Iodinated gadolinium-gold nanomaterial as a multimodal contrast agent for cartilage tissue imaging.

Cartilage damage, a common cause of osteoarthritis, requires medical imaging for accurate diagnosis of pathological changes. However, current instruments can acquire limited imaging information due to sensitivity and resolution issues. Therefore, multimodal imaging is considered an alternative strategy to provide valuable images and analyzes from different perspectives.

Enhanced antitumour response of gold nanostar-mediated photothermal therapy in combination with immunotherapy in a mouse model of colon carcinoma.

Objectives: This study investigated the potential of combining PTT with dendritic cell (DC)-based immunotherapy and anti-PD-L1 immune checkpoint blockade (ICB) therapy against colorectal cancer and elucidated the underlying mechanisms.

Methods: The CT26 tumour-bearing mice were divided into seven treatment groups: control, atezolizumab (A), dendritic cells (DC), pAuNSs-mediated PTT (PTT), PTT combined with atezolizumab (PTT + A), PTT combined with dendritic cells (PTT + DC), and PTT combined with dendritic cells and atezolizumab (PTT + DC + A). Therapeutic efficacy was monitored.

Site-specific Conjugation of 6 DOTA Chelators to a CA19-9-targeting scFv-Fc Antibody for Imaging and Therapy.

Antibodies conjugated with diagnostic/therapeutic radionuclides are attractive options for inoperable cancers lacking accurate imaging methods and effective therapeutics, such as pancreatic cancer. Hence, we have produced an antibody radionuclide conjugate termed TE-1132 comprising a α-CA19-9 scFv-Fc that is site-specifically conjugated at each C-terminus to 3 DOTA chelators via a cysteine-containing peptide linker. The smaller scFv-Fc size facilitates diffusivity within solid tumors, whereas the chelator-to-antibody ratio of six enabled Lu-radiolabeled TE-1132 to exhibit high radioactivity up to 520 MBq/nmol.

PDT-active upconversion nanoheaters for targeted imaging guided combinatorial cancer phototherapies with low-power single NIR excitation.

A versatile nanoformulation is designed by anchoring human transferrin protein (Tf) on fluoromagnetic upconverting nanoheaters, NaGdF:Yb,Er (UCNP), loaded with Rose Bengal (RB), for multimodal imaging guided synergistic photothermal (PTT) and photodynamic therapy (PDT) at the targeted tumor site. The NIR excitation of the UCNP-RB Forster Resonance Energy Transfer (FRET) pair results in the reactive oxygen species (ROS) generation for PDT, whereas the non-radiative transitions in Er result in the heat required for PTT. The intravenously injected theranostic agent (UCNP@Tf-RB) enabled; (1) combinatorial PTT and PDT of 4T1 tumors with minimal systemic toxicity, (2) dual targeted (passive and active) tumor accumulation, (3) dual-modal imaging (MRI/photothermal), and, (4) excellent stability and biocompatibility.

Radiometal-Labeled Chitosan Microspheres as Transarterial Radioembolization Agents against Hepatocellular Carcinoma.

Transarterial radioembolization (TARE) is an emerging treatment for patients with unresectable hepatocellular carcinoma (HCC). This study successfully developed radiometal-labeled chitosan microspheres (111In/177Lu-DTPA-CMS) with a diameter of 36.5 ± 5.

Brachytherapy Approach Using Lu Conjugated Gold Nanostars and Evaluation of Biodistribution, Tumor Retention, Dosimetry and Therapeutic Efficacy in Head and Neck Tumor Model.

Brachytherapy can provide sufficient doses to head and neck squamous cell carcinoma (HNSCC) with minimal damage to nearby normal tissues. In this study, the β-emitter Lu was conjugated to DTPA-polyethylene glycol (PEG) decorated gold nanostars (Lu-DTPA-pAuNS) used in surface-enhanced Raman scattering and photothermal therapy (PTT). The accumulation and therapeutic efficacy of Lu-DTPA-pAuNS were compared with those of Lu-DTPA on an orthotopic HNSCC tumor model.

Automated Synthesis and Initial Evaluation of (4'-Amino-5',8'-difluoro-1'H-spiro[piperidine-4,2'-quinazolin]-1-yl)(4-[F]fluorophenyl)methanone for PET/MR Imaging of Inducible Nitric Oxide Synthase.

