Molecular Imaging最新文献

{"title":"Optical and MRI Multimodal Tracing of Stem Cells In Vivo","authors":"Jia Yang, Min Yan, Zhong Wang, Cong Zhang, Miao Guan, Zhenglong Sun","doi":"10.1155/2023/4223485","DOIUrl":"https://doi.org/10.1155/2023/4223485","url":null,"abstract":"Stem cell therapy has shown great clinical potential in oncology, injury, inflammation, and cardiovascular disease. However, due to the technical limitations of the in vivo visualization of transplanted stem cells, the therapeutic mechanisms and biosafety of stem cells in vivo are poorly defined, which limits the speed of clinical translation. The commonly used methods for the in vivo tracing of stem cells currently include optical imaging, magnetic resonance imaging (MRI), and nuclear medicine imaging. However, nuclear medicine imaging involves radioactive materials, MRI has low resolution at the cellular level, and optical imaging has poor tissue penetration in vivo. It is difficult for a single imaging method to simultaneously achieve the high penetration, high resolution, and noninvasiveness needed for in vivo imaging. However, multimodal imaging combines the advantages of different imaging modalities to determine the fate of stem cells in vivo in a multidimensional way. This review provides an overview of various multimodal imaging technologies and labeling methods commonly used for tracing stem cells, including optical imaging, MRI, and the combination of the two, while explaining the principles involved, comparing the advantages and disadvantages of different combination schemes, and discussing the challenges and prospects of human stem cell tracking techniques.","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":"76 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138744282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Targeted Imaging of Endometriosis and Image-Guided Resection of Lesions Using Gonadotropin-Releasing Hormone Analogue-Modified Indocyanine Green","authors":"Jing Peng, Qiyu Liu, Tao Pu, Mingxing Zhang, Meng Zhang, Ming Du, Guiling Li, Xiaoyan Zhang, Congjian Xu","doi":"10.1155/2023/6674054","DOIUrl":"https://doi.org/10.1155/2023/6674054","url":null,"abstract":"<i>Objective</i>. In this study, we utilized gonadotropin-releasing hormone analogue-modified indocyanine green (GnRHa-ICG) to improve the accuracy of intraoperative recognition and resection of endometriotic lesions. <i>Methods</i>. Gonadotropin-releasing hormone receptor (GnRHR) expression was detected in endometriosis tissues and cell lines via immunohistochemistry and western blotting. The in vitro binding capacities of GnRHa, GnRHa-ICG, and ICG were determined using fluorescence microscopy and flow cytometry. In vivo imaging was performed in mouse models of endometriosis using a near-infrared fluorescence (NIRF) imaging system and fluorescence navigation system. The ex vivo binding capacity was determined using confocal fluorescence microscopy. <i>Results</i>. GnRHa-ICG exhibited a significantly stronger binding capacity to endometriotic cells and tissues than ICG. In mice with endometriosis, GnRHa-ICG specifically imaged endometriotic tissues (EMTs) after intraperitoneal administration, whereas ICG exhibited signals in the intestine. GnRHa-ICG showed the highest fluorescence signals in the EMTs at 2 h and a good signal-to-noise ratio at 48 h postadministration. Compared with traditional surgery under white light, targeted NIRF imaging-guided surgery completely resected endometriotic lesions with a sensitivity of 97.3% and specificity of 77.8%. No obvious toxicity was observed in routine blood tests, serum biochemicals, or histopathology in mice. <i>Conclusions</i>. GnRHa-ICG specifically recognized and localized endometriotic lesions and guided complete resection of lesions with high accuracy.","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":"507 ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2023-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138506377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First-in-Human