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Kuznetsov M, Adhikarla V, Caserta E, Wang X, Shively JE, Pichiorri F, Rockne RC. Mathematical Modeling Unveils Optimization Strategies for Targeted Radionuclide Therapy of Blood Cancers. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.22.595377. [PMID: 38826403 PMCID: PMC11142146 DOI: 10.1101/2024.05.22.595377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Targeted radionuclide therapy is based on injections of cancer-specific molecules conjugated with radioactive nuclides. Despite the specificity of this treatment, it is not devoid of side-effects limiting its use and is especially harmful for rapidly proliferating organs well perfused by blood, like bone marrow. Optimization of radioconjugates administration accounting for toxicity constraints can increase treatment efficacy. Based on our experiments on disseminated multiple myeloma mouse model treated by 225Ac-DOTA-daratumumab, we developed a mathematical model which investigation highlighted the following principles for optimization of targeted radionuclide therapy. 1) Nuclide to antibody ratio importance. The density of radioconjugates on cancer cells determines the density of radiation energy deposited in them. Low labeling ratio as well as accumulation of unlabeled antibodies and antibodies attached to decay products in the bloodstream can mitigate cancer radiation damage due to excessive occupation of specific receptors by antibodies devoid of radioactive nuclides. 2) Cancer binding capacity-based dosing. The rate of binding of drug to cancer cells depends on the total number of their specific receptors, which therefore can be estimated from the pharmacokinetic curve of diagnostic radioconjugates. Injection of doses significantly exceeding cancer binding capacity should be avoided since radioconjugates remaining in the bloodstream have negligible efficacy to toxicity ratio. 3) Particle range-guided multi-dosing. The use of short-range particle emitters and high-affinity antibodies allows for robust treatment optimization via initial saturation of cancer binding capacity, enabling redistribution of further injected radioconjugates and deposited dose towards still viable cells that continue expressing specific receptors.
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Affiliation(s)
- Maxim Kuznetsov
- Department of Computational and Quantitative Medicine, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA, United States
| | - Vikram Adhikarla
- Department of Computational and Quantitative Medicine, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA, United States
| | - Enrico Caserta
- Department of Hematologic Malignancies Translational Science, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA, United States
| | - Xiuli Wang
- Department of Hematology and Hematopoietic Cell Transplantation, City of Hope National Medical Center, Duarte, California, United States
| | - John E Shively
- Department of Molecular Imaging & Therapy, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States
| | - Flavia Pichiorri
- Department of Hematologic Malignancies Translational Science, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA, United States
| | - Russell C Rockne
- Department of Computational and Quantitative Medicine, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA, United States
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Qin S, Yang Y, Zhang J, Yin Y, Liu W, Zhang H, Fan X, Yang M, Yu F. Effective Treatment of SSTR2-Positive Small Cell Lung Cancer Using 211At-Containing Targeted α-Particle Therapy Agent Which Promotes Endogenous Antitumor Immune Response. Mol Pharm 2023; 20:5543-5553. [PMID: 37788300 PMCID: PMC10630944 DOI: 10.1021/acs.molpharmaceut.3c00427] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/15/2023] [Accepted: 09/15/2023] [Indexed: 10/05/2023]
Abstract
Small cell lung cancer (SCLC) is a neuroendocrine tumor with a high degree of malignancy. Due to limited treatment options, patients with SCLC have a poor prognosis. We have found, however, that intravenously administered octreotide (Oct) armed with astatine-211 ([211At]SAB-Oct) is effective against a somatostatin receptor 2 (SSTR2)-positive SCLC tumor in SCLC tumor-bearing BALB/c nude mice. In biodistribution analysis, [211At]SAB-Oct achieved the highest concentration in the SCLC tumors up to 3 h after injection as time proceeded. A single intravenous injection of [211At]SAB-Oct (370 kBq) was sufficient to suppress SSTR2-positive SCLC tumor growth in treated mice by inducing DNA double-strand breaks. Additionally, a multitreatment course (370 kBq followed by twice doses of 370 kBq for a total of 1110 kBq) inhibited the growth of the tumor compared to the untreated control group without significant off-target toxicity. Surprisingly, we found that [211At]SAB-Oct could up-regulate the expressions of calreticulin and major histocompatibility complex I (MHC-I) on the tumor cell membrane surface, suggesting that α-particle internal irradiation may activate an endogenous antitumor immune response through the regulation of immune cells in the tumor microenvironment, which could synergically enhance the efficacy of immunotherapy. We conclude that [211At]SAB-Oct is a potential new therapeutic option for SSTR2-positive SCLC.
