Molecular Imaging and Biology最新文献

{"title":"Comparison of [¹⁸F]DPA-814 with [¹⁸F]DPA-714 for TSPO Imaging in an Experimental Model.","authors":"J van der Bie, J Bakker, E J Verschoor, E Nutma, J Middeldorp, W Beaino, M Kassiou, J J Danon, J A M Langermans, A D Windhorst, M A Stammes","doi":"10.1007/s11307-026-02094-9","DOIUrl":"https://doi.org/10.1007/s11307-026-02094-9","url":null,"abstract":"<p><strong>Purpose: </strong>[¹⁸F]DPA-714 is a valuable tracer for studying (neuro)inflammation, with well-characterized tracer kinetics and an established imaging window. However, its clinical utility is restricted by the TSPO polymorphism (rs6971), which influences binding affinity in humans. The newly developed tracer [¹⁸F]DPA-814 overcomes this limitation and has shown promising results in a preclinical rat model. To further assess its clinical potential, we compared [¹⁸F]DPA-814 to [¹⁸F]DPA-714 for inflammation imaging in SARS-CoV-2-infected macaques in a longitudinal setting.</p><p><strong>Procedures: </strong>Dynamic positron emission tomography (PET) imaging was conducted in four healthy macaques to identify the optimal imaging window for [¹⁸F]DPA-814. Four additional macaques were infected with SARS-CoV-2 and monitored for 12 months using whole-body PET-computed tomography (CT) with both tracers. Baseline scans were compared to PET-CTs obtained at 4, 9 and 16 days and at 6 and 12 months post-infection, covering the head, thorax and abdomen. Tracer uptake was assessed in several organs.</p><p><strong>Results: </strong>At baseline, [¹⁸F]DPA-814 showed higher lung uptake with minimal washout compared to [¹⁸F]DPA-714. Although lung lesions developed after infection, [¹⁸F]DPA-814 did not demonstrate lesion-specific uptake, unlike [¹⁸F]DPA-714. In the brain, the tracers also displayed divergent uptake patterns despite comparable TSPO levels across animals and regions.</p><p><strong>Conclusions: </strong>[¹⁸F]DPA-814 exhibits a distinct whole-body distribution, particularly in the lungs and brain, in both naïve and SARS-CoV-2-infected macaques compared with [¹⁸F]DPA-714, likely reflecting differences in tracer kinetics. Based on these data, [¹⁸F]DPA-814 may not fully replace [¹⁸F]DPA-714 for lung and brain imaging, and further studies are required to evaluate its suitability in other anatomical regions.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147593200","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":"Preclinical Study of Radiolabeled LyP-1 for Detecting Sunitinib-induced Changes in the Tumor Microenvironment and Synergistic Antitumor Effects in Triple-negative Breast Cancer.","authors":"Sisi Liao, Qinli Qi, Lifang Jin, Jiali Gong, Lingzhou Zhao, Jinhua Zhao, Meilin Zhu, Ningning Song","doi":"10.1007/s11307-026-02083-y","DOIUrl":"https://doi.org/10.1007/s11307-026-02083-y","url":null,"abstract":"<p><strong>Purpose: </strong>Sunitinib is an anti-angiogenic drug that can induce drug resistance characterized by hypoxia. We aimed to synthesize two novel radiolabeled LyP-1 peptides, ^99mTc-HYNIC-LyP-1 and ¹³¹I-LyP-1, to detect sunitinib-induced changes in the tumor microenvironment and improve the therapeutic effects in triple-negative breast cancer (TNBC) mice models.</p><p><strong>Methods: </strong>We synthesized ^99mTc-HYNIC-LyP-1 using hydrazinonicotinamide (HYNIC) as the chelating agent and labeled the LyP-1 peptide with ¹³¹I using the chloramine-T method to synthesize ¹³¹I-LyP-1. Radiochemical purity and stability of the peptides were assessed in vitro using thin-layer chromatography. Tumor accumulation and biodistribution of ^99mTc-HYNIC-LyP-1 were measured in 4T1 xenografts with or without sunitinib treatment. Immunohistochemical analysis was performed to detect sunitinib-induced changes. The therapeutic potential of ¹³¹I-LyP-1 alone and in combination with sunitinib was evaluated in a TNBC mouse model.