PET Imaging of [¹⁸F]SDM-4MP3: A Cautionary Tale.","authors":"Kimberly L Desmond,&nbsp;Anton Lindberg,&nbsp;Armando Garcia,&nbsp;Junchao Tong,&nbsp;Michael B Harkness,&nbsp;Elena Dobrota,&nbsp;Kelly Smart,&nbsp;Carme Uribe,&nbsp;Jeffrey H Meyer,&nbsp;Sylvain Houle,&nbsp;Antonio P Strafella,&nbsp;Songye Li,&nbsp;Yiyun Huang,&nbsp;Neil Vasdev","doi":"10.1155/2023/8826977","DOIUrl":"10.1155/2023/8826977","url":null,"abstract":"<p><p>[¹⁸F]SynVesT-1 is a PET radiopharmaceutical that binds to the synaptic vesicle protein 2A (SV2A) and serves as a biomarker of synaptic density with widespread clinical research applications in psychiatry and neurodegeneration. The initial goal of this study was to concurrently conduct PET imaging studies with [¹⁸F]SynVesT-1 at our laboratories. However, the data in the first two human PET studies had anomalous biodistribution despite the injected product meeting all specifications during the prerelease quality control protocols. Further investigation, including imaging in rats as well as proton and carbon 2D-NMR spectroscopic studies, led to the discovery that a derivative of the precursor had been received from the manufacturer. Hence, we report our investigation and the first-in-human study of [¹⁸F]SDM-4MP3, a structural variant of [¹⁸F]SynVesT-1, which does not have the requisite characteristics as a PET radiopharmaceutical for imaging SV2A in the central nervous system.</p>","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":"2023 ","pages":"8826977"},"PeriodicalIF":2.8,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10504053/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10306687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PET and SPECT Imaging of ALS: An Educational Review.","authors":"Ayaan M Jamali,&nbsp;Manasa Kethamreddy,&nbsp;Brian J Burkett,&nbsp;John D Port,&nbsp;Mukesh K Pandey","doi":"10.1155/2023/5864391","DOIUrl":"10.1155/2023/5864391","url":null,"abstract":"<p><p>Amyotrophic lateral sclerosis (ALS) is a disease leading to progressive motor degeneration and ultimately death. It is a complex disease that can take a significantly long time to be diagnosed, as other similar pathological conditions must be ruled out for a definite diagnosis of ALS. Noninvasive imaging of ALS has shed light on disease pathology and altered biochemistry in the ALS brain. Other than magnetic resonance imaging (MRI), two types of functional imaging, positron emission tomography (PET) and single photon emission computed tomography (SPECT), have provided valuable data about what happens in the brain of ALS patients compared to healthy controls. PET imaging has revealed a specific pattern of brain metabolism through [¹⁸F]FDG, while other radiotracers have uncovered neuroinflammation, changes in neuronal density, and protein aggregation. SPECT imaging has shown a general decrease in regional cerebral blood flow (rCBF) in ALS patients. This educational review summarizes the current state of ALS imaging with various PET and SPECT radiopharmaceuticals to better understand the pathophysiology of ALS.</p>","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":"2023 ","pages":"5864391"},"PeriodicalIF":2.8,"publicationDate":"2023-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10460279/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10464600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preliminary Assessment of Reference Region Quantification and Reduced Scanning Times for [¹⁸F]SynVesT-1 PET in Parkinson's Disease.","authors":"Kelly Smart, Carme Uribe, Kimberly L Desmond, Sarah L Martin, Neil Vasdev, Antonio P Strafella","doi":"10.1155/2023/1855985","DOIUrl":"10.1155/2023/1855985","url":null,"abstract":"<p><p>Synaptic density in the central nervous system can be measured <i>in vivo</i> using PET with [¹⁸F]SynVesT-1. While [¹⁸F]SynVesT-1 has been proven to be a powerful radiopharmaceutical for PET imaging of neurodegenerative disorders such as Parkinson's disease (PD), its currently validated acquisition and quantification protocols