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Affiliation(s)
- Shanshan Qin
- Department
of Nuclear Medicine, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, No. 301 Yan-chang-zhong Road, Shanghai 200072, People’s Republic of China
- Institute
of Nuclear Medicine, Tongji University School
of Medicine, No. 301
Yan-chang-zhong Road, Shanghai 200072, People’s Republic
of China
| | - Yuanyou Yang
- Key
Laboratory of Radiation Physics and Technology, Ministry of Education,
Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, People’s
Republic of China
| | - Jiajia Zhang
- Department
of Nuclear Medicine, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, No. 301 Yan-chang-zhong Road, Shanghai 200072, People’s Republic of China
- Institute
of Nuclear Medicine, Tongji University School
of Medicine, No. 301
Yan-chang-zhong Road, Shanghai 200072, People’s Republic
of China
| | - Yuzhen Yin
- Department
of Nuclear Medicine, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, No. 301 Yan-chang-zhong Road, Shanghai 200072, People’s Republic of China
- Institute
of Nuclear Medicine, Tongji University School
of Medicine, No. 301
Yan-chang-zhong Road, Shanghai 200072, People’s Republic
of China
| | - Weihao Liu
- Key
Laboratory of Radiation Physics and Technology, Ministry of Education,
Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, People’s
Republic of China
| | - Han Zhang
- Department
of Nuclear Medicine, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, No. 301 Yan-chang-zhong Road, Shanghai 200072, People’s Republic of China
- Institute
of Nuclear Medicine, Tongji University School
of Medicine, No. 301
Yan-chang-zhong Road, Shanghai 200072, People’s Republic
of China
| | - Xin Fan
- Department
of Nuclear Medicine, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, No. 301 Yan-chang-zhong Road, Shanghai 200072, People’s Republic of China
- Institute
of Nuclear Medicine, Tongji University School
of Medicine, No. 301
Yan-chang-zhong Road, Shanghai 200072, People’s Republic
of China
| | - Mengdie Yang
- Department
of Nuclear Medicine, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, No. 301 Yan-chang-zhong Road, Shanghai 200072, People’s Republic of China
- Institute
of Nuclear Medicine, Tongji University School
of Medicine, No. 301
Yan-chang-zhong Road, Shanghai 200072, People’s Republic
of China
| | - Fei Yu
- Department
of Nuclear Medicine, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, No. 301 Yan-chang-zhong Road, Shanghai 200072, People’s Republic of China
- Institute
of Nuclear Medicine, Tongji University School
of Medicine, No. 301
Yan-chang-zhong Road, Shanghai 200072, People’s Republic
of China
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Gnesin S, Chouin N, Cherel M, Dunn SM, Schaefer N, Faivre-Chauvet A, Prior JO, Delage JA. From bench to bedside: 64Cu/ 177Lu 1C1m-Fc anti TEM-1: mice-to-human dosimetry extrapolations for future theranostic applications. EJNMMI Res 2023; 13:59. [PMID: 37314509 DOI: 10.1186/s13550-023-01010-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 06/06/2023] [Indexed: 06/15/2023] Open
Abstract
The development of diagnostic and therapeutic radiopharmaceuticals is an hot topic in nuclear medicine. Several radiolabeled antibodies are under development necessitating both biokinetic and dosimetry extrapolations for effective human translation. The validation of different animal-to-human dosimetry extrapolation methods still is an open issue. This study reports the mice-to-human dosimetry extrapolation of 64Cu/177Lu 1C1m-Fc anti-TEM-1 for theranostic application in soft-tissue sarcomas. We adopt four methods; direct mice-to-human extrapolation (M1); dosimetry extrapolation considering a relative mass scaling factor (M2), application of a metabolic scaling factor (M3) and combination of M2 and M3 (M4). Predicted in-human dosimetry for the [64Cu]Cu-1C1m-Fc resulted in an effective dose of 0.05 mSv/MBq. Absorbed dose (AD) extrapolation for the [177Lu]Lu-1C1m-Fc indicated that the AD of 2 Gy and 4 Gy to the red-marrow and total-body can be reached with 5-10 GBq and 25-30 GBq of therapeutic activity administration respectively depending on applied dosimetry method. Dosimetry extrapolation methods provided significantly different absorbed doses in organs. Dosimetry properties for the [64Cu]Cu-1C1m-Fc are suitable for a diagnostic in-human use. The therapeutic application of [177Lu]Lu-1C1m-Fc presents challenges and would benefit from further assessments in animals' models such as dogs before moving into the clinic.
