• Title/Summary/Keyword: apoptotic pathways

Search Result 264, Processing Time 0.024 seconds

In Vitro Apoptosis Triggering in the BT-474 Human Breast Cancer Cell Line by Lyophilised Camel's Milk

  • Hasson, Sidgi S.A.A;Al-Busaidi, Juma Zaid;Al-Qarni, Zahra A.M.;Rajapakse, S.;Al-Bahlani, Shadia;Idris, Mohamed Ahmed;Sallam, Talal A.
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.15
    • /
    • pp.6651-6661
    • /
    • 2015
  • Breast cancer is a global health concern and is a major cause of death among women. In Oman, it is the most common cancer in women, with an incidence rate of 15.6 per 100,000 Omani females. Various anticancer remedies have been discovered from natural products in the past and the search is continuing for additional examples. Cytotoxic natural compounds may have a major role in cancer therapy either in potentiating the effect of chemotherapy or reducing its harmful effects. Recently, a few studies have reported advantages of using crude camel milk in treating some forms of cancer. However, no adequate data are available on the lyophilised camel's milk responsibility for triggering apoptosis and oxidative stress associated with human breast cancer. The present study aimed to address the role of the lyophilised camel's milk in inducing proliferation repression of BT-474 and HEp-2 cells compared with the non-cancer HCC1937 BL cell line. Lyophilized camel's milk fundamentally repressed BT-474 cells growth and proliferation through the initiation of either the intrinsic and extrinsic apoptotic pathways as indicated by both caspase-3 mRNA and its action level, and induction of death receptors in BT-474 but not the HEp-2 cell line. In addition, lyophilised camel's milk enhanced the expression of oxidative stress markers, heme-oxygenase-1 and reactive oxygen species production in BT-474 cells. Increase in caspase-3 mRNA levels by the lyophilised camel's milk was completely prevented by the actinomycin D, a transcriptional inhibitor. This suggests that lyophilized camel's milk increased newly synthesized RNA. Interestingly,it significantly (p<0.003) repressed the growth of HEp-2 cells and BT-474 cells after treatment for 72 hours while 24 hours treatment repressed BT-474 cells alone. This finding suggests that the lyophilised camel's milk might instigate apoptosis through initiation of an alternative apoptotic pathway.

Anti-oxidative and Anti-cancer Activities of Treculia africana Extract in Human Colon Adenocarcinoma HT29 Cells (대장암세포주 HT29에서의 Treculia africana 추출물의 항산화 및 항암 활성 분석)

  • Oh, You Na;Jin, Soojung;Park, Hyun-jin;Kim, Byung Woo;Kwon, Hyun Ju
    • Journal of Life Science
    • /
    • v.25 no.5
    • /
    • pp.515-522
    • /
    • 2015
  • Treculia africana Decne, a breadfruit species, is native to many parts of West and Tropical Africa. The breadfruit belongs to the family Moraceae and is one of the four members of the genera Treculia. The crude extract of T. africana has been used in folk medicine as an anti-inflammatory agent for various ailments, such as whooping cough. In this study, we evaluated the anti-oxidative and anti-cancer activities of the methanol extract of T. africana Decne (META) and the molecular mechanisms of its anti-cancer effects in human colon carcinoma HT29 cells. The META exhibited anti-oxidative activity through a DPPH radical scavenging capacity and inhibited cell growth in a dose-dependent manner in HT29 cells. META treatment induced apoptosis of HT29 cells, showing an increase in the percentage of both SubG1 cells and Annexin V-positive cells and the formation of apoptotic bodies in a dose-dependent manner. META-mediated apoptosis was associated with the up-regulation of the death receptor FAS and Bax and a decrease in the Bcl-2 expression. META-treated HT29 cells also showed the release of cytochrome c from the mitochondria into the cytosol, activation of caspase-3, caspase-8, and caspase-9, and proteolytic cleavage of poly ADP-ribose polymerase (PARP). These findings suggest META may exert an anti-cancer effect in HT29 cells by inducing apoptosis through both intrinsic and extrinsic pathways.