Background: Inducible nitric oxide synthase (iNOS) plays a crucial role in neuroinflammation, especially microglial activity, and may potentially represent a useful biomarker of neuroinflammation. In this study, we carefully defined a strategic plan to develop iNOS-targeted molecular PET imaging using (4'-amino-5',8'-difluoro-1'H-spiro[piperidine-4,2'-quinazolin]-1-yl)(4-fluorophenyl)methanone ([F]FBAT) as a tracer in a mouse model of lipopolysaccharide- (LPS-) induced brain inflammation.

Methods: An model, murine microglial BV2 cell line, was used to assess the uptake of [F]FBAT in response to iNOS induction at the cellular level.

Development of Radiofluorinated Nicotinamide/Picolinamide Derivatives as Diagnostic Probes for the Detection of Melanoma.

Regarding the increased incidence and high mortality rate of malignant melanoma, practical early-detection methods are essential to improve patients' clinical outcomes. In this study, we successfully prepared novel picolinamide-benzamide (F-FPABZA) and nicotinamide-benzamide (F-FNABZA) conjugates and determined their biological characteristics. The radiochemical yields of F-FPABZA and F-FNABZA were 26 ± 5% and 1 ± 0.

Evaluation of Radioiodinated Fluoronicotinamide/Fluoropicolinamide-Benzamide Derivatives as Theranostic Agents for Melanoma.

Malignant melanoma is the most harmful type of skin cancer and its incidence has increased in this past decade. Early diagnosis and treatment are urgently desired. In this study, we conjugated picolinamide/nicotinamide with the pharmacophore of I-MIP-1145 to develop I-iodofluoropicolinamide benzamide (I-IFPABZA) and I-iodofluoronicotiamide benzamide (I-IFNABZA) with acceptable radiochemical yield (40 ± 5%) and high radiochemical purity (>98%).

Investigation of biodistribution and tissue penetration of PEGylated gold nanostars and their application for photothermal cancer treatment in tumor-bearing mice.

Gold nanostars (AuNSs), with unique physicochemical properties, are thought to be a promising agent for photothermal therapy (PTT). In this study, we prepared PEGylated gold nanostars (pAuNSs) using the HEPES-reduction method. The high photothermal conversion efficiency (∼80%) and photothermal stability of pAuNSs were demonstrated in vitro and in vivo.

Presence of Gold Nanoparticles in Cells Associated with the Cell-Killing Effect of Modulated Electro-Hyperthermia.

The efficacy of gold nanoparticle (AuNP)-assisted radiofrequency (RF)-induced hyperthermia employing the Kanzius device remains controversial. Different from the Kanzius device, modulated electro-hyperthermia (mEHT) utilizes the capacitive-impedance coupled 13.56 MHz radiofrequency (RF) current and has been approved for clinical cancer treatment.

In Vivo and in Vitro Demonstration of Gold Nanorod Aided Photothermal Presoftening of B16F10 Melanoma for Efficient Chemotherapy Using Doxorubicin Loaded Graphene Oxide.

A combined photothermal therapy (PTT) and chemotherapy (chemo) were performed in vitro on B16F10 melanoma cells and in vivo using melanoma bearing C57BL/6 mice. The 785 nm (100 mW) irradiated gold nanorods (AuNRs) were used as the PT agent, and electrostatically conjugated Doxorubicin (Dox) to a nanocarrier graphene oxide (GO) worked as the chemotherapeutic. Selection of dosage was optimized from the individual viability studies, and finally a combined therapeutic (AuNR (100 ppm), GO (125, and 250 ppm), Dox (0.

Evaluation of the Biological Behavior of a Gold Nanocore-Encapsulated Human Serum Albumin Nanoparticle (Au@HSANP) in a CT-26 Tumor/Ascites Mouse Model after Intravenous/Intraperitoneal Administration.

Colorectal cancer is one of the major causes of cancer-related death in Taiwan and worldwide. Patients with peritoneal metastasis from colorectal cancer have reduced overall survival and poor prognosis. Hybrid protein-inorganic nanoparticle systems have displayed multifunctional applications in solid cancer theranostics.

Synthesis and biological evaluation of 2-(3,4-dimethoxyphenyl)-6-(2-[F]fluoroethoxy)benzothiazole ([F]FEDBT) for PET imaging of breast cancer.