</p><p><strong>Results: </strong>^99mTc-HYNIC-LyP-1 and ¹³¹I-LyP-1 could be readily prepared with satisfactory labeling efficiency (95.4% ± 0.6% and 72.5% ± 4.5%, respectively) and stability (both more than 90%) in vitro. Micro-single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging of mice transplanted with 4T1 tumors using ^99mTc-HYNIC-LyP-1 demonstrated that the uptake of this probe was high in 4T1 xenografts treated with sunitinib at 90 min, whereas it was mild in the control group. Semiquantitative analysis of the ratio of radioactivity intensity at tumor site to that of adjacent muscles (T/M value) showed that the average T/M value of the sunitinib treatment group at 90 min was 3.27, while it was 0.91 in the control group (p = 0.0022). ¹³¹I-LyP-1 could significantly inhibited tumor growth with good organ compatibility and had a synergistic therapeutic effect when combined with sunitinib, with an approximately threefold reduction in the tumor volume in comparison with the control group CONCLUSION: Micro-SPECT/CT imaging using ^99mTc-HYNIC-LyP-1 can be used to monitor sunitinib-induced changes in the TNBC tumor microenvironment. The combination of ¹³¹I-LyP-1 and sunitinib may serve as a novel treatment for TNBC.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147593261","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":"Astrocyte Activation Persists after Recovery of Myelin and Motor Deficits in the Cuprizone Model: a Longitudinal PET and CNS Tissue Analysis Study.","authors":"V Pegoretti, A S Boerema, J W A Sijbesma, L E R Dietz, N Alberts, W Douwenga, U L M Eisel, E F J de Vries","doi":"10.1007/s11307-026-02098-5","DOIUrl":"https://doi.org/10.1007/s11307-026-02098-5","url":null,"abstract":"<p><strong>Purpose: </strong>The cuprizone (CPZ) mouse model for multiple sclerosis enables researchers to investigate the underlying mechanisms of demyelination and remyelination, as well as the effect of therapeutic interventions thereon. Over the last five decades, research revealed detailed analyses of brain tissue derived from CPZ-fed animals at different times of de- and re-myelination. Yet, longitudinal analysis of the effects of a CPZ diet on locomotor performance, myelination and neuroinflammation over a two-month recovery period are still unexplored.</p><p><strong>Procedures: </strong>In this study, we comprehensively examined behavioural and neuropathological changes in the CPZ mouse model for a follow-up period of two months. We combined a longitudinal PET imaging approach with a more traditional approach of obtaining tissue and performing immunohistochemistry and behavioural tests in cohorts.</p><p><strong>Results: </strong>We found that mice fed with 0.2% CPZ for 5 weeks showed transient motor deficits which recovered quickly after cuprizone was removed from the diet. Similarly, remyelination also promptly restored myelin content after CPZ toxic insult, as seen by PET imaging with [¹¹C]MeDAS and myelin histological staining. Remarkably, five weeks of CPZ feeding led to persistent glial activation, especially in the corpus callosum, for at least two months. This effect was measured both with [¹¹C]PK11195 PET and with immunohistochemical staining for microglia and astrocytes.</p><p><strong>Conclusions: </strong>Taken together, this longitudinal study reveals that a five-week CPZ diet leads to transient motor and loss of myelin, which recover quickly after CPZ is removed. In contrast, neuroinflammation persists for at least two months following exposure and is mainly driven by astrocyte activation. The study warrants deeper analysis of the sustained neuroinflammatory response in the context of demyelinating diseases.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147513493","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":"Comparison of [¹⁸F]FDG and [¹⁸F]PSMA-1007 PET/CT in the Evaluation of Muscle-Invasive Bladder Cancer: A Pilot Feasibility Study.","authors":"Natália Dalsenter Avilez, Ricardo N Tineo, Juliano Tomé Rodrigues, Arthur Degani Ottaiano, Helena P A Saito, Bárbara Juarez Amorim, José Barreto Campello Carvalheira, Leonardo O Reis, Celso Dario Ramos","doi":"10.1007/s11307-026-02085-w","DOIUrl":"https://doi.org/10.1007/s11307-026-02085-w","url":null,"abstract":"<p><strong>Purpose: </strong>To compare the diagnostic performance of [¹⁸F]FDG and [¹⁸F]PSMA‑1007 PET/CT for detecting primary tumors, regional lymph node involvement, and distant metastases in recently diagnosed muscle‑invasive bladder cancer (MIBC).