• Title/Summary/Keyword: Intrinsic pathway

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Current understanding of cancer-intrinsic PD-L1: regulation of expression and its protumoral activity

  • Yadollahi, Pedram;Jeon, You-Kyoung;Ng, Wooi Loon;Choi, Inhak
    • BMB Reports
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    • v.54 no.1
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    • pp.12-20
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    • 2021
  • In the last decade, we have witnessed an unprecedented clinical success in cancer immunotherapies targeting the programmed cell-death ligand 1 (PD-L1) and programmed cell-death 1 (PD-1) pathway. Besides the fact that PD-L1 plays a key role in immune regulation in tumor microenvironment, recently a plethora of reports has suggested a new perspective of non-immunological functions of PD-L1 in the regulation of cancer intrinsic activities including mesenchymal transition, glucose and lipid metabolism, stemness, and autophagy. Here we review the current understanding on the regulation of expression and intrinsic protumoral activity of cancer-intrinsic PD-L1.

Induction of Intrinsic and Extrinsic Apoptosis Pathways in the Human Leukemic MOLT-4 Cell Line by Terpinen-4-ol

  • Khaw-On, Patompong;Banjerdpongchai, Ratana
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.7
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    • pp.3073-3076
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    • 2012
  • Terpinen-4-ol is a terpene found in the rhizome of Plai (Zingiber montanum (Koenig) Link ex Dietr.). In this study apoptogenic activity and mechanisms of cell death induced by terpinen-4-ol were investigated in the human leukemic MOLT-4 cell line. Terpinen-4-ol exhibited cytotoxicity in MOLT-4 cells, with characteristic morphological features of apoptosis by Wright's staining. The mode of cell death was confirmed to be apoptosis by flow cytometric analysis after staining with annexin V-FITC and propidium iodide. A sub-G1 peak in DNA histograms of cell cycle assays was observed. Terpinen-4-ol induced-MOLT-4 cell apoptosis mediated through an intrinsic pathway involving the loss of mitochondrial transmembrane potential (MTP) and release of cytochrome c into the cytosol. In addition, terpinen-4-ol also induced apoptosis via an extrinsic pathway by caspase-8 activation resulting in the cleavage of cytosolic Bid. Truncated-Bid (tBid) translocated to mitochondria and activated the mitochondrial pathway in conjunction with down-regulation of Bcl-2 protein expression. Caspase-3 activity also increased. In conclusion, terpinen-4-ol can induce human leukemic MOLT-4 cell apoptosis via both intrinsic and extrinsic pathways.

Induction of Apoptosis with Moringa oleifera Fruits in HCT116 Human Colon Cancer Cells Via Intrinsic Pathway

  • Guon, Tae-Eun;Chung, Ha Sook
    • Natural Product Sciences
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    • v.23 no.4
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    • pp.227-234
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    • 2017
  • Moringa oleifera Lam (M. oleifera, Moringaceae) is a tree of the Moringaceae family that can reach a height of between 5 and 10 m. The current paper presents cytotoxic effect of M. oleifera fruits and its flavonoids 1 and 2. The viability of HCT116 human colon cancer cells were 38.5% reduced by $150{\mu}g/mL$ of ethanolic extracts in a concentration-dependent manner; in addition, we observed the apoptotic features of cell shrinkage and decreased cell size. Bcl-2 family proteins were regulated as determined by Western blotting analysis, suggesting that M. oleifera fruits and their flavonoids 1 and 2 induced apoptosis through an intrinsic pathway. Based on our findings, 70% ethanolic extracts of M. oleifera fruits and flavonoids 1 and 2 might be useful as cytotoxic agents in colorectal cancer therapy.

Peroxisome Proliferator-Activated Receptor-Gamma Agonist 4-O-Methylhonokiol Induces Apoptosis by Triggering the Intrinsic Apoptosis Pathway and Inhibiting the PI3K/Akt Survival Pathway in SiHa Human Cervical Cancer Cells

  • Hyun, Seungyeon;Kim, Man Sub;Song, Yong Seok;Bak, Yesol;Ham, Sun Young;Lee, Dong Hun;Hong, Jintae;Yoon, Do Young
    • Journal of Microbiology and Biotechnology
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    • v.25 no.3
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    • pp.334-342
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    • 2015
  • 4-O-Methylhonokiol (MH), a bioactive compound derived from Magnolia officinalis, is known to exhibit antitumor effects in various cancer cells. However, the precise mechanism of its anticancer activity in cervical cancer cells has not yet been studied. In this study, we demonstrated that MH induces apoptosis in SiHa cervical cancer cells by enhancing peroxisome proliferator-activated receptor-gamma (PPARγ) activation, followed by inhibition of the PI3K/Akt pathway and intrinsic pathway induction. MH upregulated PPARγ and PTEN expression levels while it decreased p-Akt in the MH-induced apoptotic process, thereby supporting the fact that MH is a PPARγ activator. Additionally, MH decreased the expression of Bcl-2 and Bcl-XL, inducing the intrinsic pathway in MH-treated SiHa cells. Furthermore, MH treatment led to the activation of caspase-3/caspase-9 and proteolytic cleavage of polyADP ribose polymerase. The expression levels of Fas (CD95) and E6/E7 oncogenes were not altered by MH treatment. Taken together, MH activates PPARγ/PTEN expression and induces apoptosis via suppression of the PI3K/Akt pathway and mitochondria-dependent pathways in SiHa cells. These findings suggest that MH has potential for development as a therapeutic agent for human cervical cancer.

