1
|
Aquino A, Bianchi N, Terrazzan A, Franzese O. Protein Kinase C at the Crossroad of Mutations, Cancer, Targeted Therapy and Immune Response. BIOLOGY 2023; 12:1047. [PMID: 37626933 PMCID: PMC10451643 DOI: 10.3390/biology12081047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/18/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023]
Abstract
The frequent PKC dysregulations observed in many tumors have made these enzymes natural targets for anticancer applications. Nevertheless, this considerable interest in the development of PKC modulators has not led to the expected therapeutic benefits, likely due to the complex biological activities regulated by PKC isoenzymes, often playing ambiguous and protective functions, further driven by the occurrence of mutations. The structure, regulation and functions of PKCs have been extensively covered in other publications. Herein, we focused on PKC alterations mostly associated with complete functional loss. We also addressed the modest yet encouraging results obtained targeting PKC in selected malignancies and the more frequent negative clinical outcomes. The reported observations advocate the need for more selective molecules and a better understanding of the involved pathways. Furthermore, we underlined the most relevant immune mechanisms controlled by PKC isoforms potentially impacting the immune checkpoint inhibitor blockade-mediated immune recovery. We believe that a comprehensive examination of the molecular features of the tumor microenvironment might improve clinical outcomes by tailoring PKC modulation. This approach can be further supported by the identification of potential response biomarkers, which may indicate patients who may benefit from the manipulation of distinctive PKC isoforms.
Collapse
Affiliation(s)
- Angelo Aquino
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy;
| | - Nicoletta Bianchi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (N.B.); (A.T.)
| | - Anna Terrazzan
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (N.B.); (A.T.)
- Laboratory for Advanced Therapy Technologies (LTTA), University of Ferrara, 44121 Ferrara, Italy
| | - Ornella Franzese
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy;
| |
Collapse
|
2
|
Black JD, Affandi T, Black AR, Reyland ME. PKCα and PKCδ: Friends and Rivals. J Biol Chem 2022; 298:102194. [PMID: 35760100 PMCID: PMC9352922 DOI: 10.1016/j.jbc.2022.102194] [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: 03/10/2022] [Revised: 06/13/2022] [Accepted: 06/21/2022] [Indexed: 01/06/2023] Open
Abstract
PKC comprises a large family of serine/threonine kinases that share a requirement for allosteric activation by lipids. While PKC isoforms have significant homology, functional divergence is evident among subfamilies and between individual PKC isoforms within a subfamily. Here, we highlight these differences by comparing the regulation and function of representative PKC isoforms from the conventional (PKCα) and novel (PKCδ) subfamilies. We discuss how unique structural features of PKCα and PKCδ underlie differences in activation and highlight the similar, divergent, and even opposing biological functions of these kinases. We also consider how PKCα and PKCδ can contribute to pathophysiological conditions and discuss challenges to targeting these kinases therapeutically.
Collapse
Affiliation(s)
- Jennifer D Black
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE.
| | - Trisiani Affandi
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus
| | - Adrian R Black
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE
| | - Mary E Reyland
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus.
| |
Collapse
|
3
|
Zhao H, Ma J, Zuo X, Li F. Electrochemical Analysis for Multiscale Single Entities on the Confined Interface
†. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202000722] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Haipei Zhao
- School of Chemistry and Chemical Engineering, and Institute of Translational Medicine Shanghai Jiao Tong University Shanghai 200240 China
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, School of Medicine Shanghai Jiao Tong University Shanghai 200127 China
| | - Jinliang Ma
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, School of Medicine Shanghai Jiao Tong University Shanghai 200127 China
| | - Xiaolei Zuo
- School of Chemistry and Chemical Engineering, and Institute of Translational Medicine Shanghai Jiao Tong University Shanghai 200240 China
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, School of Medicine Shanghai Jiao Tong University Shanghai 200127 China
| | - Fan Li
- Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, School of Medicine Shanghai Jiao Tong University Shanghai 200127 China
| |
Collapse
|
4
|
Black AR, Black JD. The complexities of PKCα signaling in cancer. Adv Biol Regul 2021; 80:100769. [PMID: 33307285 PMCID: PMC8141086 DOI: 10.1016/j.jbior.2020.100769] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 11/15/2020] [Indexed: 01/06/2023]
Abstract
Protein kinase C α (PKCα) is a ubiquitously expressed member of the PKC family of serine/threonine kinases with diverse functions in normal and neoplastic cells. Early studies identified anti-proliferative and differentiation-inducing functions for PKCα in some normal tissues (e.g., regenerating epithelia) and pro-proliferative effects in others (e.g., cells of the hematopoietic system, smooth muscle cells). Additional well documented roles of PKCα signaling in normal cells include regulation of the cytoskeleton, cell adhesion, and cell migration, and PKCα can function as a survival factor in many contexts. While a majority of tumors lose expression of PKCα, others display aberrant overexpression of the enzyme. Cancer-related mutations in PKCα are uncommon, but rare examples of driver mutations have been detected in certain cancer types (e. g., choroid gliomas). Here we review the role of PKCα in various cancers, describe mechanisms by which PKCα affects cancer-related cell functions, and discuss how the diverse functions of PKCα contribute to tumor suppressive and tumor promoting activities of the enzyme. We end the discussion by addressing mutations and expression of PKCα in tumors and the clinical relevance of these findings.
