1
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Hu B, Liu G, Zhao K, Zhang G. Diversity of extracellular HSP70 in cancer: advancing from a molecular biomarker to a novel therapeutic target. Front Oncol 2024; 14:1388999. [PMID: 38646439 PMCID: PMC11026673 DOI: 10.3389/fonc.2024.1388999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 03/25/2024] [Indexed: 04/23/2024] Open
Abstract
Heat shock protein 70 (HSP70) is a highly conserved protein functioning as a "molecular chaperone", which is integral to protein folding and maturation. In addition to its high expression within cells upon stressful challenges, HSP70 can be translocated to the cell membrane or released from cells in free form or within extracellular vesicles (EVs). Such trafficking of HSP70 is also present in cancer cells, as HSP70 is overexpressed in various types of patient samples across a range of common malignancies, signifying that extracellular HSP70 (eHSP70) can serve as a tumor biomarker. eHSP70 is involved in a broad range of cancer-related events, including cell proliferation and apoptosis, extracellular matrix (ECM) remodeling, epithelial-mesenchymal transition (EMT), angiogenesis, and immune response. eHSP70 can also induce cancer cell resistance to various treatments, such as chemotherapy, radiotherapy, and anti-programmed death-1 (PD-1) immunotherapy. Though the role of eHSP70 in tumors is contradictory, characterized by both pro-tumor and anti-tumor effects, eHSP70 serves as a promising target in cancer treatment. In this review, we comprehensively summarized the current knowledge about the role of eHSP70 in cancer progression and treatment resistance and discussed the feasibility of eHSP70 as a cancer biomarker and therapeutic target.
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Affiliation(s)
- Binbin Hu
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Guihong Liu
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Kejia Zhao
- Department of Thoracic Surgery and Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Western China Collaborative Innovation Center for Early Diagnosis and Multidisciplinary Therapy of Lung Cancer, Chengdu, Sichuan, China
| | - Gao Zhang
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
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2
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Kuo CL, Ponneri Babuharisankar A, Lin YC, Lien HW, Lo YK, Chou HY, Tangeda V, Cheng LC, Cheng AN, Lee AYL. Mitochondrial oxidative stress in the tumor microenvironment and cancer immunoescape: foe or friend? J Biomed Sci 2022; 29:74. [PMID: 36154922 PMCID: PMC9511749 DOI: 10.1186/s12929-022-00859-2] [Citation(s) in RCA: 68] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 09/19/2022] [Indexed: 12/07/2022] Open
Abstract
The major concept of "oxidative stress" is an excess elevated level of reactive oxygen species (ROS) which are generated from vigorous metabolism and consumption of oxygen. The precise harmonization of oxidative stresses between mitochondria and other organelles in the cell is absolutely vital to cell survival. Under oxidative stress, ROS produced from mitochondria and are the major mediator for tumorigenesis in different aspects, such as proliferation, migration/invasion, angiogenesis, inflammation, and immunoescape to allow cancer cells to adapt to the rigorous environment. Accordingly, the dynamic balance of oxidative stresses not only orchestrate complex cell signaling events in cancer cells but also affect other components in the tumor microenvironment (TME). Immune cells, such as M2 macrophages, dendritic cells, and T cells are the major components of the immunosuppressive TME from the ROS-induced inflammation. Based on this notion, numerous strategies to mitigate oxidative stresses in tumors have been tested for cancer prevention or therapies; however, these manipulations are devised from different sources and mechanisms without established effectiveness. Herein, we integrate current progress regarding the impact of mitochondrial ROS in the TME, not only in cancer cells but also in immune cells, and discuss the combination of emerging ROS-modulating strategies with immunotherapies to achieve antitumor effects.
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Affiliation(s)
- Cheng-Liang Kuo
- National Institute of Cancer Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 35053, Taiwan
| | - Ananth Ponneri Babuharisankar
- National Institute of Cancer Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 35053, Taiwan.,Joint PhD Program in Molecular Medicine, NHRI & NCU, Zhunan, Miaoli, 35053, Taiwan
| | - Ying-Chen Lin
- National Institute of Cancer Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 35053, Taiwan
| | - Hui-Wen Lien
- National Institute of Cancer Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 35053, Taiwan
| | - Yu Kang Lo
- National Institute of Cancer Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 35053, Taiwan
| | - Han-Yu Chou
- National Institute of Cancer Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 35053, Taiwan
| | - Vidhya Tangeda
- National Institute of Cancer Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 35053, Taiwan.,Joint PhD Program in Molecular Medicine, NHRI & NCU, Zhunan, Miaoli, 35053, Taiwan
| | - Li-Chun Cheng
- Liver Research Center, Linkou Chang Gung Memorial Hospital, Taoyuan, 333, Taiwan
| | - An Ning Cheng
- Genomics Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Alan Yueh-Luen Lee
- National Institute of Cancer Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli, 35053, Taiwan. .,Joint PhD Program in Molecular Medicine, NHRI & NCU, Zhunan, Miaoli, 35053, Taiwan. .,Department of Life Sciences, College of Health Sciences and Technology, National Central University, Zhongli, Taoyuan, 32001, Taiwan. .,Graduate Institute of Biomedical Sciences, China Medical University, Taichung, 40402, Taiwan. .,Department of Biotechnology, College of Life Science, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan.
