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Li Y, Xing Y, Wang X, Hu B, Zhao X, Zhang H, Han F, Geng N, Wang F, Li Y, Li J, Jin F, Li F. PAK5 promotes RNA helicase DDX5 sumoylation and miRNA-10b processing in a kinase-dependent manner in breast cancer. Cell Rep 2021; 37:110127. [PMID: 34936874 DOI: 10.1016/j.celrep.2021.110127] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 09/28/2021] [Accepted: 11/23/2021] [Indexed: 01/15/2023] Open
Abstract
P21-activated kinase 5 (PAK5) plays an important role in tumors. However, the functional role of PAK5 in mammary tumorigenesis in vivo remains unclear. Here, we show that PAK5 deficiency represses MMTV-PyVT-driven breast tumorigenesis. DEAD-box RNA helicase 5 (DDX5) is a substrate of PAK5, which is phosphorylated on threonine 69. PAK5-mediated DDX5 phosphorylation promotes breast cancer cell proliferation and metastasis. The increased expression levels of PAK5 and phospho-DDX5 threonine 69 are associated with metastasis and poor clinical outcomes of patients. PAK5 facilitates the phosphorylation-dependent sumoylation of DDX5 to stabilize DDX5. Both the phosphorylation and sumoylation of DDX5 enhance the formation of a DDX5/Drosha/DGCR8 complex, thus promoting microRNA-10b processing. Finally, we verify decreased expression of DDX5 phosphorylation and sumoylation and mature miR-10b in PAK5-/-/MMTV-PyVT transgenic mice. Our findings provide insights into the function of PAK5 in microRNA (miRNA) biogenesis, which might be a potential therapeutic target for breast cancer.
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Affiliation(s)
- Yang Li
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Yao Xing
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Xu Wang
- Department of Breast Surgery, Department of Surgical Oncology, Research Unit of General Surgery, The First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning 110001, China
| | - Bingtao Hu
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Xin Zhao
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Hongyan Zhang
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Fuyi Han
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Nanxi Geng
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Fei Wang
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Yanshu Li
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Jiabin Li
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China
| | - Feng Jin
- Department of Breast Surgery, Department of Surgical Oncology, Research Unit of General Surgery, The First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning 110001, China.
| | - Feng Li
- Department of Cell Biology, Key Laboratory of Cell Biology, National Health Commission of the PRC and Key Laboratory of Medical Cell Biology, Ministry of Education of the PRC, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, China.
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Bautista L, Knippler CM, Ringel MD. p21-Activated Kinases in Thyroid Cancer. Endocrinology 2020; 161:bqaa105. [PMID: 32609833 PMCID: PMC7417880 DOI: 10.1210/endocr/bqaa105] [Citation(s) in RCA: 6] [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: 05/27/2020] [Accepted: 06/24/2020] [Indexed: 02/07/2023]
Abstract
The family of p21-activated kinases (PAKs) are oncogenic proteins that regulate critical cellular functions. PAKs play central signaling roles in the integrin/CDC42/Rho, ERK/MAPK, PI3K/AKT, NF-κB, and Wnt/β-catenin pathways, functioning both as kinases and scaffolds to regulate cell motility, mitosis and proliferation, cytoskeletal rearrangement, and other cellular activities. PAKs have been implicated in both the development and progression of a wide range of cancers, including breast cancer, pancreatic melanoma, thyroid cancer, and others. Here we will discuss the current knowledge on the structure and biological functions of both group I and group II PAKs, as well as the roles that PAKs play in oncogenesis and progression, with a focus on thyroid cancer and emerging data regarding BRAF/PAK signaling.