Collapse
Affiliation(s)
- Adrian R Black
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Jennifer D Black
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
| |
Collapse
|
5
|
Zhou Q, Su Z, Li Y, Liu Y, Wang L, Lu S, Wang S, Gan T, Liu F, Zhou X, Wei M, Liu G, Chen S. Genome-Wide Association Mapping and Gene Expression Analyses Reveal Genetic Mechanisms of Disease Resistance Variations in Cynoglossus semilaevis. Front Genet 2019; 10:1167. [PMID: 31824570 PMCID: PMC6880758 DOI: 10.3389/fgene.2019.01167] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 10/23/2019] [Indexed: 12/15/2022] Open
Abstract
The sustainable development of aquaculture has been impeded by infectious diseases worldwide. However, the genomic architecture and the genetic basis underlying the disease resistance remain poorly understood, which severely hampers both the understanding of the evolution of fish disease resistance traits and the prevention of these diseases in the aquaculture community. Cynoglossus semilaevis is a representative and commercially-important flatfish species. Here we combined genome-wide association study and Fst and nucleotide diversity filtration to identify loci important for the disease resistance. Based on 1,016,774 single-nucleotide polymorphisms (SNPs) identified from 650 Gb genome resequencing data of 505 individuals, we detected 33 SNPs significantly associated with disease resistance and 79 candidate regions after filtration steps. Both the allele frequencies and genotype frequencies of the associated loci were significantly different between the resistant and susceptible fish, suggesting a role in the genetic basis of disease resistance. The SNP with strongest association with disease resistance was located in Chr 17, at 145 bp upstream of fblx19 gene, and overlapped with the major quantitative trait locus previously identified. Several genes, such as plekha7, nucb2, and fgfr2, were also identified to potentially play roles in the disease resistance. Furthermore, the expression of some associating genes were likely under epigenetic regulations between the bacterial resistant and susceptible families. These results provide insights into the mechanism that enable variation of disease resistance to bacterial pathogen infection. The identified polymorphisms and genes are valuable targets and molecular resources for disease resistance and other traits, and for advanced breeding practice for superior germplasm in fish aquaculture.
Collapse
Affiliation(s)
- Qian Zhou
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China.,Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.,Key Laboratory for Marine Fishery Biotechnology and Genetic Breeding, Qingdao, China
| | - Zhencheng Su
- Novogene Bioinformatics Technology Co., Ltd, Beijing, China
| | - Yangzhen Li
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China
| | - Yang Liu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China
| | - Lei Wang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China
| | - Sheng Lu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China
| | - Shuanyan Wang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China
| | - Tian Gan
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China
| | - Feng Liu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China
| | - Xun Zhou
- Novogene Bioinformatics Technology Co., Ltd, Beijing, China
| | - Min Wei
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China
| | - Guangjian Liu
- Novogene Bioinformatics Technology Co., Ltd, Beijing, China
| | - Songlin Chen
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China.,Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.,Key Laboratory for Marine Fishery Biotechnology and Genetic Breeding, Qingdao, China
| |
Collapse
|
6
|
Cheng Y, Zhu Y, Xu W, Xu J, Yang M, Chen P, Zhao J, Geng L, Gong S. PKCα in colon cancer cells promotes M1 macrophage polarization via MKK3/6-P38 MAPK pathway. Mol Carcinog 2018; 57:1017-1029. [PMID: 29637628 DOI: 10.1002/mc.22822] [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: 10/22/2017] [Revised: 03/17/2018] [Accepted: 04/04/2018] [Indexed: 01/19/2023]
Abstract
Tumor associated macrophages are potential targets of the immune therapy for patients with colon cancer. PKCα acts as a tumor suppressor in the intestine. However, the correlation between PKCα expressed in colon cancer cells and tumor associated macrophages polarization has never been detected. In the present study, the correlation between PKCα expression and level of M1 macrophages was evaluated in human colon cancer tissues. A xenograft mouse model of colon cancer cells with different PKCα expression level was constructed to evaluate the effect of PKCα on M1 macrophages polarization in vivo. Co-culture of colon cancer cells and differentiated macrophages was used to detect the potential interplay in vitro. PKCα regulated production of cytokines which correlated with macrophage polarization and the underlying mechanism was further explored. Our study showed that high PKCα expression in human colon cancer tissues correlated with better prognosis and high M1 macrophage content. PKCα expressed in colon cancer cells inhibited the growth of colon cancer in mice model. PKCα induced macrophages polarized to the M1-like phenotype both in vitro and in vivo. Mechanistically, PKCα targeted P38 via MKK3/6 to promote IL12 and GM-CSF expression which further enhanced M1-like macrophages polarization. In conclusion, this study provided evidence for the first time that PKCα in colon cancer cells play an anticancer action by inducing the polarization of tumor associated macrophages to M1-like phenotype in the tumor microenvironment. PKCα promoted IL12/GM-CSF-mediated M1 polarization through MKK3/6-P38 signaling pathway. Our investigation suggested that modulation of the PKCα signaling pathway might serve as a novel strategy for colon cancer therapy.