Investigation of Biological Activities of Enzymatic Hydrolysate of Spirulina (스피루리나 효소가수분해물의 생리활성 탐색)

  • Son, Min-Hee;Park, Keun-Hyoung;Choi, A-Reum;Yoo, Gui-Jae;In, Man-Jin;Kim, Dong-Ho;Chae, Hee-Jeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.2
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    • pp.136-141
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    • 2009
  • Biological activities of enzymatic hydrolysate of spirulina (EHS) were investigated. EHS showed no significant effects on the growth-stimulating activity for lactic-acid bacteria and antioxidant activity. EHS showed slight in vitro growth-inhibitory effects (15% at 1.42 mg/L) on a human cervical cancer cell line (HeLa). In addition, the anticoagulant activities of EHS were measured based on three different pathways: common, intrinsic and extrinsic pathways. As an indication of anticoagulant activity on common pathway, thrombin time (TT) of EHS (100 mg/L) was measured as 155.6 sec. Activated partial thromboplastin time (aPTT) for intrinsic pathway of EHS (1,000 mg/L) was measured as 95.8 sec. Prothrombin time (PT) based on extrinsic pathway of EHS (1,000 mg/L) was measured as 10.6 sec. These data showed that EHS have influences on anticoagulant factors of common pathway and intrinsic pathway. Consequently it was found that EHS could be used as a functional food for blood circulation.

Angelica polymorpha Maxim Induces Apoptosis of Human SH-SY5Y Neuroblastoma Cells by Regulating an Intrinsic Caspase Pathway

  • Rahman, Md. Ataur;Bishayee, Kausik;Huh, Sung-Oh
    • Molecules and Cells
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    • v.39 no.2
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    • pp.119-128
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    • 2016
  • Angelica polymorpha Maxim root extract (APRE) is a popular herbal medicine used for treating stomachache, abdominal pain, stomach ulcers, and rheumatism; however the effect of APRE on cancer cells has not yet been explored. Here, we examined APRE cytotoxicity seen on target neuroblastoma cells (NB) using cell viability assays, DAPI visualization of fragmented DNA, and Western blotting analysis of candidate signaling pathways involved in proliferation and apoptosis. We demonstrated that APRE reduced cell viability in NB to a greater extent than in fibroblast cells. In addition, we found that APRE could inhibit the three classes of MAPK proteins and could also down-regulate the PI3K/AKT/GSK-$3{\beta}$ activity all being relevant for proliferation and survival. APRE could also up-regulate Bax expression and down-regulate Bcl-2 and Mcl-1. With APRE treatment, depolarization of mitochondria membrane potential and activation of caspase-3 was demonstrated in the SH-SY5Y cells. We could not found increased activity of death receptor and caspase-8 as markers of the extrinsic apoptosis pathway for the APRE treated cells. In presence of a caspase-3 siRNA and a pan-caspase inhibitor, APRE could not reduce the viability of NB cells to a significant degree. So we predicted that with APRE, the intrinsic pathway was solely responsible for inducing apoptosis as we also showed that the non-caspase autophagy pathway or ER stress-ROS mediated pathways were not involved. These findings demonstrate that an intrinsic mitochondria-mediated apoptosis pathway mediates the apoptotic effects of APRE on SH-SY5Y cells, and that APRE shows promise as a novel agent for neuroblastoma therapy.

Screening of Anticoagulant Activities in Extracts from Edible Herbs (허브 추출물의 항응고 활성 검색)

  • 신동훈;이종임;이현순;전우진;유광원;홍범식;조홍연;양한철
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.2
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    • pp.335-341
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    • 2000
  • In order to search for blood anticoagulant substance from herbal extracts, we extracted with cold water (Fr. I), methanol (Fr. II) and hot water (Fr. III) from 93 commercially available herbs. The anticoagulant activity of herbal extracts was examined through the intrinsic pathway by activated partial thromboplastin time (APTT), the extriansic pathway by prothrombin time (PT) and the common pathway by thrombin time (TT). Onion, garlic, clove, fenugreek, mugwort, thyme and sage had on anticoagulant activity with intrinsic pathway and mint, italian seasoning, rosemary, turmeric, tarragon and wasabie had on anticoagulant activity with common pathway. Nobody had on anticogulant activity with extrinsic pathway. Among commerical herbs tested, clove cultivated in holland was selected because it showed the most potent anticoagulant activity among the samples investigated.

