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Galal MA, Al-Rimawi M, Hajeer A, Dahman H, Alouch S, Aljada A. Metformin: A Dual-Role Player in Cancer Treatment and Prevention. Int J Mol Sci 2024; 25:4083. [PMID: 38612893 PMCID: PMC11012626 DOI: 10.3390/ijms25074083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/30/2024] [Accepted: 04/02/2024] [Indexed: 04/14/2024] Open
Abstract
Cancer continues to pose a significant global health challenge, as evidenced by the increasing incidence rates and high mortality rates, despite the advancements made in chemotherapy. The emergence of chemoresistance further complicates the effectiveness of treatment. However, there is growing interest in the potential of metformin, a commonly prescribed drug for type 2 diabetes mellitus (T2DM), as an adjuvant chemotherapy agent in cancer treatment. Although the precise mechanism of action of metformin in cancer therapy is not fully understood, it has been found to have pleiotropic effects, including the modulation of metabolic pathways, reduction in inflammation, and the regulation of cellular proliferation. This comprehensive review examines the anticancer properties of metformin, drawing insights from various studies conducted in vitro and in vivo, as well as from clinical trials and observational research. This review discusses the mechanisms of action involving both insulin-dependent and independent pathways, shedding light on the potential of metformin as a therapeutic agent for different types of cancer. Despite promising findings, there are challenges that need to be addressed, such as conflicting outcomes in clinical trials, considerations regarding dosing, and the development of resistance. These challenges highlight the importance of further research to fully harness the therapeutic potential of metformin in cancer treatment. The aims of this review are to provide a contemporary understanding of the role of metformin in cancer therapy and identify areas for future exploration in the pursuit of effective anticancer strategies.
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Affiliation(s)
- Mariam Ahmed Galal
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
- Department of Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 1QU, UK
| | - Mohammed Al-Rimawi
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
| | | | - Huda Dahman
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
| | - Samhar Alouch
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
| | - Ahmad Aljada
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia; (M.A.G.); (M.A.-R.); (H.D.); (S.A.)
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Wu Q, Ge XL, Geng ZK, Wu H, Yang JY, Cao SR, Yang AL. HuaChanSu suppresses the growth of hepatocellular carcinoma cells by interfering with pentose phosphate pathway through down-regulation of G6PD enzyme activity and expression. Heliyon 2024; 10:e25144. [PMID: 38322888 PMCID: PMC10844274 DOI: 10.1016/j.heliyon.2024.e25144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 01/20/2024] [Accepted: 01/22/2024] [Indexed: 02/08/2024] Open
Abstract
HuaChanSu is active water extracts from the skin of Bufo bufo gargarizans Cantor. It has been already used to treat clinical cancers including HCC (Hepatocellular carcinoma, HCC), however, the molecular mechanisms under HuaChanSu's anti-cancer effects remain unclear. PPP (Pentose phosphate pathway, PPP), the major source of ribose and NADPH (Nicotinamide adenine dinucleotide phosphate, NADPH), is always over-activated and particularly critical for tumor cells growth. In this study, firstly, we illustrate that HuaChanSu restrains the growth of human hepatoma cells. More importantly, we demonstrate that the expression of G6PD (Glucose-6-phosphate dehydrogenase, G6PD), the first rate-limiting enzyme of the PPP, is restrained in human hepatoma cells after treatment with HuaChanSu. Additionally, our results show that G6PD enzyme activity and dimer formation are inhibited by HuaChanSu. Furthermore, we find that HuaChanSu could inhibit NADPH production and nucleotide level. In addition, we identify that expression of PLK1 (Polo-like kinase 1, PLK1) is also reduced in response to HuaChanSu, and knockdown of PLK1 restrains enzyme activity and dimer formation of G6PD, but has no effect on G6PD protein level. Subsequently, we demonstrate that inhibition of G6PD could restrain the proliferation of tumor cells and enhance the inhibitory effect of HuaChanSu on cell proliferation of human hepatoma cells. In conclusion, for the first time, our study reveals that HuaChanSu interferes with PPP via suppression of G6PD expression and enzyme activity to restrain growth of tumor cells, and these results provide a novel insight for the anti-hepatoma mechanisms of HuaChanSu and promote the innovation of the research model of TCM. Moreover, the development of drugs targeting abnormal tumor metabolism is currently a hot topic, our works provide theoretical support for further drug development from HuaChanSu, meanwhile, the revelation of the new molecular mechanism also provides a new perspective for the study of the pathogenesis of liver cancer. Short abstract HuaChanSu suppresses expression of G6PD, the first rate-limiting enzyme of the PPP, restrains G6PD enzyme activity and dimer formation via inhibition of PLK1, knockdown of G6PD could impair the growth of human hepatoma cells and increase the blocking effect of HuaChanSu on cell proliferation of cancer cells. In addition, HuaChanSu restrains NADPH production and nucleotide level, implying the suppression of PPP flux. Our study suggests that HuaChanSu interferes with PPP via G6PD inhibition to exert anti-hepatoma effects.
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Affiliation(s)
| | | | | | - Hao Wu
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Jing-yi Yang
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Shi-rong Cao
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Ai-lin Yang
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
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Javed A, Özduman G, Altun S, Duran D, Yerli D, Özar T, Şimşek F, Sami Korkmaz K. Mitotic kinase inhibitors as Therapeutic Interventions for Prostate Cancer: Evidence from In vitro Studies. Endocr Metab Immune Disord Drug Targets 2023; 23:EMIDDT-EPUB-129979. [PMID: 36872354 DOI: 10.2174/1871530323666230303092243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 01/05/2023] [Accepted: 01/10/2023] [Indexed: 03/07/2023]
Abstract
Prostate cancer is one of the devastating diseases characterized by genetic changes leading to uncontrolled growth and metastasis of the cells of the prostate gland and affects men worldwide. Conventional hormonal and chemotherapeutic agents are effective in mitigating the disease if diagnosed at an early stage. All dividing eukaryotic cells require mitotic progression for the maintenance of genomic integrity in progeny populations. The protein kinases, upon activation and de-activation in an ordered fashion, lead to spatial and temporal regulation of the cell division process. The entry into mitosis along with the progression into sub-phases of mitosis is ensured due to the activity of mitotic kinases. These kinases include Polo-Like-Kinase 1 (PLK1), Aurora kinases, and Cyclin-Dependent-Kinase 1 (CDK1), among others. The mitotic kinases, among others, are usually overexpressed in many cancers and can be targeted using small molecule inhibitors to reduce the effects of these regulators on mechanisms, such as regulation of genomic integrity and mitotic fidelity. In this review, we attempted to discuss the appropriate functions of mitotic kinases revealed through cell culture studies and the impact of their respective inhibitors derived in pre-clinical studies. The review is designed to elucidate the growing field of small molecule inhibitors and their functional screening or mode of action at the cellular and molecular level in the context of Prostate Cancer. Therefore, studies performed specifically on cells of Prostatic-origin are narrated in this review, culminating in a comprehensive view of the specific field of mitotic kinases that can be targeted for therapy of Prostate cancer.
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Affiliation(s)
- Aadil Javed
- Department of Bioengineering, Faculty of Engineering, Ege University, Bornova, Izmir, Turkey
| | - Gülseren Özduman
- Department of Bioengineering, Faculty of Engineering, Ege University, Bornova, Izmir, Turkey
| | - Sevda Altun
- Department of Bioengineering, Faculty of Engineering, Ege University, Bornova, Izmir, Turkey
| | - Doğan Duran
- Department of Bioengineering, Faculty of Engineering, Ege University, Bornova, Izmir, Turkey
| | - Dilan Yerli
- Department of Bioengineering, Faculty of Engineering, Ege University, Bornova, Izmir, Turkey
| | - Tilbe Özar
- Department of Bioengineering, Faculty of Engineering, Ege University, Bornova, Izmir, Turkey
| | - Faruk Şimşek
- Department of Bioengineering, Faculty of Engineering, Ege University, Bornova, Izmir, Turkey
| | - Kemal Sami Korkmaz
- Department of Bioengineering, Faculty of Engineering, Ege University, Bornova, Izmir, Turkey
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Antitumor Effects of Poplar Propolis on DLBCL SU-DHL-2 Cells. Foods 2023; 12:foods12020283. [PMID: 36673375 PMCID: PMC9857396 DOI: 10.3390/foods12020283] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 12/27/2022] [Accepted: 01/02/2023] [Indexed: 01/11/2023] Open
Abstract
Propolis is resinous natural product produced by Western honeybees using beeswax and plant and bud exudates, which has a wide range of biological activities, including antioxidation, antibacterial, anti-inflammation, immune regulation, antitumor, and so on. Diffuse large B-cell lymphoma (DLBCL) is an aggressive cancer, and accounts for about 30% of all lymphomas. The effect of poplar propolis on DLBCL has not been reported. The IC50 of propolis on the proliferation of DLBCL SU-DHL-2 cell line and its proteins and gene expressions were detected by CCK-8 kit, label-free proteomic, and RT-PCR. The results showed that the IC50 of propolis at the 5 × l05/mL cell for 24 h was 5.729 μg/mL. Label-free-based proteomics analysis showed that there were 115 differentially expressed proteins (61 up-regulated and 54 down-regulated proteins) between IC50 dose-treated and solvent control groups. There were 32.47% differential proteins located in the nucleus, 20.78% in the cytoplasm, and 14.29% in mitochondria. The most significant different pathway (p = 0.0016) of protein enrichment was ferroptosis (including glutamate-cysteine ligase regulatory subunit, ferritin, and heme oxygenase). The relative expression trend of 17 of the total 22 genes selected according to proteomics results was in line with their encoded protein. The highest protein-protein interaction was serine/threonine-protein kinase PLK, which interacted with 16 differential proteins. In conclusion, poplar propolis inhibited SU-DHL-2 cells via ferroptosis pathway, accelerating cell death and down-regulated serine/threonine-protein kinase PLK1, affecting apoptosis of cell. This result provides a theoretical basis for the treatment of DLBCL using propolis.