Collapse
Affiliation(s)
- Yang Cheng
- Department of Digestive, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China.,Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yun Zhu
- Liver Tumor Center, Department of Infectious Diseases and Hepatology Unit, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Wanfu Xu
- Department of Digestive, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China.,Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Jiajia Xu
- Department of Digestive, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China.,Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Min Yang
- Department of Digestive, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Peiyu Chen
- Department of Digestive, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Junhong Zhao
- Department of Digestive, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Lanlan Geng
- Department of Digestive, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Sitang Gong
- Department of Digestive, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| |
Collapse
|
7
|
Oncolytic activity of a coxsackievirus B3 strain in human endometrial cancer cell lines. Virol J 2018; 15:65. [PMID: 29631630 PMCID: PMC5891967 DOI: 10.1186/s12985-018-0975-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 04/02/2018] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Endometrial cancer (EC) is one of the most common gynecological malignancies globally. Although progress has been made in surgical and other adjuvant therapies, there is still a great need to develop new approaches to further reduce the incidence and mortality of EC. Oncolytic virotherapy offers a novel promising option of cancer treatment and has demonstrated good efficacy in preclinical models and clinical trials. However, only few oncolytic viruses have been tested for EC treatment. In this study, the potential of an oncolytic coxsackievirus B3 (CV-B3) strain 2035A (CV-B3/2035A) was investigated as a novel biotherapeutic agent against EC. METHODS Human EC cell lines (Ishikawa, HEC-1-A and HEC-1-B) were infected with CV-B3/2035A, and viral replication and cytotoxic effects were evaluated in vitro. CV-B3/2035A-induced oncolysis was also investigated in nude mice bearing EC xenografts in vivo and in patient-derived EC samples ex vivo. RESULTS Human EC cell lines expressing different levels of CAR and DAF were all susceptible to infection by CV-B3/2035A and supported efficient viral replication in vitro. In the EC xenograft/nude mouse model, both intratumoral and intravenous administrations of CV-B3-2035A exerted significant therapeutic effects against pre-established EC tumors without causing significant treatment-related toxicity and mortality in nude mice. Moreover, CV-B3/2035A treatment resulted in decreased viability of patient-derived EC samples ex vivo. CONCLUSIONS CV-B3/2035A showed oncolytic activity in human EC cell lines both in vitro and in vivo as well as in patient-derived EC samples ex vivo and thus could be used as an alternative virotherapy agent for the treatment of EC.
Collapse
|
8
|
Li Y, Hu K, Yu Y, Rotenberg SA, Amatore C, Mirkin MV. Direct Electrochemical Measurements of Reactive Oxygen and Nitrogen Species in Nontransformed and Metastatic Human Breast Cells. J Am Chem Soc 2017; 139:13055-13062. [DOI: 10.1021/jacs.7b06476] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Yun Li
- Department
of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367, United States
| | - Keke Hu
- Department
of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367, United States
- The Graduate Center of the City University of New York, New York, New York 10016, United States
| | - Yun Yu
- Department
of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367, United States
- The Graduate Center of the City University of New York, New York, New York 10016, United States
| | - Susan A. Rotenberg
- Department
of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367, United States
- The Graduate Center of the City University of New York, New York, New York 10016, United States
| | - Christian Amatore
- PASTEUR,
Département de Chimie, École Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC Univ. Paris 06, CNRS, 24 rue Lhomond, Paris 75005, France
- State
Key Laboratory of Structural Chemistry, Fujian Institute
of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
| | - Michael V. Mirkin
- Department
of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367, United States
- The Graduate Center of the City University of New York, New York, New York 10016, United States
| |
Collapse
|
9
|
Chen S, Wang Y, Zhang Y, Wan Y. Low expression of PKCα and high expression of KRAS predict poor prognosis in patients with colorectal cancer. Oncol Lett 2016; 12:1655-1660. [PMID: 27602102 PMCID: PMC4998155 DOI: 10.3892/ol.2016.4845] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 03/08/2016] [Indexed: 01/13/2023] Open
Abstract
The current study aimed to determine the association between protein kinase Cα (PKCα) and Kirsten rat sarcoma viral oncogene homolog (KRAS) expression and the response to folinic acid, 5-fluorouracil and oxaliplatin (FOLFOX regimen) in patients with colorectal cancer (CRC). The protein levels of PKCα and KRAS were analyzed by immunohistochemistry in tissue samples from patients with CRC and in non-cancerous tissues, including 152 cases of colorectal adenocarcinoma, 30 cases of colorectal adenoma and 20 normal colonic mucosa samples. The association between PKCα and KRAS expression and clinicopathological features was analyzed. The rates of positive PKCα protein expression in patients with poorly, moderately and well-differentiated adenocarcinoma were 16.7% (6/36), 40.0% (24/60), and 57.1% (32/56), respectively (P<0.013). The rate of positive KRAS expression in CRC patients was significantly higher than in patients with colon adenoma and normal colon mucosa (P<0.001). Expression levels of KRAS were associated with the degree of differentiation of CRC (P<0.001). Expression of PKCα was negatively correlated with KRAS expression in CRC tissues. The mean progression-free survival (PFS) times in patients with high and low expression of PKCα were 43.9 and 38.8 months, respectively (P<0.001). The mean PFS times were 38.5 and 45.5 months in patients with high and low expression of KRAS, respectively (P=0.001). In conclusion, low PKCα and high KRAS expression predicted relatively poor prognosis in patients with CRC.
