cancer cells via the PI3K/Akt pathway and also suppressed the proliferation of human non-small cell lung cancer A549 cell line in a time and dose dependent manner. Bufalin, bufotalin and gamabufotalin, key bufadienolides, significantly sensitize human breast cancer cells with differing ER-alpha status to apoptosis induction by the TNF-related apoptosis-inducing ligand (TRAIL). In addition, bufadienolides induce prostate cancer cell apoptosis more significantly than that in breast epithelial cell lines. Similar effects have been observed with hepatocellular carcinoma (HCC) but the detailed molecular mechanisms of inducing apoptosis in this case are still unclear. Bufalin exerts profound effects on leukemia therapy in vitro. Results of multiple studies indicate that bufalin has marked anti-tumor activities through its ability to induce apoptosis. Large-scale randomized, double-blind, placebo or positive drug parallel controlled studies are now required to confirm the efficacy and apoptosis-inducing potential of bufalin in various cancers in the cliniucal setting.