A novel acylglycerol kinase that produces lysophosphatidic acid modulates cross talk with EGFR in prostate cancer cells

The bioactive phospholipids, lysophosphatidic acid (LPA) and phosphatidic acid (PA), regulate pivotal processes related to the pathogenesis of cancer. Here, we report characterization of a novel lipid kinase, designated acylglycerol kinase (AGK), that phosphorylates monoacylglycerol and diacylglycerol to form LPA and PA, respectively. Confocal microscopy and subcellular fractionation suggest that AGK is localized to the mitochondria. AGK expression was up-regulated in prostate cancers compared with normal prostate tissues from the same patient. Expression of AGK in PC-3 prostate cancer cells markedly increased formation and secretion of LPA. This increase resulted in concomitant transactivation of the EGF receptor and sustained activation of extracellular signal related kinase (ERK) 1/2, culminating in enhanced cell proliferation. AGK expression also increased migratory responses. Conversely, down-regulating expression of endogenous AGK inhibited EGF- but not LPA-induced ERK1/2 activation and progression through the S phase of the cell cycle. Hence, AGK can amplify EGF signaling pathways and may play an important role in the pathophysiology of prostate cancer.

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Critical role of acylglycerol kinase in epidermal growth factor-induced mitogenesis of prostate cancer cells

Biochemical Society Transactions ◽

10.1042/bst0331362 ◽

2005 ◽

Vol 33 (6) ◽

pp. 1362-1365 ◽

Cited By ~ 9

Author(s):

S. Spiegel ◽

S. Milstien

Keyword(s):

Prostate Cancer ◽

Growth Factor ◽

Epidermal Growth Factor ◽

Cancer Cells ◽

Cannabinoid Receptor ◽

Critical Role ◽

Prostate Cancer Cells ◽

Lipid Kinase ◽

Epidermal Growth ◽

Acylglycerol Kinase

The bioactive phospholipids, LPA (lysophosphatidic acid) and PA (phosphatidic acid), regulate pivotal processes related to the pathogenesis of cancer. Recently, we cloned a novel type of lipid kinase that phosphorylates monoacylglycerols (such as 2-arachidonoylglycerol, an endogenous cannabinoid receptor ligand) and diacylglycerols, to form LPA and PA, respectively. This AGK (acylglycerol kinase) is highly expressed in prostate cancer cell lines and the results reviewed here suggest that AGK might be a critical player in the initiation and progression of prostate cancer. Intriguingly, down-regulation of endogenous AGK inhibited EGF (epidermal growth factor), but not LPA-induced ERK1/2 (extracellular-signal-regulated kinase 1/2) activation and progression through the S-phase of the cell cycle. In this review, we will summarize the evidence demonstrating that AGK amplifies EGF growth signalling pathways that play an important role in the pathophysiology of prostate cancer. Because LPA has long been implicated as an autocrine and paracrine growth stimulatory factor for prostate cancer cells, the identification of this novel lipid kinase that regulates its production could provide new and useful targets for preventive or therapeutic measures.

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6-Thioguanine and Its Analogs Promote Apoptosis of Castration-Resistant Prostate Cancer Cells in a BRCA2-Dependent Manner

Cancers ◽

10.3390/cancers11070945 ◽

2019 ◽

Vol 11 (7) ◽

pp. 945 ◽

Cited By ~ 1

Author(s):

Luna Laera ◽

Nicoletta Guaragnella ◽

Sergio Giannattasio ◽

Loredana Moro

Keyword(s):