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Han B, Sun Y, Zhang X, Yue P, Tian M, Yan D, Yin F, Qin B, Zhao Y. Exogenous proline enhances susceptibility of NSCLC to cisplatin via metabolic reprogramming and PLK1-mediated cell cycle arrest. Front Pharmacol 2022; 13:942261. [PMID: 35910374 PMCID: PMC9330219 DOI: 10.3389/fphar.2022.942261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 06/28/2022] [Indexed: 12/24/2022] Open
Abstract
The occurrence of cisplatin resistance is still the main factor limiting the therapeutic effect of non-small cell lung cancer (NSCLC). It is urgent to elucidate the resistance mechanism and develop novel treatment strategies. Targeted metabolomics was first performed to detect amino acids’ content in cisplatin-resistant cancer cells considering the relationship between tumour metabolic rearrangement and chemotherapy resistance and chemotherapy resistance. We discovered that levels of most amino acids were significantly downregulated, whereas exogenous supplementation of proline could enhance the sensitivity of NSCLC cells to cisplatin, evidenced by inhibited cell viability and tumour growth in vitro and xenograft models. In addition, the combined treatment of proline and cisplatin suppressed ATP production through disruption of the TCA cycle and oxidative phosphorylation. Furthermore, transcriptomic analysis identified the cell cycle as the top enriched pathway in co-therapy cells, accompanied by significant down-regulation of PLK1, a serine/threonine-protein kinase. Mechanistic studies revealed that PLK1 inhibitor (BI2536) and CDDP have synergistic inhibitory effects on NSCLC cells, and cells transfected with lentivirus expressing shPLK1 showed significantly increased toxicity to cisplatin. Inhibition of PLK1 inactivated AMPK, a primary regulator of cellular energy homeostasis, ultimately leading to cell cycle arrest via FOXO3A-FOXM1 axis mediated transcriptional inhibition in cisplatin-resistant cells. In conclusion, our study demonstrates that exogenous proline exerts an adjuvant therapeutic effect on cisplatin resistance, and PLK1 may be considered an attractive target for the clinical treatment of cisplatin resistance in NSCLC.
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Affiliation(s)
- Bingjie Han
- Department of Translational Medical Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- *Correspondence: Bingjie Han,
| | - Yuanyuan Sun
- Department of Translational Medical Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xiaofen Zhang
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Ping Yue
- Department of Translational Medical Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Meiling Tian
- Department of Translational Medical Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Dan Yan
- Department of Translational Medical Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Fanxiang Yin
- Department of Translational Medical Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Bo Qin
- Department of Translational Medical Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yi Zhao
- Department of Translational Medical Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Li Z, Ma Z, Xue H, Shen R, Qin K, Zhang Y, Zheng X, Zhang G. Chromatin Separation Regulators Predict the Prognosis and Immune Microenvironment Estimation in Lung Adenocarcinoma. Front Genet 2022; 13:917150. [PMID: 35873497 PMCID: PMC9305311 DOI: 10.3389/fgene.2022.917150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 05/23/2022] [Indexed: 11/24/2022] Open
Abstract
Background: Abnormal chromosome segregation is identified to be a common hallmark of cancer. However, the specific predictive value of it in lung adenocarcinoma (LUAD) is unclear. Method: The RNA sequencing and the clinical data of LUAD were acquired from The Cancer Genome Atlas (TACG) database, and the prognosis-related genes were identified. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) were carried out for functional enrichment analysis of the prognosis genes. The independent prognosis signature was determined to construct the nomogram Cox model. Unsupervised clustering analysis was performed to identify the distinguishing clusters in LUAD-samples based on the expression of chromosome segregation regulators (CSRs). The differentially expressed genes (DEGs) and the enriched biological processes and pathways between different clusters were identified. The immune environment estimation, including immune cell infiltration, HLA family genes, immune checkpoint genes, and tumor immune dysfunction and exclusion (TIDE), was assessed between the clusters. The potential small-molecular chemotherapeutics for the individual treatments were predicted via the connectivity map (CMap) database. Results: A total of 2,416 genes were determined as the prognosis-related genes in LUAD. Chromosome segregation is found to be the main bioprocess enriched by the prognostic genes. A total of 48 CSRs were found to be differentially expressed in LUAD samples and were correlated with the poor outcome in LUAD. Nine CSRs were identified as the independent prognostic signatures to construct the nomogram Cox model. The LUAD-samples were divided into two distinct clusters according to the expression of the 48 CSRs. Cell cycle and chromosome segregation regulated genes were enriched in cluster 1, while metabolism regulated genes were enriched in cluster 2. Patients in cluster 2 had a higher score of immune, stroma, and HLA family components, while those in cluster 1 had higher scores of TIDES and immune checkpoint genes. According to the hub genes highly expressed in cluster 1, 74 small-molecular chemotherapeutics were predicted to be effective for the patients at high risk. Conclusion: Our results indicate that the CSRs were correlated with the poor prognosis and the possible immunotherapy resistance in LUAD.
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Affiliation(s)
- Zhaoshui Li
- Qingdao Medical College, Qingdao University, Qingdao, China
- Cardiothoracic Surgery Department, Qingdao Hiser Hospital Affiliated to Qingdao University, Qingdao, China
| | - Zaiqi Ma
- Cardiothoracic Surgery Department, Qingdao Hiser Hospital Affiliated to Qingdao University, Qingdao, China
| | - Hong Xue
- Heart Center Department, Qingdao Hiser Hospital Affiliated to Qingdao University, Qingdao, China
| | - Ruxin Shen
- Qingdao Medical College, Qingdao University, Qingdao, China
| | - Kun Qin
- Qingdao Medical College, Qingdao University, Qingdao, China
| | - Yu Zhang
- Qingdao Medical College, Qingdao University, Qingdao, China
| | - Xin Zheng
- Cancer Center Department, Qingdao Hiser Hospital Affiliated to Qingdao University, Qingdao, China
- *Correspondence: Xin Zheng, ; Guodong Zhang,
| | - Guodong Zhang
- Thoracic Surgery Department, Shandong Cancer Hospital Affiliated to Shandong First Medical University, Jinan, China
- *Correspondence: Xin Zheng, ; Guodong Zhang,
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Mao F, Kong Y, Liu J, Rao X, Li C, Donahue K, Zhang Y, Jones K, Zhang Q, Xu W, Liu X. Diptoindonesin G antagonizes AR signaling and enhances the efficacy of antiandrogen therapy in prostate cancer. Prostate 2022; 82:917-932. [PMID: 35322879 PMCID: PMC9035130 DOI: 10.1002/pros.24336] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 11/22/2021] [Accepted: 12/14/2021] [Indexed: 01/27/2023]
Abstract
BACKGROUND The androgen receptor (AR) signaling pathway has been well demonstrated to play a crucial role in the development, progression, and drug resistance of prostate cancer. Although the current anti-androgen therapy could significantly benefit prostate cancer patients initially, the efficacy of the single drug usually lasts for a relatively short period, as drug resistance quickly emerges. METHODS We have performed an unbiased bioinformatics analysis using the RNA-seq results in 22Rv1 cells to identify the cell response toward Dip G treatment. The RNA-seq results were validated by qRT-PCR. Protein levels were detected by western blot or staining. Cell viability was measured by Aquabluer and colony formation assay. RESULTS Here, we identified that Diptoindonesin G (Dip G), a natural extracted compound, could promote the proteasome degradation of AR and polo-like kinase 1 (PLK1) through modulating the activation of CHIP E3 ligase. Administration of Dip G has shown a profound efficiency in the suppression of AR and PLK1, not only in androgen-dependent LNCaP cells but also in castration-resistant and enzalutamide-resistant cells in a CHIP-dependent manner. Through co-targeting the AR signaling, Dip G robustly improved the efficacy of HSP90 inhibitors and enzalutamide in both human prostate cancer cells and in vivo xenograft mouse model. CONCLUSIONS Our results revealed that Dip G-mediated AR degradation would be a promising and valuable therapeutic strategy in the clinic.