</p><p><strong>Methods: </strong>Prospective single‑center cohort of six patients (ages 57-82). Both PET/CTs were acquired within 30 days under EANM/SNMMI-conformant protocols, with blinded consensus readings and post-diuretic pelvic acquisitions.</p><p><strong>Results: </strong>[¹⁸F]PSMA‑1007 identified 15 lesions versus 14 with [¹⁸F]FDG. Primary bladder lesions were detected in 5 of 6 patients, compared to 3 of 6 patients. Both tracers detected nodal metastases in three patients and bone metastases in one. An [¹⁸F]FDG‑avid pulmonary lesion near the spleen was not detected with [¹⁸F]PSMA‑1007 owing to physiological splenic uptake.</p><p><strong>Conclusion: </strong>Both tracers showed comparable sensitivity for metastatic disease. The hepatobiliary clearance of [¹⁸F]PSMA‑1007 improved visualization of intravesical disease, supporting its use in staging and potential theranostic strategies in selected MIBC patients. Such real-world findings inform refinements for future study procedures, logistics, and methodological design, which are essential for minimizing research waste by identifying potential problems early.</p><p><strong>Trial registration: </strong>Not applicable.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147504372","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":"The Binding of the High Affinity Radioligand Fallypride to the D2-dopamine Receptor is Sensitive to Injected Mass - a PET Study in Rodents.","authors":"Miklós Tóth, Lenke Tari, Sangram Nag, Tian Qiu, Zhisheng Jia, Jenny Häggkvist, Jogeshwar Mukherjee, Andrea Varrone, Christer Halldin, Lars Farde","doi":"10.1007/s11307-026-02096-7","DOIUrl":"https://doi.org/10.1007/s11307-026-02096-7","url":null,"abstract":"<p><strong>Purpose: </strong>Fallypride is a widely used high affinity radioligand for quantification of D2-dopamine receptor binding in small animal PET imaging. To examine the effect of mass both [¹⁸F]fallypride and [¹¹C]fallypride was injected in mice over a wide range of molar activity and the binding potential (BP) was compared.</p><p><strong>Procedures: </strong>Eight mice (C57BL/6 J) went through three PET measurements within two weeks. [¹¹C]fallypride with the highest possible molar activity (MA) and [¹⁸F]fallypride with normal and lower molar activity (lowerMA).</p><p><strong>Results: </strong>The binding of [¹¹C]fallypride was highest with a BP_ND of 13.5 ± 1.1 BP_ND. The binding of [¹⁸F]fallypride was lower, 8.6 ± 2.2 BP_ND in the normal condition and 5.3 ± 1.3 BP_ND at the lowerMA condition. By consequence, BP_ND showed a strong negative correlation with injected mass (R2 = 0.95, P < 0.05). Binding data were entered in a Scatchard analysis yielding a B_max of 62 pmol/g and a K_D of 0.25 nM.</p><p><strong>Conclusion: </strong>In this PET study in mice the average radioligand occupancy was estimated to 19% even for ¹¹C-labeled fallypride despite the high MA of 153.3 GBq/µmol and low injected mass of 0.03 µg. Therefore, high affinity radioligands should be applied with care in small animal PET studies and radiochemistry has to be at its best to assure that tracer conditions are met in small animal imaging PET imaging.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147468569","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":"Magnetically Controlled Nanocarriers for Site-Specific Drug Delivery and Theranostics in Cancer Precision Medicine.","authors":"Loushambam Samananda Singh, Chabungbam Satyananda Singh, Thounaojam Premlata","doi":"10.1007/s11307-026-02097-6","DOIUrl":"https://doi.org/10.1007/s11307-026-02097-6","url":null,"abstract":"<p><p>The growing demand for precision oncology has intensified interest in magnetically controlled nanocarriers (MCNCs) as versatile platforms for targeted drug delivery and