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Affiliation(s)
- Luis Bautista
- Division of Endocrinology, Diabetes, and Metabolism, Department of Internal Medicine, and Cancer Biology Program, The Ohio State University College of Medicine and Arthur G. James Comprehensive Cancer Center, Columbus, Ohio
| | - Christina M Knippler
- Division of Endocrinology, Diabetes, and Metabolism, Department of Internal Medicine, and Cancer Biology Program, The Ohio State University College of Medicine and Arthur G. James Comprehensive Cancer Center, Columbus, Ohio
- Department of Hematology and Medical Oncology, Emory University and Winship Cancer Institute, Atlanta, Georgia
| | - Matthew D Ringel
- Division of Endocrinology, Diabetes, and Metabolism, Department of Internal Medicine, and Cancer Biology Program, The Ohio State University College of Medicine and Arthur G. James Comprehensive Cancer Center, Columbus, Ohio
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Bao Z, Ji W, Yang Y, Chen Z, Li Z, Wang K, Lu T, Yu Y, Xia W, Lu S. PAK5 promotes the cell stemness ability by phosphorylating SOX2 in lung squamous cell carcinomas. Exp Cell Res 2020; 395:112187. [PMID: 32721391 DOI: 10.1016/j.yexcr.2020.112187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 07/15/2020] [Accepted: 07/17/2020] [Indexed: 01/01/2023]
Abstract
Growing evidences suggest that the overexpression of p21-activated kinase 5 (PAK5) plays an important role in various tumor progression. However, the role of PAK5 and its downstream target gene(s) in lung squamous cell carcinomas (LUSC) are waiting to be elucidated. TCGA data were utilized to evaluate the expression levels of PAK5 in LUSC. We then explored the role of PAK5 in maintaining the stem-like phenotype of lung squamous cancer cells through RT-PCR, flow cytometry, oncosphere-forming assay. In addition, co-immunoprecipitation, western blotting and immunofluorescence assays were used to determine SOX2 as a novel effector of PAK5. Xenograft models in nude mice were established to explore the roles of PAK5 in lung cancer growth. In this study, we have shown that PAK5 is overexpressed in LUSC tissues. The absence of PAK5 abolishes self-renewal ability of LUSC cells by decreasing the expression and phosphorylation of SOX2 in vitro and in vivo. In xenograft models, knockdown or pharmacological inhibition of PAK5 suppressed the tumor growth and metastasis of lung squamous cancer cells in vivo. Taken together, our findings suggest that the PAK5-mediated SOX2 phosphorylation promoted the cancer stem cell-like phenotype of LUSC cells. PAK5 inhibition may be a promising target in the treatment of SOX2 positive lung squamous cell cancer.
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Affiliation(s)
- Zinan Bao
- Shanghai Lung Cancer Center, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, West Huaihai Road 241, 20030, Shanghai, China; School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University, Huashan Road 1954, 200030, Shanghai, China
| | - Wenxiang Ji
- Shanghai Lung Cancer Center, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, West Huaihai Road 241, 20030, Shanghai, China
| | - Ying Yang
- Shanghai Lung Cancer Center, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, West Huaihai Road 241, 20030, Shanghai, China
| | - Zhuo Chen
- School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University, Huashan Road 1954, 200030, Shanghai, China
| | - Ziming Li
- Shanghai Lung Cancer Center, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, West Huaihai Road 241, 20030, Shanghai, China
| | - Kaixuan Wang
- Shanghai Lung Cancer Center, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, West Huaihai Road 241, 20030, Shanghai, China
| | - Tingting Lu
- Shanghai Lung Cancer Center, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, West Huaihai Road 241, 20030, Shanghai, China
| | - Yongfeng Yu
- Shanghai Lung Cancer Center, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, West Huaihai Road 241, 20030, Shanghai, China
| | - Weiliang Xia
- School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University, Huashan Road 1954, 200030, Shanghai, China.
| | - Shun Lu
- Shanghai Lung Cancer Center, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, West Huaihai Road 241, 20030, Shanghai, China.
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Huang S, Zhu Y, Wang C, Li X, Cui X, Tu S, You L, Fu J, Chen Z, Hu W, Gong W. PAK5 facilitates the proliferation, invasion and migration in colorectal cancer cells. Cancer Med 2020; 9:4777-4790. [PMID: 32383357 PMCID: PMC7333859 DOI: 10.1002/cam4.3084] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 04/08/2020] [Accepted: 04/08/2020] [Indexed: 12/18/2022] Open
Abstract
Colorectal cancer (CRC) is the third-most common cancer around the world, accounting for approximately 10% of cancer-related mortality. Deeper molecular understanding of colorectal carcinogenesis will provide evidences for identification of early diagnostic indicators and novel therapeutic strategies for CRC treatment. The p21cdc42/rac1 -activated kinase 5 (PAK5) has been reported to be involved in a variety of tumor-promoting behaviors, whereas the underlying mechanisms of PAK5 in CRC progression are still obscure. Our current study revealed an upregulated expression of PAK5 in human CRC tissues as compared with normal adjacent biopsies, which was associated with tumor progression and metastasis. We further unraveled that inhibition of PAK5 was correlated with restrained proliferation, migration, and invasion of CRC cells in vitro and in vivo. Moreover, we showed an indispensable role of PAK5 in interacting with Cdc42 and Integrin β1, β3, thus, to facilitate the migration and invasion of CRC cells. Collectively, we pointed out a potential of PAK5 to serve as a novel therapeutic target in restricting CRC proliferation and metastasis. The uncovered mechanisms will deepen the comprehension with regard to the mechanisms of CRC progression, as well as providing new insights for therapeutic intervention in colorectal cancer.