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Affiliation(s)
- Fengyi Mao
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Yifan Kong
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Jinghui Liu
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Xiongjian Rao
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Chaohao Li
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Kristine Donahue
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Yanquan Zhang
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Katelyn Jones
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Qiongsi Zhang
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Wei Xu
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Xiaoqi Liu
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA
- Markey Cancer Center, University of Kentucky, Lexington, KY 40506, USA
- To whom correspondence should be addressed: Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40506, USA. Tel: (859) 562-2006;
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Morale MG, Tamura RE, Rubio IGS. Metformin and Cancer Hallmarks: Molecular Mechanisms in Thyroid, Prostate and Head and Neck Cancer Models. Biomolecules 2022; 12:357. [PMID: 35327549 PMCID: PMC8945547 DOI: 10.3390/biom12030357] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 02/01/2023] Open
Abstract
Metformin is the most used drug for type 2 diabetes (T2DM). Its antitumor activity has been described by clinical studies showing reduced risk of cancer development in T2DM patients, as well as management of T2DM compared with those receiving other glucose-lowering drugs. Metformin has a plethora of molecular actions in cancer cells. This review focused on in vitro data on the action mechanisms of metformin on thyroid, prostate and head and neck cancer. AMPK activation regulating specific downstream targets is a constant antineoplastic activity in different types of cancer; however, AMPK-independent mechanisms are also relevant. In vitro evidence makes it clear that depending on the type of tumor, metformin has different actions; its effects may be modulated by different cell conditions (for instance, presence of HPV infection), or it may regulate tissue-specific factors, such as the Na+/I- symporter (NIS) and androgen receptors. The hallmarks of cancer are a set of functional features acquired by the cell during malignant development. In vitro studies show that metformin regulates almost all the hallmarks of cancer. Interestingly, metformin is one of these therapeutic agents with the potential to synergize with other chemotherapeutic agents, with low cost, low side effects and high positive consequences. Some questions are still challenging: Are metformin in vitro data able to translate from bench to bedside? Does metformin affect drug resistance? Can metformin be used as a generic anticancer drug for all types of tumors? Which are the specific actions of metformin on the peculiarities of each type of cancer? Several clinical trials are in progress or have been concluded for repurposing metformin as an anticancer drug. The continuous efforts in the field and future in vitro studies will be essential to corroborate clinical trials results and to elucidate the raised questions.
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Affiliation(s)
- Mirian Galliote Morale
- Department of Biological Sciences, Federal University of São Paulo, Diadema, Rua Pedro de Toledo 669, 11° Andar, São Paulo 04039-032, Brazil; (M.G.M.); (R.E.T.)
- Laboratory of Cancer Molecular Biology, Federal University of São Paulo, Rua Pedro de Toledo 669, 11° Andar, São Paulo 04039-032, Brazil
| | - Rodrigo Esaki Tamura
- Department of Biological Sciences, Federal University of São Paulo, Diadema, Rua Pedro de Toledo 669, 11° Andar, São Paulo 04039-032, Brazil; (M.G.M.); (R.E.T.)
- Laboratory of Cancer Molecular Biology, Federal University of São Paulo, Rua Pedro de Toledo 669, 11° Andar, São Paulo 04039-032, Brazil
| | - Ileana Gabriela Sanchez Rubio
- Department of Biological Sciences, Federal University of São Paulo, Diadema, Rua Pedro de Toledo 669, 11° Andar, São Paulo 04039-032, Brazil; (M.G.M.); (R.E.T.)
- Laboratory of Cancer Molecular Biology, Federal University of São Paulo, Rua Pedro de Toledo 669, 11° Andar, São Paulo 04039-032, Brazil
- Thyroid Molecular Sciences Laboratory, Federal University of São Paulo, Rua Pedro de Toledo 669, 11° Andar, São Paulo 04039-032, Brazil
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Korns J, Liu X, Takiar V. A review of Plks: Thinking outside the (polo) box. Mol Carcinog 2022; 61:254-263. [PMID: 35049091 DOI: 10.1002/mc.23388] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/07/2021] [Accepted: 12/07/2021] [Indexed: 12/19/2022]
Abstract
The polo-like kinase (Plk) family is comprised of five different members (Plk1-5), each with their own distinct functions. Plk family members participate in pivotal cell division processes as well as in non-mitotic roles. Importantly, Plk expression has been correlated with various disease states, including cancer. Multiples therapies, which primarily target Plk1, are currently being investigated alone or in combination with other agents for clinical use in different cancers. As the role of Plks in disease progression becomes more prominent, it is important to outline their functions as cell cycle regulators and more. This review summarizes the structure and both mitotic and non-mitotic functions of each of the five Plk family members, sequentially. Additionally, the proposed mechanisms for how Plks contribute to tumorigenesis and the therapeutics currently under investigation are outlined.
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Affiliation(s)
- Julianna Korns
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnat, Ohio, USA
| | - Xiaoqi Liu
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Vinita Takiar
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnat, Ohio, USA.,Cincinnati VA Medical Center, Cincinnati, Ohio, USA
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Tseng CH. The Effect of Metformin on Male Reproductive Function and Prostate: An Updated Review. World J Mens Health 2021; 40:11-29. [PMID: 33831975 PMCID: PMC8761231 DOI: 10.5534/wjmh.210001] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 01/18/2021] [Accepted: 01/22/2021] [Indexed: 12/02/2022] Open
Abstract
Metformin is the first-line oral antidiabetic drug that shows multiple pleiotropic effects of anti-inflamation, anti-cancer, anti-aging, anti-microbia, anti-atherosclerosis, and immune modulation. Metformin's effects on men's related health are reviewed here, focusing on reproductive health under subtitles of erectile dysfunction (ED), steroidogenesis and spermatogenesis; and on prostate-related health under subtitles of prostate specific antigen (PSA), prostatitis, benign prostate hyperplasia (BPH), and prostate cancer (PCa). Updated literature suggests a potential role of metformin on arteriogenic ED but controversial and contradictory effects (either protective or harmful) on testicular functions of testosterone synthesis and spermatogenesis. With regards to prostate-related health, metformin use may be associated with lower levels of PSA in humans, but its clinical implications require more research. Although there is a lack of research on metform's effect on prostatitis, it may have potential benefits through its anti-microbial and anti-inflammatory properties. Metformin may reduce the risk of BPH by inhibiting the insulin-like growth factor 1 pathway and some but not all studies suggest a protective role of metformin on the risk of PCa. Many clinical trials are being conducted to investigate the use of metformin as an adjuvant therapy for PCa but results currently available are not conclusive. While some trials suggest a benefit in reducing the metastasis and recurrence of PCa, others do not show any benefit. More research works are warranted to illuminate the potential usefulness of metformin in the promotion of men's health.
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Affiliation(s)
- Chin Hsiao Tseng
- Department of Internal Medicine, National Taiwan University College of Medicine, Taipei, Taiwan.,Division of Endocrinology and Metabolism, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.,Division of Environmental Health and Occupational Medicine of the National Health Research Institutes, Zhunan, Taiwan.
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11
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Raab CA, Raab M, Becker S, Strebhardt K. Non-mitotic functions of polo-like kinases in cancer cells. Biochim Biophys Acta Rev Cancer 2021; 1875:188467. [PMID: 33171265 DOI: 10.1016/j.bbcan.2020.188467] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/03/2020] [Accepted: 11/03/2020] [Indexed: 12/12/2022]
Abstract
Inhibitors of mitotic protein kinases are currently being developed as non-neurotoxic alternatives of microtubule-targeting agents (taxanes, vinca alkaloids) which provide a substantial survival benefit for patients afflicted with different types of solid tumors. Among the mitotic kinases, the cyclin-dependent kinases, the Aurora kinases, the kinesin spindle protein and Polo-like kinases (PLKs) have emerged as attractive targets of cancer therapeutics. The functions of mammalian PLK1-5 are traditionally linked to the regulation of the cell cycle and to the stress response. Especially the key role of PLK1 and PLK4 in cellular growth and proliferation, their overexpression in multiple types of human cancer and their druggability, make them appealing targets for cancer therapy. Inhibitors for PLK1 and PLK4 are currently being tested in multiple cancer trials. The clinical success of microtubule-targeting agents is attributed not solely to the induction of a mitotic arrest in cancer cells, but also to non-mitotic effects like targeting intracellular trafficking on microtubules. This raises the question whether new cancer targets like PLK1 and PLK4 regulate critical non-mitotic functions in tumor cells. In this article we summarize the important roles of PLK1-5 for the regulation of non-mitotic signaling. Due to these functions it is conceivable that inhibitors for PLK1 or PLK4 can target interphase cells, which underscores their attractive potential as cancer drug targets. Moreover, we also describe the contribution of the tumor-suppressors PLK2, PLK3 and PLK5 to cancer cell signaling outside of mitosis. These observations highlight the urgent need to develop highly specific ATP-competitive inhibitors for PLK4 and for PLK1 like the 3rd generation PLK-inhibitor Onvansertib to prevent the inhibition of tumor-suppressor PLKs in- and outside of mitosis. The remarkable feature of PLKs to encompass a unique druggable domain, the polo-box-domain (PBD) that can be found only in PLKs offers the opportunity for the development of inhibitors that target PLKs exclusively. Beyond the development of mono-specific ATP-competitive PLK inhibitors, the PBD as drug target will support the design of new drugs that eradicate cancer cells based on the mitotic and non-mitotic function of PLK1 and PLK4.
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Affiliation(s)
| | - Monika Raab
- Department of Gynecology, Goethe-University, Frankfurt, Germany
| | - Sven Becker
- Department of Gynecology, Goethe-University, Frankfurt, Germany
| | - Klaus Strebhardt
- Department of Gynecology, Goethe-University, Frankfurt, Germany; German Cancer Consortium (DKTK), German Cancer Research Center, Partner Site Frankfurt am Main, Frankfurt, Germany.
