1
|
Sarkar S. Recent advancements in bionanomaterial applications of peptide nucleic acid assemblies. Biopolymers 2024; 115:e23567. [PMID: 37792292 DOI: 10.1002/bip.23567] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/02/2023] [Accepted: 09/19/2023] [Indexed: 10/05/2023]
Abstract
Peptide nucleic acid (PNA) is a unique combination of peptides and nucleic acids. PNA can exhibit hydrogen bonding interactions with complementary nucleobases like DNA/RNA. Also, its polyamide backbone allows easy incorporation of biomolecules like peptides and proteins to build hybrid molecular constructs. Because of chimeric structural properties, PNA has lots of potential to build diverse nanostructures. However, progress in the PNA material field is still immature compared with its massive applications in antisense oligonucleotide research. Examples of well-defined molecular assemblies have been reported with PNA amphiphiles, self-assembling guanine-PNA monomers/dimers, and PNA-decorated nucleic acids/ polymers/ peptides. All these works indicate the great potential of PNA to be used as bionanomaterials. The review summarizes the recent reports on PNA-based nanostructures and their versatile applications. Additionally, this review shares a perspective to promote a better understanding of controlling molecular assembly by the systematic structural modifications of PNA monomers.
Collapse
Affiliation(s)
- Srijani Sarkar
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, Maryland, USA
| |
Collapse
|
2
|
Yi Y, Feng C, Yu M, Mei L, Wu M, Tao W. Peptide-based siRNA delivery system for tumor vascular normalization and gene silencing in 4T1 cells. STAR Protoc 2023; 4:102138. [PMID: 36861826 PMCID: PMC10011649 DOI: 10.1016/j.xpro.2023.102138] [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: 11/28/2022] [Revised: 01/04/2023] [Accepted: 02/06/2023] [Indexed: 03/03/2023] Open
Abstract
Efficient gene delivery in an integrated drug delivery system is urgent for multimodal antitumor therapy. Herein, we describe a protocol for constructing a peptide-based siRNA delivery system to achieve tumor vascular normalization and gene silencing in 4T1 cells. We highlighted four major steps, including (1) synthesis of the chimeric peptide, (2) preparation and characterization of PA7R@siRNA micelleplexes, (3) in vitro tube formation assay and transwell cell migration assay, and (4) siRNA transfection in 4T1 cells. This delivery system is expected to be used to silence gene expression, normalize tumor vasculature, and perform other treatments based on the different peptide segments. For complete details on the use and execution of this protocol, please refer to Yi et al. (2022).1.
Collapse
Affiliation(s)
- Yunfei Yi
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Chan Feng
- Center for Nanomedicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Respiratory Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Mian Yu
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Lin Mei
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China; Tianjin Key Laboratory of Biomedical Materials, Key Laboratory of Biomaterials and Nanotechnology for Cancer Immunotherapy, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300192, China
| | - Meiying Wu
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China.
| | - Wei Tao
- Center for Nanomedicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
3
|
Li G, Zhang Y, Li J. A hybrid nanoassembly for ultrasound-inducible cytosolic siRNA delivery and cancer sono-gene therapy. ULTRASONICS SONOCHEMISTRY 2023; 92:106262. [PMID: 36512940 PMCID: PMC9763732 DOI: 10.1016/j.ultsonch.2022.106262] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/02/2022] [Accepted: 12/06/2022] [Indexed: 05/10/2023]
Abstract
Cancer gene therapy by small-interfering RNAs (siRNAs) holds great promise but is impeded by a low cytoplasmic delivery efficiency. The past two decades have witnessed many efforts that are dedicated to discover biomaterials in order to increase cellular uptake efficiency of siRNAs. However, less attention has been paid to the lysosomal trapping dilemma that greatly restricts gene silencing outcomes. Herein, to address this challenge, we developed a sono-controllable strategy for ultrasound-promoted cytosolic siRNA delivery. A hybrid nanoassembly (HNA) was prepared via electrostatic self-assembly of a siRNA and a nona-arginine modified with protoporphyrin IX that is a sonosensitizer. After cellular uptake and exposure to sono-irradiation, HNA generated singlet oxygen to facilitate the lysosomal escape of siRNA to knock down anti-apoptotic Bcl-2 in the cytoplasm. We showed that the colocalization ratios between siRNA and the lysosome decreased from 91 % to 33 % post sono-irradiation; meanwhile, the gene silencing efficacy increased from 46 % to 68 % at 300 nM of HNA. Furthermore, sonodynamic therapy was achieved by the sonosensitizer under ultrasound irradiation, which combined gene therapy to eradicate cancer cells, resulting in a cell death rate of 82 %. This study thus presents a novel ultrasonic approach for effective cytoplasmic delivery of siRNAs and combinational sono-gene therapy of cancer.
