Search Results (17)

Cancer remains one of the leading causes of morbidity and mortality worldwide despite advances in molecular oncology and targeted therapeutics. The growing demand for precision medicine has accelerated the development of radiotheranostics, an emerging paradigm that integrates molecular imaging and targeted radionuclide therapy. In parallel, medicinal chemistry continues to generate structurally diverse small-molecule scaffolds capable of modulating key oncogenic pathways. Increasing evidence indicates that certain chemical scaffolds possess intrinsic properties that extend beyond conventional anticancer activity and support their translation into radiotheranostic applications. This review examines major scaffold classes driving contemporary anticancer drug discovery, including thiosemicarbazones, heterocyclic compounds, metal-based agents, hybrid molecules, and multifunctional platforms. Particular attention is given to the structural features governing biological activity, target selectivity, metal coordination, and radiolabeling potential. The review further highlights the mechanistic convergence between scaffold-mediated anticancer effects and radionuclide-induced cytotoxicity, emphasizing shared pathways involving DNA damage, oxidative stress, inhibition of DNA repair, and modulation of oncogenic signaling. Based on these observations, a scaffold-centered framework for radiotheranostic development is proposed, with perspectives on hybrid molecular design, copper-based theranostic systems, and artificial intelligence-assisted ligand discovery. By integrating medicinal chemistry, molecular oncology, and nuclear medicine, this review outlines structural principles that may facilitate the rational design of next-generation precision anticancer agents and radiotheranostic platforms. Full article

Fibroblast activation protein (FAP) has emerged as a promising target for the development of cancer radiotheranostics due to its selective overexpression in cancer-associated fibroblasts (CAFs) within the tumor stroma. Affinity and selectivity refer to the binding affinities of FAP inhibitors toward FAP and related family members, whereas the accumulation of radiolabeled-FAP inhibitors varies by tumor type. Although monomeric FAP inhibitors (FAPIs) have shown extraordinary utility in diagnostic imaging, their clinical application in radiotherapy has been limited by short tumor retention times and heterogeneous uptake. To address these challenges, homomultimeric FAPI ligands—featuring two or more identical FAP-targeting motifs—have been developed with the aim of enhancing binding avidity and prolonging tumor residence. This review comprehensively examines the evolution of homomultimeric FAPI ligands, from molecular design and preclinical validation to early clinical implementation. We highlight how dimeric and higher-order multimeric constructs improve tumor retention and therapeutic efficacy compared to monomers, while also discussing the impact of linker chemistry, valency, and scaffold architecture on pharmacokinetics and targeting efficiency. Preclinical studies demonstrate that optimized dimers and trimers achieve superior tumor-to-background ratios and sustained tumor uptake, whereas excessive multimerization can lead to steric hindrance and reduced efficacy. Clinical data from pioneering studies using agents such as [¹⁷⁷Lu]Lu-DOTAGA.(SA.FAPi)₂ and [¹⁷⁷Lu]Lu-DOTAGA.Glu.(FAPi)₂ confirm prolonged tumor retention, encouraging therapeutic responses and a favorable safety profile in advanced cancers. However, translational challenges remain, including the need for better preclinical models that reflect stromal FAP heterogeneity, optimized radiometal–chelator pairs, and standardized dosing protocols for comparative clinical trials. Overall, homomultimeric FAPI ligands represent a significant advance in FAP-targeted theranostics, offering a robust platform for personalized cancer management. Full article

Radiopharmaceutical Theranostics defines the combination of molecularly targeted imaging and therapy in two consecutive phases. Targeted theranostic approaches are most established for the management of advanced prostate, thyroid and hepatocellular cancer, as well as neuroendocrine tumors (NETs). Adrenal malignancies present a complex challenge, requiring highly specialized management. The two primary entities addressed by targeted radiotheranostics—pheochromocytoma/paraganglioma (PPGL) and adrenocortical cancer (ACC)—consist of fundamentally distinct molecular targets and, consequently, different radiopharmaceutical agents. While most existing literature focuses on nuclear medicine–driven perspectives, the implications of theranostic advances for surgical decision-making remain underexplored. This narrative review aims to integrate available clinical evidence with multidisciplinary practice considerations, in reshaping the role of surgery in adrenal malignancies. Full article