Prostate Cancer ◽

Cell Proliferation ◽

Cancer Cells ◽

Breast Cancer Susceptibility Gene ◽

Dependent Manner ◽

Castration Resistant Prostate Cancer ◽

Prostate Cancer Cells ◽

Normal Prostate ◽

Castration Resistant ◽

Prostate Cancers

Background: Mutations in the oncosuppressor gene BReast CAncer susceptibility gene 2 (BRCA2) predispose to aggressive forms of prostate cancer which show poor response to taxane-based therapy, the standard treatment for castration-resistant, aggressive prostate cancer. Herein, we addressed the question whether changes in BRCA2 expression, a potential surrogate marker for BRCA2 activity, may affect the response of castration-resistant prostate cancer cells to 6-thioguanine (6-TG), a thiopurine used in the treatment of haematological malignancies. Methods: Yeast, normal prostate cells and castration-resistant prostate cancer cells were treated with 6-TG or its analogues, in presence or absence of paclitaxel, or with olaparib, a poly-(ADP-ribose) polymerase (PARP) inhibitor currently in clinical trials for treatment of metastatic castration-resistant prostate cancer, and cell proliferation, apoptosis and androgen receptor (AR) levels were measured. Results: 6-TG inhibited cell proliferation in yeast, normal and castration-resistant prostate cancer cells but promoted apoptosis only in cancer cells. Suppression of BRCA2 expression by siRNA or shRNA increased the sensitivity to 6-TG- and olaparib-induced apoptosis but did not affect cancer cell response to taxane. Intriguingly, 6-TG reduced AR expression levels independently on BRCA2 expression. Instead, olaparib decreased AR levels only in BRCA2-knockdown prostate cancer cells. Notably, overexpression of BRCA2 resulted in resistance of castration-resistant prostate cancer cells to 6-TG-, taxane- and olaparib-based treatment but promoted sensitivity to apoptosis induced by 2-amino-6-bromopurine and 2,6–dithiopurine, two 6-TG analogues. Conclusions: Our results provide a pre-clinical rationale for the use of 6-TG in the treatment of BRCA2-deficient castration-resistant prostate cancers, and of certain 6-TG analogues for treatment of BRCA2-proficient prostate cancers.

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Cytostatic Action of Novel Histone Deacetylase Inhibitors in Androgen Receptor-Null Prostate Cancer Cells

Pharmaceuticals ◽

10.3390/ph14020103 ◽

2021 ◽

Vol 14 (2) ◽

pp. 103

Author(s):

Zohaib Rana ◽

Joel D. A. Tyndall ◽

Muhammad Hanif ◽

Christian G. Hartinger ◽

Rhonda J. Rosengren

Keyword(s):

Prostate Cancer ◽

Androgen Receptor ◽

Cancer Cells ◽

Hdac Inhibitors ◽

G1 Arrest ◽

Prostate Cancer Cells ◽

Prostate Tumors ◽

Normal Prostate ◽

Pc3 Cells ◽

Du145 Cells

Androgen receptor (AR)-null prostate tumors have been observed in 11–24% of patients. Histone deacetylases (HDACs) are overexpressed in prostate tumors. Therefore, HDAC inhibitors (Jazz90 and Jazz167) were examined in AR-null prostate cancer cell lines (PC3 and DU145). Both Jazz90 and Jazz167 inhibited the growth of PC3 and DU145 cells. Jazz90 and Jazz167 were more active in PC3 cells and DU145 cells in comparison to normal prostate cells (PNT1A) and showed a 2.45- and 1.30-fold selectivity and higher cytotoxicity toward DU145 cells, respectively. Jazz90 and Jazz167 reduced HDAC activity by ~60% at 50 nM in PC3 lysates. At 4 μM, Jazz90 and Jazz167 increased acetylation in PC3 cells by 6- to 8-fold. Flow cytometry studies on the cell phase distribution demonstrated that Jazz90 causes a G0/G1 arrest in AR-null cells, whereas Jazz167 leads to a G0/G1 arrest in DU145 cells. However, apoptosis only occurred at a maximum of 7% of the total cell population following compound treatments in PC3 and DU145 cells. There was a reduction in cyclin D1 and no significant changes in bcl-2 in DU145 and PC3 cells. Overall, the results showed that Jazz90 and Jazz167 function as cytostatic HDAC inhibitors in AR-null prostate cancer cells.

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AS1 expression in prostate cancer and its effects on proliferation and invasion of prostate cancer cells

Cancer Biomarkers ◽

10.3233/cbm-203021 ◽

2021 ◽

pp. 1-9

Author(s):

Yuxin Li ◽

Xiaohong Zhuang ◽

Li Zhuang ◽

Hongjian Liu

Keyword(s):