Collapse
Affiliation(s)
- Gaigai Li
- State Key Laboratory of Analytical Chemistry for Life Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Chemistry and Biomedicine Innovation Center (ChemBIC), Nanjing University, Nanjing 210023, China
| | - Yan Zhang
- State Key Laboratory of Analytical Chemistry for Life Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Chemistry and Biomedicine Innovation Center (ChemBIC), Nanjing University, Nanjing 210023, China.
| | - Jinbo Li
- State Key Laboratory of Analytical Chemistry for Life Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Chemistry and Biomedicine Innovation Center (ChemBIC), Nanjing University, Nanjing 210023, China.
| |
Collapse
|
4
|
Noncoding RNAs Emerging as Drugs or Drug Targets: Their Chemical Modification, Bio-Conjugation and Intracellular Regulation. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27196717. [PMID: 36235253 PMCID: PMC9573214 DOI: 10.3390/molecules27196717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 10/06/2022] [Accepted: 10/07/2022] [Indexed: 11/07/2022]
Abstract
With the increasing understanding of various disease-related noncoding RNAs, ncRNAs are emerging as novel drugs and drug targets. Nucleic acid drugs based on different types of noncoding RNAs have been designed and tested. Chemical modification has been applied to noncoding RNAs such as siRNA or miRNA to increase the resistance to degradation with minimum influence on their biological function. Chemical biological methods have also been developed to regulate relevant noncoding RNAs in the occurrence of various diseases. New strategies such as designing ribonuclease targeting chimeras to degrade endogenous noncoding RNAs are emerging as promising approaches to regulate gene expressions, serving as next-generation drugs. This review summarized the current state of noncoding RNA-based theranostics, major chemical modifications of noncoding RNAs to develop nucleic acid drugs, conjugation of RNA with different functional biomolecules as well as design and screening of potential molecules to regulate the expression or activity of endogenous noncoding RNAs for drug development. Finally, strategies of improving the delivery of noncoding RNAs are discussed.
Collapse
|
5
|
Kwek G, Lingesh S, Chowdhury SZ, Xing B. Tumour enzyme affinity mediated peptide molecular crowding for targeted disruption of hyperactivated glucose uptake. Chem Commun (Camb) 2022; 58:1350-1353. [PMID: 34986211 DOI: 10.1039/d1cc06049j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
An unconventional environment-responsive molecular crowding via specific binding between small molecule peptide inhibitor derivatives and an overexpressed tumour enzyme has been developed. Assemblies of such short peptides selectively localize on tumour surfaces and exhibited unique functions in disrupting hyperactivated glucose uptake, providing novel insights towards strategic tumour treatment.
Collapse
Affiliation(s)
- Germain Kwek
- Division of Chemistry and Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, 21 Nanyang link, 637371, Singapore.
| | - Shonya Lingesh
- Division of Chemistry and Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, 21 Nanyang link, 637371, Singapore.
| | - Sayba Zafrin Chowdhury
- Division of Chemistry and Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, 21 Nanyang link, 637371, Singapore.
| | - Bengang Xing
- Division of Chemistry and Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, 21 Nanyang link, 637371, Singapore. .,School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore
| |
Collapse
|
6
|
Marras AE, Ting JM, Stevens KC, Tirrell MV. Advances in the Structural Design of Polyelectrolyte Complex Micelles. J Phys Chem B 2021; 125:7076-7089. [PMID: 34160221 PMCID: PMC9282648 DOI: 10.1021/acs.jpcb.1c01258] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Polyelectrolyte complex micelles (PCMs) are a unique class of self-assembled nanoparticles that form with a core of associated polycations and polyanions, microphase-separated from neutral, hydrophilic coronas in aqueous solution. The hydrated nature and structural and chemical versatility make PCMs an attractive system for delivery and for fundamental polymer physics research. By leveraging block copolymer design with controlled self-assembly, fundamental structure-property relationships can be established to tune the size, morphology, and stability of PCMs precisely in pursuit of tailored nanocarriers, ultimately offering storage, protection, transport, and delivery of active ingredients. This perspective highlights recent advances in predictive PCM design, focusing on (i) structure-property relationships to target specific nanoscale dimensions and shapes and (ii) characterization of PCM dynamics primarily using time-resolved scattering techniques. We present several vignettes from these two emerging areas of PCM research and discuss key opportunities for PCM design to advance precision medicine.
