Zeaxanthin Induces Apoptosis in Human Uveal Melanoma Cells through Bcl-2 Family Proteins and Intrinsic Apoptosis Pathway

The cytotoxic effects of zeaxanthin on two human uveal melanoma cell lines (SP6.5 and C918) and related signaling pathways were studied and compared to effects on normal ocular cells (uveal melanocytes, retinal pigment epithelial cells, and scleral fibroblasts). MTT assay revealed that zeaxanthin reduced the cell viability of melanoma cells in a dose-dependent manner (10, 30, and 100 μM), with IC50at 40.8 and 28.7 μM in SP6.5 and C918 cell lines, respectively. Zeaxanthin did not affect the viability of normal ocular cells even at the highest levels tested (300 μM), suggesting that zeaxanthin has a selectively cytotoxic effect on melanoma cells. Zeaxanthin induced apoptosis in melanoma cells as indicated by annexin V and ethidium III flow cytometry. Western blot analysis demonstrated that zeaxanthin decreased the expression of antiapoptotic proteins (Bcl-2 and Bcl-xL) and increased the expression of proapoptotic proteins (Bak and Bax) in zeaxanthin-treated melanoma cells. Zeaxanthin increased mitochondrial permeability as determined by JC-1 fluorescein study. Zeaxanthin also increased the level of cytosol cytochrome c and caspase-9 and -3 activities, but not caspase-8, as measured by ELISA assay or colorimetric assay. All of these findings indicate that the intrinsic (mitochondrial) pathway is involved in zeaxanthin-induced apoptosis in uveal melanoma cells.

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Hesperidin Prevents High Glucose-Induced Damage of Retinal Pigment Epithelial Cells

Planta Medica ◽

10.1055/a-0601-7020 ◽

2018 ◽

Vol 84 (14) ◽

pp. 1030-1037 ◽

Cited By ~ 5

Author(s):

Wayne Liu ◽

Shorong-Shii Liou ◽

Tang-Yao Hong ◽

I-Min Liu

Keyword(s):

High Glucose ◽

Retinal Pigment Epithelial ◽

Colorimetric Assay ◽

Retinal Pigment ◽

Retinal Pigment Epithelial Cells ◽

Antioxidant Enzyme Activities ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Rpe Cells ◽

Pigment Epithelial

AbstractThe present study aimed to determine whether hesperidin, a plant-based active flavanone found in citrus fruits, can prevent high glucose-induced retinal pigment epithelial (RPE) cell impairment. Cultured human RPE cells (ARPE-19) were exposed to a normal glucose concentration (5.5 mM) for 4 d and then soaked in either normal (5.5 mM) or high (33.3 mM) concentrations of D-glucose with or without different concentrations of hesperidin (10, 20, or 40 µM) for another 48 h. The survival rates of the cells were measured using a 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide reduction assay. With the help of a fluorescent probe, the intracellular production of reactive oxygen species (ROS) was evaluated. Colorimetric assay kits were used to assess the antioxidant enzyme activities, and western blotting was used to measure the expression of apoptosis-related protein. Hesperidin was effective in inhibiting high glucose-induced ROS production, preventing loss of cell viability, and promoting the endogenous antioxidant defense components, including glutathione peroxidase, superoxide dismutase, catalase, and glutathione, in a concentration-dependent manner. Furthermore, high glucose triggered cell apoptosis via the upregulation of caspase-9/3, enhancement of cytochrome c release into the cytosol, and subsequent interruption of the Bax/Bcl-2 balance. These detrimental effects were ameliorated by hesperidin in a concentration-dependent manner. We conclude that through the scavenging of ROS and modulation of the mitochondria-mediated apoptotic pathway, hesperidin may protect RPE cells from high glucose-induced injury and thus may be a candidate in preventing the visual impairment caused by diabetic retinopathy.