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3
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Wang Y, Peng D, Huang Y, Cao Y, Li H, Zhang X. Podoplanin: Its roles and functions in neurological diseases and brain cancers. Front Pharmacol 2022; 13:964973. [PMID: 36176432 PMCID: PMC9514838 DOI: 10.3389/fphar.2022.964973] [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: 06/09/2022] [Accepted: 08/22/2022] [Indexed: 11/28/2022] Open
Abstract
Podoplanin is a small mucin-like glycoprotein involved in several physiological and pathological processes in the brain including development, angiogenesis, tumors, ischemic stroke and other neurological disorders. Podoplanin expression is upregulated in different cell types including choroid plexus epithelial cells, glial cells, as well as periphery infiltrated immune cells during brain development and neurological disorders. As a transmembrane protein, podoplanin interacts with other molecules in the same or neighboring cells. In the past, a lot of studies reported a pleiotropic role of podoplanin in the modulation of thrombosis, inflammation, lymphangiogenesis, angiogenesis, immune surveillance, epithelial mesenchymal transition, as well as extracellular matrix remodeling in periphery, which have been well summarized and discussed. Recently, mounting evidence demonstrates the distribution and function of this molecule in brain development and neurological disorders. In this review, we summarize the research progresses in understanding the roles and mechanisms of podoplanin in the development and disorders of the nervous system. The challenges of podoplanin-targeted approaches for disease prognosis and preventions are also discussed.
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Affiliation(s)
- Yi Wang
- Department of Neurology, The Second Affiliated Hospital of Soochow University and Clinical Research Center of Neurological Disease, Suzhou, China
| | - Dan Peng
- Department of Neurology, The Second Affiliated Hospital of Soochow University and Clinical Research Center of Neurological Disease, Suzhou, China
| | - Yaqian Huang
- Department of Neurology, The Second Affiliated Hospital of Soochow University and Clinical Research Center of Neurological Disease, Suzhou, China
| | - Yongjun Cao
- Department of Neurology, The Second Affiliated Hospital of Soochow University and Clinical Research Center of Neurological Disease, Suzhou, China
| | - Hui Li
- Department of Cardiology, The Second Affiliated Hospital of Soochow University, Suzhou, China
- *Correspondence: Hui Li, ; Xia Zhang,
| | - Xia Zhang
- Department of Neurology, The Second Affiliated Hospital of Soochow University and Clinical Research Center of Neurological Disease, Suzhou, China
- *Correspondence: Hui Li, ; Xia Zhang,
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4
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Wang G, Fan Y, Cao P, Tan K. Insight into the mitochondrial unfolded protein response and cancer: opportunities and challenges. Cell Biosci 2022; 12:18. [PMID: 35180892 PMCID: PMC8857832 DOI: 10.1186/s13578-022-00747-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 01/18/2022] [Indexed: 02/08/2023] Open
Abstract
The mitochondrial unfolded protein response (UPRmt) is an evolutionarily conserved protective transcriptional response that maintains mitochondrial proteostasis by inducing the expression of mitochondrial chaperones and proteases in response to various stresses. The UPRmt-mediated transcriptional program requires the participation of various upstream signaling pathways and molecules. The factors regulating the UPRmt in Caenorhabditis elegans (C. elegans) and mammals are both similar and different. Cancer cells, as malignant cells with uncontrolled proliferation, are exposed to various challenges from endogenous and exogenous stresses. Therefore, in cancer cells, the UPRmt is hijacked and exploited for the repair of mitochondria and the promotion of tumor growth, invasion and metastasis. In this review, we systematically introduce the inducers of UPRmt, the biological processes in which UPRmt participates, the mechanisms regulating the UPRmt in C. elegans and mammals, cross-tissue signal transduction of the UPRmt and the roles of the UPRmt in promoting cancer initiation and progression. Disrupting proteostasis in cancer cells by targeting UPRmt constitutes a novel anticancer therapeutic strategy.
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Affiliation(s)
- Ge Wang
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Hebei, 050024, China.,Department of Human Anatomy, Histology and Embryology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), State Key Laboratory of Natural and Biomimetic Drugs, Peking University Health Science Center, Beijing, 100191, China
| | - Yumei Fan
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Hebei, 050024, China
| | - Pengxiu Cao
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Hebei, 050024, China
| | - Ke Tan
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Hebei, 050024, China.