Given the ever-present demand for improved PET radiotracer in oncology imaging, we have synthesized 2-(3,4-dimethoxyphenyl)-6-(2-[F]fluoroethoxy)benzothiazole ([F]FEDBT), a fluorine-18-containing fluoroethylated benzothiazole to explore its utility as a PET imaging tracer. [F]FEDBT was prepared via kryptofix-mediated nucleophilic substitution of the tosyl group precursor. Fractionated ethanol-based solid-phase (SPE cartridge-based) purification afforded [F]FEDBT in 60% radiochemical yield (EOB), with radiochemical purity in excess of 98% and the specific activity was 35GBq/μmol.

Preparation and characterization of a novel Al(18)F-NOTA-BZA conjugate for melanin-targeted imaging of malignant melanoma.

Melanin is an attractive target for the diagnosis and treatment of malignant melanoma. Previous studies have demonstrated the specific binding ability of benzamide moiety to melanin. In this study, we developed a novel (18)F-labeled NOTA-benzamide conjugate, Al(18)F-NOTA-BZA, which can be synthesized in 30min with a radiochemical yield of 20-35% and a radiochemical purity of >95%.

Synthesis and characterization of a novel radioiodinated phenylacetamide and its homolog as theranostic agents for malignant melanoma.

Melanin is an attractive target for the diagnosis and treatment of malignant melanoma. This study reports the preparation and biological characterizations of N-(2-(diethylamino)ethyl)-2-(3-(123/131)I-iodo-4- hydroxyphenyl)acetamide and N-(2-(diethylamino)ethyl)-3-(3-(123/131)I-iodo-4-hydroxyphenyl)propanamide (123/131)I-IHPA and 123/131I-IHPP) as novel melanin-specific theranostic agents. These two tracers were hydrophilic, exhibited good serum stability and high binding affinity to melanin.

Synthesis and evaluation of ¹²³/¹³¹I-Iochlonicotinamide as a novel SPECT probe for malignant melanoma.

Malignant melanoma expresses a highly aggressive metastasis. Early diagnosis of malignant melanoma is important for patient survival. Radiolabeled benzamides and nicotinamides have been reported to be attractive candidates for malignant melanoma diagnosis as they bind to melanin, a characteristic substance that displays in malignant melanoma, and show high tumor accumulation and retention.

Synthesis and biological evaluation of technetium-99m labeled galactose derivatives as potential asialoglycoprotein receptor probes in a hepatic fibrosis mouse model.

Two galactose derivatives, a monovalent (99m)Tc-MAMA-MGal galactoside and a divalent (99m)Tc-MAMA-DGal galactoside, were synthesized and radiolabeled in high radiochemical purity (>98%). Dynamic microSPECT imaging and biodistribution study of two traces in normal and liver fibrosis mice showed that the (99m)Tc-MAMA-DGal revealed higher specific binding to asialoglycoprotein receptors in liver and then rapidly excreted via both hepatobiliary system and renal clearance. The results suggest that (99m)Tc-MAMA-DGal may be used as SPECT probes for noninvasive evaluation of asialoglycoprotein receptor-related liver dysfunction.

Simultaneous imaging of temporal changes of NF-κB activity and viable tumor cells in Huh7/NF-κB-tk-luc2/rfp tumor-bearing mice.

Few studies have reported that the effect of sorafenib on advanced human hepatocellular carcinoma (HCC) is taking place via the inhibition of NF-κB signal transduction. Here we constructed a human HCC Huh7 stable clone with NF-κB-responsive element to drive dual reporter genes, herpes simplex virus thymidine kinase (tk) and firefly luciferase (luc2), and co-transfected with a third red fluorescent protein (rfp) gene, renamed as Huh7/NF-κB-tk-luc2/rfp cells, and combined with bioluminescent imaging (BLI) and red fluorescent protein imaging (RFPI) to monitor the effect of sorafenib on NF-κB activation and tumor inhibition. The results show that sorafenib could suppress the NF-κB-DNA binding activity, and the expression of downstream effector proteins.

Evaluation of (131/123)I-5-iodo-2'-deoxycytidine as a novel proliferation probe in a tumor mouse model.