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12
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Immune-related biomarker risk score predicts prognosis in prostate cancer. Aging (Albany NY) 2020; 12:22776-22793. [PMID: 33197890 PMCID: PMC7746334 DOI: 10.18632/aging.103921] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 07/25/2020] [Indexed: 12/23/2022]
Abstract
In this study, we constructed a model using a Cox proportional hazards model based on the expression of eight immune-related genes that were associated with prognosis in prostate cancer: EDNRB, ANGPTL2, TNFSF15, TNFRSF10D, EDN2, BMP2, NLRP14, and PLK1. We then identified associations between risk scores calculated with the model, tumor microenvironment characteristics, and immune cell infiltration. Prostate cancer patients in the high score group had poorer prognoses, and validation with the external GSE54460 dataset confirmed that the scoring model predicted biochemical recurrence with AUC values of 0.749 at 1 year, 0.804 at 3 years, and 0.774 at 5 years. Proportions of infiltrated M2 macrophages and regulatory T cells were increased in the high risk group, while CD8+ T cells were increased in the low risk group. Network analysis revealed that PLK1 may be a key regulator of the immune-suppressive microenvironment in prostate cancer. Double immunofluorescence labeling of a prostate cancer tissue microarray indicated that PLK1 expression correlated positively with numbers of infiltrating macrophages. These results indicate that an immune- related, gene-based risk score effectively reflects immune microenvironment characteristics and predicts prognosis in prostate cancer.
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13
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Kong Y, Zhang Y, Mao F, Zhang Z, Li Z, Wang R, Liu J, Liu X. Inhibition of EZH2 Enhances the Antitumor Efficacy of Metformin in Prostate Cancer. Mol Cancer Ther 2020; 19:2490-2501. [PMID: 33024029 DOI: 10.1158/1535-7163.mct-19-0874] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 01/06/2020] [Accepted: 09/24/2020] [Indexed: 11/16/2022]
Abstract
Upregulation of EZH2 is associated with advanced stage and poor prognosis of prostate cancer; therefore, it is likely to be a promising therapeutic target. Metformin, a drug that has been used to treat type 2 diabetes, was found to have antineoplastic activity in different cancers. Herein, we report that the combination of metformin and the EZH2 inhibitor GSK126 exerts synergistic inhibition on prostate cancer cell growth, both in vitro and in vivo Mechanistically, we identify that metformin can reduce EZH2 expression through upregulating miR-26a-5p, which is antagonized by androgen receptor (AR). Furthermore, we show that AR binds to the promoter of miR-26a-5p and suppresses its transcription. Although metformin can remove AR from the miR-26a-5p promoter, the interaction between AR and EZH2, which usually exists in androgen-refractory prostate cancer cells, strongly impedes the removal. However, GSK126 can inhibit the methyltransferase-dependent interaction between AR and EZH2, thus restoring metformin's efficacy in androgen-refractory prostate cancer cells. Collectively, our finding suggests that the combination of metformin and GSK126 would be an effective approach for future prostate cancer therapy, and particularly effective for AR-positive castration-resistant prostate cancer.
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Affiliation(s)
- Yifan Kong
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky.,Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Yanquan Zhang
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
| | - Fengyi Mao
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky.,Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Zhuangzhuang Zhang
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
| | - Zhiguo Li
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
| | - Ruixin Wang
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
| | - Jinghui Liu
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
| | - Xiaoqi Liu
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky. .,Markey Cancer Center, University of Kentucky, Lexington, Kentucky
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14
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Yu J, Xu H, Cui J, Chen S, Zhang H, Zou Y, Zhao J, Le S, Jiang L, Chen Z, Liu H, Zhang D, Xia J, Wu J. PLK1 Inhibition alleviates transplant-associated obliterative bronchiolitis by suppressing myofibroblast differentiation. Aging (Albany NY) 2020; 12:11636-11652. [PMID: 32541091 PMCID: PMC7343459 DOI: 10.18632/aging.103330] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 04/17/2020] [Indexed: 12/12/2022]
Abstract
Chronic allograft dysfunction (CAD) resulting from fibrosis is the major limiting factor for long-term survival of lung transplant patients. Myofibroblasts promote fibrosis in multiple organs, including the lungs. In this study, we identified PLK1 as a promoter of myofibroblast differentiation and investigated the mechanism by which its inhibition alleviates transplant-associated obliterative bronchiolitis (OB) during CAD. High-throughput bioinformatic analyses and experiments using the murine heterotopic tracheal transplantation model revealed that PLK1 is upregulated in grafts undergoing CAD as compared with controls, and that inhibiting PLK1 alleviates OB in vivo. Inhibition of PLK1 in vitro reduced expression of the specific myofibroblast differentiation marker α-smooth muscle actin (α-SMA) and decreased phosphorylation of both MEK and ERK. Importantly, we observed a similar phenomenon in human primary fibroblasts. Our results thus highlight PLK1 as a promising therapeutic target for alleviating transplant-associated OB through suppression of TGF-β1-mediated myofibroblast differentiation.
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Affiliation(s)
- Jizhang Yu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Heng Xu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Jikai Cui
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Shanshan Chen
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Hao Zhang
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Yanqiang Zou
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Jing Zhao
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Sheng Le
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Lang Jiang
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Zhang Chen
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Hao Liu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Dan Zhang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Jiahong Xia
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Jie Wu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
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15
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Wang X, Li B, Ciotkowska A, Rutz B, Erlander MG, Ridinger M, Wang R, Tamalunas A, Waidelich R, Stief CG, Hennenberg M. Onvansertib, a polo-like kinase 1 inhibitor, inhibits prostate stromal cell growth and prostate smooth muscle contraction, which is additive to inhibition by α 1-blockers. Eur J Pharmacol 2020; 873:172985. [PMID: 32017934 DOI: 10.1016/j.ejphar.2020.172985] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 01/15/2020] [Accepted: 01/31/2020] [Indexed: 02/02/2023]
Abstract
Prostate smooth muscle contraction and prostate enlargement contribute to lower urinary tract symptoms suggestive of benign prostatic hyperplasia. Recent evidence demonstrated that inhibitors for polo-like kinases (PLKs) inhibit smooth muscle contraction of human prostate tissues. However, their additive effects to α1-blockers, and effects on prostate growth are unknown. Here, we examined effects of a novel and highly selective PLK1 inhibitor, onvansertib on prostate smooth muscle contraction alone and in combination with α1-blockers, and on proliferation and viability of prostate stromal cells (WPMY-1). Prostate tissues were obtained from radical prostatectomy. Contractions were studied in an organ bath. Proliferation and viability were assessed by plate colony, EdU, and CCK-8 assay. Electric field stimulation (EFS)-induced contractions of human prostate tissues were inhibited to 34% by 100 nM and 1 μM onvansertib at 32 Hz, and to 48% and 47% by the α1-blockers tamsulosin and silodosin. Combination of onvansertib with tamsulosin or silodosin further reduced EFS-induced contractions in comparison to α1-blockers alone (59% and 61% respectively), and to onvansertib alone (68% for both). Noradrenaline-, phenylephrine-, methoxamine-, endothelin-1-, and ATP-induced contractions were inhibited by onvansertib (100 nM) to similar extent. Viability and proliferation of WPMY-1 cells were reduced in a concentration- and time-dependent manner (24-72 h, 10-100 nM). Onvansertib inhibits neurogenic, adrenergic, and endothelin-1- and ATP-induced contractions of human prostate smooth muscle, and proliferation of stromal cells. Contractions are reduced not more than 50% by α1-blockers. Combination of α1-blockers with onvansertib provides additive inhibition of prostate contractions.
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Affiliation(s)
- Xiaolong Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Bingsheng Li
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Anna Ciotkowska
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Beata Rutz
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | | | | | - Ruixiao Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | | | | | - Christian G Stief
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Martin Hennenberg
- Department of Urology, University Hospital, LMU Munich, Munich, Germany.
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16
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Chen Z, Chai Y, Zhao T, Li P, Zhao L, He F, Lang Y, Qin J, Ju H. Effect of PLK1 inhibition on cisplatin-resistant gastric cancer cells. J Cell Physiol 2019; 234:5904-5914. [PMID: 30488440 DOI: 10.1002/jcp.26777] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/27/2018] [Indexed: 01/20/2023]
Abstract
OBJECTIVE This study aims to investigate the effect of polo-like kinase 1 (PLK1) inhibition on cisplatin (DDP)-resistant gastric cancer (GC) cells. METHODS The transcriptional level of PLK1 was measured by quantitative reverse-transcription polymerase chain reaction. Expressions of PLK1 and its downstream mediators as well as autophagy-related protein LC3 I/LC3 II were detected by western blot. An 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 5-ethynyl-2'-deoxyuridine immunofluorescent staining were conducted to evaluate the cell viability and replication activity separately. Flow cytometry was carried out to determine the cell cycle status. The GFP-LC3 vector contributed toward tracking the formation and aggregation of autophagosomes. RESULTS Drug-resistant SGC-7901/DDP cells showed insignificant changes in all phases after DDP treatment, including DNA replication, cell proliferation, cell cycle, and apoptosis, whereas DDP could significantly improve the autophagy level of SGC-7901/DDP as well as PLK1expression. By downregulating the expression of PLK1, both BI2536 andsi-PLK1 enhanced SGC-7901/DDP sensitivity to DDP, suppressing the proliferation and autophagy as well as improving the apoptosis rate. PLK1 inhibition also resulted in the repression of cell division regulators CDC25C and cyclin B1. CONCLUSION Together, our experimental results illustrated that the DDP resistance of GC cells might be associated with the aberrant overexpression of PLK1. PLK1 inhibition, including si-PLK1 and BI2536 treatment, could restore the chemosensitivity of drug-resistant SGC-7901/DDP cells and enhance the efficacy of DDP, revealing the potential value of PLK1 inhibition in GC chemotherapy.