Protective Effects of Samul-tang on Oxidative Stress induced Death of H9c2 Cardioblast Cells (배양심근세포의 산화적 손상에 대한 사물탕의 방어효과)

  • Cho Kwon-Il;Jung Seung-Won;Jang Jae-Ho;Lee Dae-Yong;Park Sae-Wook;Lee In;Sin Sun-Ho;Moon Byung-Soon
    • The Journal of Korean Medicine
    • /
    • v.26 no.1 s.61
    • /
    • pp.174-186
    • /
    • 2005
  • Objectives : The water extract of Samul-tang (SMT) has traditionally been used for treatment of ischemic heart and brain damage in oriental medicine. However, little is known about the mechanism by which the water extract of SMT rescues cells from these damages. Methods: This study was designed to investigate the protective mechanisms of SMT on oxidative stress-induced toxicity in H9c2 cardiomyoblast cells. Treatment with $H_2O_2$ markedly induced death of H9c2 cardiomyoblast cells in a dose-dependent manner. Results: The characteristics of H20z-induced death of H9c2 showed apparent apoptotic features such as DNA fragmentation and morphological change. However, SMT significantly reduced both H202-induced cell death and morphological change. The decrease of Bc-2 expression by High were inhibited by SMT. In addition, the increase of Bax expression was also inhibited by SMT. The cotreatment of SMT and $H_2O_2$ in H9c2 cells also induced the phosphorylation of ERK in a time-dependent manner. Moreover, PD98059, a specific inhibitor of ERK1/2 attenuated the protective effects of SMT on $H_2O_2-induced$ toxicity in H9c2 cardiomyoblast cells. These results suggest that both ERK1/2 signaling pathways play important roles in the protective effects of SMT on $H_2O_2-induced$ apoptotic death of H9c2 cells. Also, the expression profile of proteins in $H_2O_2$ cardiomyoblast cells were screened by using two-dimensional (2-D) gel electrophoresis. Among 300 spots resolved in 2-D gels, the comparison of control versus apoptosis cells revealed that signal intensity of 17 spots increased and 11 spots decreased. Conclusions: Taken together, this study suggests that the protectiw effects of the water extract of SMT against oxidative damages may be mediated by the modulation of Bc1-2 and Bax expression via the regulation of the ERK signaling pathway.

  • PDF

Mechanism underlying NO-induced apoptosis in human gingival fibroblasts

  • Hwang, In-Nam;Jeong, Yeon-Jin;Jung, Ji-Yeon;Lee, Jin-Ha;Kim, Kang-Moon;Kim, Won-Jae
    • International Journal of Oral Biology
    • /
    • v.34 no.1
    • /
    • pp.7-14
    • /
    • 2009
  • Nitric oxide (NO) acts as an intracellular messenger at the physiological level but can be cytotoxic at high concentrations. The cells within periodontal tissues, such as gingival and periodontal fibroblasts, contain nitric oxide syntheses and produce high concentrations of NO when exposed to bacterial lipopolysaccharides and cytokines. However, the cellular mechanisms underlying NO-induced cytotoxicity in periodontal tissues are unclear at present. In our current study, we examined the NO-induced cytotoxic mechanisms in human gingival fibroblasts (HGF). Cell viability and the levels of reactive oxygen species (ROS) were determined using a MTT assay and a fluorescent spectrometer, respectively. The morphological changes in the cells were examined by Diff-Quick staining. Expression of the Bcl-2 family and Fas was determined by RT-PCR or western blotting. The activity of caspase-3, -8 and -9 was assessed using a spectrophotometer. Sodium nitroprusside (SNP), a NO donor, decreased the cell viability of the HGF cells in a dose- and time-dependent manner. SNP enhanced the production of ROS, which was ameliorated by NAC, a free radical scavenger. ODQ, a soluble guanylate cyclase inhibitor, did not block the SNP-induced decrease in cell viability. SNP also caused apoptotic morphological changes, including cell shrinkage, chromatin condensation, and DNA fragmentation. The expression of Bax, a member of the proapoptotic Bcl-2 family, was upregulated in the SNP-treated HGF cells, whereas the expression of Bcl-2, a member of the anti-apoptotic Bcl-2 family, was downregulated. SNP augmented the release of cytochrome c from the mitochondria into the cytosol and enhanced the activity of caspase-8, -9, and -3. SNP also upregulated Fas, a component of the death receptor assembly. These results suggest that NO induces apoptosis in human gingival fibroblast via ROS and the Bcl-2 family through both mitochondrial- and death receptor-mediated pathways. Our data also indicate that the cyclic GMP pathway is not involved in NO-induced apoptosis.