This study evaluated a radioiodinated deoxycytidine analog, (131)I-5-iodo-2'-deoxycytidine ([(131)I]ICdR), as a novel proliferation probe and compared it with (131)I-5-iodo-2'-deoxyuridine ([(131)I]IUdR) in a NG4TL4 sarcoma-bearing mouse model. As an imaging agent, the biological characteristics of [(123)I]IUdR is not satisfactory due to its metabolic instability and short biological half-life in vivo. With [(123)I]ICdR/SPECT it was possible to clearly delineate the tumor lesion at 1h post-injection (tumor-to-muscle ratio 7.

The utilization of radionuclide myocardial perfusion imaging and cardiac catheterization under Taiwan's universal health insurance program.

This study examines the utilization patterns of myocardial perfusion imaging (MPI) and cardiac catheterization (CC) under Taiwan's national health insurance program. This study used the longitudinal health insurance database with 1,000,000 people were randomly selected from the national health insurance research database. This study obtained data from these patients with coronary artery disease (CAD) and comparison with the utilization of MPI or CC between 2005 and 2009.

Evaluation of dose distribution of molecular delivery after blood-brain barrier disruption by focused ultrasound with treatment planning.

The permeability of the blood-brain barrier (BBB) can be enhanced by focused ultrasound (FUS) in localized regions with applications of ultrasound contrast agent (UCA). The purpose of this study was to evaluate the dose distribution of Evans blue (EB) in the targeted brain by sonication with treatment strategy. FUS exposure was applied with an ultrasound frequency of 1 MHz, a 5% duty cycle and a repetition frequency of 1 Hz.

(18)F-FBHGal for asialoglycoprotein receptor imaging in a hepatic fibrosis mouse model.

Quantification of the expression of asialoglycoprotein receptor (ASGPR), which is located on the hepatocyte membrane with high-affinity for galactose residues, can help assess ASGPR-related liver diseases. A hepatic fibrosis mouse model with lower asialoglycoprotein receptor expression was established by dimethylnitrosamine (DMN) administration. This study developed and demonstrated that 4-(18)F-fluoro-N-(6-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)hexyl)benzamide ((18)F-FBHGal), a new (18)F-labeled monovalent galactose derivative, is an asialoglycoprotein receptor (ASGPR)-specific PET probe in a normal and a hepatic fibrosis mouse models.

Sorafenib sensitizes human colorectal carcinoma to radiation via suppression of NF-κB expression in vitro and in vivo.

Over-expression of transcription factor nuclear factor-κB (NF-κB) in the residual tumor after the treatment is often observed at the later period of cancer radiotherapy, results in tumor radioresistance and poor treatment outcome. In this study, we combined sorafenib, a multikinase inhibitor, with ionizing radiation to evaluate the therapeutic effect, and to elucidate the possible mechanism responsible for the radiosensitization of sorafenib on a human HT29/tk-luc colorectal carcinoma in vitro and in vivo. Clonogenic survival and cell cycle analysis were used to evaluate the cytotoxicity of sorafenib in vitro.

Evaluation of F-18-labeled 5-iodocytidine (18F-FIAC) as a new potential positron emission tomography probe for herpes simplex virus type 1 thymidine kinase imaging.

Objective: Herpes simplex virus type 1 thymidine kinase (HSV1-tk) gene in combination with radiolabeled nucleoside substrates is the most widely used reporter system. This study characterized 1-(2'-deoxy-2'-[(18)F]fluoro-β-D-arabinofuranosyl)-5-iodocytosine ((18)F-FIAC) as a new potential positron emission tomography (PET) probe for HSV1-tk gene imaging and compared it with 2'-deoxy-2'-[(18)F]fluoro-5-iodo-1-β-D-arabinofuranosyluracil ((18)F-FIAU) and 2'-deoxy-2'-[(18)F]fluoro-5-ethyl-1-β-D-arabinofuranosyluracil((18)F-FEAU) (thymidine analogues) in an NG4TL4-WT/STK sarcoma-bearing mouse model.

Methods: A cellular uptake assay, biodistribution study, radioactive metabolites assay and microPET imaging of NG4TL4-WT/STK tumor-bearing mice post administration of (18)F-FIAC, (18)F-FIAU and (18)F-FEAU were conducted to characterize the biological properties of these tracers.