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Affiliation(s)
- Zihao Chen
- Graduate School of Hebei Medical University, Shijiazhuang, China
- The Third Department of Surgery, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | - Yanling Chai
- The Department of Respiratory Medicine, Second Ward, The Second Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Ting Zhao
- Graduate School of Hebei Medical University, Shijiazhuang, China
| | - Ping Li
- School of Medicine, Kunming University, Kunming, China
| | - Lihua Zhao
- School of Medicine, Kunming University, Kunming, China
| | - Fang He
- School of Medicine, Kunming University, Kunming, China
| | - Yu Lang
- School of Medicine, Kunming University, Kunming, China
| | - Jing Qin
- School of Medicine, Kunming University, Kunming, China
- The Respiratory System Disease Prevention and Control of Public Service Platform of Science and Technology in Yunnan Province, Kunming, China
| | - Hongping Ju
- School of Medicine, Kunming University, Kunming, China
- The Respiratory System Disease Prevention and Control of Public Service Platform of Science and Technology in Yunnan Province, Kunming, China
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17
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Inhibition of Polo-like Kinase 1 Prevents the Male Pronuclear Formation Via Alpha-tubulin Recruiting in In Vivo-fertilized Murine Embryos. JOURNAL OF ANIMAL REPRODUCTION AND BIOTECHNOLOGY 2018. [DOI: 10.12750/jet.2018.33.4.229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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18
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Fucic A, Aghajanyan A, Culig Z, Le Novere N. Systems Oncology: Bridging Pancreatic and Castrate Resistant Prostate Cancer. Pathol Oncol Res 2018; 25:1269-1277. [PMID: 30220022 DOI: 10.1007/s12253-018-0467-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 09/03/2018] [Indexed: 12/31/2022]
Abstract
Large investments by pharmaceutical companies in the development of new antineoplastic drugs have not been resulting in adequate advances of new therapies. Despite the introduction of new methods, technologies, translational medicine and bioinformatics, the usage of collected knowledge is unsatisfactory. In this paper, using examples of pancreatic ductal adenocarcinoma (PaC) and castrate-resistant prostate cancer (CRPC), we proposed a concept showing that, in order to improve applicability of current knowledge in oncology, the re-clustering of clinical and scientific data is crucial. Such an approach, based on systems oncology, would include bridging of data on biomarkers and pathways between different cancer types. Proposed concept would introduce a new matrix, which enables combining of already approved therapies between cancer types. Paper provides a (a) detailed analysis of similarities in mechanisms of etiology and progression between PaC and CRPC, (b) diabetes as common hallmark of both cancer types and (c) knowledge gaps and directions of future investigations. Proposed horizontal and vertical matrix in cancer profiling has potency to improve current antineoplastic therapy efficacy. Systems biology map using Systems Biology Graphical Notation Language is used for summarizing complex interactions and similarities of mechanisms in biology of PaC and CRPC.
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Affiliation(s)
- A Fucic
- Institute for Medical Research and Occupational Health, Ksaverska c 2, 10000, Zagreb, Croatia.
| | - A Aghajanyan
- Institute of Medicine, Peoples' Friendship University of Russia, Moscow, Russian Federation
| | - Z Culig
- Department of Urology, Medical University of Innsbruck, Innsbruck, Austria
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19
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Mao F, Li J, Luo Q, Wang R, Kong Y, Carlock C, Liu Z, Elzey BD, Liu X. Plk1 Inhibition Enhances the Efficacy of BET Epigenetic Reader Blockade in Castration-Resistant Prostate Cancer. Mol Cancer Ther 2018; 17:1554-1565. [PMID: 29716963 PMCID: PMC6030429 DOI: 10.1158/1535-7163.mct-17-0945] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 02/07/2018] [Accepted: 04/25/2018] [Indexed: 01/30/2023]
Abstract
Polo-like kinase 1 (Plk1), a crucial regulator of cell-cycle progression, is overexpressed in multiple types of cancers and has been proven to be a potent and promising target for cancer treatment. In case of prostate cancer, we once showed that antineoplastic activity of Plk1 inhibitor is largely due to inhibition of androgen receptor (AR) signaling. However, we also discovered that Plk1 inhibition causes activation of the β-catenin pathway and increased expression of c-MYC, eventually resulting in resistance to Plk1 inhibition. JQ1, a selective small-molecule inhibitor targeting the amino-terminal bromodomains of BRD4, has been shown to dramatically inhibit c-MYC expression and AR signaling, exhibiting antiproliferative effects in a range of cancers. Because c-MYC and AR signaling are essential for prostate cancer initiation and progression, we aim to test whether targeting Plk1 and BRD4 at the same time is an effective approach to treat prostate cancer. Herein, we show that a combination of Plk1 inhibitor GSK461364A and BRD4 inhibitor JQ1 had a strong synergistic effect on castration-resistant prostate cancer (CRPC) cell lines, as well as in CRPC xenograft tumors. Mechanistically, the synergistic effect is likely due to two reasons: (i) Plk1 inhibition results in the accumulation of β-catenin in the nucleus, thus elevation of c-MYC expression, whereas JQ1 treatment directly suppresses c-MYC transcription; (ii) Plk1 and BRD4 dual inhibition acts synergistically in inhibition of AR signaling. Mol Cancer Ther; 17(7); 1554-65. ©2018 AACR.
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Affiliation(s)
- Fengyi Mao
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Jie Li
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Qian Luo
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Ruixin Wang
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Yifan Kong
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Colin Carlock
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Zian Liu
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Bennet D Elzey
- Department of Comparative Pathobiology, Purdue University, West Lafayette, Indiana
| | - Xiaoqi Liu
- Department of Biochemistry, Purdue University, West Lafayette, Indiana.
- Center for Cancer Research, Purdue University, West Lafayette, Indiana
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20
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Dasari S, Samy ALPA, Kajdacsy-Balla A, Bosland MC, Munirathinam G. Vitamin K2, a menaquinone present in dairy products targets castration-resistant prostate cancer cell-line by activating apoptosis signaling. Food Chem Toxicol 2018; 115:218-227. [PMID: 29432837 DOI: 10.1016/j.fct.2018.02.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 01/31/2018] [Accepted: 02/07/2018] [Indexed: 12/14/2022]
Abstract
The aim of this study was to evaluate the therapeutic effects of vitamin K2 (VK2) on castration-resistant prostate cancer (CRPC) and its anti-cancer mechanisms in a pre-clinical study using a VCaP cell line (ATCC® CRL-2876™) which was established from a vertebral bone metastasis from a patient with hormone refractory prostate cancer. Our data showed that VK2 significantly inhibited CRPC VCaP cell proliferation in a dose-dependent manner at 48 h treatment in vitro. In addition, VK2 reduced the migration potential of VCaP cells and inhibited anchorage-independent growth of these cells. Our results also showed that VK2 induces apoptosis in VCaP cells. Furthermore, VK2 enforced growth arrest in VCaP cells by activating cellular senescence. Notably, VK2 treatment elevated the levels of reactive oxygen species in VCaP cells. Western blot analysis revealed that VK2 downregulated the expression of androgen receptor, BiP, survivin, while activating caspase-3 and -7, PARP-1 cleavage, p21 and DNA damage response marker, phospho-H2AX in VCaP cells. In conclusion, our study suggests that VK2 might be a potential anti-cancer agent for CRPC by specifically targeting key anti-apoptotic, cell cycle progression and metastasis-promoting signaling molecules.
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Affiliation(s)
- Subramanyam Dasari
- Department of Biomedical Sciences, University of Illinois-College of Medicine, Rockford, IL, USA
| | | | | | - Maarten C Bosland
- Department of Pathology, University of Illinois at Chicago, Chicago, IL, USA
| | - Gnanasekar Munirathinam
- Department of Biomedical Sciences, University of Illinois-College of Medicine, Rockford, IL, USA.
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21
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Ma X, Wang L, Huang D, Li Y, Yang D, Li T, Li F, Sun L, Wei H, He K, Yu F, Zhao D, Hu L, Xing S, Liu Z, Li K, Guo J, Yang Z, Pan X, Li A, Shi Y, Wang J, Gao P, Zhang H. Polo-like kinase 1 coordinates biosynthesis during cell cycle progression by directly activating pentose phosphate pathway. Nat Commun 2017; 8:1506. [PMID: 29138396 PMCID: PMC5686148 DOI: 10.1038/s41467-017-01647-5] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 10/05/2017] [Indexed: 12/28/2022] Open
Abstract
Two hallmarks for cancer cells are the accelerated cell cycle progression as well as the altered metabolism, however, how these changes are coordinated to optimize the growth advantage for cancer cells are still poorly understood. Here we identify that Polo-like kinase 1 (Plk1), a key regulator for cell mitosis, plays a critical role for biosynthesis in cancer cells through activating pentose phosphate pathway (PPP). We find that Plk1 interacts with and directly phosphorylates glucose-6-phosphate dehydrogenase (G6PD). By activating G6PD through promoting the formation of its active dimer, Plk1 increases PPP flux and directs glucose to the synthesis of macromolecules. Importantly, we further demonstrate that Plk1-mediated activation of G6PD is critical for its role to promote cell cycle progression and cancer cell growth. Collectively, these findings establish a critical role for Plk1 in regulating biosynthesis in cancer cells, exemplifying how cell cycle progression and metabolic reprogramming are coordinated for cancer progression.