Prostate Cancer ◽

Cell Proliferation ◽

Cancer Cells ◽

Related Protein ◽

Prostate Cancer Cells ◽

Blank Group ◽

Normal Prostate ◽

Cell Cycles ◽

Prostate Cells ◽

Proliferation And Invasion

This paper aimed at investigating AS1 expression in prostate cancer (PCa) and its effects on the proliferation and invasion of prostate cancer cells (PCCs). The prostate tissues and the matched adjacent normal prostate tissues excised and preserved during radical prostatectomy in our hospital were collected. The LncRNA NCK1-AS1 expression was detected. PCa patients were followed up for three years to analyze their prognosis. The correlation of LncRNA NCK1-AS1 expression with clinicopathological features was analyzed. Human normal prostate cells and human PCCs were selected, in which LncRNA NCK1-AS1 expression was tested to screen and then transfect the cells. Cell proliferation, invasion and migration were detected. Cell cycles and apoptosis were analyzed. Compared with the adjacent normal tissues, LncRNA NCK1-AS1 was highly expressed in the prostate cancer tissues. Its expression was remarkably different in those with different stages of TNM and with lymphatic metastasis or not. The prognosis of patients with high LncRNA NCK1-AS1 expression was remarkably poorer than that of those with low expression. Compared with the human normal prostate cells, LncRNA NCK1-AS1 expression in the human PCCs remarkably rose, with the greatest difference in 22Rv1 cells. Compared with the Blank group, cell proliferation and the number of plate cloned cells remarkably reduced in the sh-NCK1-AS1 group. Additionally, in this group, the number of invasive and migratory cells remarkably reduced; the expression of invasion-related protein E-cadherin remarkably rose but that of MMP-2 remarkably reduced; cell cycles were arrested and the expression of cycle-related proteins (CDK4, CDK6, cyclin D1) remarkably reduced; the apoptotic rate and the expression of apoptosis-related protein Bax remarkably rose. LncRNA NCK1-AS1 is highly expressed in PCa, so its down-regulation can inhibit PCCs from proliferating and reduce the number of invasive cells.

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Recruitment of β-Catenin by Wild-Type or Mutant Androgen Receptors Correlates with Ligand-Stimulated Growth of Prostate Cancer Cells

Molecular Endocrinology ◽

10.1210/me.2003-0436 ◽

2004 ◽

Vol 18 (10) ◽

pp. 2388-2401 ◽

Cited By ~ 46

Author(s):

David Masiello ◽

Shao-Yong Chen ◽

Youyuan Xu ◽

Manon C. Verhoeven ◽

Eunis Choi ◽

...

Keyword(s):

Prostate Cancer ◽

Cell Growth ◽

Cancer Cells ◽

Nuclear Receptor ◽

Specific Antigen ◽

Prostate Cancer Cells ◽

Prostate Cell ◽

Nuclear Receptor Corepressor ◽

Prostate Cancers

Abstract Prostate cancers respond to treatments that suppress androgen receptor (AR) function, with bicalutamide, flutamide, and cyproterone acetate (CPA) being AR antagonists in clinical use. As CPA has substantial agonist activity, it was examined to identify AR coactivator/corepressor interactions that may mediate androgen-stimulated prostate cancer growth. The CPA-liganded AR was coactivated by steroid receptor coactivator-1 (SRC-1) but did not mediate N-C terminal interactions or recruit β-catenin, indicating a nonagonist conformation. Nonetheless, CPA did not enhance AR interaction with nuclear receptor corepressor, whereas the AR antagonist RU486 (mifepristone) strongly stimulated AR-nuclear receptor corepressor binding. The role of coactivators was further assessed with a T877A AR mutation, found in LNCaP prostate cancer cells, which converts hydroxyflutamide (HF, the active flutamide metabolite) into an agonist that stimulates LNCaP cell growth. The HF and CPA-liganded T877A ARs were coactivated by SRC-1, but only the HF-liganded T877A AR was coactivated by β-catenin. L-39, a novel AR antagonist that transcriptionally activates the T877A AR, but still inhibits LNCaP growth, similarly mediated recruitment of SRC-1 and not β-catenin. In contrast, β-catenin coactivated a bicalutamide-responsive mutant AR (W741C) isolated from a bicalutamide-stimulated LNCaP subline, further implicating β-catenin recruitment in AR-stimulated growth. Androgen-stimulated prostate-specific antigen gene expression in LNCaP cells could be modulated by β-catenin, and endogenous c-myc expression was repressed by dihydrotestosterone, but not CPA. These results indicate that interactions between AR and β-catenin contribute to prostate cell growth in vivo, although specific growth promoting genes positively regulated by AR recruitment of β-catenin remain to be identified.