Collapse
Affiliation(s)
- Alexander E Marras
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
| | - Jeffrey M Ting
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
| | - Kaden C Stevens
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
| | - Matthew V Tirrell
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
| |
Collapse
|
7
|
Liang X, Liu M, Komiyama M. Recognition of Target Site in Various Forms of DNA and RNA by Peptide Nucleic Acid (PNA): From Fundamentals to Practical Applications. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20210086] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Xingguo Liang
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, P. R. China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266235, P. R. China
| | - Mengqin Liu
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, P. R. China
| | - Makoto Komiyama
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, P. R. China
| |
Collapse
|
8
|
miRNA-22 as a Candidate Diagnostic Biomarker for Coronary Slow Flow. Cardiol Res Pract 2020; 2020:7490942. [PMID: 32774915 PMCID: PMC7399758 DOI: 10.1155/2020/7490942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 06/17/2020] [Accepted: 07/04/2020] [Indexed: 12/20/2022] Open
Abstract
Background Coronary slow flow (CSF) refers to the phenomenon of delayed distal flow in the absence of lesions detected on coronary angiography. Although the detection rate of CSF has been increasing in clinical practice, early diagnosis is difficult and the factors contributing to this condition remain unclear. Given the increasing demonstration of the roles of microRNAs (miRNAs) in disease and as diagnostic biomarkers, the aim of this study was to analyze the expression of serum miRNA-22 in patients with CSF detected using coronary angiography and its diagnostic efficacy. Methods and Results A retrospective analysis including 44 patients with CSF and 42 patients with normal coronary flow (control group) was conducted. Additionally, all included patients either did not have visually estimated coronary artery stenosis or had <50% stenosis. Plasma samples were collected from patients in these two groups, and the levels of miRNA-22 were detected. The receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic efficiency of serum miRNA-22 in the context of CSF. Results The expression of serum miRNA-22 was significantly higher in the CSF patients than in the control subjects (P < 0.0001). The area under the ROC curve for miRNA-22 in diagnosing CSF was 0.8293 (95% confidence interval: 0.7313–0.9272), with a sensitivity of 75.0% and specificity of 88.1%. Conclusions The expression of serum miRNA-22 in CSF is upregulated compared to that in subjects with normal coronary flow and shows relatively high clinical diagnostic efficiency, suggesting a new potential biomarker for the early diagnosis of CSF.
Collapse
|
9
|
Bolz M, Thomas L, Scheffer U, Kalden E, Hartmann RK, Göbel MW. Redirection of miRNA-Argonaute Complexes to Specific Target Sites by Synthetic Adaptor Molecules. Chem Biodivers 2020; 17:e2000272. [PMID: 32428353 DOI: 10.1002/cbdv.202000272] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 05/19/2020] [Indexed: 12/28/2022]
Abstract
Dysregulation of miRNAs is connected with a multitude of diseases for which antagomirs and miRNA replacement are discussed as therapeutic options. Here, we suggest an alternative concept based on the redirection of RISCs to non-native target sites. Metabolically stable DNA-LNA mixmers are used to mediate the binding of RISCs to mRNAs without any direct base complementarity to the presented guide RNA strand. Physical redirection of a dye-labeled miRNA model and of specific miRNA-programmed RISC fractions present in HeLa extracts is demonstrated by pull-down experiments with biotinylated capture oligonucleotides.
Collapse
Affiliation(s)
- Mathias Bolz
- Institute of Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Max-von-Laue-Str. 7, DE-60438, Frankfurt, Germany
| | - Laura Thomas
- Institute of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6-10, DE-35032, Marburg, Germany
| | - Ute Scheffer
- Institute of Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Max-von-Laue-Str. 7, DE-60438, Frankfurt, Germany
| | - Elisabeth Kalden
- Institute of Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Max-von-Laue-Str. 7, DE-60438, Frankfurt, Germany
| | - Roland K Hartmann
- Institute of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6-10, DE-35032, Marburg, Germany
| | - Michael W Göbel
- Institute of Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Max-von-Laue-Str. 7, DE-60438, Frankfurt, Germany
| |
Collapse
|
10
|
microRNAs in the Antitumor Immune Response and in Bone Metastasis of Breast Cancer: From Biological Mechanisms to Therapeutics. Int J Mol Sci 2020; 21:ijms21082805. [PMID: 32316552 PMCID: PMC7216039 DOI: 10.3390/ijms21082805] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 04/03/2020] [Accepted: 04/15/2020] [Indexed: 12/11/2022] Open
Abstract
Breast cancer is the most common type of cancer in women, and the occurrence of metastasis drastically worsens the prognosis and reduces overall survival. Understanding the biological mechanisms that regulate the transformation of malignant cells, the consequent metastatic transformation, and the immune surveillance in the tumor progression would contribute to the development of more effective and targeted treatments. In this context, microRNAs (miRNAs) have proven to be key regulators of the tumor-immune cells crosstalk for the hijack of the immunosurveillance to promote tumor cells immune escape and cancer progression, as well as modulators of the metastasis formation process, ranging from the preparation of the metastatic site to the transformation into the migrating phenotype of tumor cells. In particular, their deregulated expression has been linked to the aberrant expression of oncogenes and tumor suppressor genes to promote tumorigenesis. This review aims at summarizing the role and functions of miRNAs involved in antitumor immune response and in the metastasis formation process in breast cancer. Additionally, miRNAs are promising targets for gene therapy as their modulation has the potential to support or inhibit specific mechanisms to negatively affect tumorigenesis. With this perspective, the most recent strategies developed for miRNA-based therapeutics are illustrated.