Apoptotic Effects of Curcumin and EGCG via Akt-p53 Signaling Pathway in HCT116 Colon Cancer Cells (HCT116 대장암 세포에서 Akt-p53 신호경로를 통한 커큐민과 EGCG의 apoptosis 효과)

  • Park, Song-Yi;Lee, Sol-Hwa;Park, Ock-Jin;Kim, Young-Min
    • Journal of Life Science
    • /
    • v.21 no.1
    • /
    • pp.89-95
    • /
    • 2011
  • p53 is tumor suppressor gene that regulates apoptosis such as caspase-dependent and p21-mediated signaling pathways. PI3K/Akt is known to be over-activated in cancer cells. Akt activates many survival-related signals such as mTOR and COX-2. Inactivation of Akt would result in non-inhibition of p53 as well as induced apoptosis. In this study, we showed that curcumin and EGCG activate p53 via inhibition of the Akt signaling pathway. Treatments using curcumin and EGCG in different concentrations for 24 hr and 48 hr inhibited proliferation of HCT116 colon cancer cells and increased apoptotic cell death. Also, our data showed that curcumin and EGCG increased the p53 expression and decreased the p-Akt. Treatment of LY294002 (Akt inhibitor) resulted in decreased cell proliferation of cancer cells, while LY294002 treated with curcumin or EGCG showed a greater decrease of cell proliferation. In addition, inhibition of Akt induced p53 activation in HCT116 colon cancer cells. These results suggest that curcumin and EGCG induce apoptosis by inhibiting Akt and increase p53 in HCT116 colon cancer cells.

The Functional Role of Lysosomes as Drug Resistance in Cancer (항암제 내성에 대한 라이소좀의 역할)

  • Woo, Seon Min;Kwon, Taeg Kyu
    • Journal of Life Science
    • /
    • v.31 no.5
    • /
    • pp.527-535
    • /
    • 2021
  • Lysosomes are organelles surrounded by membranes that contain acid hydrolases; they degrade proteins, macromolecules, and lipids. According to nutrient conditions, lysosomes act as signaling hubs that regulate intracellular signaling pathways and are involved in the homeostasis of cells. Therefore, the lysosomal dysfunction occurs in various diseases, such as lysosomal storage disease, neurodegenerative diseases, and cancers. Multiple forms of stress can increase lysosomal membrane permeabilization (LMP), resulting in the induction of lysosome-mediated cell death through the release of lysosomal enzymes, including cathepsin, into the cytosol. Here we review the molecular mechanisms of LMP-mediated cell death and the enhancement of sensitivity to anticancer drugs. Induction of partial LMP increases apoptosis by releasing some cathepsins, whereas massive LMP and rupture induce non-apoptotic cell death through release of many cathepsins and generation of ROS and iron. Cancer cells have many drug-accumulating lysosomes that are more resistant to lysosome-sequestered drugs, suggesting a model of drug-induced lysosome-mediated chemoresistance. Lysosomal sequestration of hydrophobic weak base anticancer drugs can have a significant impact on their subcellular distribution. Lysosome membrane damage by LMP can overcome resistance to anticancer drugs by freeing captured hydrophobic weak base drugs from lysosomes. Therefore, LMP inducers or lysosomotropic agents can regulate lysosomal integrity and are novel strategies for cancer therapy.