theranostics. Conventional cancer therapies are often limited by nonspecific drug distribution, systemic toxicity, and poor efficacy against heterogeneous tumors. MCNCs, typically based on superparamagnetic iron oxide nanoparticles and hybrid composites, address these limitations by enabling site-specific accumulation, stimuli-responsive release, and real-time imaging in external magnetic fields. These systems integrate diagnostic and therapeutic functions within a single platform, advancing the concept of image-guided and personalized medicine. Recent advances in surface engineering, biodegradable ferrites, and magnetic-plasmonic hybrids have enhanced their biocompatibility, stability, and multimodal performance. Furthermore, their incorporation into combination therapies, such as magnetic hyperthermia, photothermal therapy, and immunotherapy, has demonstrated synergistic antitumor effects. Despite these advances, translational barriers persist, including challenges in deep tissue targeting, biosafety validation, scalable synthesis, and regulatory standardization. Integrating AI-driven modeling and digital twins can optimize the design, dosing, and magnetic field control for personalized therapy. Collectively, magnetically regulated theranostic nanoplatforms represent a promising frontier in precision cancer medicine, bridging diagnosis, therapy, and real-time monitoring toward safer, more effective, and patient-tailored oncologic care.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147468498","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":"Value of Imaging Parameters of [¹⁸F]FDG PET/CT and Serological Indices in Predicting Lymph Node Metastasis in Intrahepatic Cholangiocarcinoma.","authors":"Yihan Yan, Lifang Pang, Yibo He, Zhenghao Jiang, Yiqiu Zhang","doi":"10.1007/s11307-026-02089-6","DOIUrl":"https://doi.org/10.1007/s11307-026-02089-6","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to evaluate the value of [¹⁸F]FDG PET/CT parameters and serological indices in predicting lymph node metastasis (LNM) in patients with intrahepatic cholangiocarcinoma (ICC) preoperatively.</p><p><strong>Methods: </strong>The study included 102 patients with ICC diagnosed between January 2018 and December 2022. All patients underwent preoperative [¹⁸F]FDG PET/CT scanning and serological marker evaluations before surgical tumor resection. The [¹⁸F]FDG PET/CT scanning was jointly evaluated by two nuclear medicine physicians blinded to the clinical information and compared with postoperative pathologic results. The tumor SUVmax, tumor-to-background ratios (TBR), SUVpeak, and total lesion glycolysis (TLG) were obtained from the PET/CT scans. Presurgical serological testing included carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA). The results were analyzed by bivariate and multivariate logistic regression to develop a prediction model for LNM.</p><p><strong>Results: </strong>Among the 102 patients with ICC, 60 (58.8%) patients had LNM while 42 patients (41.2%) were free of LNM. TBR(without LNM: 6.9 ± 3.6 vs. LNM: 8.2 ± 2.9, P = 0.019), CA19-9(506.9 ± 1602.7 vs. 1901.2 ± 3195.1, P = 0.011) and CEA(5.1 ± 8.9 vs. 32.5 ± 82.7, P = 0.035) in the LNM group were significantly higher than in the without LNM group. Three additional, statistically significant features, tumor TBR > 6.4, CA19-9 > 149.7 U/mL and CEA > 3.2 ng/mL, were integrated into a prediction model, which substantially outperformed use of the single parameter in ROC analysis (AUC 0.802 vs. 0.676, 0.671 and 0.656).</p><p><strong>Conclusion: </strong>TBR > 6.4 and CA19-9 > 149.7 U/mL were identified as effective preoperative predictors of LNM in patients with ICC. The prognostic model we propose, integrating imaging parameters and serological indicators, significantly enhances predictive capability.