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SMBA1, a Bax Activator, Induces Cell Cycle Arrest and Apoptosis in Malignant Glioma Cells

Pharmacology ◽

10.1159/000500292 ◽

2019 ◽

Vol 105 (3-4) ◽

pp. 164-172

Author(s):

Shuangbo Fan ◽

Qian Xu ◽

Liang Wang ◽

Yulin Wan ◽

Sheng Qiu

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Biological Effects ◽

Cyclin B1 ◽

Dependent Manner ◽

Apoptosis Pathway ◽

Cycle Arrest ◽

Intrinsic Apoptosis Pathway ◽

Induced Apoptosis ◽

Dose Dependent

SMBA1 (small-molecule Bax agonists 1), a small molecular activator of Bax, is a potential anti-tumour agent. In the present study, we investigated the biological effects of SMBA1 on glioblastoma (GBM) cells. SMBA1 reduced the viabilities of U87MG, U251 and T98G cells in a time- and dose-dependent manner. Moreover, treatment with SMBA1 induced cell cycle arrest at the G2/M phase transition, accompanied by the downregulation of Cdc25c and cyclin B1 and the upregulation of p21. SMBA1 also induced apoptosis of GBM cells in a dose-dependent manner. Mechanistically, SMBA1 induced apoptosis via the intrinsic pathway. Silencing of Bax or ectopic expression of Bcl-2 significantly inhibited SMBA1-induced apoptosis. Moreover, SMBA1 inhibited the growth of U87MG xenograft tumours in vivo. Overall, SMBA1 shows anti-proliferative effects against GBM cells through activation of the intrinsic apoptosis pathway.

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Subtoxic Levels of Apigenin Inhibit Expression and Secretion of VEGF by Uveal Melanoma Cells via Suppression of ERK1/2 and PI3K/Akt Pathways

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/817674 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Shih-Chun Chao ◽

Sheng-Chieh Huang ◽

Dan-Ning Hu ◽

Hung-Yu Lin

Keyword(s):

P38 Mapk ◽

Cell Lines ◽

Uveal Melanoma ◽

Culture Media ◽

Melanoma Cells ◽

Pcr Analysis ◽

Signal Pathways ◽

Dependent Manner ◽

Vegf Mrna ◽

Phosphorylated Akt

The effects of apigenin on the expression of VEGF in uveal melanoma cells have not been reported. We studied this effect and relevant signaling pathways in two human uveal melanoma cell lines (SP6.5 and C918). ELISA assay revealed that the constitutive secretion of VEGF by uveal melanoma cells was 21-fold higher than that in normal uveal melanocytes. Apigenin at subtoxic levels (1–5 μM) significantly suppressed the secretion of VEGF in a dose- and time-dependent manner in melanoma cells. VEGF levels in the conditioned culture media from SP6.5 and C918 cell lines treated with 5 μM apigenin for 24 h reduced to 29% and 21% of those in cells not treated with apigenin, respectively. RT-PCR analysis found that apigenin also decreased the expression of VEGF mRNA in melanoma cells. ELISA study of various signal pathways showed that apigenin significantly decreased phosphorylated Akt and ERK1/2 but increased phosphorylated JNK1/2 and p38 MAPK levels in melanoma cells. PI3K/Akt or ERK1/2 inhibitors significantly decreased, but JNK1/2 and p38 MAPK inhibitors did not influence the secretion of VEGF by melanoma cells, suggesting that apigenin suppresses the secretion of VEGF mainly through the inhibition of PI3K/Akt and ERK1/2 pathways.

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Lp16-PSP, A Member of YjgF/YER057c/UK114 Protein Family Induces Apoptosis and p21WAF1/CIP1 Mediated G1 Cell Cycle Arrest in Human Acute Promyelocytic Leukemia (APL) HL-60 Cells

10.20944/preprints201709.0119.v1 ◽

2017 ◽

Author(s):

Thomson Patrick Joseph ◽

Warren Chanda ◽

Abdullah Faqeer Mohammad ◽

Sadia Kanwal ◽

Samana Batool ◽

...

Keyword(s):

Cell Lines ◽

Lentinula Edodes ◽

Colorimetric Assay ◽

Leukemia Cell ◽

G1 Arrest ◽

Dependent Manner ◽

In Vivo Models ◽

Induction Of Apoptosis ◽

Induced Apoptosis

Lp16-PSP from Lentinula edodes strain C91-3 has been reported previously in our laboratory to have selective cytotoxic activity against a panel of human cell lines. Herein, we have used several parameters in order to characterize the Lp16-PSP-induced cell death using HL-60 as model cancer. The results of phase contrast microscopy, nuclear examination, DNA fragmentation detection and flow cytometry revealed that high doses of Lp16-PSP resulted in the induction of apoptosis in HL-60 cells. The colorimetric assay showed the activation of caspase-8, -9 and -3 cascade highlighting the involvement of Fas/FasL-related pathway. Whereas, western blot revealed the cleavage of caspase-3, increased expression of Bax, the release of cytochrome c and decreased expression of Bcl-2 in a dose-dependent manner, suggesting the intrinsic pathway might be involved in Lp16-PSP-induced apoptosis either. Low doses of Lp16-PSP resulted in the anchorage-independent growth inhibition, induction of G1 phase arrest accompanied by the increased expression of p21WAF1/CIP1 along with the decreased expression of cyclin D, E, and cdk6. Our findings suggest that induction of apoptosis and p21WAF1/CIP1 mediated G1 arrest might be one of the mechanisms of the action of Lp16-PSP, however, further investigations on multiple leukemia cell lines and in vivo models are of ultimate need.