are invasive and technically challenging in these populations due to the arterial sampling and relatively long scanning times. The objectives of this work were to evaluate a noninvasive (reference tissue) quantification method for [¹⁸F]SynVesT-1 in PD patients and to determine the minimum scan time necessary for accurate quantification. [¹⁸F]SynVesT-1 PET scans were acquired in 5 patients with PD and 3 healthy control subjects for 120 min with arterial blood sampling. Quantification was performed using the one-tissue compartment model (1TCM) with arterial input function, as well as with the simplified reference tissue model (SRTM) to estimate binding potential (BP_ND) using centrum semiovale (CS) as a reference region. The SRTM2 method was used with <i>k</i>₂' fixed to either a sample average value (0.037 min^-1) or a value estimated first through coupled fitting across regions for each participant. Direct SRTM estimation and the Logan reference region graphical method were also evaluated. There were no significant group differences in CS volume, radiotracer uptake, or efflux (<i>ps</i> > 0.47). Each fitting method produced BP_ND estimates in close agreement with those derived from the 1TCM (subject <i>R</i>²s > 0.98, bias < 10%), with no difference in bias between the control and PD groups. With SRTM2, BP_ND estimates from truncated scan data as short as 80 min produced values in excellent agreement with the data from the full 120 min scans (bias < 6%). While these are preliminary results from a small sample of patients with PD (<i>n</i> = 5), this work suggests that accurate synaptic density quantification may be performed without blood sampling and with scan time under 90 minutes. If further validated, these simplified procedures for [¹⁸F]SynVesT-1 PET quantification can facilitate its application as a clinical research imaging technology and allow for larger study samples and include a broader scope of patients including those with neurodegenerative diseases.</p>","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":"2023 ","pages":"1855985"},"PeriodicalIF":2.2,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10445483/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10071155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Intraperitoneal [¹⁸F]-FDOPA Administration for Micro-PET Imaging in Mice and Assessment of the Effect of Subchronic Ketamine Dosing on Dopamine Synthesis Capacity.","authors":"Els F Halff, Sridhar Natesan, David R Bonsall, Mattia Veronese, Anna Garcia-Hidalgo, Michelle Kokkinou, Sac-Pham Tang, Laura J Riggall, Roger N Gunn, Elaine E Irvine, Dominic J Withers, Lisa A Wells, Oliver D Howes","doi":"10.1155/2022/4419221","DOIUrl":"10.1155/2022/4419221","url":null,"abstract":"<p><p>Positron emission tomography (PET) using the radiotracer [¹⁸F]-FDOPA provides a tool for studying brain dopamine synthesis capacity in animals and humans. We have previously standardised a micro-PET methodology in mice by intravenously administering [¹⁸F]-FDOPA via jugular vein cannulation and assessment of striatal dopamine synthesis capacity, indexed as the influx rate constant <i>K</i> _<i>i</i> ^Mod of [¹⁸F]-FDOPA, using an extended graphical Patlak analysis with the cerebellum as a reference region. This enables a direct comparison between preclinical and clinical output values. However, chronic intravenous catheters are technically difficult to maintain for longitudinal studies. Hence, in this study, intraperitoneal administration of [¹⁸F]-FDOPA was evaluated as a less-invasive alternative that facilitates longitudinal imaging. Our experiments comprised the following assessments: (i) comparison of [¹⁸F]-FDOPA uptake between intravenous and intraperitoneal radiotracer administration and optimisation of the time window used for extended Patlak analysis, (ii) comparison of <i>Ki</i> ^Mod in a within-subject design of both administration routes, (iii) test-retest evaluation of <i>Ki</i> ^Mod in a within-subject design of intraperitoneal radiotracer administration, and (iv) validation