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5
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The Role of Podoplanin in Skin Diseases. Int J Mol Sci 2022; 23:ijms23031310. [PMID: 35163233 PMCID: PMC8836045 DOI: 10.3390/ijms23031310] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/22/2022] [Accepted: 01/23/2022] [Indexed: 02/05/2023] Open
Abstract
Podoplanin is a sialomucin-like type I transmembrane receptor glycoprotein that is expressed specifically in lymphatic vessels, sebaceous glands, and hair follicles in normal skin. However, under pathological conditions podoplanin expression is upregulated in various cells, such as keratinocytes, fibroblasts, tumor cells, and inflammatory cells, and plays pivotal roles in different diseases. In psoriasis, podoplanin expression is induced in basal keratinocytes via the JAK-STAT pathway and contributes toward epidermal hyperproliferation. Podoplanin expression on keratinocytes can also promote IL-17 secretion from lymphocytes, promoting chronic inflammation. During wound healing, the podoplanin/CLEC-2 interaction between keratinocytes and platelets regulates re-epithelialization at the wound edge. In skin cancers, podoplanin expresses on tumor cells and promotes their migration and epithelial-mesenchymal transition, thereby accelerating invasion and metastasis. Podoplanin is also expressed in normal peritumoral cells, such as cancer-associated fibroblasts in melanoma and keratinocytes in extramammary Paget's disease, which promote tumor progression and predict aggressive behavior and poor prognosis. This review provides an overview of our current understanding of the mechanisms via which podoplanin mediates these pathological skin conditions.
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6
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Rai R, Kennedy AL, Isingizwe ZR, Javadian P, Benbrook DM. Similarities and Differences of Hsp70, hsc70, Grp78 and Mortalin as Cancer Biomarkers and Drug Targets. Cells 2021; 10:cells10112996. [PMID: 34831218 PMCID: PMC8616428 DOI: 10.3390/cells10112996] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 10/29/2021] [Accepted: 11/01/2021] [Indexed: 12/17/2022] Open
Abstract
Background: Upregulation of Heath Shock Protein 70 (HSP70) chaperones supports cancer cell survival. Their high homology causes a challenge to differentiate them in experimental or prevention and treatment strategies. The objective of this investigation was to determine similarities and differences of Hsp70, hsc70, Grp78 and Mortalin members of the HSP70 family encoded by HSPA1, HSPA8, HSPA5 and HSPA9 genes, respectively. Methods: Literature reviews were conducted using HSPA1, HSPA5, HSPA8 and HSPA9 gene or protein names or synonyms combined with biological or cancer-relevant terms. Ingenuity Pathway Analysis was used to identify and compare profiles of proteins that directly bind individual chaperones and their associated pathways. TCGA data was probed to identify associations of hsc70 with cancer patient survival. ClinicalTrials.gov was used to identify HSP70 family studies. Results: The chaperones have similar protein folding functions. Their different cellular effects are determined by co-chaperones and client proteins combined with their intra- and extra-cellular localizations. Their upregulation is associated with worse patient prognosis in multiple cancers and can stimulate tumor immune responses or drug resistance. Their inhibition selectively kills cancer over healthy cells. Conclusions: Differences in Hsp70, hsc70, Grp78 and mortalin provide opportunities to calibrate HSP70 inhibitors for individual cancers and combination therapies.
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Affiliation(s)
- Rajani Rai
- Gynecologic Oncology Section, Obstetrics and Gynecology Department, Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (R.R.); (P.J.)
| | - Amy L. Kennedy
- Pathology Department, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA;
| | - Zitha Redempta Isingizwe
- Pharmaceutical Sciences Department, Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA;
| | - Pouya Javadian
- Gynecologic Oncology Section, Obstetrics and Gynecology Department, Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (R.R.); (P.J.)
| | - Doris Mangiaracina Benbrook
- Gynecologic Oncology Section, Obstetrics and Gynecology Department, Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (R.R.); (P.J.)
- Pathology Department, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA;
- Pharmaceutical Sciences Department, Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA;
- Correspondence: ; Tel.: +1-405-271-5523
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7
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Nanamiya R, Takei J, Asano T, Sano M, Tanaka T, Hosono H, Harada H, Sakai Y, Mizuno T, Suzuki H, Kaneko MK, Kato Y. Ferret Podoplanin Is Detected by PMab-241 in Immunohistochemistry. Monoclon Antib Immunodiagn Immunother 2021; 40:134-140. [PMID: 34161160 DOI: 10.1089/mab.2021.0016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Podoplanin (PDPN) plays an important role in the development of many normal tissues and is expressed in various cancers. We have previously developed multiple monoclonal antibodies (mAbs) against PDPNs from a variety of animal species and characterized each of these PDPNs using the anti-PDPN mAbs. In this study, we evaluated whether these anti-PDPN mAbs possess cross-reactivity with ferret PDPN (ferPDPN) using flow cytometry. Comprehensive analysis using 17 differing anti-PDPN mAbs available for immunohistochemistry use, demonstrated that the anti-bear PDPN mAb (clone PMab-241) strongly cross-reacts with ferPDPN-overexpressed Chinese hamster ovary-K1 (CHO/ferPDPN) cells. Immunohistochemistry analysis demonstrated intense PMab-241 staining within Bowman's capsules and glomeruli of the ferret kidney, and lymphatic endothelial cells of the ferret lung. These results demonstrate that PMab-241 is suitable for the detection of PDPN in ferret tissues.