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Design, Synthesis, and Evaluation of Novel 2-Methoxyestradiol Derivatives as Apoptotic Inducers through an Intrinsic Apoptosis Pathway

Biomolecules ◽

10.3390/biom10010123 ◽

2020 ◽

Vol 10 (1) ◽

pp. 123

Author(s):

Li-Xin Sheng ◽

Jiang-Yu Zhang ◽

Li Li ◽

Xiao Xie ◽

Xiao-An Wen ◽

...

Keyword(s):

Tumor Cells ◽

Cell Lines ◽

Proliferative Activity ◽

Inhibitory Concentration ◽

Dependent Manner ◽

Human Breast ◽

Apoptosis Pathway ◽

Single Access ◽

Intrinsic Apoptosis Pathway ◽

Mcf 7

In order to discover novel derivatives in the anti-tumor field, reported anti-tumor pharmacophores (uridine, uracil, and thymine) were combined with 2-methoxyestradiol, which has been characterized as having excellent biological properties in terms of anti-tumor activity. Thus, 20 hybrids were synthesized through etherification at the 17β-OH or 3-phenolic hydroxyl group of 2-methoxyestradiol, and evaluated for their biological activities against the human breast adenocarcinoma MCF-7 cell lines, human breast cancer MDA-MB-231 cell lines, and the normal human liver L-O2 cell lines. As a result, all the uridine derivatives and single-access derivatives of uracil/thymine possessed good anti-proliferative activity against tested tumor cells (half maximal inhibitory concentration values from 3.89 to 19.32 µM), while only one dual-access derivative (21b) of thymine possessed good anti-proliferative activity (half maximal inhibitory concentration ≈ 25 µM). Among them, the uridine derivative 11 and the single-access derivative of uracil 12a possessed good anti-proliferative selectivity against tested tumor cells. Furthermore, basic mechanism studies revealed that hybrids 11 and 12a could induce apoptosis in MCF-7 cells through mitochondrial pathway. These hybrids induced morphological changes in MCF-7 cells, causing mitochondrial depolarization. These two hybrids also had the following effects: arrest of the cell cycle at the G2 phase; up regulation of Apaf-1, Bax, and cytochrome c; down regulation of Bcl-2 and Bcl-xL for both mRNA and protein; and increase of the expression for caspase-8 and -9. Finally, apoptotic effector caspase-3 was increased, which eventually caused nuclear apoptosis at least through an intrinsic pathway in the mitochondria. Additionally, hybrids 11 and 12a could specifically bind to estradiol receptor alpha in a dose-dependent manner.

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Depletion of Survivin suppresses docetaxel-induced apoptosis in HeLa cells by facilitating mitotic slippage

Scientific Reports ◽

10.1038/s41598-021-81563-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Teng-Long Han ◽

Hang Sha ◽

Jun Ji ◽

Yun-Tian Li ◽

Deng-Shan Wu ◽

...

Keyword(s):