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eIF5B regulates the expression of PD-L1 in prostate cancer cells by interacting with Wig1

BMC Cancer ◽

10.1186/s12885-021-08749-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Qi Li ◽

Mulun Xiao ◽

Yibo Shi ◽

Jinhao Hu ◽

Tianxiang Bi ◽

...

Keyword(s):

Prostate Cancer ◽

Cancer Cells ◽

Tumor Cells ◽

Translation Initiation ◽

Genetic Alterations ◽

Cell Counting ◽

Migration And Invasion ◽

Cell Group ◽

Prostate Cancer Cells ◽

Normal Prostate

Abstract Background Eukaryotic translation initiation factors (eIFs) are the key factors to synthesize translation initiation complexes during the synthesis of eukaryotic proteins. Besides, eIFs are especially important in regulating the immune function of tumor cells. However, the effect mechanism of eIFs in prostate cancer remains to be studied, which is precisely the purpose of this study. Methods In this study, three groups of prostate cancer cells were investigated. One group had its eIF5B gene knocked down; another group had its Programmed death 1 (PD-L1) overexpressed; the final group had its Wild-type p53-induced gene 1 (Wig1) overexpressed. Genetic alterations of the cancer cells were performed by plasmid transfection. The expression of PD-L1 mRNA was detected by quantitative real-time PCR (qRT-PCR), and the expressions of PD-L1 and eIF5B proteins were observed by western blot assays. Cell Counting Kit-8 (CCK-8), flow cytometry, Transwell and Transwell martrigel were used to investigated cell proliferation, apoptosis, migration and invasion, respectively. The effect of peripheral blood mononuclear cells (PBMCs) on tumor cells was observed, and the interaction between eIF5B and Wig1 was revealed by co-immunoprecipitation (CoIP) assay. Finally, the effects of interference with eIF5B expression on the growth, morphology, and immunity of the tumor, as well as PD-L1 expression in the tumor, were verified by tumor xenograft assays in vivo. Results Compared with normal prostate epithelial cells, prostate cancer cells revealed higher expressions of eIF5B and PD-L1 interference with eIF-5B expression can inhibit the proliferation, migration, invasion and PD-L1 expression of prostate cancer cells. Meanwhile, the cancer cell group with interference with eIF5B expression also demonstrated greater, apoptosis and higher vulnerability to PBMCs. CoIP assays showed that Wig1 could bind to eIF5B in prostate cancer cells, and its overexpression can inhibit the proliferation, migration, invasion and PD-L1 expression of cancer cells while promoting apoptosis. Moreover, interference with eIF5B expression can inhibit tumor growth, destroy tumor morphology, and suppress the proliferation of tumor cells. Conclusion eIF5B can promote the expression of PD-L1 by interacting with Wig1. Besides, interference with eIF5B expression can inhibit the proliferation, migration, invasion and immunosuppressive response of prostate cancer cells. This study proposes a new target, eIF5B, for immunotherapy of prostate cancer.

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Nuclear Kaiso Indicates Aggressive Prostate Cancers and Promotes Migration and Invasiveness of Prostate Cancer Cells

American Journal Of Pathology ◽

10.1016/j.ajpath.2012.08.008 ◽

2012 ◽

Vol 181 (5) ◽

pp. 1836-1846 ◽

Cited By ~ 36

Author(s):

Jacqueline Jones ◽

Honghe Wang ◽

Jianjun Zhou ◽

Shana Hardy ◽

Timothy Turner ◽

...

Keyword(s):

Prostate Cancer ◽

Cancer Cells ◽

Prostate Cancer Cells ◽

Prostate Cancers

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Allyl Isothiocyanate Induces Autophagy through the Up-Regulation of Beclin-1 in Human Prostate Cancer Cells

The American Journal of Chinese Medicine ◽

10.1142/s0192415x18500830 ◽

2018 ◽

Vol 46 (07) ◽

pp. 1625-1643 ◽

Cited By ~ 3

Author(s):

Hung-En Chen ◽

Ji-Fan Lin ◽

Te-Fu Tsai ◽

Yi-Chia Lin ◽

Kuang-Yu Chou ◽

...