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Affiliation(s)
- Silin Huang
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
| | - Ying Zhu
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
| | - Chunfei Wang
- Endoscopy CenterThe Seventh Affiliated Hospital of Sun Yat‐Sen UniversityShenzhenGuangdongChina
| | - Xiaxi Li
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
| | - Xiaobing Cui
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
| | - Sufang Tu
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
| | - Lijuan You
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
| | - JingWen Fu
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
| | - Zemin Chen
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
| | - Wei Hu
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
- Department of Anaesthesia and Intensive CareThe Chinese University of Hong KongHong Kong
| | - Wei Gong
- Department of GastroenterologyShenzhen HospitalSouthern Medical UniversityShenzhenGuangdongChina
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Phosphorylation-dependent activity-based conformational changes in P21-activated kinase family members and screening of novel ATP competitive inhibitors. PLoS One 2019; 14:e0225132. [PMID: 31738805 PMCID: PMC6860928 DOI: 10.1371/journal.pone.0225132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 10/29/2019] [Indexed: 12/04/2022] Open
Abstract
P21-activated kinases (PAKs) are serine/threonine protein kinases that are subdivided into two groups on the basis of their domain architecture: group-I (PAK1–3) and group-II (PAK4–6). PAKs are considered as attractive drug targets that play vital role in cell proliferation, survival, motility, angiogenesis and cytoskeletal dynamics. In current study, molecular dynamics simulation-based comparative residual contributions and differential transitions were monitored in both active and inactive states of human PAK homologs for therapeutic intervention. Due to their involvement in cancer, infectious diseases, and neurological disorders, it is inevitable to develop novel therapeutic strategies that specifically target PAKs on the basis of their activity pattern. In order to isolate novel inhibitors that are able to bind at the active sites of PAK1 and PAK4, high throughput structure-based virtual screening was performed. Multiple lead compounds were proposed on the basis of their binding potential and targeting region either phosphorylated (active) or unphosphorylated PAK isoform (inactive). Thus, ATP-competitive inhibitors may prove ideal therapeutic choice against PAK family members. The detailed conformational readjustements occurring in the PAKs upon phosphorylation-dephosphorylation events may serve as starting point for devising novel drug molecules that are able to target on activity basis. Overall, the observations of current study may add valuable contribution in the inventory of novel inhibitors that may serve as attractive lead compounds for targeting PAK family members on the basis of activity-based conformational changes.
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Huo FC, Pan YJ, Li TT, Mou J, Pei DS. PAK5 promotes the migration and invasion of cervical cancer cells by phosphorylating SATB1. Cell Death Differ 2018; 26:994-1006. [PMID: 30082769 DOI: 10.1038/s41418-018-0178-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 07/08/2018] [Accepted: 07/16/2018] [Indexed: 02/07/2023] Open
Abstract
p21-activated kinase 5 (PAK5) is involved in several oncogenic signaling pathways and its amplification or overexpression has been found in various types of cancer; however, the pathophysiologic role of PAK5 in cervical cancer (CC) remains elusive. This study aims to elucidate the effects of PAK5 on CC metastasis and its specific regulation mechanism. We performed western blotting and immunohistochemistry (IHC) analysis and found that the expression levels of PAK5 were significantly upregulated in CC cells and tissues. In addition, statistical analysis via IHC showed that increased PAK5 significantly correlated with CC progression. Mn2+-Phos-tag SDS-PAGE, western blotting, immunofluorescence and dual luciferase reporter assays were utilized to determine the involvement of SATB1 in PAK5-mediated epithelial-mesenchymal transition (EMT). We found that PAK5-mediated special AT-rich binding protein-1 (SATB1) phosphorylation on Ser47 initiated EMT cascade and promoted migration and invasion of CC cells. Furthermore, overexpression of PAK5 induced lung metastasis of CC cells in xenograft modes. Taken together, we conclude that PAK5 is a novel prognostic indicator and plays an important role in the CC metastasis.
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Affiliation(s)
- Fu-Chun Huo
- Department of pathology, Xuzhou Medical University, Xuzhou, 221004, China.,Jiangsu Key Laboratory of Biological Cancer Therapy, Xuzhou Medical University, Xuzhou, 221002, China
| | - Yao-Jie Pan
- Department of Oncology, The Affiliated Yancheng Hospital of Medicine School of Southeast University, Yancheng, 224001, China
| | - Tong-Tong Li
- Department of pathology, Xuzhou Medical University, Xuzhou, 221004, China
| | - Jie Mou
- School of Pharmacy, Xuzhou Medical University, Xuzhou, 221004, China.
| | - Dong-Sheng Pei
- Department of pathology, Xuzhou Medical University, Xuzhou, 221004, China. .,Jiangsu Key Laboratory of Biological Cancer Therapy, Xuzhou Medical University, Xuzhou, 221002, China.