Despite significant progress in targeted cancer therapies and conventional imaging methodologies, the effective detection and treatment of solid tumours remain a major clinical challenge. This is thought to be caused by the complexity and heterogeneity found in the tumour microenvironment (TME), which significantly effects drug delivery and therapeutic response. Different levels of fibrosis, varying immune-cell infiltration, and disorganized vasculature form barriers for therapeutic approaches. However, in the next decade, radiotheranostics, defined here as the combined use of matched diagnostic and therapeutic radiopharmaceuticals, could present a targeted and flexible strategy for addressing some of the challenges caused by the TME. By combining molecular imaging with therapeutic delivery, it enables the in vivo visualization of TME features and the selective treatment of tumour and stromal compartments. This provides the unique opportunity to target tumour regions resistant to conventional therapies, including those shaped by (extracellular matrix) ECM stiffness, immune infiltration, or hypoxia. However, new strategies are needed to identify targets and evaluate their efficacy for more precise therapies. In this review, we will discuss why radiotheranostics is an ideal field for advancing the therapeutic approaches to solid tumours by incorporating the growing understanding of the TME. We will discuss how key microenvironmental features affect radiotracer distribution and treatment outcomes. We will highlight emerging tools including ECM- and immune-targeted imaging, patient-derived organoids, and organ-on-chip models which will be instrumental in developing physiologically relevant radiopharmaceutical therapies. Finally, we will discuss how spatial/single-cell transcriptomic approaches can support target discovery and allow for patient outcome assessment, with the aim of integrating microenvironment-aware insights into the development of novel radiotheranostic agents. Full article

Prostate cancer (PCa), particularly in its metastatic form, remains a major clinical challenge due to limited diagnostic and therapeutic options. To address this, we developed a novel radiotheranostic agent, [⁶⁴Cu]Cu-NOTA-TP-PSMA, by conjugating a prostate-specific membrane antigen (PSMA) ligand to a ⁶⁴Cu-radiolabeled terpyridine-platinum (TP) compound previously shown to exert selective cytotoxicity against cancer cells. In this study, the biological performance of [⁶⁴Cu]Cu-NOTA-TP-PSMA was compared with the monomeric analogs [⁶⁴Cu]Cu-NOTA-PSMA and [⁶⁴Cu]Cu-NOTA-TP through in vitro studies in PSMA-positive LNCaP prostate cancer cells and non-malignant HEK-293 cells. [⁶⁴Cu]Cu-NOTA-TP-PSMA showed high stability, PSMA binding affinity and exhibited substantially enhanced uptake, internalization, retention, and nuclear localization in LNCaP cells relative to the monomers, whereas uptake and nuclear accumulation in HEK-293 cells were negligible. Cytotoxicity assays further demonstrated potent and selective activity in LNCaP cells, with EC₅₀ values in the low nanomolar range, and minimal toxicity in HEK-293 cells. Collectively, these results identify [⁶⁴Cu]Cu-NOTA-TP-PSMA as a promising radiotheranostic agent, warranting further in vivo evaluation for prostate cancer imaging and targeted radiotherapy. Full article

Alpha therapy (TAT) relies on combining alpha-emitting radionuclides with specific cell-targeting vectors to deliver a high payload of cytotoxic radiation capable of destroying tumor tissues. TAT efficacy comes from the tissue selectivity of the targeting vector, the high linear energy transfer (LET) of the radionuclide, and the short range of alpha particles in tissues. Recent research studies have been directed to evaluate TAT on a preclinical and clinical scale, including evaluating damage to tumor tissues with minimal toxic radiation effects on surrounding healthy tissues. This review highlights the use of Actinium-225/Bismuth-213 radionuclides as promising candidates for TAT. Herein, we begin with a discussion on the production and supply of [²²⁵Ac]Ac/[²¹³Bi]Bi followed by the formulation of [²²⁵Ac]Ac/[²¹³Bi]Bi-radiopharmaceuticals using different radiolabeling techniques. Finally, we have summarized the preclinical and clinical evaluation of these potential radiotheranostic agents. Full article