Collapse
Affiliation(s)
- Suxian Chen
- Department of Pathology, The Third Affiliated Hospital of Liaoning Medical College, Jinzhou, Liaoning 121002, P.R. China
| | - Yadi Wang
- Department of Oncology, The Third Affiliated Hospital of Liaoning Medical College, Jinzhou, Liaoning 121002, P.R. China
| | - Yun Zhang
- Department of Obstetrics and Gynecology, The Third Affiliated Hospital of Liaoning Medical College, Jinzhou, Liaoning 121002, P.R. China
| | - Yizeng Wan
- Department of Pathology, The Third Affiliated Hospital of Liaoning Medical College, Jinzhou, Liaoning 121002, P.R. China
- Correspondence to: Dr Yizeng Wan, Department of Pathology, The Third Affiliated Hospital of Liaoning Medical College, 2 Heping Road Section 5, Linghe, Jinzhou, Liaoning 121002, P.R. China, E-mail:
| |
Collapse
|
10
|
Vaškovičová K, Szabadosová E, Čermák V, Gandalovičová A, Kasalová L, Rösel D, Brábek J. PKCα promotes the mesenchymal to amoeboid transition and increases cancer cell invasiveness. BMC Cancer 2015; 15:326. [PMID: 25924946 PMCID: PMC4423130 DOI: 10.1186/s12885-015-1347-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 04/22/2015] [Indexed: 12/13/2022] Open
Abstract
Background The local invasion of tumor cells into the surrounding tissue is the first and most critical step of the metastatic cascade. Cells can invade either collectively, or individually. Individual cancer cell invasion can occur in the mesenchymal or amoeboid mode, which are mutually interchangeable. This plasticity of individual cancer cell invasiveness may represent an escape mechanism for invading cancer cells from anti-metastatic treatment. Methods To identify new signaling proteins involved in the plasticity of cancer cell invasiveness, we performed proteomic analysis of the amoeboid to mesenchymal transition with A375m2 melanoma cells in a 3D Matrigel matrix. Results In this screen we identified PKCα as an important protein for the maintenance of amoeboid morphology. We found that the activation of PKCα resulted in the mesenchymal-amoeboid transition of mesenchymal K2 and MDA-MB-231 cell lines. Consistently, PKCα inhibition led to the amoeboid-mesenchymal transition of amoeboid A375m2 cells. Next, we showed that PKCα inhibition resulted in a considerable decrease in the invading abilities of all analyzed cancer cell lines. Conclusions Our results suggest that PKCα is an important protein for maintenance of the amoeboid morphology of cancer cells, and that downregulation of PKCα results in the amoeboid to mesenchymal transition. Our data also suggest that PKCα is important for both mesenchymal and amoeboid invasiveness, making it an attractive target for anti-metastatic therapies. Electronic supplementary material The online version of this article (doi:10.1186/s12885-015-1347-1) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Katarína Vaškovičová
- Department of Cell Biology, Laboratory of Cancer Cell Invasion, Charles University in Prague, Prague, Czech Republic. .,Current affiliation: Microscopy Unit, Institute of Experimental Medicine, The Czech Academy of Sciences, Prague, Czech Republic.
| | - Emilia Szabadosová
- Department of Cell Biology, Laboratory of Cancer Cell Invasion, Charles University in Prague, Prague, Czech Republic.
| | - Vladimír Čermák
- Department of Cell Biology, Laboratory of Cancer Cell Invasion, Charles University in Prague, Prague, Czech Republic.
| | - Aneta Gandalovičová
- Department of Cell Biology, Laboratory of Cancer Cell Invasion, Charles University in Prague, Prague, Czech Republic.
| | - Lenka Kasalová
- Department of Cell Biology, Laboratory of Cancer Cell Invasion, Charles University in Prague, Prague, Czech Republic.
| | - Daniel Rösel
- Department of Cell Biology, Laboratory of Cancer Cell Invasion, Charles University in Prague, Prague, Czech Republic.
| | - Jan Brábek
- Department of Cell Biology, Laboratory of Cancer Cell Invasion, Charles University in Prague, Prague, Czech Republic.