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Affiliation(s)
- Silvano Gnesin
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, 1011, Lausanne, Switzerland
| | - Nicolas Chouin
- Inserm, CNRS, University of Angers, Oniris, CRCI2NA, University of Nantes, Nantes, France
| | - Michel Cherel
- CHU Nantes, CNRS, Inserm, CRCINA, University of Nantes, 44000, Nantes, France
| | - Steven Mark Dunn
- LAbCore, Ludwig Institute for Cancer Research, Lausanne University Hospital and University of Lausanne, 1066, Epalinges, Switzerland
| | - Niklaus Schaefer
- Department of Nuclear Medicine and Molecular Imaging, Lausanne University Hospital and University of Lausanne, Rue du Bugnon 46, 1011, Lausanne, Switzerland
| | | | - John O Prior
- Department of Nuclear Medicine and Molecular Imaging, Lausanne University Hospital and University of Lausanne, Rue du Bugnon 46, 1011, Lausanne, Switzerland.
| | - Judith Anna Delage
- Radiopharmacy Unit, Department of Pharmacy, Lausanne University Hospital and University of Lausanne, 1011, Lausanne, Switzerland
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Tronchin S, Forster JC, Hickson K, Bezak E. Dosimetry in targeted alpha therapy. A systematic review: current findings and what is needed. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac5fe0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 03/22/2022] [Indexed: 12/13/2022]
Abstract
Abstract
Objective. A systematic review of dosimetry in Targeted Alpha Therapy (TAT) has been performed, identifying the common issues. Approach. The systematic review was performed in accordance with the PRISMA guidelines, and the literature was searched using the Scopus and PubMed databases. Main results. From the systematic review, three key points should be considered when performing dosimetry in TAT. (1) Biodistribution/Biokinetics: the accuracy of the biodistribution data is a limit to accurate dosimetry in TAT. The biodistribution of alpha-emitting radionuclides throughout the body is difficult to image directly, with surrogate radionuclide imaging, blood/faecal sampling, and animal studies able to provide information. (2) Daughter radionuclides: the decay energy of the alpha-emissions is sufficient to break the bond to the targeting vector, resulting in a release of free daughter radionuclides in the body. Accounting for daughter radionuclide migration is essential. (3) Small-scale dosimetry and microdosimetry: due to the short path length and heterogeneous distribution of alpha-emitters at the target site, small-scale/microdosimetry are important to account for the non-uniform dose distribution in a target region, organ or cell and for assessing the biological effect of alpha-particle radiation. Significance. TAT is a form of cancer treatment capable of delivering a highly localised dose to the tumour environment while sparing the surrounding healthy tissue. Dosimetry is an important part of treatment planning and follow up. Being able to accurately predict the radiation dose to the target region and healthy organs could guide the optimal prescribed activity. Detailed dosimetry models accounting for the three points mentioned above will help give confidence in and guide the clinical application of alpha-emitting radionuclides in targeted cancer therapy.