Glioblastoma multiforme (GBM) remains one of the most aggressive and treatment-resistant brain tumors, with poor prognosis and limited therapeutic options. Background/Objectives: Integrin α_vβ₃, a cell surface receptor overexpressed in GBM, specifically binds to cyclic arginine-glycine-aspartate-D-phenylalanine-lysine (c(RGDfK)) motif, making it a valuable target for tumor-specific delivery and PET imaging. This study explores a novel radiotheranostic agent, [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK), which combines the imaging and therapeutic capabilities of copper-64 (⁶⁴Cu) and the cytotoxic activity of a terpyridine-platinum (TP) complex, conjugated to c(RGDfK). Methods: A robust protocol was developed for the small-scale preparation of NOTA-TP-c(RGDfK). Comparative cellular studies were conducted using U87 MG glioblastoma (GBM) cells and SVG p12 human astrocytes to evaluate the performance of [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK) relative to [⁶⁴Cu]Cu-NOTA-c(RGDfK), [⁶⁴Cu]Cu-NOTA-TP, ^natCu-NOTA-TP-c(RGDfK), cisplatin, and temozolomide. Results: ⁶⁴Cu-radiolabeling of NOTA-TP-c(RGDfK) was achieved with >99% radiochemical purity, and competition assays confirmed high binding affinity to integrin α_vβ₃ (IC₅₀ = 16 ± 8 nM). Cellular uptake, internalization, and retention studies demonstrated significantly higher accumulation of [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK) in U87 MG cells compared to control compounds, with 38.8 ± 1.8% uptake and 28.0 ± 1.0% internalization at 24 h. Nuclear localization (6.0 ± 0.5%) and stable intracellular retention further support its therapeutic potential for inducing localized DNA damage. Importantly, [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK) exhibited the highest cytotoxicity in U87 MG cells (IC₅₀ = 10 ± 2 nM at 48 h), while maintaining minimal toxicity in normal SVG p12 astrocytes. Conclusions: These results highlight [⁶⁴Cu]Cu-NOTA-TP-c(RGDfK) as a promising targeted radiotheranostic agent for GBM, warranting further preclinical development Full article

Albumin-binding agents enhance tumor uptake of radiopharmaceuticals targeting prostate-specific membrane antigens (PSMAs) in radiotherapy. We synthesized PSMA-NARI-56, a molecule with both PSMA targeting activity and albumin-binding moiety, labeled with ¹⁷⁷Lu as the therapeutic agent. The aim of this study was to determine the specific binding of ¹⁷⁷Lu-PSMA-NARI-56 towards PSMA, assess its biodistribution, and evaluate therapeutic effectiveness by tumor-bearing mice. The effect of ¹⁷⁷Lu-PSMA-NARI-56 viability of PSMA-positive cell (LNCaP) was evaluated. Biodistribution and endoradiotherapy studies were utilized to determine the distribution, targeting, and anti-tumor efficacy by tumor-bearing mice identified by ¹¹¹In-PSMA-NARI-56. ¹⁷⁷Lu-PSMA-NARI-56 exhibited a significant impact on the viability of the LNCaP cell. Biodistribution results revealed the maximum tumor uptake of ¹⁷⁷Lu-PSMA-NARI-56 occurring within 24 h, reaching 40.56 ± 10.01%ID/g. In radionuclide therapy, at 58 days post-injection (p.i.), ¹⁷⁷Lu-PSMA-NARI-56 demonstrated superior tumor inhibition (98%) compared to ¹⁷⁷Lu-PSMA-617 (58%), and the mouse survival rate after 90 days of radiotherapy (90%) was also higher than that of ¹⁷⁷Lu-PSMA-617 (30%) in LNCaP tumor-bearing mice. In the PSMA-positive animal model, ¹⁷⁷Lu-PSMA-NARI-56 shows higher potential radiotheranostic and prolonged accumulation (identify by ¹¹¹In-PSMA-NARI-56/nanoSPECT/CT image), offering the potential for improved treatment effectiveness and increased survival rates when compared to ¹⁷⁷Lu-PSMA-617. Full article