| |
Collapse
|
11
|
Overexpressed PKCδ downregulates the expression of PKCα in B16F10 melanoma: induction of apoptosis by PKCδ via ceramide generation. PLoS One 2014; 9:e91656. [PMID: 24632809 PMCID: PMC3954766 DOI: 10.1371/journal.pone.0091656] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 02/12/2014] [Indexed: 02/06/2023] Open
Abstract
In the present study, we observed a marked variation in the expression of PKCα and PKCδ isotypes in B16F10 melanoma tumor cells compared to the normal melanocytes. Interestingly, the tumor instructed expression or genetically manipulated overexpression of PKCα isotype resulted in enhanced G1 to S transition. This in turn promoted cellular proliferation by activating PLD1 expression and subsequent AKT phosphorylation, which eventually resulted in suppressed ceramide generation and apoptosis. On the other hand, B16F10 melanoma tumors preferentially blocked the expression of PKCδ isotype, which otherwise could exhibit antagonistic effects on PKCα-PLD1-AKT signaling and rendered B16F10 cells more sensitive to apoptosis via generating ceramide and subsequently triggering caspase pathway. Hence our data suggested a reciprocal PKC signaling operational in B16F10 melanoma cells, which regulates ceramide generation and provide important clues to target melanoma cancer by manipulating the PKCδ-ceramide axis.
Collapse
|
12
|
Ziemba BP, Li J, Landgraf KE, Knight JD, Voth GA, Falke JJ. Single-molecule studies reveal a hidden key step in the activation mechanism of membrane-bound protein kinase C-α. Biochemistry 2014; 53:1697-713. [PMID: 24559055 PMCID: PMC3971957 DOI: 10.1021/bi4016082] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
![]()
Protein
kinase C-α (PKCα) is a member of the conventional
family of protein kinase C isoforms (cPKCs) that regulate diverse
cellular signaling pathways, share a common activation mechanism,
and are linked to multiple pathologies. The cPKC domain structure
is modular, consisting of an N-terminal pseudosubstrate peptide, two
inhibitory domains (C1A and C1B), a targeting domain (C2), and a kinase
domain. Mature, cytoplasmic cPKCs are inactive until they are switched
on by a multistep activation reaction that occurs largely on the plasma
membrane surface. Often, this activation begins with a cytoplasmic
Ca2+ signal that triggers C2 domain targeting to the plasma
membrane where it binds phosphatidylserine (PS) and phosphatidylinositol
4,5-bisphosphate (PIP2). Subsequently, the appearance of
the signaling lipid diacylglycerol (DAG) activates the membrane-bound
enzyme by recruiting the inhibitory pseudosubstrate and one or both
C1 domains away from the kinase domain. To further investigate this
mechanism, this study has utilized single-molecule total internal
reflection fluorescence microscopy (TIRFM) to quantitate the binding
and lateral diffusion of full-length PKCα and fragments missing
specific domain(s) on supported lipid bilayers. Lipid binding events,
and events during which additional protein is inserted into the bilayer,
were detected by their effects on the equilibrium bound particle density
and the two-dimensional diffusion rate. In addition to the previously
proposed activation steps, the findings reveal a major, undescribed,
kinase-inactive intermediate. On bilayers containing PS or PS and
PIP2, full-length PKCα first docks to the membrane
via its C2 domain, and then its C1A domain embeds itself in the bilayer
even before DAG appears. The resulting pre-DAG intermediate with membrane-bound
C1A and C2 domains is the predominant state of PKCα while it
awaits the DAG signal. The newly detected, membrane-embedded C1A domain
of this pre-DAG intermediate confers multiple useful features, including
enhanced membrane affinity and longer bound state lifetime. The findings
also identify the key molecular step in kinase activation: because
C1A is already membrane-embedded in the kinase off state, recruitment
of C1B to the bilayer by DAG or phorbol ester is the key regulatory
event that stabilizes the kinase on state. More broadly, this study
illustrates the power of single-molecule methods in elucidating the
activation mechanisms and hidden regulatory states of membrane-bound
signaling proteins.