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147434237","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":"Photoacoustic Imaging of Muscle Tissue Oxygenation as a Noninvasive Biomarker in Mouse Models of Sickle Cell Disease.","authors":"Jeffrey Morin, Megan Brophy, John Stansfield, Debra Pittman, Dinesh Hirenallur-Shanthappa","doi":"10.1007/s11307-026-02095-8","DOIUrl":"https://doi.org/10.1007/s11307-026-02095-8","url":null,"abstract":"<p><strong>Purpose: </strong>To develop and validate photoacoustic imaging (PAI) as a method to assess hemoglobin counts and muscle tissue oxygen saturation in a mouse model of Sickle Cell Disease (SCD.</p><p><strong>Procedures: </strong>In vivo PAI was performed on mice with a SCD phenotype and results were compared to those from animals carrying a homozygous knockout of Bisphosphoglycerate mutase (BPGM), meant to annul the SCD phenotype, as well as controls (129 strain), then further compared to sickling assay results of blood collected from the same mice.</p><p><strong>Results: </strong>PAI of the hindlimb muscles of SCD mice demonstrated significant decrease in tissue oxygen saturation (sO2) compared to control mice (28.4% vs 35.5%). Further PAI of mice with a genetic knock out of BPGM on an SCD background revealed tissue sO2 significantly greater (32.6%) than SCD mice and close to those in controls. These results correlate well with standard measurements of RBC sickling via cell counts. Hemoglobin counts derived from PAI further confirm the reduced tissue oxygen saturation measurements in SCD mice.</p><p><strong>Conclusions: </strong>PAI synergizes the specificity of optical imaging with the depth penetration capability of ultrasound to measure tissue oxygen saturation at deeper levels of tissue. The results of this study suggest this imaging method can be used to non-invasively measure hemoglobin counts and tissue oxygen levels as in vivo biomarkers in preclinical models of SCD, and potentially in the clinic as well.</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147434298","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":"Malignant Pleural Mesothelioma (MPM) Evaluation with [¹¹C]-Methionine PET/CT Before and After Talc Pleurodesis.","authors":"Egesta Lopci, Angelo Castello, Alberto Testori, Emanuele Voulaz, Daoud Rahal, Matteo Perrino, Alessandro Crepaldi, Giorgio Maria Ferraroli, Valentina Errico, Edoardo Bottoni, Marcello Rodari, Lorenzo Muraglia, Giuseppe Marulli, Marco Alloisio, Paolo Andrea Zucali","doi":"10.1007/s11307-026-02093-w","DOIUrl":"https://doi.org/10.1007/s11307-026-02093-w","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Malignant pleural mesothelioma (MPM) poses an imaging challenge that requires special attention, especially in patients who have undergone talc pleurodesis. [&lt;sup&gt;18&lt;/sup&gt;F]FDG PET/CT (FDG PET) is a validated imaging modality in oncology that has proven useful for detecting malignant pleural lesions. However, the inflammatory reaction induced by pleurodesis renders its interpretation unreliable. In this study, we assessed in parallel the role of [&lt;sup&gt;11&lt;/sup&gt;C]Methionine PET/CT (MET PET) and FDG PET in MPM patients before and after talc pleurodesis.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Materials and methods: &lt;/strong&gt;We prospectively enrolled 30 consecutive patients with clinical suspicion of MPM who were referred to our Institution from September 2014 to February 2016 for talc pleurodesis. The study was approved and registered at ClinicalTrials.gov (NCT02519049). Patients underwent assessment at baseline and after pleurodesis with two consecutive scans: FDG PET (standard imaging) and MET PET (experimental imaging). Semi-quantitative parameters were defined for both scans and statistically compared to pathological findings from video-assisted thoracoscopy (VATS), including SUVmax, SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis for FDG PET or metabolic tumor burden (TLG or MTB = MTV x SUVmean) for MET PET.