Prostate cancer, a malignancy of significant prevalence, affects approximately half a million men in Europe, with one in twelve males receiving a diagnosis before reaching the age of 75. Radiotheranostics represents a paradigm shift in prostate cancer treatment, leveraging radionuclides for diagnostic and therapeutic applications, with PSMA emerging as the primary molecular target. Regulatory bodies have approved various PSMA-targeted radiodiagnostic agents, such as [¹⁸F]DCFPyL (PYLARIFY^®, Lantheus Holdings), [¹⁸F]rhPSMA-7.3 (POSLUMA^®, Blue Earth Diagnostics), and [⁶⁸Ga]Ga-PSMA-11 (LOCAMETZ^®, Novartis/ILLUCCIX^®, Telix Pharmaceuticals), as well as therapeutic agents like [¹⁷⁷Lu]Lu-PSMA-617 (PLUVICTO^®, 15 Novartis). The approval of PLUVICTO^® in March 2022 for patients with metastatic castration-resistant prostate cancer who have undergone prior treatments, including androgen receptor pathway-targeting agents and taxane-based chemotherapy, represents a significant advancement. Other radionuclides like ¹⁶¹Tb, ¹⁴⁹Tb, ²²⁵Ac, ²²⁷Th, ²²³Ra, ²¹¹At, ²¹³ Bi, ²¹²Pb, ⁸⁹Zr, and ¹²⁵I are presented, emphasizing their clinical implementation or the stage of clinical trial they are in in the flow to biomedical implementation. Three clinically wise used radionuclides ¹⁷⁷Lu, ²²⁵Ac, ²²³Ra are shown along with their characteristics. This review aims to elucidate the molecular mechanisms underpinning PSMA, explore the clinical applications of PSMA-targeted radiotheranostics, and critically examine the diverse challenges these therapies encounter in the treatment of prostate cancer. Full article

Background: Fibroblast activation protein (FAP)-targeted theranostic radiopharmaceuticals have shown desired tumor-to-background organ selectivity due to the ubiquitous presence of FAP within the tumor microenvironment. However, suboptimal tumor retention and fast clearance have hindered their use to deliver effective cancer therapies. With well-documented FAP-targeting moieties and linkers appending them to optimal chelators, the development of copper radiopharmaceuticals has attracted considerable interest, given the fact that an ideal theranostic pair of copper radionuclides (⁶⁴Cu: t_1/2 = 12.7 h; 17.4% β⁺; E_β⁺_max = 653 keV and ⁶⁷Cu: t_1/2 = 2.58 d; 100% β⁻; E_β⁻_max = 562 keV) are available. Herein, we report our design, synthesis, and comparative evaluation of monovalent and divalent FAP-targeted theranostic conjugates constructed from our previously reported bifunctional chelator scaffold (BFS) based on 1,4,8,11-tetraaza-bicyclo [6.6.2]hexadecane-4,11-diacetic acid (CB-TE2A), which forms the most stable complex with Cu(II). Methods: After synthesis and characterization, the monovalent and divalent conjugates were radiolabeled with ⁶⁴Cu for in vitro cell assays, followed by in vivo positron emission tomography (PET) imaging evaluation in relevant mouse models. Results: Both ⁶⁴Cu-labeled conjugates showed high in vitro stability and anticipated FAP-mediated cell binding and internalization. The divalent one showed significantly higher FAP-specific tumor uptake than its monovalent counterpart. Conclusions: Our results demonstrate that the BFS-based multivalent approach can be practically used to generate FAP-targeted radiotheranostic agents for effective cancer diagnosis and treatment. Full article

