scholarly journals The Omega-3 Polyunsaturated Fatty Acid DHA Induces Simultaneous Apoptosis and Autophagy via Mitochondrial ROS-Mediated Akt-mTOR Signaling in Prostate Cancer Cells Expressing Mutant p53

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Soyeon Shin ◽  
Kaipeng Jing ◽  
Soyeon Jeong ◽  
Nayeong Kim ◽  
Kyoung-Sub Song ◽  
...  

Docosahexaenoic acid (DHA) induces autophagy-associated apoptotic cell death in wild-type p53 cancer cells via regulation of p53. The present study investigated the effects of DHA on PC3 and DU145 prostate cancer cell lines harboring mutant p53. Results show that, in addition to apoptosis, DHA increased the expression levels of lipidated form LC3B and potently stimulated the autophagic flux, suggesting that DHA induces both autophagy and apoptosis in cancer cells expressing mutant p53. DHA led to the generation of mitochondrial reactive oxygen species (ROS), as shown by the mitochondrial ROS-specific probe mitoSOX. Similarly, pretreatment with the antioxidant N-acetyl-cysteine (NAC) markedly inhibited both the autophagy and the apoptosis triggered by DHA, indicating that mitochondrial ROS mediate the cytotoxicity of DHA in mutant p53 cells. Further, DHA reduced the levels of phospho-Akt and phospho-mTOR in a concentration-dependent manner, while NAC almost completely blocked that effect. Collectively, these findings present a novel mechanism of ROS-regulated apoptosis and autophagy that involves Akt-mTOR signaling in prostate cancer cells with mutant p53 exposed to DHA.

2013 ◽  
Vol 3 (3) ◽  
pp. 66 ◽  
Author(s):  
Vanessa Hörmann ◽  
Sivanesan Dhandayuthapani ◽  
James Kumi-Diaka ◽  
Appu Rathinavelu

Background: Prostate cancer is the second most common cancer in American men. The development of alternative preventative and/or treatment options utilizing a combination of phytochemicals and chemotherapeutic drugs could be an attractive alternative compared to conventional carcinoma treatments. Genistein isoflavone is the primary dietary phytochemical found in soy and has demonstrated anti-tumor activities in LNCaP prostate cancer cells. Topotecan Hydrochloride (Hycamtin) is an FDA-approved chemotherapy for secondary treatment of lung, ovarian and cervical cancers. The purpose of this study was to detail the potential activation of the intrinsic apoptotic pathway in LNCaP prostate cancer cells through genistein-topotecan combination treatments. Methods: LNCaP cells were cultured in complete RPMI medium in a monolayer (70-80% confluency) at 37ºC and 5% CO2. Treatment consisted of single and combination groups of genistein and topotecan for 24 hours. The treated cells were assayed for i) growth inhibition through trypan blue exclusion assay and microphotography, ii) classification of cellular death through acridine/ ethidium bromide fluorescent staining, and iii) activation of the intrinsic apoptotic pathway through Jc-1: mitochondrial membrane potential assay, cytochrome c release and Bcl-2 protein expression.Results: The overall data indicated that genistein-topotecan combination was significantly more efficacious in reducing the prostate carcinoma’s viability compared to the single treatment options. In all treatment groups, cell death occurred primarily through the activation of the intrinsic apoptotic pathway.Conclusion: The combination of topotecan and genistein has the potential to lead to treatment options with equal therapeutic efficiency as traditional chemo- and radiation therapies, but lower cell cytotoxicity and fewer side effects in patients. Key words: topotecan; genistein; intrinsic apoptotic cell death


2021 ◽  
Author(s):  
Dong-Lin Yang ◽  
Ya-jun Zhang ◽  
Liu-jun He ◽  
Chun-sheng Hu ◽  
Li-xia Gao ◽  
...  

Abstract Demethylzeylasteral (T-96), a pharmacologically active triterpenoid monomer extracted from Tripterygiumwilfordii Hook F (TWHF), has been reported to exhibit anti-neoplastic effect on several types of cancer cells. However,whether it has the anti-tumour capability in human Prostate cancer (CaP)cells and what’s the precise regulatory mechanisms underlying the anti-proliferation effect of T-96 on human CaP. In the current study, T-96 exerted significant cytotoxicity to CaP cells in vitro and induced cell cycle arrest at S-phase in a dose-dependent manner. Furthermore, mechanistic investigation indicated that through inducing endoplasmic reticulum (ER) stress caused by intracellular accumulation of reactive oxygen species (ROS), T-96 significantly promoted autophagy initiation while blocked the autophagic flux and finally caused extrinsic apoptosis in CaP cells, implying that ER stress induced byT-96 initiated caspase dependent apoptosis to inhibit CaP cells. Moreover, as a novel lethal ER stress inducer, T-96 was capable to enhance the sensitivity of CaP cells to chemotherapeutic drug cisplatin. Taken together, our data implied that T-96 is a novel ER stress and autophagy modulator, and has the potential applications for CaP therapy in clinic.


Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2722
Author(s):  
Ivan V. Maly ◽  
Wilma A. Hofmann

High fat consumption can enhance metastasis and decrease survival in prostate cancer, but the picture remains incomplete on the epidemiological and cell-biological level, impeding progress toward individualized recommendations in the clinic. Recent work has highlighted the role of exosomes secreted by prostate cancer cells in the progression of the disease, particularly in metastatic invasion, and also the utility of targeting these extracellular vesicles for diagnostics, as carriers of disease progression markers. Here, we investigated the question of a potential impact of the chief nutritional saturated fatty acid on the exosome secretion. Palmitic acid decreased the secretion of exosomes in human prostate cancer cells in vitro in a concentration-dependent manner. At the same time, the content of some prospective metastatic markers in the secreted exosomal fraction was also reduced, as was the ability of the cells to invade across extracellular matrix barriers. While by themselves our in vitro results imply that on the cell level, palmitic acid may be beneficial vis-à-vis the course of the disease, they also suggest that, by virtue of the decreased biomarker secretion, palmitic acid has the potential to cause unjustified deprioritization of treatment in obese and lipidemic men.


2019 ◽  
Vol 382 (1) ◽  
pp. 111456 ◽  
Author(s):  
Marcos P. Thomé ◽  
Luiza C. Pereira ◽  
Giovana R. Onzi ◽  
Francieli Rohden ◽  
Mariana Ilha ◽  
...  

2020 ◽  
Vol 19 ◽  
pp. 153303382094806
Author(s):  
Guangxing Tan ◽  
Lin Jiang ◽  
Gangqin Li ◽  
Kuan Bai

Objective: To explore the effect and the related mechanism of STAT3 inhibitor AG-490 on inhibiting the proliferation of prostate cancer cells. Methods: PC3 cells and DU145 cells were cultured stably and treated with AG-490 to detect the changes in the activity of PC3 cells and DU145 cells. Thirty 6-8 weeks male BALB/c nude mouse were randomly divided into a control group, a DMSO group, and an AG-490 group to detect differences in various indexes . Results: The overexpression of miR-503-5p depends on the activation of STAT3. After treatment with AG-490, The proliferation and invasion of PC3 cells and DU145 cells and the expression of miR-503-5p were all reduced. Luciferase reporter assay demonstrated that the target proteins of miR-503-5p include PDCD4, TIMP-3, and PTEN. After treatment with AG-490, the expression of PDCD4, TIMP-3, and PTEN in cells was significantly up-regulated. IL-6-induced overexpression of miR-503-5p and restored the expression of STAT3, demonstrating the correlation between STAT3 and miR-503-5p. AG-490 can inhibit tumor growth and induce tumor cell apoptosis in the PC3 BALB/c nude mouse xenograft model. Western blotting and immunohistochemical staining showed that the expression levels of STAT3, Ki67, Bcl-2 and MMP-2 in the AG-490 group were significantly reduced, and the expression of PDCD4, TIMP-3 and PTEN increased. Conclusion: AG-490 can inhibit the growth of prostate cancer cells in a miR-503-5p-dependent manner by targeting STAT3. AG-490 is expected to become a new candidate drug for the treatment of prostate cancer.


Nutrients ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 488 ◽  
Author(s):  
Yeong-Seon Won ◽  
Kwon-Il Seo

Prostate cancer is the most common cancer in Western countries. Recently, Asian countries are being affected by Western habits, which have had an important role in the rapid increase in cancer incidence. Sanggenol L (San L) is a natural flavonoid present in the root barks of Morus alba, which induces anti-cancer activities in ovarian cancer cells. However, the molecular and cellular mechanisms of the effects of sanggenol L on human prostate cancer cells have not been elucidated. In this study, we investigated whether sanggenol L exerts anti-cancer activity in human prostate cancer cells via apoptosis and cell cycle arrest. Sanggenol L induced caspase-dependent apoptosis (up-regulation of PARP and Bax or down-regulation of procaspase-3, -8, -9, Bid, and Bcl-2), induction of caspase-independent apoptosis (up-regulation of AIF and Endo G on cytosol), suppression of cell cycle (down-regulation of CDK1/2, CDK4, CDK6, cyclin D1, cyclin E, cyclin A, and cyclin B1 or up-regulation of p53 and p21), and inhibition of PI3K/Akt/mTOR signaling (down-regulation of PI3K, p-Akt, and p-mTOR) in prostate cancer cells. These results suggest the induction of apoptosis via suppression of PI3K/Akt/mTOR signaling and cell cycle arrest via activation of p53 in response to sanggenol L in prostate cancer cells.


2005 ◽  
Vol 83 (5) ◽  
pp. 637-643 ◽  
Author(s):  
Michael D Matchett ◽  
Shawna L MacKinnon ◽  
Marva I Sweeney ◽  
Katherine T Gottschall-Pass ◽  
Robert A.R Hurta

Regulation of the matrix metalloproteinases (MMPs), the major mediators of extracellular matrix (ECM) degradation, is crucial to regulate ECM proteolysis, which is important in metastasis. This study examined the effects of 3 flavonoid-enriched fractions (a crude fraction, an anthocyanin-enriched fraction, and a proanthocyanidin-enriched fraction), which were prepared from lowbush blueberries (Vaccinium angustifolium), on MMP activity in DU145 human prostate cancer cells in vitro. Using gelatin gel electrophoresis, MMP activity was evaluated from cells after 24-hr exposure to blueberry fractions. All fractions elicited an ability to decrease the activity of MMP-2 and MMP-9. Of the fractions tested, the proanthocyanidin-enriched fraction was found to be the most effective at inhibiting MMP activity in these cells. No induction of either necrotic or apoptotic cell death was noted in these cells in response to treatment with the blueberry fractions. These findings indicate that flavonoids from blueberry possess the ability to effectively decrease MMP activity, which may decrease overall ECM degradation. This ability may be important in controlling tumor metastasis formation.Key words: blueberry flavonoids, MMP activity, prostate cancer cells.


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