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Affiliation(s)
- Ren Nanamiya
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Junko Takei
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan.,Department of Oral and Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Teizo Asano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masato Sano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tomohiro Tanaka
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hideki Hosono
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroyuki Harada
- Department of Oral and Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yusuke Sakai
- Laboratory of Veterinary Pathology, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Takuya Mizuno
- Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Hiroyoshi Suzuki
- Department of Pathology and Laboratory Medicine, Sendai Medical Center, Sendai, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan.,New Industry Creation Hatchery Center, Tohoku University, Sendai, Japan
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8
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Seclì L, Fusella F, Avalle L, Brancaccio M. The dark-side of the outside: how extracellular heat shock proteins promote cancer. Cell Mol Life Sci 2021; 78:4069-4083. [PMID: 33544155 PMCID: PMC8164615 DOI: 10.1007/s00018-021-03764-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/28/2020] [Accepted: 01/15/2021] [Indexed: 02/07/2023]
Abstract
In addition to exerting several essential house-keeping activities in the cell, heat shock proteins (HSPs) are crucial players in a well-structured molecular program activated in response to stressful challenges. Among the different activities carried out by HSPs during emergency, they reach the extracellular milieu, from where they scout the surroundings, regulate extracellular protein activity and send autocrine and paracrine signals. Cancer cells permanently experience stress conditions due to their altered equilibrium and behaviour, and constantly secrete heat shock proteins as a result. Other than supporting anti-tumour immunity, extracellular heat shock proteins (eHSPs), can also exacerbate cancer cell growth and malignancy by sustaining different cancer hallmarks. eHSPs are implicated in extracellular matrix remodelling, resistance to apoptosis, promotion of cell migration and invasion, induction of epithelial to mesenchymal transition, angiogenesis and activation of stromal cells, supporting ultimately, metastasis dissemination. A broader understanding of eHSP activity and contribution to tumour development and progression is leading to new opportunities in the diagnosis and treatment of cancer.
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Affiliation(s)
- Laura Seclì
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Turin, Italy.
| | - Federica Fusella
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Turin, Italy
| | - Lidia Avalle
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Turin, Italy
| | - Mara Brancaccio
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Turin, Italy.
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9
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Li Z, Liu Y, Zhang H, Pu Z, Wu X, Li P. Effect of fosinopril on the renal cortex protein expression profile of Otsuka Long-Evans Tokushima Fatty rats. Exp Ther Med 2019; 19:172-182. [PMID: 31853288 PMCID: PMC6909786 DOI: 10.3892/etm.2019.8188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 08/23/2019] [Indexed: 12/21/2022] Open
Abstract
Angiotensin-converting enzyme inhibitors (ACEIs) can reduce urinary protein excretion and postpone the deterioration of renal function. However, the mechanisms of renal protection are not yet fully understood. To investigate the mechanisms of ACEIs in the treatment of diabetic nephropathy (DN), the present study determined the effects of the ACEI fosinopril (FP) on the profiling of renal cortex protein expression in Otsuka Long-Evans Tokushima Fatty (OLETF) rats using Long-Evans Tokushima Otsuka (LETO) rats as controls. Urinary protein levels at 24 h were examined using the Broadford method. PAS staining was performed to observe renal histopathological changes. The kidney cortices of OLETF, FP-treated OLETF and LETO rats were examined using soluble and insoluble high-resolution subproteomic analysis methodology at age of 36 and 56 weeks. Differentiated proteins were further confirmed using western blotting analysis. The results demonstrated that FP significantly decreased the glomerulosclerosis index and reduced the 24 h urinary protein excretion of OLETF rats. Additionally, 17 proteins significantly changed following FP-treatment. Amongst these proteins, the abundances of the stress-response protein heat shock protein family A member 9 and the antioxidant glutathione peroxidase 3 were particularly increased. These results indicated that FP ameliorated diabetic renal injuries by inhibiting oxidative stress. In conclusion, the differentially expressed proteins may improve our understanding of the mechanism of ACEIs in the OLETF rats.