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Affiliation(s)
- Xiaoyu Ma
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Lin Wang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - De Huang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Yunyan Li
- High Magnetic Field Laboratory, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei, Anhui, 230031, China
| | - Dongdong Yang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Tingting Li
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Fudong Li
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Linchong Sun
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Haoran Wei
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Kun He
- Institute of Basic Medical Sciences, National Center of Biomedical Analysis, Beijing, 100850, China
| | - Fazhi Yu
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Debiao Zhao
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Lan Hu
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Songge Xing
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Zhaoji Liu
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Kui Li
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Jing Guo
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Zhenye Yang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Xin Pan
- Institute of Basic Medical Sciences, National Center of Biomedical Analysis, Beijing, 100850, China
| | - Ailing Li
- Institute of Basic Medical Sciences, National Center of Biomedical Analysis, Beijing, 100850, China
| | - Yunyu Shi
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Junfeng Wang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei, Anhui, 230031, China.
| | - Ping Gao
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China.
| | - Huafeng Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China.
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22
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Gong J, Kelekar G, Shen J, Shen J, Kaur S, Mita M. The expanding role of metformin in cancer: an update on antitumor mechanisms and clinical development. Target Oncol 2017; 11:447-67. [PMID: 26864078 DOI: 10.1007/s11523-016-0423-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Metformin has been used for nearly a century to treat type 2 diabetes mellitus. Epidemiologic studies first identified the association between metformin and reduced risk of several cancers. The anticancer mechanisms of metformin involve both indirect or insulin-dependent pathways and direct or insulin-independent pathways. Preclinical studies have demonstrated metformin's broad anticancer activity across a spectrum of malignancies. Prospective clinical trials involving metformin in the chemoprevention and treatment of cancer now number in the hundreds. We provide an update on the anticancer mechanisms of metformin and review the results thus far available from prospective clinical trials investigating metformin's efficacy in cancer.
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Affiliation(s)
- Jun Gong
- Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Gauri Kelekar
- Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - James Shen
- Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - John Shen
- Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Sukhpreet Kaur
- Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Monica Mita
- Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA. .,Experimental Therapeutics Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd, SCCT Mezzanine MS 35, Los Angeles, CA, 90048, USA.
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23
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Li Z, Liu J, Li J, Kong Y, Sandusky G, Rao X, Liu Y, Wan J, Liu X. Polo-like kinase 1 (Plk1) overexpression enhances ionizing radiation-induced cancer formation in mice. J Biol Chem 2017; 292:17461-17472. [PMID: 28900036 PMCID: PMC5655521 DOI: 10.1074/jbc.m117.810960] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/05/2017] [Indexed: 02/04/2023] Open
Abstract
Polo-like kinase 1 (Plk1), a serine/threonine protein kinase normally expressed in mitosis, is frequently up-regulated in multiple types of human tumors regardless of the cell cycle stage. However, the causal relationship between Plk1 up-regulation and tumorigenesis is incompletely investigated. To this end, using a conditional expression system, here we generated Plk1 transgenic mouse lines to examine the role of Plk1 in tumorigenesis. Plk1 overexpression in mouse embryonic fibroblasts prepared from the transgenic mice led to aberrant mitosis followed by aneuploidy and apoptosis. Surprisingly, Plk1 overexpression had no apparent phenotypes in the mice. Given that no malignant tumor formation was observed even after a long period of Plk1 overexpression, we reasoned that additional factors are required for tumorigenesis in Plk1-overexpressing mice. Because Plk1 can directly participate in the regulation of the DNA damage response (DDR) pathway, we challenged Plk1-overexpressing mice with ionizing radiation (IR) and found that Plk1-overexpressing mice are much more sensitive to IR than their wild-type littermates. Analysis of tumor development in the Plk1-overexpressing mice indicated a marked decrease in the time required for tumor emergence after IR. At the molecular level, Plk1 overexpression led to reduced phosphorylation of the serine/threonine kinases ATM and Chk2 and of histone H2AX after IR treatment both in vivo and in vitro Furthermore, RNA-Seq analysis suggested that Plk1 elevation decreases the expression of several DDR genes. We conclude that Plk1 overexpression may contribute to tumor formation by both inducing chromosomal instability and suppressing the DDR pathway.
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MESH Headings
- Animals
- Ataxia Telangiectasia Mutated Proteins/genetics
- Ataxia Telangiectasia Mutated Proteins/metabolism
- Cell Cycle Proteins/biosynthesis
- Cell Cycle Proteins/genetics
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Checkpoint Kinase 2/genetics
- Checkpoint Kinase 2/metabolism
- DNA Damage
- Gene Expression Regulation, Enzymologic/genetics
- Gene Expression Regulation, Enzymologic/radiation effects
- Gene Expression Regulation, Neoplastic/genetics
- Gene Expression Regulation, Neoplastic/radiation effects
- Mice
- Mice, Transgenic
- Neoplasms, Radiation-Induced/enzymology
- Neoplasms, Radiation-Induced/genetics
- Neoplasms, Radiation-Induced/pathology
- Phosphorylation/genetics
- Phosphorylation/radiation effects
- Protein Serine-Threonine Kinases/biosynthesis
- Protein Serine-Threonine Kinases/genetics
- Proto-Oncogene Proteins/biosynthesis
- Proto-Oncogene Proteins/genetics
- Radiation, Ionizing
- Polo-Like Kinase 1
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Affiliation(s)
- Zhiguo Li
- From the Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907
| | - Jinghui Liu
- From the Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907
| | - Jie Li
- From the Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907
| | - Yifan Kong
- From the Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907
| | - George Sandusky
- the Department of Pathology and Laboratory Medicine, Indiana University, Indianapolis, Indiana 46202, and
| | - Xi Rao
- the Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Yunlong Liu
- the Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Jun Wan
- the Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Xiaoqi Liu
- From the Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907,
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24
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Zingales V, Distefano A, Raffaele M, Zanghi A, Barbagallo I, Vanella L. Metformin: A Bridge between Diabetes and Prostate Cancer. Front Oncol 2017; 7:243. [PMID: 29075616 PMCID: PMC5641539 DOI: 10.3389/fonc.2017.00243] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 09/25/2017] [Indexed: 12/12/2022] Open
Abstract
Prostate cancer (PCa) has become the most frequent type of cancer in men. Recent data suggest that diabetic patients taking metformin have a lower incidence of certain cancer, including PCa. Metformin is the most common drug used in type II diabetes mellitus; its use has been shown to lower the incidence of several cancers, although there are ambiguous data about the anticancer activity of metformin. A large number of studies examined the potential antineoplastic mechanism of metformin although it is not still completely understood. This review summarizes the literature concerning the effects of metformin on PCa cells, highlighting its numerous mechanisms of action through which it can act. We analyze the possible causes of the discordances regarding the impact of metformin on risk of PCa; we discuss the latest findings in this field, suggesting that metformin may have a future role in the management of PCa both as monotherapy and in combination with other drugs.
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Affiliation(s)
- Veronica Zingales
- Department of Drug Science, Biochemistry Section, University of Catania, Catania, Italy
| | - Alfio Distefano
- Department of Drug Science, Biochemistry Section, University of Catania, Catania, Italy
| | - Marco Raffaele
- Department of Drug Science, Biochemistry Section, University of Catania, Catania, Italy
| | - Antonio Zanghi
- Department of Surgery, Azienda Ospedaliero Universitaria Policlinico Vittorio Emanuele, Catania, Italy
| | - Ignazio Barbagallo
- Department of Drug Science, Biochemistry Section, University of Catania, Catania, Italy
| | - Luca Vanella
- Department of Drug Science, Biochemistry Section, University of Catania, Catania, Italy
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25
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Ikhlas S, Ahmad M. Metformin: Insights into its anticancer potential with special reference to AMPK dependent and independent pathways. Life Sci 2017; 185:53-62. [DOI: 10.1016/j.lfs.2017.07.029] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 07/15/2017] [Accepted: 07/26/2017] [Indexed: 12/19/2022]
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26
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Kumar S, Sharma G, Chakraborty C, Sharma AR, Kim J. Regulatory functional territory of PLK-1 and their substrates beyond mitosis. Oncotarget 2017; 8:37942-37962. [PMID: 28415805 PMCID: PMC5514964 DOI: 10.18632/oncotarget.16290] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 03/03/2017] [Indexed: 12/04/2022] Open
Abstract
Polo-like kinase 1 (PLK-1) is a well-known (Ser/Thr) mitotic protein kinase and is considered as a proto-oncogene. As hyper-activation of PLK-1 is broadly associated with poor prognosis and cancer progression, it is one of the most extensively studied mitotic kinases. During mitosis, PLK-1 regulates various cell cycle events, such as spindle pole maturation, chromosome segregation and cytokinesis. However, studies have demonstrated that the role of PLK-1 is not only restricted to mitosis, but PLK-1 can also regulate other vital events beyond mitosis, including transcription, translation, ciliogenesis, checkpoint adaptation and recovery, apoptosis, chromosomes dynamics etc. Recent reviews have tried to define the regulatory role of PLK-1 during mitosis progression and tumorigenesis, but its' functional role beyond mitosis is still largely unexplored. PLK-1 can regulate the activity of many proteins that work outside of its conventional territory. The dysregulation of these proteins can cause diseases such as Alzheimer's disease, tumorigenesis etc. and may also lead to drug resistance. Thus, in this review, we discussed the versatile role of PLK-1 and tried to collect data to validate its' functional role in cell cycle regulation apart from mitosis.