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Liatsou I, Yu J, Bastiaannet R, Li Z, Hobbs RF, Torgue J, Sgouros G. 212Pb-conjugated anti-rat HER2/ neu antibody against a neu-N derived murine mammary carcinoma cell line: cell kill and RBE in vitro. Int J Radiat Biol 2022; 98:1452-1461. [PMID: 35073214 PMCID: PMC9673603 DOI: 10.1080/09553002.2022.2033341] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE In the current work, the RBE of a 212Pb-conjugated anti-HER2/neu antibody construct has been evaluated, in vitro, by colony formation assay. The RBE was estimated by comparing two absorbed dose-survival curves: the first obtained from the conjugated 212Pb experiments (test radiation), the second obtained by parallel experiments of single bolus irradiation of external beam (reference radiation). MATERIALS AND METHODS Mammary carcinoma NT2.5 cells were treated with (0-3.70) kBq/ml of radiolabeled antibody. Nonspecific binding was assessed with addition of excess amount of unlabeled antibody. The colony formation curves were converted from activity concentration to cell nucleus absorbed dose by simulating the decay and transport of all daughter and secondary particles of 212Pb, using the Monte Carlo code GEANT 4. RESULTS The radiolabeled antibody yielded an RBE of 8.3 at 37% survival and a survival independent RBE (i.e. RBE2) of 9.9. Unbound/untargeted 212Pb-labeled antibody, as obtained in blocking experiments yielded minimal alpha-particle radiation to cells. Conclusions: These results further highlight the importance of specific targeting toward achieving tumor cell kill and low toxicity to normal tissue.
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Affiliation(s)
- Ioanna Liatsou
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
| | - Jing Yu
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
| | - Remco Bastiaannet
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
| | - Zhi Li
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
| | - Robert F. Hobbs
- Department of Radiation Oncology, School of Medicine, Johns Hopkins University, Baltimore, USA
| | | | - George Sgouros
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
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Radiobiology of Targeted Alpha Therapy. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00093-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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8
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Frankhouser DE, Dietze E, Mahabal A, Seewaldt VL. Vascularity and Dynamic Contrast-Enhanced Breast Magnetic Resonance Imaging. FRONTIERS IN RADIOLOGY 2021; 1:735567. [PMID: 37492179 PMCID: PMC10364989 DOI: 10.3389/fradi.2021.735567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 11/11/2021] [Indexed: 07/27/2023]
Abstract
Angiogenesis is a key step in the initiation and progression of an invasive breast cancer. High microvessel density by morphological characterization predicts metastasis and poor survival in women with invasive breast cancers. However, morphologic characterization is subject to variability and only can evaluate a limited portion of an invasive breast cancer. Consequently, breast Magnetic Resonance Imaging (MRI) is currently being evaluated to assess vascularity. Recently, through the new field of radiomics, dynamic contrast enhanced (DCE)-MRI is being used to evaluate vascular density, vascular morphology, and detection of aggressive breast cancer biology. While DCE-MRI is a highly sensitive tool, there are specific features that limit computational evaluation of blood vessels. These include (1) DCE-MRI evaluates gadolinium contrast and does not directly evaluate biology, (2) the resolution of DCE-MRI is insufficient for imaging small blood vessels, and (3) DCE-MRI images are very difficult to co-register. Here we review computational approaches for detection and analysis of blood vessels in DCE-MRI images and present some of the strategies we have developed for co-registry of DCE-MRI images and early detection of vascularization.