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Affiliation(s)
- Zhiguo Li
- Department of Medical Research Center, International Science and Technology Cooperation Base of Geriatric Medicine, North China University of Science and Technology, Tangshan, Hebei 063210, P.R. China
| | - Yeqiang Liu
- Department of Endocrinology, Kailuan General Hospital, Tangshan, Hebei 063000, P.R. China
| | - Haojun Zhang
- Beijing Key Laboratory for Immune-Mediated Inflammatory Diseases, Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing 100029, P.R. China
| | - Zhijie Pu
- Graduate School, North China University of Science and Technology, Tangshan, Hebei 063000, P.R. China
| | - Xuejing Wu
- Graduate School, North China University of Science and Technology, Tangshan, Hebei 063000, P.R. China
| | - Ping Li
- Beijing Key Laboratory for Immune-Mediated Inflammatory Diseases, Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing 100029, P.R. China
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10
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Podoplanin in Inflammation and Cancer. Int J Mol Sci 2019; 20:ijms20030707. [PMID: 30736372 PMCID: PMC6386838 DOI: 10.3390/ijms20030707] [Citation(s) in RCA: 131] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/31/2019] [Accepted: 02/01/2019] [Indexed: 02/07/2023] Open
Abstract
Podoplanin is a small cell-surface mucin-like glycoprotein that plays a crucial role in the development of the alveoli, heart, and lymphatic vascular system. Emerging evidence indicates that it is also involved in the control of mammary stem-cell activity and biogenesis of platelets in the bone marrow, and exerts an important function in the immune response. Podoplanin expression is upregulated in different cell types, including fibroblasts, macrophages, T helper cells, and epithelial cells, during inflammation and cancer, where it plays important roles. Podoplanin is implicated in chronic inflammatory diseases, such as psoriasis, multiple sclerosis, and rheumatoid arthritis, promotes inflammation-driven and cancer-associated thrombosis, and stimulates cancer cell invasion and metastasis through a variety of strategies. To accomplish its biological functions, podoplanin must interact with other proteins located in the same cell or in neighbor cells. The binding of podoplanin to its ligands leads to modulation of signaling pathways that regulate proliferation, contractility, migration, epithelial⁻mesenchymal transition, and remodeling of the extracellular matrix. In this review, we describe the diverse roles of podoplanin in inflammation and cancer, depict the protein ligands of podoplanin identified so far, and discuss the mechanistic basis for the involvement of podoplanin in all these processes.
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11
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Hsp70 interactions with membrane lipids regulate cellular functions in health and disease. Prog Lipid Res 2019; 74:18-30. [PMID: 30710597 DOI: 10.1016/j.plipres.2019.01.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 01/18/2019] [Accepted: 01/28/2019] [Indexed: 02/07/2023]
Abstract
Beyond guarding the cellular proteome the major stress inducible heat shock protein Hsp70 has been shown to interact with lipids. Non-cytosolic Hsp70 stabilizes membranes during stress challenges and, in pathophysiological states, facilitates endocytosis, counteracts apoptotic mechanisms, sustains survival pathways or represents a signal that can be recognized by the immune system. Disease-coupled lipid-associated functions of Hsp70 may be targeted via distinct subcellular localizations of Hsp70 itself or its specific interacting lipids. With a special focus on interacting lipids, here we discuss localization-dependent roles of the membrane-bound Hsp70 in the context of its therapeutic potential, particularly in cancer and neurodegenerative diseases.
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12
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Kato Y, Yamada S, Itai S, Konnai S, Kobayashi A, Kaneko MK. Detection of Alpaca Podoplanin by Immunohistochemistry Using the Antibovine Podoplanin Monoclonal Antibody PMab-44. Monoclon Antib Immunodiagn Immunother 2018; 37:269-271. [PMID: 30570440 DOI: 10.1089/mab.2018.0037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Podoplanin (PDPN) is expressed in type I alveolar cells of the lungs, lymphatic endothelial cells, and podocytes of the kidneys, and induces platelet aggregation through the C-type lectin-like receptor-2. PDPNs of various animal species have been characterized using specific anti-PDPN monoclonal antibodies (mAbs). However, alpaca PDPN has not previously been characterized because antialpaca PDPN mAbs have not yet been developed. In this study, we investigated the potential cross-reaction between established antibovine PDPN mAbs and alpaca PDPN. Using immunohistochemical analysis, type I alveolar cells of the alpaca lungs were detected by the antibovine PDPN mAb, PMab-44. These results indicate that PMab-44 may be useful for the detection of alpaca PDPN.