Collapse
Affiliation(s)
- Brian P Ziemba
- Department of Chemistry and Biochemistry and Molecular Biophysics Program, University of Colorado , Boulder, Colorado 80309-0596, United States
| | | | | | | | | | | |
Collapse
|
13
|
Du HF, Ou LP, Yang X, Song XD, Fan YR, Tan B, Luo CL, Wu XH. A new PKCα/β/TBX3/E-cadherin pathway is involved in PLCε-regulated invasion and migration in human bladder cancer cells. Cell Signal 2013; 26:580-93. [PMID: 24316392 DOI: 10.1016/j.cellsig.2013.11.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 11/11/2013] [Accepted: 11/14/2013] [Indexed: 11/25/2022]
Abstract
Although PLCε has been verified to enhance bladder cancer cell invasion, the signaling pathways responsible for this remain elusive. Protein kinase C (PKCα/β), which is involved in cancer development and progression, has been demonstrated to be activated by PLCε. However, the roles of PKCα/β in PLCε-mediated bladder carcinoma cell invasion and migration have not been clearly identified. In this study, to determine what role PKCα/β plays in PLCε-mediated bladder cancer cell invasion and migration, we silenced PLCε gene by adenovirus-shPLCε in T24 and BIU-87 cells and then revealed that it significantly inhibited cell migration and invasion. Further research indicated that cell bio-function of PLCε-regulated was related with PKCα/β activity. These in vitro findings were supported by data from bladder carcinoma patient samples. In 35 case bladder cancer tumor samples, PLCε-overexpressing tumors showed significantly higher positive rates of PKCα/β membrane immunohistochemistry staining than PLCε-low-expressing tumors. Mechanistically, study further showed that PLCε knockdown gene induced E-cadherin expression and decreased TBX3 expression, both of which were dependent on PKCα/β activity. In addition, we demonstrated that treatment cells with TBX3-specific shorting hairpin RNA (shRNA) up-regulated E-cadherin expression and inhibited cell invasion/migration. Moreover, in in vivo experiment, immunohistochemistry analysis of Ad-shPLCε-infected tumor tissue showed low expression levels of phospho-PKCα/β and TBX3 and high expression levels of E-cadherin compared with those of the control group. In summary, our findings uncover that PKCα/β is critical for PLCε-mediated cancer cell invasion and migration and provide valuable insights for current and future Ad-shPLCε and PKCα/β clinical trials.
Collapse
Affiliation(s)
- Hong Fei Du
- The Key Laboratory of Diagnostics Medicine designated by the Ministry of Education, Chongqing Medical University, Chongqing, People's Republic of China
| | - Li Ping Ou
- The Key Laboratory of Diagnostics Medicine designated by the Ministry of Education, Chongqing Medical University, Chongqing, People's Republic of China
| | - Xue Yang
- The Key Laboratory of Diagnostics Medicine designated by the Ministry of Education, Chongqing Medical University, Chongqing, People's Republic of China
| | - Xue Dong Song
- The Key Laboratory of Diagnostics Medicine designated by the Ministry of Education, Chongqing Medical University, Chongqing, People's Republic of China
| | - Yan Ru Fan
- The Key Laboratory of Diagnostics Medicine designated by the Ministry of Education, Chongqing Medical University, Chongqing, People's Republic of China
| | - Bing Tan
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China
| | - Chun Li Luo
- The Key Laboratory of Diagnostics Medicine designated by the Ministry of Education, Chongqing Medical University, Chongqing, People's Republic of China.
| | - Xiao Hou Wu
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China
| |
Collapse
|
14
|
Dong P, Kaneuchi M, Watari H, Sudo S, Sakuragi N. MicroRNA-106b modulates epithelial-mesenchymal transition by targeting TWIST1 in invasive endometrial cancer cell lines. Mol Carcinog 2013; 53:349-59. [PMID: 24002805 DOI: 10.1002/mc.21983] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 10/25/2012] [Indexed: 12/19/2022]
Abstract
Type II endometrial carcinoma is an aggressive subtype of endometrial cancer (EC). TWIST1, a helix-loop-helix transcription regulator, is known to induce epithelial-mesenchymal transition (EMT) and promote tumor metastasis. MicroRNAs (miRNAs) also serve as important regulators of EMT and metastasis by regulating EMT-related genes. In this study, we sought to explore the role of TWIST1 in inducing EMT in representative type II EC cell lines, and to determine the miRNAs involved in regulating TWIST1 gene expression. Functional analysis suggested that TWIST1 contributes to the EMT phenotypes of EC cells, as evidenced by the acquisition of fibroblast-like properties, enhanced invasiveness, and induction of an EN-switch (downregulation of epithelial marker E-cadherin and upregulation of mesenchymal marker N-cadherin). Conversely, silencing of TWIST1 by siRNA inhibited cell invasion and the mesenchymal phenotype, which was accompanied by a reversion of the EN-switch. We also observed a novel post-transcriptional regulatory mechanism of TWIST1 expression mediated by miR-106b via its direct interaction with TWIST1 mRNAs at the 3'-untranslated region. Our data suggest that TWIST1 is a critical inducer of EMT in invasive EC cells and that miR-106b could suppress EC cell invasion by downregulating TWIST1 expression.