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Affiliation(s)
- David E. Frankhouser
- Department of Population Sciences, City of Hope National Medical Center, Duarte, CA, United States
| | - Eric Dietze
- Department of Population Sciences, City of Hope National Medical Center, Duarte, CA, United States
| | - Ashish Mahabal
- Department of Astronomy, Division of Physics, Mathematics, and Astronomy, California Institute of Technology (Caltech), Pasadena, CA, United States
| | - Victoria L. Seewaldt
- Department of Population Sciences, City of Hope National Medical Center, Duarte, CA, United States
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Mu W, Jiang L, Zhang J, Shi Y, Gray JE, Tunali I, Gao C, Sun Y, Tian J, Zhao X, Sun X, Gillies RJ, Schabath MB. Non-invasive decision support for NSCLC treatment using PET/CT radiomics. Nat Commun 2020; 11:5228. [PMID: 33067442 PMCID: PMC7567795 DOI: 10.1038/s41467-020-19116-x] [Citation(s) in RCA: 132] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 09/14/2020] [Indexed: 12/26/2022] Open
Abstract
Two major treatment strategies employed in non-small cell lung cancer, NSCLC, are tyrosine kinase inhibitors, TKIs, and immune checkpoint inhibitors, ICIs. The choice of strategy is based on heterogeneous biomarkers that can dynamically change during therapy. Thus, there is a compelling need to identify comprehensive biomarkers that can be used longitudinally to help guide therapy choice. Herein, we report a 18F-FDG-PET/CT-based deep learning model, which demonstrates high accuracy in EGFR mutation status prediction across patient cohorts from different institutions. A deep learning score (EGFR-DLS) was significantly and positively associated with longer progression free survival (PFS) in patients treated with EGFR-TKIs, while EGFR-DLS is significantly and negatively associated with higher durable clinical benefit, reduced hyperprogression, and longer PFS among patients treated with ICIs. Thus, the EGFR-DLS provides a non-invasive method for precise quantification of EGFR mutation status in NSCLC patients, which is promising to identify NSCLC patients sensitive to EGFR-TKI or ICI-treatments.
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Affiliation(s)
- Wei Mu
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Lei Jiang
- Department of Nuclear Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - JianYuan Zhang
- Department of Nuclear Medicine, the Fourth Hospital of Hebei Medical University, Hebei, China
- Department of Nuclear Medicine, Baoding No.1 Central Hospital, Baoding, Hebei, China
| | - Yu Shi
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Jhanelle E Gray
- Department of Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Ilke Tunali
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Chao Gao
- NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics, Molecular Imaging Research Center (MIRC), Harbin Medical University, Harbin, Heilongjiang, China
- TOF-PET/CT/MR center, the Fourth Hospital of Harbin Medical University, Harbin Medical University, Harbin, Heilongjiang, China
| | - Yingying Sun
- NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics, Molecular Imaging Research Center (MIRC), Harbin Medical University, Harbin, Heilongjiang, China
- TOF-PET/CT/MR center, the Fourth Hospital of Harbin Medical University, Harbin Medical University, Harbin, Heilongjiang, China
| | - Jie Tian
- Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, School of Medicine, Beihang University, Beijing, China
- CAS Key Laboratory of Molecular Imaging, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Xinming Zhao
- Department of Nuclear Medicine, the Fourth Hospital of Hebei Medical University, Hebei, China.
| | - Xilin Sun
- NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics, Molecular Imaging Research Center (MIRC), Harbin Medical University, Harbin, Heilongjiang, China.
- TOF-PET/CT/MR center, the Fourth Hospital of Harbin Medical University, Harbin Medical University, Harbin, Heilongjiang, China.
| | - Robert J Gillies
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
| | - Matthew B Schabath
- Department of Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
- Department of Cancer Epidemiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
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Abstract
Radiopharmaceutical therapy (RPT) is emerging as a safe and effective targeted approach to treating many types of cancer. In RPT, radiation is systemically or locally delivered using pharmaceuticals that either bind preferentially to cancer cells or accumulate by physiological mechanisms. Almost all radionuclides used in RPT emit photons that can be imaged, enabling non-invasive visualization of the biodistribution of the therapeutic agent. Compared with almost all other systemic cancer treatment options, RPT has shown efficacy with minimal toxicity. With the recent FDA approval of several RPT agents, the remarkable potential of this treatment is now being recognized. This Review covers the fundamental properties, clinical development and associated challenges of RPT. Radiopharmaceutical therapy is emerging as a safe and effective approach for the treatment of cancer, offering several advantages over existing therapeutic strategies. Here, Sgouros and colleagues provide an overview of the fundamental properties of radiopharmaceutical therapy, discuss agents in use and in clinical development and highlight the associated translational challenges.
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