Keyword(s):

Prostate Cancer ◽

Cancer Cells ◽

Allyl Isothiocyanate ◽

Beclin 1 ◽

Human Prostate ◽

Human Prostate Cancer ◽

Prostate Cancer Cells ◽

Normal Prostate ◽

Autophagy Induction ◽

Pc3 Cells

Allyl isothiocyanate (AITC), one of the most widely studied phytochemicals, inhibits the survival of human prostate cancer cells while minimally affecting normal prostate epithelial cells. Our study demonstrates the mechanism of AITC-induced cell death in prostate cancer cells. AITC induces autophagy in RV1 and PC3 cells, judging from the increased level of LC3-II protein in a dose- and time-dependent manner, but not in the normal prostate epithelial cell (PrEC). Inhibition of autophagy in AITC-treated cells decreased cell viability and enhanced apoptosis, suggesting that the autophagy played a protective role. There are several pathways activated in ATIC-treated cells. We detected the phosphorylation forms of mTOR, ERK, AMPK, JNK and p38, and ERK AMPK and JNK activation were also detected. However, inhibition of AITC-activated ERK, AMPK and JNK by pre-treatment of specific inhibitors did not alter autophagy induction. Finally, increased beclin-1 expression was detected in AITC-treated cells, and inhibition of AITC-induced beclin-1 attanuated autophagy induction, indicating that AITC-induced autophagy occurs through upregulating beclin-1. Overall, our data show for the first time that AITC induces protective autophagy in Rv1 and PC3 cells through upregulation of beclin-1. Our results could potentially contribute to a therapeutic application of AITC in prostate cancer patients.

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SOX30, a target gene of miR-653-5p, represses the proliferation and invasion of prostate cancer cells through inhibition of Wnt/β-catenin signaling

Cellular & Molecular Biology Letters ◽

10.1186/s11658-019-0195-4 ◽

2019 ◽

Vol 24 (1) ◽

Cited By ~ 4

Author(s):

Qiang Fu ◽

Zhenye Sun ◽

Fan Yang ◽

Tianci Mao ◽

Yanyao Gao ◽

...

Keyword(s):

Prostate Cancer ◽

Cancer Cells ◽

Cancer Cell ◽

Target Gene ◽

Prostate Cancer Cell ◽

Luciferase Reporter ◽

Prostate Cancer Cells ◽

Normal Prostate ◽

Proliferation And Invasion ◽

In Cells

Abstract Background Sex-determining region Y-box containing gene 30 (SOX30) is a newly identified tumor-associated gene in several types of cancer. However, whether SOX30 is involved in the development and progression of prostate cancer remains unknown. This study investigated the potential role of SOX30 in prostate cancer. Methods Prostate cancer cell lines and a normal prostate epithelial cell line were used for the experiments. The expression of SOX30 was determined using quantitative real-time PCR and western blot analysis. The malignant cellular behaviors of prostate cancer were assessed using the Cell Counting Kit-8, colony formation and Matrigel invasion assays. The miRNA–mRNA interaction was validated using the dual-luciferase reporter assay. Results SOX30 expression was lower in cells of prostate cancer lines than in cells of the normal prostate epithelial line. Its overexpression repressed the proliferation and invasion of prostate cancer cells. SOX30 was identified as a target gene of microRNA-653-5p (miR-653-5p), which is upregulated in prostate cancer tissues. MiR-653-5p overexpression decreased SOX30 expression, while its inhibition increased SOX30 expression in prostate cancer cells. MiR-653-5p inhibition also markedly restricted prostate cancer cell proliferation and invasion. SOX30 overexpression or miR-653-5p inhibition significantly reduced β-catenin expression and downregulated the activation of Wnt/β-catenin signaling. SOX30 knockdown significantly reversed the miR-653-5p inhibition-mediated inhibitory effect on the proliferation, invasion and Wnt/β-catenin signaling in prostate cancer cells. Conclusions These results reveal a tumor suppressive function for SOX30 in prostate cancer and confirmed the gene as a target of miR-653-5p. SOX30 upregulation due to miR-653-5p inhibition restricted the proliferation and invasion of prostate cancer cells, and this was associated with Wnt/β-catenin signaling suppression. These findings highlight the importance of the miR-653-5p–SOX30–Wnt/β-catenin signaling axis in prostate cancer progression.

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