IKKγ Facilitates the Activation of NF-κB by Hsp90 (Hsp90에 의한 NF-κB의 활성화를 촉진하는 IKKγ의 역할)

  • Lee, Jeong Ah;Kim, Dong Wan
    • Journal of Life Science
    • /
    • v.32 no.3
    • /
    • pp.241-248
    • /
    • 2022
  • NF-κB acts as a critical transcription factor in inflammation and innate immunity, and it is also closely involved in cell survival and tumorigenesis via induction of anti-apoptotic genes. In these processes, NF-κB cooperates with multiple other signaling molecules and pathways, and although many studies have demonstrated that Hsp90 regulates NF-κB activity, the exact mechanism is unclear. In this study, we investigated the relationship between Hsp90 and IKKγ in the regulation of NF-κB using expression plasmids of IKK complex components. Wild-type and deletion mutants of IKKγ were expressed together with Hsp90, and the combined regulatory effect of Hsp90 and IKKγ on NF-κB activation was assayed. The results show that Hsp90 activates NF-κB by promoting the phosphorylation and degradation of IκBα and that activation of NF-κB by NIK and LPS was increased by Hsp90. IKKγ elevated the effect of Hsp90 on NF-κB activation by increasing phosphorylation and degradation of IκBα. The positive regulation on NF-κB by Hsp90 and IKKγ was also proved in analysis with IKKβ-EE, the constitutively active form of IKKβ. In experiments with the deletion mutants of IKKγ, the N-terminal IKKβ binding domain, C-terminal leucine zipper, and zinc finger domains of IKKγ were found not necessary for the positive regulation of NF-κB activity. Additionally, the expression of pro-inflammatory cytokines was synergistically elevated by Hsp90 and IKKγ. These results indicate that inhibiting the interaction between Hsp90 and IKKγ is a possible strategic method for controlling NF-κB and related diseases.

Neuroprotective effects of hesperetin on H2O2-induced damage in neuroblastoma SH-SY5Y cells

  • Ha-Rin Moon;Jung-Mi Yun
    • Nutrition Research and Practice
    • /
    • v.17 no.5
    • /
    • pp.899-916
    • /
    • 2023
  • BACKGROUND/OBJECTIVES: Oxidative stress is a fundamental neurodegenerative disease trigger that damages and decimates nerve cells. Neurodegenerative diseases are chronic central nervous system disorders that progress and result from neuronal degradation and loss. Recent studies have extensively focused on neurodegenerative disease treatment and prevention using dietary compounds. Heseperetin is an aglycone hesperidin form with various physiological activities, such as anti-inflammation, antioxidant, and antitumor. However, few studies have considered hesperetin's neuroprotective effects and mechanisms; thus, our study investigated this in hydrogen peroxide (H2O2)-treated SH-SY5Y cells. MATERIALS/METHODS: SH-SY5Y cells were treated with H2O2 (400 µM) in hesperetin absence or presence (10-40 µM) for 24 h. Three-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assays detected cell viability, and 4',6-diamidino-2-phenylindole staining allowed us to observe nuclear morphology changes such as chromatin condensation and apoptotic nuclei. Reactive oxygen species (ROS) detection assays measured intracellular ROS production; Griess reaction assays assessed nitric oxide (NO) production. Western blotting and quantitative polymerase chain reactions quantified corresponding mRNA and proteins. RESULTS: Subsequent experiments utilized various non-toxic hesperetin concentrations, establishing that hesperetin notably decreased intracellular ROS and NO production in H2O2-treated SH-SY5Y cells (P < 0.05). Furthermore, hesperetin inhibited H2O2-induced inflammation-related gene expression, including interluekin-6, tumor necrosis factor-α, and nuclear factor kappa B (NF-κB) p65 activation. In addition, hesperetin inhibited NF-κB translocation into H2O2-treated SH-SY5Y cell nuclei and suppressed mitogen-activated protein kinase protein expression, an essential apoptotic cell death regulator. Various apoptosis hallmarks, including shrinkage and nuclear condensation in H2O2-treated cells, were suppressed dose-dependently. Additionally, hesperetin treatment down-regulated Bax/Bcl-2 expression ratios and activated AMP-activated protein kinase-mammalian target of rapamycin autophagy pathways. CONCLUSION: These results substantiate that hesperetin activates autophagy and inhibits apoptosis and inflammation. Hesperetin is a potentially potent dietary agent that reduces neurodegenerative disease onset, progression, and prevention.