Hela Cells ◽

Spindle Assembly Checkpoint ◽

Spindle Assembly ◽

Clonogenic Survival ◽

Mitotic Arrest ◽

Apoptosis Pathway ◽

Mitotic Slippage ◽

Intrinsic Apoptosis Pathway ◽

Apoptosis Protein ◽

Induced Apoptosis

AbstractThe anticancer effects of taxanes are attributed to the induction of mitotic arrest through activation of the spindle assembly checkpoint. Cell death following extended mitotic arrest is mediated by the intrinsic apoptosis pathway. Accordingly, factors that influence the robustness of mitotic arrest or disrupt the apoptotic machinery confer drug resistance. Survivin is an inhibitor of apoptosis protein. Its overexpression is associated with chemoresistance, and its targeting leads to drug sensitization. However, Survivin also acts specifically in the spindle assembly checkpoint response to taxanes. Hence, the failure of Survivin-depleted cells to arrest in mitosis may lead to taxane resistance. Here we show that Survivin depletion protects HeLa cells against docetaxel-induced apoptosis by facilitating mitotic slippage. However, Survivin depletion does not promote clonogenic survival of tumor cells but increases the level of cellular senescence induced by docetaxel. Moreover, lentiviral overexpression of Survivin does not provide protection against docetaxel or cisplatin treatment, in contrast to the anti-apoptotic Bcl-xL or Bcl-2. Our findings suggest that targeting Survivin may influence the cell response to docetaxel by driving the cells through aberrant mitotic progression, rather than directly sensitizing cells to apoptosis.

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Cyanidin-3-glucoside attenuates 4-hydroxynonenal- and visible light-induced retinal damage in vitro and in vivo

Food & Function ◽

10.1039/c9fo00273a ◽

2019 ◽

Vol 10 (5) ◽

pp. 2871-2880 ◽

Cited By ~ 2

Author(s):

Yong Wang ◽

Wentao Qi ◽

Yazhen Huo ◽

Ge Song ◽

Hui Sun ◽

...

Keyword(s):

Retinal Pigment Epithelial ◽

Retinal Pigment ◽

Retinal Pigment Epithelial Cells ◽

Retinal Damage ◽

Protective Effects ◽

Pigment Epithelial ◽

Induced Apoptosis ◽

Pigment Epithelial Cells

Cyanidin-3-glucoside has efficient protective effects on 4-hydroxynonenal-induced apoptosis, senescence, and angiogenesis in retinal pigment epithelial cells.

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Role of Luteolin-Induced Apoptosis and Autophagy in Human Glioblastoma Cell Lines

Medicina ◽

10.3390/medicina57090879 ◽

2021 ◽

Vol 57 (9) ◽

pp. 879 ◽

Cited By ~ 1

Author(s):

Hye-Sung Lee ◽

Bong-Soo Park ◽

Hae-Mi Kang ◽

Jung-Han Kim ◽

Sang-Hun Shin ◽

...

Keyword(s):

Cell Lines ◽

Therapeutic Effects ◽

Dependent Manner ◽

Glioblastoma Cell ◽

Related Factors ◽

Green Pepper ◽

Real Time Quantitative Pcr ◽

Anti Inflammatory ◽

Induced Apoptosis ◽

Glioblastoma Cell Lines

Background and Objectives: Malignant glioblastoma (GBM) is caused by abnormal proliferation of glial cells, which are found in the brain. The therapeutic effects of surgical treatment, radiation therapy, and chemo-therapy against GBM are relatively poor compared with their effects against other tumors. Luteolin is abundant in peanut shells and is also found in herbs and other plants, such as thyme, green pepper, and celery. Luteolin is known to be effective against obesity and metabolic syndrome. The anti-inflammatory, and anti-cancer activities of luteolin have been investigated. Most studies have focused on the antioxidant and anti-inflammatory effects of luteolin, which is a natural flavonoid. However, the association between the induction of apoptosis by luteolin in GBM and autophagy has not yet been investigated. This study thus aimed to confirm the occurrence of luteolin-induced apoptosis and autophagy in GBM cells and to assess their relationship. Materials and Methods: A172 and U-373MG glioblastoma cell lines were used for this experiment. We confirmed the apoptosis effect of Luteolin on GBM cells using methods such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, immunofluorescence, Flow cytometry (FACS) western blot, and real-time quantitative PCR (qPCR). Results: In the luteolin-treated A172 and U-373MG cells, cell viability decreased in a concentration- and time-dependent manner. In addition, in A172 and U-373MG cells treated with luteolin at concentrations greater than 100 μM, nuclear fragmentation, which is a typical morphological change characterizing apoptosis, as well as fragmentation of caspase-3 and Poly (ADP-ribose) polymerase (PARP), which are apoptosis-related factors, were observed. Autophagy was induced after treatment with at least 50 μM luteolin. Inhibition of autophagy using 3MA allowed for a low concentration of luteolin to more effectively induce apoptosis in A172 and U-373MG cells. Conclusions: Results showed that luteolin induces apoptosis and autophagy and that the luteolin-induced autophagy promotes cell survival. Therefore, an appropriate combination therapy involving luteolin and an autophagy inhibitor is expected to improve the prognosis of GBM treatment.