of <i>Ki</i> ^Mod estimates by comparing the two administration routes in a mouse model of hyperdopaminergia induced by subchronic ketamine. Our results demonstrate that intraperitoneal [¹⁸F]-FDOPA administration resulted in good brain uptake, with no significant effect of administration route on <i>Ki</i> ^Mod estimates (intraperitoneal: 0.024 ± 0.0047 min^-1, intravenous: 0.022 ± 0.0041 min^-1, <i>p</i> = 0.42) and similar coefficient of variation (intraperitoneal: 19.6%; intravenous: 18.4%). The technique had a moderate test-retest validity (intraclass correlation coefficient (ICC) = 0.52, <i>N</i> = 6) and thus supports longitudinal studies. Following subchronic ketamine administration, elevated <i>K</i> _<i>i</i> ^Mod as compared to control condition was measured with a large effect size for both methods (intraperitoneal: Cohen's <i>d</i> = 1.3; intravenous: Cohen's <i>d</i> = 0.9), providing further evidence that ketamine has lasting effects on the dopamine system, which could contribute to its therapeutic actions and/or abuse liability.</p>","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":"2022 ","pages":"4419221"},"PeriodicalIF":2.2,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9881672/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9165489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[¹⁸F]-(2S,4R)4-Fluoroglutamine PET Imaging of Glutamine Metabolism in Murine Models of Hepatocellular Carcinoma (HCC).","authors":"Youngho Seo,&nbsp;Miranda C Craig,&nbsp;Stephanie T Murphy,&nbsp;Jinjin Feng,&nbsp;Xin Chen,&nbsp;Mariia Yuneva","doi":"10.1155/2022/5185951","DOIUrl":"https://doi.org/10.1155/2022/5185951","url":null,"abstract":"<p><strong>Purpose: </strong>Quantitative <i>in vivo</i> [¹⁸F]-(2S,4R)4-fluoroglutamine ([¹⁸F]4-FGln or more simply [¹⁸F]FGln) metabolic kinetic parameters are compared with activity levels of glutamine metabolism in different types of hepatocellular carcinoma (HCC).</p><p><strong>Methods: </strong>For this study, we used two transgenic mouse models of HCC induced by protooncogenes, MYC, and MET. Biochemical data have shown that tumors induced by MYC have increased levels of glutamine metabolism compared to those induced by MET. One-hour dynamic [¹⁸F]FGln PET data were acquired and reconstructed for fasted MYC mice (<i>n</i> = 11 tumors from 7 animals), fasted MET mice (<i>n</i> = 8 tumors from 6 animals), fasted FVBN controls (<i>n</i> = 8 normal liver regions from 6 animals), nonfasted MYC mice (<i>n</i> = 16 tumors from 6 animals), and nonfasted FVBN controls (<i>n</i> = 8 normal liver regions from 3 animals). The influx rate constants (<i>K</i> ₁) using the one-tissue compartment model were derived for each tumor with the left ventricular blood pool input function.</p><p><strong>Results: </strong>Influx rate constants were significantly higher for MYC tumors (<i>K</i> ₁ = 0.374 ± 0.133) than for MET tumors (<i>K</i> ₁ = 0.141 ± 0.058) under fasting conditions (<i>P</i> = 0.0002). Rate constants were also significantly lower for MET tumors (<i>K</i> ₁ = 0.141 ± 0.135) than normal livers (<i>K</i> ₁ = 0.332 ± 0.179) under fasting conditions (<i>P</i> = 0.0123). Fasting conditions tested for MYC tumors and normal livers did not result in any significant difference with <i>P</i> values > 0.005.</p><p><strong>Conclusion: </strong>Higher influx rate constants corresponded to elevated levels of glutamine metabolism as determined by biochemical assays. The data showed that there is a distinctive difference in glutamine metabolism between MYC and MET tumors. Our study has demonstrated the potential of [¹⁸F]FGln PET imaging as a tool to assess glutamine metabolism in HCC tumors <i>in vivo</i> with a caution that it may not be able to clearly distinguish HCC tumors from normal liver tissue.