Induction of Tumor Suppressor Gene p53-dependent Apoptosis by Sanguinarine in HCT116 Human Colorectal Cancer Cells (결장암세포에서 sanguinarine에 의한 종양억제 유전자 p53 의존적 apoptosis 유도)

  • Choi, Yung Hyun
    • Journal of Life Science
    • /
    • v.31 no.4
    • /
    • pp.400-409
    • /
    • 2021
  • Sanguinarine, a natural benzophenanthridine alkaloid, has been considered a potential therapeutic target for the treatment of cancer because it can induce apoptosis in human cancer cells; however, the underlying mechanisms of action still remain unclear. Tumor suppressor p53 deletion or mutation is an important reason for the resistance of colorectal cancer cells to anticancer agents. Therefore, in the present study, the role of p53 during apoptosis induced by sanguinarine was investigated in p53wild type (WT, p53+/+) and p53null (p53+/+) HCT116 colon carcinoma cells. Sanguinarine significantly caused greater reductions in cell viability in HCT116 (p53+/+) cells than in HCT116 (p53-/-) cells. Consistently, sanguinarine promoted more DNA damage and apoptosis in HCT116 (p53+/+) cells than in HCT116 (p53-/-) cells while increasing the expression of p53 and cyclin-dependent kinase inhibitor p21WAF1/CIP1. Sanguinarine increased the activity of caspase-8 and caspase-9, which are involved in the initiation of extrinsic and intrinsic apoptosis pathways, respectively, and it activated caspase-3, a typical effect caspase, in HCT116 (p53+/+) cells. Sanguinarine also increased the generation of reactive oxygen species (ROS), and the Bax/Bcl-2 ratio, while destroying the integrity of mitochondria in HCT116 (p53+/+) cells, but not in HCT116 (p53-/-) cells. Overall, the results indicate that sanguinarine induced p53-dependent apoptosis through ROS-mediated activation of extrinsic and intrinsic apoptotic pathways in HCT116 colorectal cancer cells.

Growth Inhibitory and Pro-Apoptotic Effects of Hirsuteine in Chronic Myeloid Leukemia Cells through Targeting Sphingosine Kinase 1

  • Gao, Shan;Guo, Tingting;Luo, Shuyu;Zhang, Yan;Ren, Zehao;Lang, Xiaona;Hu, Gaoyong;Zuo, Duo;Jia, Wenqing;Kong, Dexin;Yu, Haiyang;Qiu, Yuling
    • Biomolecules & Therapeutics
    • /
    • v.30 no.6
    • /
    • pp.553-561
    • /
    • 2022
  • Chronic myeloid leukemia (CML) is a slowly progressing hematopoietic cell disorder. Sphingosine kinase 1 (SPHK1) plays established roles in tumor initiation, progression, and chemotherapy resistance in a wide range of cancers, including leukemia. However, small-molecule inhibitors targeting SPHK1 in CML still need to be developed. This study revealed the role of SPHK1 in CML and investigated the potential anti-leukemic activity of hirsuteine (HST), an indole alkaloid obtained from the oriental plant Uncaria rhynchophylla, in CML cells. These results suggest that SPHK1 is highly expressed in CML cells and that overexpression of SPHK1 represents poor clinical outcomes in CML patients. HST exposure led to G2/M phase arrest, cellular apoptosis, and downregulation of Cyclin B1 and CDC2 and cleavage of Caspase 3 and PARP in CML cells. HST shifted sphingolipid rheostat from sphingosine 1-phosphate (S1P) towards the ceramide coupled with a marked inhibition of SPHK1. Mechanistically, HST significantly blocked SPHK1/S1P/S1PR1 and BCR-ABL/PI3K/Akt pathways. In addition, HST can be docked with residues of SPHK1 and shifts the SPHK1 melting curve, indicating the potential protein-ligand interactions between SPHK1 and HST in both CML cells. SPHK1 overexpression impaired apoptosis and proliferation of CML cells induced by HST alone. These results suggest that HST, which may serve as a novel and specific SPHK1 inhibitor, exerts anti-leukemic activity by inhibiting the SPHK1/S1P/S1PR1 and BCR-ABL/PI3K/Akt pathways in CML cells, thus conferring HST as a promising anti-leukemic drug for CML therapy in the future.