1
|
Wang YF, Shen ZF, Xiang FY, Wang H, Zhang P, Zhang Q. The direct transfer approach for transcellular drug delivery. Drug Deliv 2023; 30:2288799. [PMID: 38037327 PMCID: PMC10987047 DOI: 10.1080/10717544.2023.2288799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 11/12/2023] [Indexed: 12/02/2023] Open
Abstract
A promising paradigm for drug administration that has garnered increasing attention in recent years is the direct transfer (DT) of nanoparticles for transcellular drug delivery. DT requires direct cell-cell contact and facilitates unidirectional and bidirectional matter exchange between neighboring cells. Consequently, DT enables fast and deep penetration of drugs into the targeted tissues. This comprehensive review discusses the direct transfer concept, which can be delineated into the following three distinct modalities: membrane contact-direct transfer, gap junction-mediated direct transfer (GJ-DT), and tunneling nanotubes-mediated direct transfer (TNTs-DT). Further, the intercellular structures for each modality of direct transfer and their respective merits and demerits are summarized. The review also discusses the recent progress on the drugs or drug delivery systems that could activate DT.
Collapse
Affiliation(s)
- Yi-Fan Wang
- Graduate Department, Bengbu Medical College, Bengbu, Anhui, China
- Urology & Nephrology Center, Department of Urology, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Ze-Fan Shen
- Urology & Nephrology Center, Department of Urology, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Fang-yue Xiang
- School of Stomatology, Zhejiang Chinese Medical University, Hangzhou, China
| | - Heng Wang
- Urology & Nephrology Center, Department of Urology, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Pu Zhang
- Urology & Nephrology Center, Department of Urology, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Qi Zhang
- Graduate Department, Bengbu Medical College, Bengbu, Anhui, China
- Urology & Nephrology Center, Department of Urology, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| |
Collapse
|
2
|
Ramírez-Jarquín UN, Sharma M, Shahani N, Li Y, Boregowda S, Subramaniam S. Rhes protein transits from neuron to neuron and facilitates mutant huntingtin spreading in the brain. SCIENCE ADVANCES 2022; 8:eabm3877. [PMID: 35319973 PMCID: PMC8942366 DOI: 10.1126/sciadv.abm3877] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 02/02/2022] [Indexed: 05/12/2023]
Abstract
Rhes (RASD2) is a thyroid hormone-induced gene that regulates striatal motor activity and promotes neurodegeneration in Huntington disease (HD) and tauopathy. Rhes moves and transports the HD protein, polyglutamine-expanded huntingtin (mHTT), via tunneling nanotube (TNT)-like membranous protrusions between cultured neurons. However, similar intercellular Rhes transportation in the intact brain was unknown. Here, we report that Rhes induces TNT-like protrusions in the striatal medium spiny neurons (MSNs) and transported between dopamine-1 receptor (D1R)-MSNs and D2R-MSNs of intact striatum and organotypic brain slices. Notably, mHTT is robustly transported within the striatum and from the striatum to the cortical areas in the brain, and Rhes deletion diminishes such transport. Moreover, Rhes moves to the cortical regions following restricted expression in the MSNs of the striatum. Thus, Rhes is a first striatum-enriched protein demonstrated to move and transport mHTT between neurons and brain regions, providing new insights into interneuronal protein transport in the brain.