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Affiliation(s)
- Shiv Kumar
- Department of Biochemistry, Institute of Cell Differentiation and Aging, Hallym University, College of Medicine, Chucheonsi, Gangwondo, Republic of Korea
| | - Garima Sharma
- Institute For Skeletal Aging & Orthopedic Surgery, Hallym University, College of Medicine, Chucheonsi, Gangwondo, Republic of Korea
| | - Chiranjib Chakraborty
- Department of Bio-informatics, School of Computer and Information Sciences, Galgotias University, Greater Noida, Uttar Pradesh, India
| | - Ashish Ranjan Sharma
- Institute For Skeletal Aging & Orthopedic Surgery, Hallym University, College of Medicine, Chucheonsi, Gangwondo, Republic of Korea
| | - Jaebong Kim
- Department of Biochemistry, Institute of Cell Differentiation and Aging, Hallym University, College of Medicine, Chucheonsi, Gangwondo, Republic of Korea
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27
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Li J, Wang R, Kong Y, Broman MM, Carlock C, Chen L, Li Z, Farah E, Ratliff TL, Liu X. Targeting Plk1 to Enhance Efficacy of Olaparib in Castration-Resistant Prostate Cancer. Mol Cancer Ther 2017; 16:469-479. [PMID: 28069876 PMCID: PMC5337144 DOI: 10.1158/1535-7163.mct-16-0361] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 12/01/2016] [Accepted: 12/22/2016] [Indexed: 02/02/2023]
Abstract
Olaparib is an FDA-approved PARP inhibitor (PARPi) that has shown promise as a synthetic lethal treatment approach for BRCA-mutant castration-resistant prostate cancer (CRPC) in clinical use. However, emerging data have also shown that even BRCA-mutant cells may be resistant to PARPi. The mechanistic basis for these drug resistances is poorly understood. Polo-like kinase 1 (Plk1), a critical regulator of many cell-cycle events, is significantly elevated upon castration of mice carrying xenograft prostate tumors. Herein, by combination with Plk1 inhibitor BI2536, we show a robust sensitization of olaparib in 22RV1, a BRCA1-deficient CRPC cell line, as well as in CRPC xenograft tumors. Mechanistically, monotherapy with olaparib results in an override of the G1-S checkpoint, leading to high expression of Plk1, which attenuates olaparib's overall efficacy. In BRCA1 wild-type C4-2 cells, Plk1 inhibition also significantly increases the efficacy of olaparib in the presence of p53 inhibitor. Collectively, our findings not only implicate the critical role of Plk1 in PARPi resistance in BRCA-mutant CRPC cells, but also shed new light on the treatment of non-BRCA-mutant patient subgroups who might also respond favorably to PARPi. Mol Cancer Ther; 16(3); 469-79. ©2017 AACR.
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Affiliation(s)
- Jie Li
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Ruixin Wang
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Yifan Kong
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Meaghan M Broman
- Center for Cancer Research, Purdue University, West Lafayette, Indiana
| | - Colin Carlock
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Long Chen
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Zhiguo Li
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Elia Farah
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Timothy L Ratliff
- Center for Cancer Research, Purdue University, West Lafayette, Indiana
| | - Xiaoqi Liu
- Department of Biochemistry, Purdue University, West Lafayette, Indiana.
- Center for Cancer Research, Purdue University, West Lafayette, Indiana
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28
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Hankinson SJ, Fam M, Patel NN. A review for clinicians: Prostate cancer and the antineoplastic properties of metformin. Urol Oncol 2016; 35:21-29. [PMID: 27836248 DOI: 10.1016/j.urolonc.2016.10.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 08/11/2016] [Accepted: 10/07/2016] [Indexed: 01/05/2023]
Abstract
OBJECTIVES Metformin has numerous antineoplastic effects including an AMP-activated protein kinase-dependent mechanism, AMP-activated protein kinase-independent mechanisms, alteration of insulin and insulin-like growth factor signaling pathways, and suppression of androgen signaling pathways that trigger prostate cancer growth and proliferation. In contrast to other malignancies that are associated with increased incidence among patients with obesity and type II diabetes mellitus (T2DM), epidemiological studies suggest that obesity and T2DM may impart a protective effect on prostate cancer incidence by creating a set of metabolic conditions that lower androgen levels. METHODS AND MATERIALS The PubMed and Web of Science databases were searched using the terms "prostate cancer," "metformin," "antineoplastic," "antitumorigenic," and "diabetes" up to the first week of August 2016. Articles regarding metformin's antineoplastic properties on prostate cancer were reviewed. RESULTS Treating T2DM with metformin may reverse the metabolic conditions that suppress androgen levels, thereby enabling higher levels of androgens to stimulate prostate growth, proliferation, and tumorigenesis. Thus, the antineoplastic properties of metformin may not be appreciable in the early stages of prostate cancer development because metformin corrects for the metabolic conditions of T2DM that impart a protective effect on prostate cancer. These findings, although inconclusive, do not support the use of metformin as a preventive agent for prostate cancer. However, the future appears bright for metformin as either a monotherapy or an adjunct to androgen deprivation therapy, external-beam radiation therapy, prostatectomy, or chemotherapy. Support for this includes meta-analyses that suggest a mortality benefit to patients with prostate cancer on metformin, a clinical trial that demonstrates metformin leads to significant improvement in metabolic syndrome parameters for patients with prostate cancer on androgen deprivation therapy, and a clinical trial that shows metformin has modest activity in the treatment of some patients with asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer. CONCLUSIONS This review summarizes the literature regarding the antineoplastic mechanisms, clinical implications, and future trajectory of clinical research for metformin in prostate cancer.
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Affiliation(s)
| | - Mina Fam
- Department of Urology, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Nitin N Patel
- Division of Urology, Department of Surgery, Rutgers New Jersey Medical School, Newark, NJ
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29
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Chen L, Li J, Farah E, Sarkar S, Ahmad N, Gupta S, Larner J, Liu X. Cotargeting HSP90 and Its Client Proteins for Treatment of Prostate Cancer. Mol Cancer Ther 2016; 15:2107-18. [PMID: 27390342 PMCID: PMC5010925 DOI: 10.1158/1535-7163.mct-16-0241] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 06/26/2016] [Indexed: 11/16/2022]
Abstract
Castration-resistant prostate cancer (CRPC) is the later stage of prostate cancer when the disease has stopped responding to androgen deprivation therapy (ADT). It has been established that androgen receptor (AR) reactivation is responsible for the recurrence of prostate cancer after ADT. Thus, targeting different pathways that regulate AR stability and activity should be a promising strategy for treatment of CRPC. Heat shock proteins (HSP) are chaperones that modify stability and activity of their client proteins. HSP90, a major player in the HSP family, regulates stability of many proteins, including AR and Polo-like kinase 1 (Plk1), a critical regulator of many cell-cycle events. Further, HSP90 is overexpressed in different cancers, including prostate cancer. Herein, we show that cotreatment of prostate cancer with AR antagonist enzalutamide and HSP90 inhibitor leads to more severe cell death due to a synergistic reduction of AR protein. Interestingly, we show that overexpression of Plk1 rescued the synergistic effect and that cotargeting HSP90 and Plk1 also leads to more severe cell death. Mechanistically, we show that E3 ligase CHIP, in addition to targeting AR, is responsible for the degradation of Plk1 as well. These findings suggest that cotargeting HSP90 and some of its client proteins may be a useful strategy in treatment of CRPC. Mol Cancer Ther; 15(9); 2107-18. ©2016 AACR.
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Affiliation(s)
- Long Chen
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Jie Li
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Elia Farah
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Sukumar Sarkar
- Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia
| | - Nihal Ahmad
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin
| | - Sanjay Gupta
- Department of Urology, Case Western Reserve University, Cleveland, Ohio
| | - James Larner
- Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia
| | - Xiaoqi Liu
- Department of Biochemistry, Purdue University, West Lafayette, Indiana. Center for Cancer Research, Purdue University, West Lafayette, Indiana.
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30
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Gutteridge REA, Ndiaye MA, Liu X, Ahmad N. Plk1 Inhibitors in Cancer Therapy: From Laboratory to Clinics. Mol Cancer Ther 2016; 15:1427-35. [PMID: 27330107 PMCID: PMC4936921 DOI: 10.1158/1535-7163.mct-15-0897] [Citation(s) in RCA: 269] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 04/06/2016] [Indexed: 01/06/2023]
Abstract
Polo-like kinase 1 (Plk1) overexpression has been shown to occur in a wide range of tumors, prompting research and development of Plk1 inhibitors as a means of cancer treatment. This review discusses recent advances in the development of Plk1 inhibitors for cancer management. Plk1 inhibition has been shown to cause mitotic block and apoptosis of cells with higher mitotic index and therefore higher Plk1 expression. The potential of Plk1 inhibitors as cancer therapeutics has been widely investigated. However, a complete understanding of Plk1 biology/mechanism is yet to be fully achieved. Resistance to certain chemotherapeutic drugs has been linked to Plk1 overexpression, and Plk1-mediated mitotic events such as microtubule rearrangement have been found to reduce the efficacy of chemotherapeutic agents. The Plk1 inhibitor volasertib has shown considerable promise in clinical studies, having reached phase III trials. However, preclinical success with Plk1 inhibitors has not translated well into clinical success. In our view, combined therapies targeting other relevant pathways together with Plk1 may be vital to combat issues observed with monotherapy, especially resistance. In addition, research should also be directed toward understanding the mechanisms of Plk1 and designing additional next generations of specific, potent Plk1 inhibitors to target cancer. Mol Cancer Ther; 15(7); 1427-35. ©2016 AACR.