</p>","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":" ","pages":"5185951"},"PeriodicalIF":2.8,"publicationDate":"2022-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9351703/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40615091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance Evaluation of a Preclinical SPECT Scanner with a Collimator Designed for Medium-Sized Animals.","authors":"Yohji Matsusaka,&nbsp;Rudolf A Werner,&nbsp;Paula Arias-Loza,&nbsp;Naoko Nose,&nbsp;Takanori Sasaki,&nbsp;Xinyu Chen,&nbsp;Constantin Lapa,&nbsp;Takahiro Higuchi","doi":"10.1155/2022/9810097","DOIUrl":"https://doi.org/10.1155/2022/9810097","url":null,"abstract":"<p><strong>Background: </strong>Equipped with two stationary detectors, a large bore collimator for medium-sized animals has been recently introduced for dedicated preclinical single-photon emission computed tomography (SPECT) imaging. We aimed to evaluate the basic performance of the system using phantoms and healthy rabbits.</p><p><strong>Methods: </strong>A general-purpose medium-sized animal (GP-MSA) collimator with 135 mm bore diameter and thirty-three holes of 2.5 mm diameter was installed on an ultrahigh-resolution scanner equipped with two large stationary detectors (U-SPECT5-E/CT). The sensitivity and uniformity were investigated using a point source and a cylinder phantom containing ^99mTc-pertechnetate, respectively. Uniformity (in %) was derived using volumes of interest (VOIs) on images of the cylinder phantom and calculated as [(maximum count - minimum count)/(maximum count + minimum count) × 100], with lower values of % indicating superior performance. The spatial resolution and contrast-to-noise ratios (CNRs) were evaluated with images of a hot-rod Derenzo phantom using different activity concentrations. Feasibility of <i>in vivo</i> SPECT imaging was finally confirmed by rabbit imaging with the most commonly used clinical myocardial perfusion SPECT agent [^99mTc]Tc-sestamibi (dynamic acquisition with a scan time of 5 min).</p><p><strong>Results: </strong>In the performance evaluation, a sensitivity of 790 cps/MBq, a spatial resolution with the hot-rod phantom of 2.5 mm, and a uniformity of 39.2% were achieved. The CNRs of the rod size 2.5 mm were 1.37, 1.24, 1.20, and 0.85 for activity concentration of 29.2, 1.0, 0.5, and 0.1 MBq/mL, respectively. Dynamic SPECT imaging in rabbits allowed to visualize most of the thorax and to generate time-activity curves of the left myocardial wall and ventricular cavity.</p><p><strong>Conclusion: </strong>Preclinical U-SPECT5-E/CT equipped with a large bore collimator demonstrated adequate sensitivity and resolution for <i>in vivo</i> rabbit imaging. Along with its unique features of SPECT molecular functional imaging is a superior collimator technology that is applicable to medium-sized animal models and thus may promote translational research for diagnostic purposes and development of novel therapeutics.</p>","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":" ","pages":"9810097"},"PeriodicalIF":2.8,"publicationDate":"2022-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9328189/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40571732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In Vivo Distribution and Therapeutic Efficacy of Radioiodine-Labeled pH-Low Insertion Peptide Variant 3 in a Mouse Model of Breast Cancer.","authors":"Min Zhang,&nbsp;Yue Xi,&nbsp;Hong Chen,&nbsp;Wangxi Hai,&nbsp;Biao Li","doi":"10.1155/2022/7456365","DOIUrl":"https://doi.org/10.1155/2022/7456365","url":null,"abstract":"<p><strong>Purpose: </strong>Extracellular acidity is a marker of highly aggressive breast cancer (BC). pH-low insertion peptides (pHLIPs) target the acidic tumor microenvironment. This study evaluates the distribution and therapeutic efficacy of radioiodine-labeled pHLIP variant 3 (Var3) in a mouse model of BC.</p><p><strong>Methods: </strong>The binding of fluorescein isothiocyanate (FITC)- or radioiodine-125 (¹²⁵I) labeled Var3-pHLIP to MDA-MB-231, 4T1, and SK-BR-3 BC cell lines under different pH values was evaluated in vitro. The distribution of ¹²⁵I-labeled Var3-pHLIP and wild-type- (WT-) pHLIP in tumor-bearing mice was analyzed in vivo using micro-SPECT/CT imaging. The therapeutic efficacy of radioiodine-131 (¹³¹I)-labeled Var3-pHLIP in MDA-MB-231 xenografts was evaluated by relative tumor volume measurement and immunohistochemical analysis.