Collapse
Affiliation(s)
| | - Manish Sharma
- Department of Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Neelam Shahani
- Department of Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Yuqing Li
- Department of Neurology, University of Florida, Gainesville, FL 32610, USA
| | - Siddaraju Boregowda
- Department of Molecular Medicine, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Srinivasa Subramaniam
- Department of Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| |
Collapse
|
3
|
Murray LMA, Krasnodembskaya AD. Concise Review: Intercellular Communication Via Organelle Transfer in the Biology and Therapeutic Applications of Stem Cells. Stem Cells 2018; 37:14-25. [PMID: 30353966 DOI: 10.1002/stem.2922] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 09/14/2018] [Accepted: 09/22/2018] [Indexed: 12/13/2022]
Abstract
The therapeutic potential of stem cell-based therapies may be largely dependent on the ability of stem cells to modulate host cells rather than on their differentiation into host tissues. Within the last decade, there has been considerable interest in the intercellular communication mediated by the transfer of cytoplasmic material and organelles between cells. Numerous studies have shown that mitochondria and lysosomes are transported between cells by various mechanisms, such as tunneling nanotubes, microvesicles, and cellular fusion. This review will focus on the known instances of organelle transfer between stem cells and differentiated cells, what effects it has on recipient cells and how organelle transfer is regulated. Stem Cells 2019;37:14-25.
Collapse
Affiliation(s)
- Lisa M A Murray
- Centre for Experimental Medicine, School of Medicine Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom
| | - Anna D Krasnodembskaya
- Centre for Experimental Medicine, School of Medicine Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom
| |
Collapse
|
4
|
Tang BL. The use of mesenchymal stem cells (MSCs) for amyotrophic lateral sclerosis (ALS) therapy – a perspective on cell biological mechanisms. Rev Neurosci 2017; 28:725-738. [DOI: 10.1515/revneuro-2017-0018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 04/04/2017] [Indexed: 12/12/2022]
Abstract
AbstractRecent clinical trials of mesenchymal stem cells (MSCs) transplantation have demonstrated procedural safety and clinical proof of principle with a modest indication of benefit in patients with amyotrophic lateral sclerosis (ALS). While replacement therapy remained unrealistic, the clinical efficacy of this therapeutic option could be potentially enhanced if we could better decipher the mechanisms underlying some of the beneficial effects of transplanted cells, and work toward augmenting or combining these in a strategic manner. Novel ways whereby MSCs could act in modifying disease progression should also be explored. In this review, I discuss the known, emerging and postulated mechanisms of action underlying effects that transplanted MSCs may exert to promote motor neuron survival and/or to encourage regeneration in ALS. I shall also speculate on how transplanted cells may alter the diseased environment so as to minimize non-neuron cell autonomous damages by immune cells and astrocytes.
Collapse
Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University Health System, Singapore
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Medical Drive, Singapore 117597, Singapore
| |
Collapse
|
5
|
Winnard PT, Zhang C, Vesuna F, Kang JW, Garry J, Dasari RR, Barman I, Raman V. Organ-specific isogenic metastatic breast cancer cell lines exhibit distinct Raman spectral signatures and metabolomes. Oncotarget 2017; 8:20266-20287. [PMID: 28145887 PMCID: PMC5386761 DOI: 10.18632/oncotarget.14865] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 01/17/2017] [Indexed: 12/13/2022] Open
Abstract
Molecular characterization of organ-specific metastatic lesions, which distinguish them from the primary tumor, will provide a better understanding of tissue specific adaptations that regulate metastatic progression. Using an orthotopic xenograft model, we have isolated isogenic metastatic human breast cancer cell lines directly from organ explants that are phenotypically distinct from the primary tumor cell line. Label-free Raman spectroscopy was used and informative spectral bands were ascertained as differentiators of organ-specific metastases as opposed to the presence of a single universal marker. Decision algorithms derived from the Raman spectra unambiguously identified these isogenic cell lines as unique biological entities – a finding reinforced through metabolomic analyses that indicated tissue of origin metabolite distinctions between the cell lines. Notably, complementarity of the metabolomics and Raman datasets was found. Our findings provide evidence that metastatic spread generates tissue-specific adaptations at the molecular level within cancer cells, which can be differentiated with Raman spectroscopy.