Bifunctional chelators (BFCs) are a key element in the design of radiopharmaceuticals. By selecting a BFC that efficiently complexes diagnostic and therapeutic radionuclides, a theranostic pair possessing almost similar biodistribution and pharmacokinetic properties can be developed. We have previously reported 3p-C-NETA as a promising theranostic BFC, and the encouraging preclinical outcomes obtained with [¹⁸F]AlF-3p-C-NETA-TATE led us to conjugate this chelator to a PSMA-targeting vector for imaging and treatment of prostate cancer. In this study, we synthesized 3p-C-NETA-ePSMA-16 and radiolabeled it with different diagnostic (¹¹¹In, ¹⁸F) and therapeutic (¹⁷⁷Lu, ²¹³Bi) radionuclides. 3p-C-NETA-ePSMA-16 showed high affinity to PSMA (IC₅₀ = 4.61 ± 1.33 nM), and [¹¹¹In]In-3p-C-NETA-ePSMA-16 showed specific cell uptake (1.41 ± 0.20% ID/10⁶ cells) in PSMA expressing LS174T cells. Specific tumor uptake of [¹¹¹In]In-3p-C-NETA-ePSMA-16 was observed up to 4 h p.i. (1.62 ± 0.55% ID/g at 1 h p.i.; 0.89 ± 0.58% ID/g at 4 h p.i.) in LS174T tumor-bearing mice. Only a faint signal could be seen at 1 h p.i. in the SPECT/CT scans, whereas dynamic PET/CT scans performed after administration of [¹⁸F]AlF-3p-C-NETA-ePSMA-16 in PC3-Pip tumor xenografted mice resulted in a better tumor visualization and imaging contrast. Therapy studies with short-lived radionuclides such as ²¹³Bi could further elucidate the therapeutic potential of 3p-C-NETA-ePSMA-16 as a radiotheranostic. Full article

A paradigm shift is underway in cancer diagnosis and therapy using radioactivity-based agents called radiopharmaceuticals. In the new strategy, diagnostic imaging measures the tumor uptake of radioactive agent “X” in a patient’s specific cancer, and if uptake metrics are realized, the patient can be selected for therapy with radioactive agent “Y”. The X and Y represent different radioisotopes that are optimized for each application. X–Y pairs are known as radiotheranostics, with the currently approved route of therapy being intravenous administration. The field is now evaluating the potential of intra-arterial dosing of radiotheranostics. In this manner, a higher initial concentration can be achieved at the cancer site, which could potentially enhance tumor-to-background targeting and lead to improved imaging and therapy. Numerous clinical trials are underway to evaluate these new therapeutic approaches that can be performed via interventional radiology. Of further interest is changing the therapeutic radioisotope that provides radiation therapy by β- emission to radioisotopes that also decay by α-particle emissions. Alpha (α)-particle emissions provide high energy transfer to the tumors and have distinct advantages. This review discusses the current landscape of intra-arterially delivered radiopharmaceuticals and the future of α-particle therapy with short-lived radioisotopes. Full article