Collapse
|
11
|
Chen L, Sun Y, Li J, Zhang Y. A photoactivatable microRNA probe for identification of microRNA targets and light-controlled suppression of microRNA target expression. Chem Commun (Camb) 2019; 56:627-630. [PMID: 31833483 DOI: 10.1039/c9cc08277h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Here, we report a novel dual-functional microRNA (miRNA) probe, PA-miRNA, for miRNA target identification and light control of miRNA target expression. PA-miRNA is a miRNA mimic with a 3'-biotin tag linked via a photo-cleavable linker. Using PA-miR-34a, intracellular targets of miR-34a in HeLa cells were isolated and confirmed. Moreover, PA-miR-34a upon transfection into HeLa cells was inactive until light irradiation to break the photo-cleavable linker to release functional miR-34a. We demonstrated that miR-34a target expression as well as miR-34a-promoted cell apoptosis were regulated by PA-miR-34a in a photo-controllable manner.
Collapse
Affiliation(s)
- Lei Chen
- State Key Laboratory of Analytical Chemistry for Life Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Chemistry and Biomedicine Innovation Center, Nanjing University, Nanjing 210023, China.
| | - Yu Sun
- State Key Laboratory of Analytical Chemistry for Life Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Chemistry and Biomedicine Innovation Center, Nanjing University, Nanjing 210023, China.
| | - Jinbo Li
- State Key Laboratory of Analytical Chemistry for Life Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Chemistry and Biomedicine Innovation Center, Nanjing University, Nanjing 210023, China.
| | - Yan Zhang
- State Key Laboratory of Analytical Chemistry for Life Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Chemistry and Biomedicine Innovation Center, Nanjing University, Nanjing 210023, China.
| |
Collapse
|
12
|
To KKW, Fong W, Tong CWS, Wu M, Yan W, Cho WCS. Advances in the discovery of microRNA-based anticancer therapeutics: latest tools and developments. Expert Opin Drug Discov 2019; 15:63-83. [PMID: 31739699 DOI: 10.1080/17460441.2020.1690449] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Introduction: MicroRNAs (miRNAs) are small endogenous non-coding RNAs that repress the expression of their target genes by reducing mRNA stability and/or inhibiting translation. miRNAs are known to be aberrantly regulated in cancers. Modulators of miRNA (mimics and antagonists) have emerged as novel therapeutic tools for cancer treatment.Areas covered: This review summarizes the various strategies that have been applied to correct the dysregulated miRNA in cancer cells. The authors also discuss the recent advances in the technical development and preclinical/clinical evaluation of miRNA-based therapeutic agents.Expert opinion: Application of miRNA-based therapeutics for cancer treatment is appealing because they are able to modulate multiple dysregulated genes and/or signaling pathways in cancer cells. Major obstacles hindering their clinical development include drug delivery, off-target effects, efficacious dose determination, and safety. Tumor site-specific delivery of novel miRNA therapeutics may help to minimize off-target effects and toxicity. Combination of miRNA therapeutics with other anticancer treatment modalities could provide a synergistic effect, thus allowing the use of lower dose, minimizing off-target effects, and improving the overall safety profile in cancer patients. It is critical to identify individual miRNAs with cancer type-specific and context-specific regulation of oncogenes and tumor-suppressor genes in order to facilitate the precise use of miRNA anticancer therapeutics.
Collapse
Affiliation(s)
- Kenneth K W To
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Winnie Fong
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Christy W S Tong
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Mingxia Wu
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Wei Yan
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - William C S Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong SAR, China
| |
Collapse
|