Collapse
Affiliation(s)
- Paul T Winnard
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Chi Zhang
- The Johns Hopkins University, Department of Mechanical Engineering, Whiting School of Engineering, Baltimore, MD 21218, USA
| | - Farhad Vesuna
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jeon Woong Kang
- Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jonah Garry
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ramachandra Rao Dasari
- Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ishan Barman
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,The Johns Hopkins University, Department of Mechanical Engineering, Whiting School of Engineering, Baltimore, MD 21218, USA
| | - Venu Raman
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Pathology, University Medical Center Utrecht Cancer Center, 3508 GA Utrecht, The Netherlands
| |
Collapse
|
6
|
Johnson SM, Dempsey C, Parker C, Mironov A, Bradley H, Saha V. Acute lymphoblastic leukaemia cells produce large extracellular vesicles containing organelles and an active cytoskeleton. J Extracell Vesicles 2017; 6:1294339. [PMID: 28386390 PMCID: PMC5373679 DOI: 10.1080/20013078.2017.1294339] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 01/26/2016] [Indexed: 02/07/2023] Open
Abstract
Extracellular vesicles have been described in non-paracrine cellular interactions in cancer. We report a similar phenomenon in B-cell precursor (BCP) acute lymphoblastic leukaemia (ALL). Using advanced microscopy and high throughput screening, we further characterise a subset of large vesicles (LEVs) identified in cell lines, murine models of human BCP-ALL and clinical samples. Primary ALL blasts and cell lines released heterogeneous anucleate vesicles <6 micron into extracellular fluids. Larger LEVs were enclosed in continuous membranes, contained intact organelles and demonstrated an organised cytoskeleton. An excess of circulating CD19-positive LEVs were observed in diagnostic samples and isolated from mice engrafted with BCP-ALL primary cells. LEVs exhibited dynamic shape change in vitro and were internalised by other leukaemic cell lines leading to phenotypic transformation analogous to the cell of origin. In patient-derived xenografts, LEVs were released by primary ALL cells into extracellular spaces and internalised by murine mesenchymal cells in vivo. Collectively these data highlight the heterogeneity but accessibility of LEVs in clinical samples and their potential to provide a unique insight into the biology of the cell of origin and to their development as novel biomarkers to aid diagnosis and improve therapeutic outcomes.
Collapse
Affiliation(s)
- Suzanne M Johnson
- Children's Cancer Group, Division of Molecular and Clinical Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , UK
| | - Clare Dempsey
- Children's Cancer Group, Division of Molecular and Clinical Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , UK
| | - Catriona Parker
- Children's Cancer Group, Division of Molecular and Clinical Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , UK
| | - Aleksandr Mironov
- Children's Cancer Group, Division of Molecular and Clinical Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , UK
| | - Helen Bradley
- Faculty of Biology, Medicine and Health, CRUK Manchester Institute, University of Manchester , Manchester , UK
| | - Vaskar Saha
- Children's Cancer Group, Division of Molecular and Clinical Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK; Tata Translational Cancer Research Centre, Tata Medical Center, Kolkata, India
| |
Collapse
|
7
|
Lin HP, Zheng DJ, Li YP, Wang N, Chen SJ, Fu YC, Xu WC, Wei CJ. Incorporation of VSV-G produces fusogenic plasma membrane vesicles capable of efficient transfer of bioactive macromolecules and mitochondria. Biomed Microdevices 2016; 18:41. [PMID: 27165101 DOI: 10.1007/s10544-016-0066-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The objective of this study was to determine if plasma membrane vesicles (PMVs) could be exploited for efficient transfer of macro-biomolecules and mitochondria. PMVs were derived from mechanical extrusion, and made fusogenic (fPMVs) by incorporating the glycoprotein G of vesicular stomatitis virus (VSV-G). Confocal microscopy examination revealed that cytoplasmic proteins and mitochondria were enclosed in PMVs as evidenced by tracing with cytoplasmically localized and mitochondria-targeted EGFP, respectively. However, no fluorescence signal was detected in PMVs from cells whose nucleus was labeled with an EGFP-tagged histone H2B. Consistently, qRT-PCR measurement showed that mRNA, miRNA and mitochondrial DNA decreased slightly; while nuclear DNA was not