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Affiliation(s)
- Yukinari Kato
- 1 Department of Antibody Drug Development, Tohoku University Graduate School of Medicine , Sendai, Japan .,2 New Industry Creation Hatchery Center, Tohoku University , Sendai, Japan
| | - Shinji Yamada
- 1 Department of Antibody Drug Development, Tohoku University Graduate School of Medicine , Sendai, Japan
| | - Shunsuke Itai
- 1 Department of Antibody Drug Development, Tohoku University Graduate School of Medicine , Sendai, Japan
| | - Satoru Konnai
- 3 Laboratory of Infectious Diseases, Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University , Sapporo, Japan .,4 Department of Advanced Pharmaceutics, Faculty of Veterinary Medicine, Hokkaido University , Sapporo, Japan
| | - Atsushi Kobayashi
- 5 Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University , Sapporo, Japan
| | - Mika K Kaneko
- 1 Department of Antibody Drug Development, Tohoku University Graduate School of Medicine , Sendai, Japan
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13
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Edkins AL, Price JT, Pockley AG, Blatch GL. Heat shock proteins as modulators and therapeutic targets of chronic disease: an integrated perspective. Philos Trans R Soc Lond B Biol Sci 2018; 373:rstb.2016.0521. [PMID: 29203706 DOI: 10.1098/rstb.2016.0521] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/17/2017] [Indexed: 02/07/2023] Open
Abstract
Many heat shock proteins (HSPs) are essential to survival as a consequence of their role as molecular chaperones, and play a critical role in maintaining cellular proteostasis by integrating the fundamental processes of protein folding and degradation. HSPs are arguably among the most prominent classes of proteins that have been broadly linked to many human disorders, with changes in their expression profile and/or intracellular/extracellular location now being described as contributing to the pathogenesis of a number of different diseases. Although the concept was initially controversial, it is now widely accepted that HSPs have additional biological functions over and above their role in proteostasis (so-called 'protein moonlighting'). Most importantly, these new insights are enlightening our understanding of biological processes in health and disease, and revealing novel and exciting therapeutic opportunities. This theme issue draws on therapeutic insights from established research on HSPs in cancer and other non-communicable disorders, with an emphasis on how the intracellular function of HSPs contrasts with their extracellular properties and function, and interrogates their potential diagnostic and therapeutic value to the prevention, management and treatment of chronic diseases.This article is part of the theme issue 'Heat shock proteins as modulators and therapeutic targets of chronic disease: an integrated perspective'.
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Affiliation(s)
- Adrienne L Edkins
- Biomedical Biotechnology Research Unit (BioBRU), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa
| | - John T Price
- Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, St Albans, Victoria, Australia.,Australian Institute for Musculoskeletal Science (AIMSS), Victoria University, University of Melbourne and Western Health, Melbourne, Victoria, Australia.,Department of Medicine, Melbourne Medical School-Western Precinct, University of Melbourne, St Albans, Victoria, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - A Graham Pockley
- John van Geest Cancer Research Centre, Nottingham Trent University, Clifton Campus, Clifton Lane, Nottingham, UK
| | - Gregory L Blatch
- Biomedical Biotechnology Research Unit (BioBRU), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa .,Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, St Albans, Victoria, Australia.,The Vice Chancellery, The University of Notre Dame Australia, Fremantle, Western Australia, Australia
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Unconventional Secretion of Heat Shock Proteins in Cancer. Int J Mol Sci 2017; 18:ijms18050946. [PMID: 28468249 PMCID: PMC5454859 DOI: 10.3390/ijms18050946] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 04/25/2017] [Accepted: 04/27/2017] [Indexed: 12/17/2022] Open
Abstract
Heat shock proteins (HSPs) are abundant cellular proteins involved with protein homeostasis. They have both constitutive and inducible isoforms, whose expression levels are further increased by stress conditions, such as temperature elevation, reduced oxygen levels, infection, inflammation and exposure to toxic substances. In these situations, HSPs exert a pivotal role in offering protection, preventing cell death and promoting cell recovery. Although the majority of HSPs functions are exerted in the cytoplasm and organelles, several lines of evidence reveal that HSPs are able to induce cell responses in the extracellular milieu. HSPs do not possess secretion signal peptides, and their secretion was subject to widespread skepticism until the demonstration of the role of unconventional secretion forms such as exosomes. Secretion of HSPs may confer immune system modulation and be a cell-to-cell mediated form of increasing stress resistance. Thus, there is a wide potential for secreted HSPs in resistance of cancer therapy and in the development new therapeutic strategies.
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Essa AAM, Yamazaki M, Maruyama S, Abé T, Babkair H, Raghib AM, Megahed EMED, Cheng J, Saku T. Tumour-associated macrophages are recruited and differentiated in the neoplastic stroma of oral squamous cell carcinoma. Pathology 2016; 48:219-27. [PMID: 27020496 DOI: 10.1016/j.pathol.2016.02.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Revised: 11/25/2015] [Accepted: 12/02/2015] [Indexed: 12/22/2022]
Abstract
To confirm our hypothesis that macrophages recruited to fight against oral squamous cell carcinoma (SCC) invasion are functionally differentiated within neoplastic stromata, we analysed arrangements of macrophage subtypes and cancer-associated fibroblasts (CAFs) in their association with blood vasculatures in the neoplastic stroma. Surgical specimens of oral SCC were immunohistochemically examined for macrophage phenotypes (CD68, CD163, and CD204) and stromal environments (perlecan, connexin 43, and CD31). Human monocytes were co-cultured with ZK-1 cells of oral SCC origin in different culture conditions. SCC stromata were divided into two types: fascicular (fibroblast-rich) and reticular (perlecan-rich). Regardless of stromal types, CD68 positive (+)/CD163+/CD204+ macrophages were recruited when blood vessels were abundant. Connexin 43+ fibroblasts were enriched in the fascicular stroma, where blood vessels were depleted. In co-culture experiments, monocytes, in the presence of ZK-1 cells, showed TNF-α(low)/IL-12(low) and IL-10(high)/VEGF(high)/MMP-9(high) with increased expression levels for fibronectin and perlecan. With direct contact with monocytes, SCC cells also expressed CD68 and CD163. SCC stromata were characterised by CD163+/CD204+ tumour-associated macrophages (TAMs) and connexin 43+ CAFs. TAMs are differentiated from monocytes by the physical contact with oral SCC cells in the perlecan-rich neoplastic stroma, which is also induced by the cross-talk between SCC cells and stromal cells including TAMs.