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Biological Pathway Extension Using Microarray Gene Expression Data

  • Chung, Tae-Su;Kim, Ji-Hun;Kim, Kee-Won;Kim, Ju-Han
    • Genomics & Informatics
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    • v.6 no.4
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    • pp.202-209
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    • 2008
  • Biological pathways are known as collections of knowledge of certain biological processes. Although knowledge about a pathway is quite significant to further analysis, it covers only tiny portion of genes that exists. In this paper, we suggest a model to extend each individual pathway using a microarray expression data based on the known knowledge about the pathway. We take the Rosetta compendium dataset to extend pathways of Saccharomyces cerevisiae obtained from KEGG (Kyoto Encyclopedia of genes and genomes) database. Before applying our model, we verify the underlying assumption that microarray data reflect the interactive knowledge from pathway, and we evaluate our scoring system by introducing performance function. In the last step, we validate proposed candidates with the help of another type of biological information. We introduced a pathway extending model using its intrinsic structure and microarray expression data. The model provides the suitable candidate genes for each single biological pathway to extend it.

H9 Induces Apoptosis via the Intrinsic Pathway in Non-Small-Cell Lung Cancer A549 Cells

  • Kwon, Sae-Bom;Kim, Min-Je;Sun Young, Ham;Park, Ga Wan;Choi, Kang-Duk;Jung, Seung Hyun;Do-Young, Yoon
    • Journal of Microbiology and Biotechnology
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    • v.25 no.3
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    • pp.343-352
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    • 2015
  • H9 is an ethanol extract prepared from nine traditional/medicinal herbs. This study was focused on the anticancer effect of H9 in non-small-cell lung cancer cells. The effects of H9 on cell viability, apoptosis, mitochondrial membrane potential (MMP; ${\Delta}\psi_{m}$), and apoptosisrelated protein expression were investigated in A549 human lung cancer cells. In this study, H9-induced apoptosis was confirmed by propidium iodide staining, expression levels of mRNA were determined by reverse transcriptase polymerase chain reaction, protein expression levels were checked by western blot analysis, and MMP (${\Delta}\psi_{m}$) was measured by JC-1 staining. Our results indicated that H9 decreased the viability of A549 cells and induced cell morphological changes in a dose-dependent manner. H9 also altered expression levels of molecules involved in the intrinsic signaling pathway. H9 inhibited Bcl-xL expression, whereas Bax expression was enhanced and cytochrome C was released. Furthermore, H9 treatment led to the activation of caspase-3/caspase-9 and proteolytic cleavage of poly(ADP-ribose) polymerase; the MMP was collapsed by H9. However, the expression levels of extrinsic pathway molecules such as Fas/FasL, TRAIL/TRAIL-R, DR5, and Fas-associated death receptor were downregulated by H9. These results indicated that H9 inhibited proliferation and induced apoptosis by activating intrinsic pathways but not extrinsic pathways in human lung cancer cells. Our results suggest that H9 can be used as an alternative remedy for human non-small-cell lung cancer.

Induction of the Intrinsic Apoptotic Pathway by 3-Deazaadenosine Is Mediated by BAX Activation in HL-60 Cells

  • Lee, Sun-Young;Ko, Kyoung-Won;Kang, Won-Kyung;Choe, Yun-Jeong;Kim, Yoon-Hyoung;Kim, In-Kyung;Kim, Jin;Kim, Ho-Shik
    • The Korean Journal of Physiology and Pharmacology
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    • v.14 no.6
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    • pp.407-412
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    • 2010
  • 3-Deazaadenosine (DZA), a potent inhibitor of S-adenosylhomocysteine hydrolase, was previously proposed to induce intrinsic apoptosis in human leukemic cells. In the present study, we analyzed the mechanism underlying the DZA-induced intrinsic apoptotic pathway. DZA activated typical caspase-dependent apoptosis in HL-60 cells, as demonstrated by an accumulation of hypo-diploidic cells, the processing of multiple procaspases and an inhibitory effect of z-VAD-Fmk on this cell death. During DZA-induced apoptosis, cytochrome c (cyt c) was released into the cytosol. This was neither prevented by z-VAD-Fmk and nor was it associated with the dissipation of mitochondrial membrane potential (${\Delta}{\Psi}_m$). Prior to the release of cyt c, BAX was translocated from the cytosol to mitochondria and underwent oligomerization. Finally, the overexpression of BCL-XL protected HL-60 cells from apoptosis by blocking both the cyt c release and BAX oligomerization. Collectively, these findings suggest that DZA may activate intrinsic apoptosis by stimulating BAX activation and thereby the release of cyt c.