measureable. Further, Western blot analysis revealed that cytoplasmic and membrane-bound proteins fell inconspicuously while nuclear proteins were barely detecsle. In addition, fPMVs carrying cytoplamic DsRed proteins transduced about ~40 % of recipient cells. The transfer of protein was further confirmed by using the inducible Cre/loxP system. Mitochondria transfer was found in about 20 % recipient cells after incubation with fPMVs for 5 h. To verify the functionalities of transferred mitochondria, mitochodria-deficient HeLa cells (Rho0) were generated and cultivated with fPMVs. Cell enumeration demonstrated that adding fPMVs into culture media stimulated Rho0 cell growth by 100 % as compared to the control. Lastly, MitoTracker and JC-1 staining showed that transferred mitochondria maintained normal shape and membrane potential in Rho0 cells. This study established a time-saving and efficient approach to delivering proteins and mitochondria by using fPMVs, which would be helpful for finding a cure to mitochondria-associated diseases. Graphical abstract Schematic of the delivery of macro-biomolecules and organelles by fPMVs. VSV-G-expressing cells were extruded through a 3 μm polycarbonate membrane filter to generate fusogenic plasma membrane vesicles (fPMVs), which contain bioactive molecules and organelles but not the nucleus. fPMVs can be endocytosed by target cells, while the cargo is released due to low-pH induced membrane fusion. These nucleus-free fPMVs are efficient at delivery of cytoplasmic proteins and mitochondria, leading to recovery of mitochondrial biogenesis and proliferative ability in mitochondria-deficient cells.
Collapse
Affiliation(s)
- Hao-Peng Lin
- Multidisciplinary Research Center, Shantou University, Shantou, Guangdong, 515063, China
| | - De-Jin Zheng
- Multidisciplinary Research Center, Shantou University, Shantou, Guangdong, 515063, China
| | - Yun-Pan Li
- Multidisciplinary Research Center, Shantou University, Shantou, Guangdong, 515063, China
| | - Na Wang
- Multidisciplinary Research Center, Shantou University, Shantou, Guangdong, 515063, China
| | - Shao-Jun Chen
- Multidisciplinary Research Center, Shantou University, Shantou, Guangdong, 515063, China
| | - Yu-Cai Fu
- Laboratory of Cell Senescence, Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Wen-Can Xu
- Department of Endocrinology, First Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Chi-Ju Wei
- Multidisciplinary Research Center, Shantou University, Shantou, Guangdong, 515063, China.
| |
Collapse
|
8
|
Yang H, Borg TK, Ma Z, Xu M, Wetzel G, Saraf LV, Markwald R, Runyan RB, Gao BZ. Biochip-based study of unidirectional mitochondrial transfer from stem cells to myocytes via tunneling nanotubes. Biofabrication 2016; 8:015012. [PMID: 26844857 DOI: 10.1088/1758-5090/8/1/015012] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Tunneling nanotubes (TNTs) are small membranous tubes of 50-1000 nm diameter observed to connect cells in culture. Transfer of subcellular organelles through TNTs was observed in vitro and in vivo, but the formation and significance of these structures is not well understood. A polydimethylsiloxane biochip-based coculture model was devised to constrain TNT orientation and explore both TNT-formation and TNT-mediated mitochondrial transfer. Two parallel microfluidic channels connected by an array of smaller microchannels enabled localization of stem cell and cardiomyocyte populations while allowing connections to form between them. Stem cells and cardiomyocytes were deposited in their respective microfluidic channels, and stem cell-cardiomyocyte pairs were formed via the microchannels. Formation of TNTs and transfer of stained mitochondria through TNTs was observed by 24 h real-time video recording. The data show that stem cells are 7.7 times more likely to initiate contact by initial extension of filopodia. By 24 h, 67% of nanotube connections through the microchannels are composed of cardiomyocyte membrane. Filopodial extension and retraction by stem cells draws an extension of TNTs from cardiomyocytes. MitoTracker staining shows that unidirectional transfer of mitochondria between stem cell-cardiomyocyte pairs invariably originates from stem cells. Control experiments with cardiac fibroblasts and cardiomyocytes show little nanotube formation between homotypic or mixed cell pairs and no mitochondrial transfer. These data identify a novel biological process, unidirectional mitochondrial transfer, mediated by heterotypic TNT connections. This suggests that the enhancement of cardiomyocyte function seen after stem-cell injection may be due to a bioenergetic stimulus provided by mitochondrial transfer.