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Affiliation(s)
- Ahmed Abdelaziz Mohamed Essa
- Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; Department of Oral Pathology, Faculty of Dentistry, Tanta University, Tanta, Egypt
| | - Manabu Yamazaki
- Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Satoshi Maruyama
- Oral Pathology Section, Department of Surgical Pathology, Niigata University Hospital, Niigata, Japan
| | - Tatsuya Abé
- Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; Oral Pathology Section, Department of Surgical Pathology, Niigata University Hospital, Niigata, Japan
| | - Hamzah Babkair
- Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Adel Mohamed Raghib
- Department of Oral Pathology, Faculty of Dentistry, Tanta University, Tanta, Egypt
| | | | - Jun Cheng
- Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Takashi Saku
- Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; Oral Pathology Section, Department of Surgical Pathology, Niigata University Hospital, Niigata, Japan.
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Krishnan H, Retzbach EP, Ramirez MI, Liu T, Li H, Miller WT, Goldberg GS. PKA and CDK5 can phosphorylate specific serines on the intracellular domain of podoplanin (PDPN) to inhibit cell motility. Exp Cell Res 2015; 335:115-22. [PMID: 25959509 DOI: 10.1016/j.yexcr.2015.04.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 04/26/2015] [Accepted: 04/28/2015] [Indexed: 12/12/2022]
Abstract
Podoplanin (PDPN) is a transmembrane glycoprotein that promotes tumor cell migration, invasion, and cancer metastasis. In fact, PDPN expression is induced in many types of cancer. Thus, PDPN has emerged as a functionally relevant cancer biomarker and chemotherapeutic target. PDPN contains 2 intracellular serine residues that are conserved between species ranging from mouse to humans. Recent studies indicate that protein kinase A (PKA) can phosphorylate PDPN in order to inhibit cell migration. However, the number and identification of specific residues phosphorylated by PKA have not been defined. In addition, roles of other kinases that may phosphorylate PDPN to control cell migration have not been investigated. We report here that cyclin dependent kinase 5 (CDK5) can phosphorylate PDPN in addition to PKA. Moreover, results from this study indicate that PKA and CDK5 cooperate to phosphorylate PDPN on both intracellular serine residues to decrease cell motility. These results provide new insight into PDPN phosphorylation dynamics and the role of PDPN in cell motility. Understanding novel mechanisms of PDPN intracellular signaling could assist with designing novel targeted chemotherapeutic agents and procedures.
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Affiliation(s)
- Harini Krishnan
- Graduate School of Biomedical Sciences and Department of Molecular Biology, Rowan University School of Osteopathic Medicine, Science Center, 2 Medical Center Drive, Stratford, NJ 08084, USA
| | - Edward P Retzbach
- Graduate School of Biomedical Sciences and Department of Molecular Biology, Rowan University School of Osteopathic Medicine, Science Center, 2 Medical Center Drive, Stratford, NJ 08084, USA
| | - Maria I Ramirez
- Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Tong Liu
- Center for Advanced Proteomics Research and Department of Biochemistry and Molecular Biology, Rutgers New Jersey Medical School Cancer Center,205 S. Orange Avenue, F-1226, Newark, NJ 07103, USA
| | - Hong Li
- Center for Advanced Proteomics Research and Department of Biochemistry and Molecular Biology, Rutgers New Jersey Medical School Cancer Center,205 S. Orange Avenue, F-1226, Newark, NJ 07103, USA
| | - W Todd Miller
- Department of Physiology and Biophysics, Basic Science Tower T-5, Stony Brook University, Stony Brook, NY 11794-8661, USA
| | - Gary S Goldberg
- Graduate School of Biomedical Sciences and Department of Molecular Biology, Rowan University School of Osteopathic Medicine, Science Center, 2 Medical Center Drive, Stratford, NJ 08084, USA.
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Tsuneki M, Madri JA, Saku T. Cell–extracellular matrix interactions in oral tumorigenesis: Roles of podoplanin and CD44 and modulation of Hippo pathway. J Oral Biosci 2015. [DOI: 10.1016/j.job.2015.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Renart J, Carrasco-Ramírez P, Fernández-Muñoz B, Martín-Villar E, Montero L, Yurrita MM, Quintanilla M. New insights into the role of podoplanin in epithelial-mesenchymal transition. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 317:185-239. [PMID: 26008786 DOI: 10.1016/bs.ircmb.2015.01.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Podoplanin is a small mucin-like transmembrane protein expressed in several adult tissues and with an important role during embryogenesis. It is needed for the proper development of kidneys and lungs as well as accurate formation of the lymphatic vascular system. In addition, it is involved in the physiology of the immune system. A wide variety of tumors express podoplanin, both in the malignant cells and in the stroma. Although there are exceptions, the presence of podoplanin results in poor prognosis. The main consequence of forced podoplanin expression in established and tumor-derived cell lines is an increase in cell migration and, eventually, the triggering of an epithelial-mesenchymal transition, whereby cells acquire a fibroblastoid phenotype and increased motility. We will examine the current status of the role of podoplanin in the induction of epithelial-mesenchymal transition as well as the different interactions that lead to this program.