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Cyclovirobuxine D Induces Apoptosis and Mitochondrial Damage in Glioblastoma Cells Through ROS-Mediated Mitochondrial Translocation of Cofilin

Frontiers in Oncology ◽

10.3389/fonc.2021.656184 ◽

2021 ◽

Vol 11 ◽

Author(s):

Lin Zhang ◽

Ruoqiu Fu ◽

Dongyu Duan ◽

Ziwei Li ◽

Bin Li ◽

...

Keyword(s):

Cell Lines ◽

Oxidant Stress ◽

Mitochondrial Damage ◽

Dependent Manner ◽

Mitochondrial Translocation ◽

Mitochondrial Superoxide ◽

Human Astrocytes ◽

Anti Cancer ◽

Normal Human ◽

Induced Apoptosis

BackgroundCyclovirobuxine D (CVBD), a steroidal alkaloid, has multiple pharmacological activities, including anti-cancer activity. However, the anti-cancer effect of CVBD on glioblastoma (GBM) has seldom been investigated. This study explores the activity of CVBD in inducing apoptosis of GBM cells, and examines the related mechanism in depth.MethodsGBM cell lines (T98G, U251) and normal human astrocytes (HA) were treated with CVBD. Cell viability was examined by CCK-8 assay, and cell proliferation was evaluated by cell colony formation counts. Apoptosis and mitochondrial superoxide were measured by flow cytometry. All protein expression levels were determined by Western blotting. JC-1 and CM-H2DCFDA probes were used to evaluate the mitochondrial membrane potential (MMP) change and intracellular ROS generation, respectively. The cell ultrastructure was observed by transmission electron microscope (TEM). Colocalization of cofilin and mitochondria were determined by immunofluorescence assay.ResultsCVBD showed a greater anti-proliferation effect on the GBM cell lines, T98G and U251, than normal human astrocytes in dose- and time-dependent manners. CVBD induced apoptosis and mitochondrial damage in GBM cells. We found that CVBD led to mitochondrial translocation of cofilin. Knockdown of cofilin attenuated CVBD-induced apoptosis and mitochondrial damage. Additionally, the generation of ROS and mitochondrial superoxide was also induced by CVBD in a dose-dependent manner. N-acetyl-L-cysteine (NAC) and mitoquinone (MitoQ) pre-treatment reverted CVBD-induced apoptosis and mitochondrial damage. MitoQ pretreatment was able to block the mitochondrial translocation of cofilin caused by CVBD.ConclusionsOur data revealed that CVBD induced apoptosis and mitochondrial damage in GBM cells. The underlying mechanism is related to mitochondrial translocation of cofilin caused by mitochondrial oxidant stress.

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Role of mitochondrial glucocorticoid receptor in glucocorticoid-induced apoptosis

Journal of Experimental Medicine ◽

10.1084/jem.20050433 ◽

2006 ◽

Vol 203 (1) ◽

pp. 189-201 ◽

Cited By ~ 87

Author(s):

Ronit Vogt Sionov ◽

Orly Cohen ◽

Shlomit Kfir ◽

Yael Zilberman ◽

Eitan Yefenof

Keyword(s):

T Cell ◽

Glucocorticoid Receptor ◽

Cell Lines ◽

Cell Types ◽

Thymic Epithelial Cells ◽

Dependent Manner ◽

Localization Signal ◽

Induced Apoptosis ◽

T Cell Lines

The mechanisms by which glucocorticoid receptor (GR) mediates glucocorticoid (GC)-induced apoptosis are unknown. We studied the role of mitochondrial GR in this process. Dexamethasone induces GR translocation to the mitochondria in GC-sensitive, but not in GC-resistant, T cell lines. In contrast, nuclear GR translocation occurs in all cell types. Thymic epithelial cells, which cause apoptosis of the PD1.6 T cell line in a GR-dependent manner, induce GR translocation to the mitochondria, but not to the nucleus, suggesting a role for mitochondrial GR in eliciting apoptosis. This hypothesis is corroborated by the finding that a GR variant exclusively expressed in the mitochondria elicits apoptosis of several cancer cell lines. A putative mitochondrial localization signal was defined to amino acids 558–580 of human GR, which lies within the NH2-terminal part of the ligand-binding domain. Altogether, our data show that mitochondrial and nuclear translocations of GR are differentially regulated, and that mitochondrial GR translocation correlates with susceptibility to GC-induced apoptosis.

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