Collapse
Affiliation(s)
- Huaxiao Yang
- Department of Bioengineering, Clemson University, Clemson, South Carolina, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Tang BL. MIRO GTPases in Mitochondrial Transport, Homeostasis and Pathology. Cells 2015; 5:cells5010001. [PMID: 26729171 PMCID: PMC4810086 DOI: 10.3390/cells5010001] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 12/22/2015] [Accepted: 12/24/2015] [Indexed: 01/08/2023] Open
Abstract
The evolutionarily-conserved mitochondrial Rho (MIRO) small GTPase is a Ras superfamily member with three unique features. It has two GTPase domains instead of the one found in other small GTPases, and it also has two EF hand calcium binding domains, which allow Ca2+-dependent modulation of its activity and functions. Importantly, it is specifically associated with the mitochondria and via a hydrophobic transmembrane domain, rather than a lipid-based anchor more commonly found in other small GTPases. At the mitochondria, MIRO regulates mitochondrial homeostasis and turnover. In metazoans, MIRO regulates mitochondrial transport and organization at cellular extensions, such as axons, and, in some cases, intercellular transport of the organelle through tunneling nanotubes. Recent findings have revealed a myriad of molecules that are associated with MIRO, particularly the kinesin adaptor Milton/TRAK, mitofusin, PINK1 and Parkin, as well as the endoplasmic reticulum-mitochondria encounter structure (ERMES) complex. The mechanistic aspects of the roles of MIRO and its interactors in mitochondrial homeostasis and transport are gradually being revealed. On the other hand, MIRO is also increasingly associated with neurodegenerative diseases that have roots in mitochondrial dysfunction. In this review, I discuss what is currently known about the cellular physiology and pathophysiology of MIRO functions.
Collapse
Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, MD7, 8 Medical Drive, Singapore 117597, Singapore.
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, 28 Medical Drive, Singapore 117456, Singapore.
| |
Collapse
|
10
|
Tang BL. Synthetic mitochondria as therapeutics against systemic aging: a hypothesis. Cell Biol Int 2014; 39:131-5. [DOI: 10.1002/cbin.10362] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Accepted: 07/26/2014] [Indexed: 12/31/2022]
Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry; Yong Loo Lin School of Medicine; National University Health System; Singapore
- NUS Graduate School for Integrative Sciences and Engineering; National University of Singapore; Medical Drive 117597 Singapore
| |
Collapse
|
11
|
Sun X, Wang Y, Zhang J, Tu J, Wang XJ, Su XD, Wang L, Zhang Y. Tunneling-nanotube direction determination in neurons and astrocytes. Cell Death Dis 2012; 3:e438. [PMID: 23222508 PMCID: PMC3542613 DOI: 10.1038/cddis.2012.177] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A tunneling nanotube (TNT) is a newly discovered structure involved in cell-cell communication and is found in various types of cells. Here we identify S100A4 as an extracellular molecule and describe its role in attracting the growth direction of TNTs. Together with its putative receptor, receptor for advanced glycation end product, we demonstrate their involvement in TNT direction guidance. Our results further suggest a mechanism for direction guidance of TNTs. In TNT-initiating cells, p53 activates caspase-3, which leads to S100A4 cleavage and its subsequent decrease in cellular concentration. The decrease in cellular S100A4 induces the formation of a gradient of S100A4, from a low concentration in initiating cells toward a high concentration in target cells. This concentration gradient of S100A4 induces direction guidance for TNTs.
Collapse
Affiliation(s)
- X Sun
- State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, Peking University, Beijing 100871, China
| | | | | | | | | | | | | | | |
Collapse
|