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Affiliation(s)
- Jaime Renart
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
| | | | | | - Ester Martín-Villar
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
| | - Lucía Montero
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
| | - María M Yurrita
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
| | - Miguel Quintanilla
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
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Graner MW, Lillehei KO, Katsanis E. Endoplasmic reticulum chaperones and their roles in the immunogenicity of cancer vaccines. Front Oncol 2015; 4:379. [PMID: 25610811 PMCID: PMC4285071 DOI: 10.3389/fonc.2014.00379] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 12/17/2014] [Indexed: 11/25/2022] Open
Abstract
The endoplasmic reticulum (ER) is a major site of passage for proteins en route to other organelles, to the cell surface, and to the extracellular space. It is also the transport route for peptides generated in the cytosol by the proteasome into the ER for loading onto major histocompatibility complex class I (MHC I) molecules for eventual antigen presentation at the cell surface. Chaperones within the ER are critical for many of these processes; however, outside the ER certain of those chaperones may play important and direct roles in immune responses. In some cases, particular ER chaperones have been utilized as vaccines against tumors or infectious disease pathogens when purified from tumor tissue or recombinantly generated and loaded with antigen. In other cases, the cell surface location of ER chaperones has implications for immune responses as well as possible tumor resistance. We have produced heat-shock protein/chaperone protein-based cancer vaccines called “chaperone-rich cell lysate” (CRCL) that are conglomerates of chaperones enriched from solid tumors by an isoelectric focusing technique. These preparations have been effective against numerous murine tumors, as well as in a canine with an advanced lung carcinoma treated with autologous CRCL. We also published extensive proteomic analyses of CRCL prepared from human surgically resected tumor samples. Of note, these preparations contained at least 10 ER chaperones and a number of other residents, along with many other chaperones/heat-shock proteins. Gene ontology and network analyses utilizing these proteins essentially recapitulate the antigen presentation pathways and interconnections. In conjunction with our current knowledge of cell surface/extracellular ER chaperones, these data collectively suggest that a systems-level view may provide insight into the potent immune stimulatory activities of CRCL with an emphasis on the roles of ER components in those processes.
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Affiliation(s)
- Michael W Graner
- Department of Neurosurgery, Anschutz Medical Campus, University of Colorado School of Medicine , Aurora, CO , USA
| | - Kevin O Lillehei
- Department of Neurosurgery, Anschutz Medical Campus, University of Colorado School of Medicine , Aurora, CO , USA
| | - Emmanuel Katsanis
- Department of Pediatrics, The University of Arizona , Tucson, AZ , USA
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Podoplanin-mediated cell adhesion through extracellular matrix in oral squamous cell carcinoma. J Transl Med 2013; 93:921-32. [PMID: 23817087 DOI: 10.1038/labinvest.2013.86] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 04/29/2013] [Accepted: 05/27/2013] [Indexed: 11/08/2022] Open
Abstract
Podoplanin (PDPN), one of the representative mucin-like type-I transmembrane glycoproteins specific to lymphatic endothelial cells, is expressed in various cancers including squamous cell carcinoma (SCC). On the basis of our previous studies, we have developed the hypothesis that PDPN functions in association with the extracellular matrix (ECM) from the cell surface side. The aim of this study was to elucidate the molecular role of PDPN in terms of cell adhesion, proliferation, and migration in oral SCC cells. Forty-four surgical specimens of oral SCC were used for immunohistochemistry for PDPN, and the expression profiles were correlated with their clinicopathological properties. Using ZK-1, a human oral SCC cell system, and five other cell systems, we examined PDPN expression levels by immunofluorescence, western blotting, and real-time PCR. The effects of transient PDPN knockdown by siRNA in ZK-1 were determined for cellular functions in terms of cell proliferation, adhesion, migration, and invasion in association with CD44 and hyaluronan. Cases without PDPN-positive cells were histopathologically classified as less-differentiated SCC, and SCC cells without PDPN more frequently invaded lymphatics. Adhesive properties of ZK-1 were significantly inhibited by siRNA, and PDPN was shown to collaborate with CD44 in cell adhesion to tether SCC cells with hyaluronan-rich ECM of the narrow intercellular space as well as with the stromal ECM. There was no siRNA effect in migration. We have demonstrated the primary function of PDPN in cell adhesion to ECM, which is to secondarily promote oral SCC cell proliferation.
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