Collapse
Affiliation(s)
- Peixin Dong
- Department of Women's Health Educational System, Hokkaido University School of Medicine, Hokkaido University, Sapporo, Japan
| | | | | | | | | |
Collapse
|
15
|
Thorne AM, Jackson TA, Willis VC, Bradford AP. Protein Kinase C α Modulates Estrogen-Receptor-Dependent Transcription and Proliferation in Endometrial Cancer Cells. Obstet Gynecol Int 2013; 2013:537479. [PMID: 23843797 PMCID: PMC3703424 DOI: 10.1155/2013/537479] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 05/31/2013] [Indexed: 11/18/2022] Open
Abstract
Endometrial cancer is the most common invasive gynecologic malignancy in developed countries. The most prevalent endometrioid tumors are linked to excessive estrogen exposure and hyperplasia. However, molecular mechanisms and signaling pathways underlying their etiology and pathophysiology remain poorly understood. We have shown that protein kinase C α (PKC α ) is aberrantly expressed in endometrioid tumors and is an important mediator of endometrial cancer cell survival, proliferation, and invasion. In this study, we demonstrate that expression of active, myristoylated PKC α conferred ligand-independent activation of estrogen-receptor- (ER-) dependent promoters and enhanced responses to estrogen. Conversely, knockdown of PKC α reduced ER-dependent gene expression and inhibited estrogen-induced proliferation of endometrial cancer cells. The ability of PKC α to potentiate estrogen activation of ER-dependent transcription was attenuated by inhibitors of phosphoinositide 3-kinase (PI3K) and Akt. Evidence suggests that PKC α and estrogen signal transduction pathways functionally interact, to modulate ER-dependent growth and transcription. Thus, PKC α signaling, via PI3K/Akt, may be a critical element of the hyperestrogenic environment and activation of ER that is thought to underlie the development of estrogen-dependent endometrial hyperplasia and malignancy. PKC α -dependent pathways may provide much needed prognostic markers of aggressive disease and novel therapeutic targets in ER positive tumors.
Collapse
Affiliation(s)
- Alicia M. Thorne
- Department of Obstetrics and Gynecology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Twila A. Jackson
- Department of Obstetrics and Gynecology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Van C. Willis
- Division of Rheumatology, Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Andrew P. Bradford
- Department of Obstetrics and Gynecology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| |
Collapse
|
16
|
Lin SC, Chen WY, Lin KY, Chen SH, Chang CC, Lin SE, Fang CL. Clinicopathological correlation and prognostic significance of protein kinase cα overexpression in human gastric carcinoma. PLoS One 2013; 8:e56675. [PMID: 23468872 PMCID: PMC3582558 DOI: 10.1371/journal.pone.0056675] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 01/16/2013] [Indexed: 01/24/2023] Open
Abstract
OBJECTIVES This study investigated the PKCα protein expression in gastric carcinoma, and correlated it with clinicopathological parameters. The prognostic significance of PKCα protein expression in gastric carcinoma was analyzed. METHODS Quantitative real-time PCR test was applied to compare the PKCα mRNA expression in tumorous and nontumorous tissues of gastric carcinoma in ten randomly selected cases. Then PKCα protein expression was evaluated in 215 cases of gastric carcinoma using immunohistochemical method. The immunoreactivity was scored semiquantitatively as: 0 = absent; 1 = weak; 2 = moderate; and 3 = strong. All cases were further classified into two groups, namely PKCα overexpression group with score 2 or 3, and non-overexpression group with score 0 or 1. The PKCα protein expression was correlated with clinicopathological parameters. Survival analysis was performed to determine the prognostic significance of PKCα protein expression in patients with gastric carcinoma. RESULTS PKCα mRNA expression was upregulated in all ten cases of gastric carcinoma via quantitative real-time PCR test. In immunohistochemical study, eighty-eight out of 215 cases (41%) of gastric carcinoma revealed PKCα protein overexpression, which was statistically correlated with age (P = 0.0073), histologic type (P<0.0001), tumor differentiation (P = 0.0110), depth of invasion (P = 0.0003), angiolymphatic invasion (P = 0.0373), pathologic stage (P = 0.0047), and distant metastasis (P = 0.0048). We found no significant difference in overall and disease free survival rates between PKCα overexpression and non-overexpression groups (P = 0.0680 and 0.0587). However, PKCα protein overexpression emerged as a significant independent prognostic factor in multivariate Cox regression analysis (hazard ratio 0.632, P = 0.0415). CONCLUSIONS PKCα protein is upregulated in gastric carcinoma. PKCα protein expression is statistically correlated with age, histologic type, tumor differentiation, depth of invasion, angiolymphatic invasion, pathologic stage, and distant metastasis. The PKCα protein overexpression in patients with gastric carcinoma is a significant independent prognostic factor in multivariate Cox regression analysis.