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Twenty patients (M:F = 18:2; median age, 72 years) with MPM (18 epithelioid, 2 non-epithelioid) completed all study investigations. All tumors showed increased uptake of both FDG and MET PET. After talc pleurodesis, FDG PET showed a significant increase in mean and median MTV (P = 0.0005 and 0.0003, respectively) and mean and median TLG (P = 0.0172 and 0.0028, respectively). In contrast, MET PET parameters showed significant increases in mean and median SUVmax (P = 0.0208 and 0.0209, respectively) and SUVmean (P = 0.0106 and 0.0109, respectively) compared to baseline. There was a significant negative correlation between SUVmax, MTV and MTB/TLG and the percentage change at the early assessment post-pleurodesis for both MET PET (rho = -0.645, P &lt; 0.01; rho = -0.517, P = 0.013; rho = -0.528, P = 0.011, respectively) and FDG PET (rho = -0.808, P &lt; 0.01; rho = -0.781, P &lt; 0.01; rho = -0.888, P &lt; 0.01, respectively). The percentage change in SUVmax was significantly greater in FDG PET than for MET PET (+ 19% vs + 16%, P = 0.03). Additionally, mean and median MTV were significantly higher on FDG PET than MET PET (mean + 1022.3 vs + 224.2, P = 0.01; median + 157.5 vs + 7.1, P = 0.02).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;This study confirms the impact of talc pleurodesis on FDG PET, particularly for volumetric parameters (MTV and TLG). MET PET appears less influenced by post-pleurodesis inflammatory reaction than FDG PET, with changes mostly limited to SUVmax and SUVmean. Clinical Trial Number (NCT02519049) at the Clinical Trial Registry ( https://www.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Clinicaltrials: &lt;/strong&gt;gov","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147390526","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":"Design of a Bifunctional pHLIP-RGD Scaffold for Site-Specific [^99mTc] Tc Labeling: Radiochemical Evaluation and Proof-of-Concept Tumor Targeting.","authors":"Mingming Yu, Yuehua Chen, Bangxu Yu, Xia Li, Yuan Su, Zhenguang Wang","doi":"10.1007/s11307-026-02091-y","DOIUrl":"https://doi.org/10.1007/s11307-026-02091-y","url":null,"abstract":"<p><strong>Purpose: </strong>To develop a novel molecular scaffold designed for dual targeting via site-specific [^99mTc] Tc labeling, we report its radiochemical evaluation and preliminary targeting efficacy in acidic tumor models.</p><p><strong>Procedures: </strong>The pHLIP-RGD scaffold was synthesized by conjugating pHLIP variant 7 (var7) with cyclo(RGDfK) peptide. Pharmacokinetic assessment of [^99mTc] Tc-pHLIP-RGD was performed in MDA-MB-231 xenograft-bearing mice through quantitative biodistribution studies and small-animal single photon emission computed tomography (SPECT) imaging.</p><p><strong>Results: </strong>[^99mTc] Tc-pHLIP-RGD demonstrated high stability in mouse serum for at least 4 h and exhibited strong binding affinity and specificity both in vitro and in vivo. Biodistribution studies revealed rapid tumor accumulation and prolonged retention, with uptake values of 7.01 ± 1.28, 4.23 ± 0.44, 8.04 ± 0.63, and 9.60 ± 1.26%ID/g at 0.5, 1.0, 2.0, and 4.0 h post-injection, respectively. Off-target accumulation was primarily observed in the liver. In blocking studies, the administration of non-radioactive pHLIP-RGD partially reduced tumor uptake of [^99mTc] Tc-pHLIP-RGD, with tumor distribution values at 0.5, 1.0, 2.0, and 4.0 h of 4.66 ± 0.49, 3.25 ± 0.36, 3.04 ± 1.15, and 3.75 ± 0.57%ID/g, respectively. SPECT imaging findings were consistent with biodistribution data, showing clear visualization of tumors at all time points. Tumor visibility was significantly reduced in the blocking study, with a corresponding increase in liver uptake.</p><p><strong>Conclusions: </strong>The heterodimeric radiotracer [^99mTc] Tc-pHLIP-RGD exhibited high radiochemical yield, good stability, and favorable tumor uptake and retention characteristics. These proof-of-concept results suggest the potential of the dual-targeting design strategy for developing diagnostic imaging agents for triple-negative breast cancer (TNBC).</p>","PeriodicalId":18760,"journal":{"name":"Molecular Imaging and Biology","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147355811","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}