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Affiliation(s)
| | - Mary Ann Ndiaye
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin
| | - Xiaoqi Liu
- Department of Biochemistry, Purdue University, West Lafayette, Indiana
| | - Nihal Ahmad
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin. William S. Middleton Memorial VA Hospital, Madison, Wisconsin.
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31
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Pennanen P, Syvälä H, Bläuer M, Savinainen K, Ylikomi T, Tammela TLJ, Murtola TJ. The effects of metformin and simvastatin on the growth of LNCaP and RWPE-1 prostate epithelial cell lines. Eur J Pharmacol 2016; 788:160-167. [PMID: 27341997 DOI: 10.1016/j.ejphar.2016.06.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 06/13/2016] [Accepted: 06/21/2016] [Indexed: 10/21/2022]
Abstract
The anti-diabetic drug metformin and cholesterol-lowering statins inhibit prostate cancer cell growth in vitro and have been linked with lowered risk of prostate cancer in epidemiological studies. We evaluated the effects of these drugs on cancerous and non-cancerous prostate epithelial cell lines. Cancer (LNCaP) and normal (RWPE-1) prostate epithelial cell lines were treated with pharmacologic concentrations of metformin and simvastatin alone and in combinations. Relative changes in cell number were measured with crystal violet staining method. Drug effects on apoptosis and cell cycle were measured with flow cytometry. We also measured changes in the activation and expression of a set of reported target proteins of metformin and statins with Western blotting. Metformin decreased the relative cell number of LNCaP cells by inducing G1 cell cycle block, autophagy and apoptosis, and slightly increased cytosolic ATP levels, whereas RWPE-1 cells were resistant to metformin. However, RWPE-1 cells were sensitive to simvastatin, which induced G2 cell cycle block, autophagy and apoptosis, and increased cytosolic ATP levels in these cells. Combination of metformin and simvastatin synergistically decreased cytosolic ATP levels, increased autophagy and instead of apoptosis, induced necrosis in LNCaP cells. Synergistic effects were not observed in RWPE-1 cells. These results suggest, that prostate cancer cells may be more vulnerable to combined growth-inhibiting effects of metformin and simvastatin compared to normal cells. The data presented here provide evidence for the potency of combined metformin and statin, also at pharmacologic concentrations, as a chemotherapeutic option for prostate cancer.
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Affiliation(s)
- Pasi Pennanen
- University of Tampere, School of Medicine, Tampere, Finland.
| | - Heimo Syvälä
- University of Tampere, School of Medicine, Department of Anatomy, Tampere, Finland
| | - Merja Bläuer
- Tampere University Hospital, Department of Gastroenterology and Alimentary Tract Surgery and Tampere Pancreas Laboratory, Tampere, Finland
| | | | - Timo Ylikomi
- University of Tampere School of Medicine, Department of Cell Biology, Tampere, Finland
| | - Teuvo L J Tammela
- University of Tampere, School of Medicine, Tampere, Finland; Tampere University Hospital, Department of Urology, Tampere, Finland
| | - Teemu J Murtola
- University of Tampere, School of Medicine, Tampere, Finland; Tampere University Hospital, Department of Urology, Tampere, Finland
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32
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Cristóbal I, Rojo F, Madoz-Gúrpide J, García-Foncillas J. Cross Talk between Wnt/β-Catenin and CIP2A/Plk1 Signaling in Prostate Cancer: Promising Therapeutic Implications. Mol Cell Biol 2016; 36:1734-9. [PMID: 27090640 PMCID: PMC4907099 DOI: 10.1128/mcb.00130-16] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Aberrant activation of the Wnt/β-catenin pathway and polo-like kinase 1 (Plk1) overexpression represent two common events in prostate cancer with relevant functional implications. This minireview analyzes their potential therapeutic significance in prostate cancer based on their role as androgen receptor (AR) signaling regulators and the pivotal role of the tumor suppressor protein phosphatase 2A (PP2A) modulating these pathways.
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Affiliation(s)
- Ion Cristóbal
- Translational Oncology Division, Oncohealth Institute, IIS Fundación Jiménez Diaz, UAM, University Hospital Fundación Jiménez Diaz, Madrid, Spain
| | - Federico Rojo
- Pathology Department, IIS Fundación Jiménez Diaz, UAM, Madrid, Spain
| | | | - Jesús García-Foncillas
- Translational Oncology Division, Oncohealth Institute, IIS Fundación Jiménez Diaz, UAM, University Hospital Fundación Jiménez Diaz, Madrid, Spain
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33
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Li J, Wang R, Schweickert PG, Karki A, Yang Y, Kong Y, Ahmad N, Konieczny SF, Liu X. Plk1 inhibition enhances the efficacy of gemcitabine in human pancreatic cancer. Cell Cycle 2016; 15:711-9. [PMID: 26890815 PMCID: PMC4845940 DOI: 10.1080/15384101.2016.1148838] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 01/19/2016] [Accepted: 01/20/2016] [Indexed: 01/21/2023] Open
Abstract
Gemcitabine is the standard-of-care for chemotherapy in patients with pancreatic adenocarcinoma and it can directly incorporate into DNA or inhibit ribonucleotide reductase to prevent DNA replication and, thus, tumor cell growth. Most pancreatic tumors, however, develop resistance to gemcitabine. Polo-like kinase 1 (Plk1), a critical regulator in many cell cycle events, is significantly elevated in human pancreatic cancer. In this study, we show that Plk1 is required for the G1/S transition and that inhibition of Plk1 significantly reduces the DNA synthesis rate in human pancreatic cancer cells. Furthermore, the combined effect of a specific Plk1 inhibitor GSK461364A with gemcitabine was examined. We show that inhibition of Plk1 significantly potentiates the anti-neoplastic activity of gemcitabine in both cultured pancreatic cancer cells and Panc1-derived orthotopic pancreatic cancer xenograft tumors. Overall, our study demonstrates that co-targeting Plk1 can significantly enhance the efficacy of gemcitabine, offering a promising new therapeutic option for the treatment of gemcitabine-resistant human pancreatic cancer.
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Affiliation(s)
- Jie Li
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
| | - Ruixin Wang
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
| | | | - Anju Karki
- Department of Biological Science, Purdue University, West Lafayette, IN, USA
| | - Yi Yang
- Department of Biological Science, Purdue University, West Lafayette, IN, USA
| | - Yifan Kong
- Department of Biological Science, Purdue University, West Lafayette, IN, USA
| | - Nihal Ahmad
- Department of Dermatology, University of Wisconsin, Madison, WI, USA
| | - Stephen F. Konieczny
- Department of Biological Science, Purdue University, West Lafayette, IN, USA
- Center for Cancer Research, Purdue University, West Lafayette, IN, USA
| | - Xiaoqi Liu
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
- Center for Cancer Research, Purdue University, West Lafayette, IN, USA
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Chen L, Ahmad N, Liu X. Combining p53 stabilizers with metformin induces synergistic apoptosis through regulation of energy metabolism in castration-resistant prostate cancer. Cell Cycle 2016; 15:840-9. [PMID: 26900800 PMCID: PMC4845973 DOI: 10.1080/15384101.2016.1151582] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 01/22/2016] [Accepted: 02/01/2016] [Indexed: 10/22/2022] Open
Abstract
Since altered energy metabolism is a hallmark of cancer, many drugs targeting metabolic pathways are in active clinical trials. The tumor suppressor p53 is often inactivated in cancer, either through downregulation of protein or loss-of-function mutations. As such, stabilization of p53 is considered as one promising approach to treat those cancers carrying wild type (WT) p53. Herein, SIRT1 inhibitor Tenovin-1 and polo-like kinase 1 (Plk1) inhibitor BI2536 were used to stabilize p53. We found that both Tennovin-1 and BI2536 increased the anti-neoplastic activity of metformin, an inhibitor of oxidative phosphorylation, in a p53 dependent manner. Since p53 has also been shown to regulate metabolic pathways, we further analyzed glycolysis and oxidative phosphorylation upon drug treatments. We showed that both Tennovin-1 and BI2536 rescued metformin-induced glycolysis and that both Tennovin-1 and BI2536 potentiated metformin-associated inhibition of oxidative phosphorylation. Of significance, castration-resistant prostate cancer (CRPC) C4-2 cells show a much more robust response to the combination treatment than the parental androgen-dependent prostate cancer LNCaP cells, indicating that targeting energy metabolism with metformin plus p53 stabilizers might be a valid approach to treat CRPC carrying WT p53.
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Affiliation(s)
- Long Chen
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
| | - Nihal Ahmad
- Department of Dermatology, University of Wisconsin, Madison, WI, USA
| | - Xiaoqi Liu
- Department of Biochemistry, Purdue University, West Lafayette, IN, USA
- Center for Cancer Research, Purdue University, West Lafayette, IN, USA
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