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P21-Activated Kinase Inhibitors FRAX486 and IPA3: Inhibition of Prostate Stromal Cell Growth and Effects on Smooth Muscle Contraction in the Human Prostate. PLoS One 2016; 11:e0153312. [PMID: 27071060 PMCID: PMC4829229 DOI: 10.1371/journal.pone.0153312] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 03/28/2016] [Indexed: 12/25/2022] Open
Abstract
Prostate smooth muscle tone and hyperplastic growth are involved in the pathophysiology and treatment of male lower urinary tract symptoms (LUTS). Available drugs are characterized by limited efficacy. Patients' adherence is particularly low to combination therapies of 5α-reductase inhibitors and α1-adrenoceptor antagonists, which are supposed to target contraction and growth simultaneously. Consequently, molecular etiology of benign prostatic hyperplasia (BPH) and new compounds interfering with smooth muscle contraction or growth in the prostate are of high interest. Here, we studied effects of p21-activated kinase (PAK) inhibitors (FRAX486, IPA3) in hyperplastic human prostate tissues, and in stromal cells (WPMY-1). In hyperplastic prostate tissues, PAK1, -2, -4, and -6 may be constitutively expressed in catecholaminergic neurons, while PAK1 was detected in smooth muscle and WPMY-1 cells. Neurogenic contractions of prostate strips by electric field stimulation were significantly inhibited by high concentrations of FRAX486 (30 μM) or IPA3 (300 μM), while noradrenaline- and phenylephrine-induced contractions were not affected. FRAX486 (30 μM) inhibited endothelin-1- and -2-induced contractions. In WPMY-1 cells, FRAX486 or IPA3 (24 h) induced concentration-dependent (1-10 μM) degeneration of actin filaments. This was paralleled by attenuation of proliferation rate, being observed from 1 to 10 μM FRAX486 or IPA3. Cytotoxicity of FRAX486 and IPA3 in WPMY-1 cells was time- and concentration-dependent. Stimulation of WPMY-1 cells with endothelin-1 or dihydrotestosterone, but not noradrenaline induced PAK phosphorylation, indicating PAK activation by endothelin-1. Thus, PAK inhibitors may inhibit neurogenic and endothelin-induced smooth muscle contractions in the hyperplastic human prostate, and growth of stromal cells. Targeting prostate smooth muscle contraction and stromal growth at once by a single compound is principally possible, at least under experimental conditions.
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p21-Activated kinase 5 affects cisplatin-induced apoptosis and proliferation in hepatocellular carcinoma cells. Tumour Biol 2015; 36:3685-91. [PMID: 25560489 DOI: 10.1007/s13277-014-3007-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 12/23/2014] [Indexed: 12/29/2022] Open
Abstract
p21-Activated kinase 5 (PAK5) is the last identified member of the PAK family. The PAKs are highly conserved serine/threonine and effector proteins for Cdc42 and Rac and are essential in regulating cell motility and survival. Previous studies have demonstrated that PAK5 played a pivotal role in apoptosis, proliferation, cancer migration, and invasion. However, the biological function of PAK5 in hepatocellular carcinoma, as well as its underlying mechanism, still remains to be fully elucidated. In the present study, we demonstrated that PAK5 markedly inhibited cisplatin-induced apoptosis and promoted cell proliferation in hepatocellular carcinoma cells. Moreover, our results showed that overexpression of PAK5 contributed to cell cycle regulation. In order to elucidate the underlying mechanism of PAK5 on cisplatin-induced apoptosis and cell cycle regulation, we also examined the protein expressions of chk2 and p-chk2. In summary, our study investigated the role of PAK5 in cisplatin-induced cellular processes and provided evidence of its underlying mechanism.
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Abstract
INTRODUCTION Overexpression of p21-activated kinase 5 (PAK5) is discovered in many tumors, probably due to its regulation in cytoskeleton, antiapoptosis and proliferation. A better understanding of the modulation mechanisms of PAK5 is needed for the development of tumor treatment where current therapeutics is inadequate. AREAS COVERED This review discusses the current understanding of PAK5 functions as an oncogenic kinase in tumor cellular regulation. Mechanisms of action and molecular pathways involved in cytoskeleton regulation, antiapoptosis and proliferation of tumors are discussed. EXPERT OPINION PAKs are serine/threonine kinases and downstream effectors for Cdc42 and Rac, the subfamilies of Rho small GTPases. PAK5 shares sequence identities in p21-GTPase-binding domain and kinase domain and is completely different in other regions compared with other PAKs. Overexpression of PAK5 has been found in several tumors, probably due to its contribution to proliferation, cytoskeleton and anti-apoptosis. Additional regulation mechanisms which are independent of Rho GTPases also indicate that PAK5 functions as a special signal molecule in cellular signaling pathways of tumor progression.
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Affiliation(s)
- Yi-Yang Wen
- Jiangsu Key Laboratory of Biological Cancer Therapy, Xuzhou Medical College , 84 West Huai-hai Road, Xuzhou, Jiangsu , China +86 0516 85582513 ; ;
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