Glioblastoma multiforme (GBM), the most common type of brain cancer, is extremely aggressive and has a dreadful prognosis. GBM comprises 60% of adult brain tumors and the 5 year survival rate of GBM patients is only 4.3%. Standard-of-care treatment includes maximal surgical removal of the tumor in combination with radiation and temozolomide (TMZ) chemotherapy. TMZ is the “gold-standard” chemotherapy for patients suffering from GBM. However, the median survival is only about 12 to 18 months with this protocol. Consequently, there is a critical need to develop new therapeutic options for treatment of GBM. Nanomaterials have unique properties as multifunctional platforms for brain tumor therapy and diagnosis. As one of the nanomaterials, lipid-based nanocarriers are capable of delivering chemotherapeutics and imaging agents to tumor sites by enhancing the permeability of the compound through the blood–brain barrier, which makes them ideal for GBM therapy and imaging. Nanocarriers also can be used for delivery of radiosensitizers to the tumor to enhance the efficacy of the radiation therapy. Previously, high-atomic-number element-containing particles such as gold nanoparticles and liposomes have been used as radiosensitizers. SapC–DOPS, a protein-based liposomal drug comprising the lipid, dioleoylphosphatidylserine (DOPS), and the protein, saposin C (SapC), has been shown to be effective for treatment of a variety of cancers in small animals, including GBM. SapC–DOPS also has the unique ability to be used as a carrier for delivery of radiotheranostic agents for nuclear imaging and radiotherapeutic purposes. These unique properties make tumor-targeting proteo-liposome nanocarriers novel therapeutic and diagnostic alternatives to traditional chemotherapeutics and imaging agents. This article reviews various treatment modalities including nanolipid-based delivery and therapeutic systems used in preclinical and clinical trial settings for GBM treatment and detection. Full article

Neuroblastoma (NB) represents the most common extracranial tumor of childhood. Prognosis is quite variable, ranging from spontaneous regression to aggressive behavior with wide metastatization, high mortality, and limited therapeutic options. Radiotheranostics combines a radiopharmaceutical pair in a unique approach, suitable both for diagnosis and therapy. For many years, metaiodobenzylguanidine (MIBG), labeled with ¹²³I for imaging or ¹³¹I for therapy, has represented the main theranostic agent in NB, since up to 90% of NB incorporates the aforementioned radiopharmaceutical. In recent years, novel theranostic agents hold promise in moving the field of NB radiotheranostics forward. In particular, SarTATE, consisting of octreotate targeting somatostatin receptors, has been applied with encouraging results, with ⁶⁴Cu-SARTATE being used for disease detection and with ⁶⁷Cu-SARTATE being used for therapy. Furthermore, recent evidence has highlighted the potential of targeted alpha therapy (TAT) for treating cancer by virtue of alpha particles’ high ionizing density and high probability of killing cells along their track. On this path, ²¹¹At-astatobenzylguanidine (MABG) has been developed as a potential agent for TAT and is actually under evaluation in preclinical NB models. In this review, we performed a web-based and desktop literature research concerning radiotheranostic approaches in NB, covering both the radiopharmaceuticals already implemented in clinical practice (i.e.,¹²³/¹³¹1-MIBG) and those still in a preliminary or preclinical phase. Full article

Novel 6-bromo-coumarin-ethylidene-hydrazonyl-thiazolyl and 6-bromo-coumarin-thiazolyl-based derivatives were synthesized. A quantitative structure activity relationship (QSAR) model with high predictive power r² = 0.92, and RMSE = 0.44 predicted five compounds; 2b, 3b, 5a, 9a and 9i to have potential anticancer activities. Compound 2b achieved the best ΔG of –15.34 kcal/mol with an affinity of 40.05 pki. In a molecular dynamic study 2b showed an equilibrium at 0.8 Å after 3.5 ns, while flavopiridol did so at 0.5 Å after the same time (3.5 ns). 2b showed an IC₅₀ of 0.0136 µM, 0.015 µM, and 0.054 µM against MCF-7, A-549, and CHO-K1 cell lines, respectively. The CDK4 enzyme assay revealed the significant CDK4 inhibitory activity of compound 2b with IC₅₀ of 0.036 µM. The selectivity of the newly discovered lead compound 2b toward localization in tumor cells was confirmed by a radioiodination biological assay that was done via electrophilic substitution reaction utilizing the oxidative effect of chloramine-t. ¹³¹I-2b showed good in vitro stability up to 4 h. In solid tumor bearing mice, the values of tumor uptake reached a height of 5.97 ± 0.82%ID/g at 60 min p.i. ¹³¹I-2b can be considered as a selective radiotheranostic agent for solid tumors with promising anticancer activity. Full article