Collapse
Affiliation(s)
- Shee-Chan Lin
- Division of Gastroenterology, Department of Internal Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Wei-Yu Chen
- Department of Pathology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Pathology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Kai-Yuan Lin
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan
- Department of Biotechnology, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Sheng-Hsuan Chen
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Gastroenterology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
| | - Chun-Chao Chang
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Gastroenterology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
| | - Sey-En Lin
- Department of Pathology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Pathology, Taipei Medical University Hospital, Taipei, Taiwan
| | - Chia-Lang Fang
- Department of Pathology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Pathology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| |
Collapse
|
17
|
Lauro G, Masullo M, Piacente S, Riccio R, Bifulco G. Inverse Virtual Screening allows the discovery of the biological activity of natural compounds. Bioorg Med Chem 2012; 20:3596-602. [DOI: 10.1016/j.bmc.2012.03.072] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 03/26/2012] [Accepted: 03/30/2012] [Indexed: 12/17/2022]
|
18
|
Taniuchi K, Yokotani K, Saibara T. BART inhibits pancreatic cancer cell invasion by PKCα inactivation through binding to ANX7. PLoS One 2012; 7:e35674. [PMID: 22532868 PMCID: PMC3330813 DOI: 10.1371/journal.pone.0035674] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2012] [Accepted: 03/19/2012] [Indexed: 11/27/2022] Open
Abstract
A novel function for the binder of Arl two (BART) molecule in pancreatic cancer cells is reported. BART inhibits invasiveness of pancreatic cancer cells through binding to a Ca2+-dependent, phosphorylated, guanosine triphosphatase (GTPase) membrane fusion protein, annexin7 (ANX7). A tumor suppressor function for ANX7 was previously reported based on its prognostic role in human cancers and the cancer-prone mouse phenotype ANX7(+/−). Further investigation demonstrated that the BART–ANX7 complex is transported toward cell protrusions in migrating cells when BART supports the binding of ANX7 to the protein kinase C (PKC) isoform PKCα. Recent evidence has suggested that phosphorylation of ANX7 by PKC significantly potentiates ANX7-induced fusion of phospholipid vesicles; however, the current data suggest that the BART–ANX7 complex reduces PKCα activity. Knocking down endogenous BART and ANX7 increases activity of PKCα, and specific inhibitors of PKCα significantly abrogate invasiveness induced by BART and ANX7 knockdown. These results imply that BART contributes to regulating PKCα activity through binding to ANX7, thereby affecting the invasiveness of pancreatic cancer cells. Thus, it is possible that BART and ANX7 can distinctly regulate the downstream signaling of PKCα that is potentially relevant to cell invasion by acting as anti-invasive molecules.
Collapse
Affiliation(s)
- Keisuke Taniuchi
- Department of Pharmacology, School of Medicine, Kochi University, Nankoku, Kochi, Japan.
| | | | | |
Collapse
|
19
|
Involvement of the PLCε/PKCα pathway in human BIU-87 bladder cancer cell proliferation. Cell Biol Int 2012; 35:1031-6. [PMID: 21121899 DOI: 10.1042/cbi20090101] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PLCε (phospholipase Cε), one of effectors belonging to the small GTPase superfamily, has been suggested to play a crucial role in carcinogenesis. However, its bio-function in bladder cancer has never been demonstrated. In our previous study, we found that PLCε mRNA was highly expressed in bladder cancer tissues. In the present study, we silenced the PLCε gene by shRNA (small-hairpin RNA) in the bladder cancer cell line BIU-87. The results showed that it significantly inhibited cell proliferation and arrested the cell cycle at G0/G1-phase. The regulation of cell characteristics has been related to PKCα (protein kinase Cα) activity. Further study showed that knockdown of the PLCε gene down-regulated oncogenes c-fos and c-jun. These results indicate that PLCε plays a crucial role in bladder cancer, and PLCε may be a key molecule regulating the signal pathway of bladder cancer proliferation.
Collapse
|
20
|
Ziv-Av A, Taller D, Attia M, Xiang C, Lee HK, Cazacu S, Finniss S, Kazimirsky G, Sarid R, Brodie C. RTVP-1 expression is regulated by SRF downstream of protein kinase C and contributes to the effect of SRF on glioma cell migration. Cell Signal 2011; 23:1936-43. [PMID: 21777672 DOI: 10.1016/j.cellsig.2011.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 07/04/2011] [Indexed: 01/13/2023]
Abstract
Gliomas are characterized by increased infiltration into the surrounding normal brain tissue. We recently reported that RTVP-1 is highly expressed in gliomas and plays a role in the migration of these cells, however the regulation of RTVP-1 expression in these cells is not yet described. In this study we examined the role of PKC in the regulation of RTVP-1 expression and found that PMA and overexpression of PKCα and PKCε increased the expression of RTVP-1, whereas PKCδ exerted an opposite effect. Using the MatInspector software, we identified a SRF binding site on the RTVP-1 promoter. Chromatin immunoprecipitation (ChIP) assay revealed that SRF binds to the RTVP-1 promoter in U87 cells, and that this binding was significantly increased in response to serum addition. Moreover, silencing of SRF blocked the induction of RTVP-1 expression in response to serum. We found that overexpression of PKCα and PKCε increased the activity of the RTVP-1 promoter and the binding of SRF to the promoter. In contrast, overexpression of PKCδ blocked the increase in RTVP-1 expression in response to serum and the inhibitory effect of PKCδ was abrogated in cells expressing a SRFT160A mutant. SRF regulated the migration of glioma cells and its effect was partially mediated by RTVP-1. We conclude that RTVP-1 is a PKC-regulated gene and that this regulation is at least partly mediated by SRF. Moreover, RTVP-1 plays a role in the effect of SRF on glioma cell migration.
Collapse
Affiliation(s)
- Amotz Ziv-Av
- The Mina and Everard Goodman Faculty of Life-Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | | | | | | | | | | | | | | | | | | |
Collapse
|