</p><p><strong>Results: </strong>The binding ability of FITC- or ¹²⁵I-labeled Var3-pHLIP to tumor cells increased with the decrease in pH. The tumor-to-background ratio of ¹²⁵I-Var3-pHLIP in BC xenografts showed the best imaging contrast at 24 h or 48 h postinjection. The uptake of ¹²⁵I-Var3-pHLIP in MDA-MB-231 xenografts at 2 h postinjection was significantly higher than that of ¹²⁵I-WT-pHLIP (3.76 ± 0.37 vs. 2.87 ± 0.60%ID/g, <i>p</i> = 0.046). The relative tumor volume in MDA-MB-231 xenografts was significantly lower in the ¹³¹I-Var3-pHLIP-treated group than in the groups treated with Var3-pHLIP (<i>p</i> = 0.027), ¹³¹I (<i>p</i> = 0.001), and saline (<i>p</i> < 0.001). The ¹³¹I-Var 3-pHLIP group presented a lower expression of Ki67 and a higher expression of caspase 3.</p><p><strong>Conclusion: </strong>Radioiodine-labeled Var3-pHLIP effectively targeted BC cells in an acidic environment and inhibited the growth of MDA-MB-231 xenografts by ionizing radiation.</p>","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":" ","pages":"7456365"},"PeriodicalIF":2.8,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9281440/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40571731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Dynamic ¹⁸F-FDG PET/CT for Distinguishing Intrapulmonary Metastases from Synchronous Multiple Primary Lung Cancer.","authors":"Weize Lv,&nbsp;Min Yang,&nbsp;Hongcheng Zhong,&nbsp;Xiaojin Wang,&nbsp;Shuai Yang,&nbsp;Lei Bi,&nbsp;Jianzhong Xian,&nbsp;Xiaofeng Pei,&nbsp;Xinghua He,&nbsp;Ying Wang,&nbsp;Zhong Lin,&nbsp;Qingdong Cao,&nbsp;Hongjun Jin,&nbsp;Hong Shan","doi":"10.1155/2022/8081299","DOIUrl":"https://doi.org/10.1155/2022/8081299","url":null,"abstract":"<p><p>It has been a big challenge to distinguish synchronous multiple primary lung cancer (sMPLC) from primary lung cancer with intrapulmonary metastases (IPM). We aimed to assess the clinical application of dynamic ¹⁸F-FDG PET/CT in patients with multiple lung cancer nodules. We enrolled patients with multiple pulmonary nodules who had undergone dynamic ¹⁸F-FDG PET/CT and divided them into sMPLC and IPM groups based on comprehensive features. The SUV_max, fitted <i>K</i> _<i>i</i> value based on dynamic scanning, and corresponding maximum diameter (<i>D</i> _max) from the two largest tumors were determined in each patient. We determined the absolute between-tumor difference of SUV_max/<i>D</i> _max and <i>K</i> _<i>i</i> /<i>D</i> _max (ΔSUV_max/<i>D</i> _max; Δ<i>K</i> _<i>i</i> /<i>D</i> _max) and assessed the between-group differences. Further, the diagnostic accuracy was evaluated by ROC analysis and the correlation between ΔSUV_max/<i>D</i> _max and Δ<i>K</i> _<i>i</i> /D_max from all groups was determined. There was no significant difference for ΔSUV_max/<i>D</i> _max between the IPM and sMPLC groups, while the IPM group had a significantly higher Δ<i>K</i> _<i>i</i> /D_max than the sMPLC group. The AUC of Δ<i>K</i> _<i>i</i> /<i>D</i> _max for differentiating sMPLC from IPM was 0.80 (cut-off value of <i>K</i> _<i>i</i> = 0.0059, sensitivity 79%, specificity 75%, <i>p</i> < 0.001). There was a good correlation (Pearson <i>r</i> = 0.91, 95% CI: 0.79-0.96, <i>p</i> < 0.0001) between ΔSUV_max/<i>D</i> _max and Δ<i>K</i> _<i>i</i> /<i>D</i> _max in the IPM group but not in the sMPLC group (Pearson <i>r</i> = 0.45, <i>p</i> > 0.05). Dynamic ¹⁸F-FDG PET/CT could be a useful tool for distinguishing sMPLC from IPM. <i>K</i> _<i>i</i> calculation based on Patlak graphic analysis could be more sensitive than SUV_max in discriminating IPM from sMPLC in patients with multiple lung cancer nodules.</p>","PeriodicalId":18855,"journal":{"name":"Molecular Imaging","volume":" ","pages":"8081299"},"PeriodicalIF":2.8,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9281433/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40556104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}