Synthesis and Evaluation of [64Cu]Cu-NOTA-HFn for PET Imaging of Transferrin Receptor 1 Expression in Nasopharyngeal Carcinoma.

As recurrent and metastatic nasopharyngeal carcinoma (NPC) is the most common cause of death among patients with NPC, there is an urgent clinical need for the development of precision diagnosis to guide personalized treatment. Recent emerging evidence substantiates the increased expression of transferrin receptor 1 (also known as cluster of differentiation 71, CD71) within tumor tissues and the inherent targeting capability of natural heavy-chain ferritin (HFn) toward CD71. This study aimed to synthesize and assess a radiotracer ([64Cu]Cu-NOTA-HFn) designed to target CD71 for positron emission tomography (PET) imaging in an NPC tumor-bearing mouse model. The entire radiolabeling process of [64Cu]Cu-NOTA-HFn was completed within 15 min with high yield (>98.5%) and high molar activity (72.96 ± 21.33 GBq/µmol). The in vitro solubility and stability experiments indicated that [64Cu]Cu-NOTA-HFn had a high water solubility (log P = -2.42 ± 0.52, n = 6) and good stability in phosphate-buffered saline (PBS) for up to 48 h. The cell saturation binding assay indicated that [64Cu]Cu-NOTA-HFn had a nanomolar affinity (Kd = 10.9 ± 6.1 nM) for CD71-overexpressing C666-1 cells. To test the target engagement in vivo, prolonged-time PET imaging was performed at 1, 6, 12, 24, and 36 h postinjection (p.i.) of [64Cu]Cu-NOTA-HFn to C666-1 NPC tumor-bearing mice. The C666-1 tumors could be visualized by [64Cu]Cu-NOTA-HFn and blocked by nonradiolabeled HFn. PET imaging quantitative analysis demonstrated that the uptake of [64Cu]Cu-NOTA-HFn in C666-1 tumors peaked at 6 h p.i. and the best radioactive tumor-to-muscle ratio was 10.53 ± 3.11 (n = 3). Ex vivo biodistribution assay at 6 h p.i. showed that the tumor uptakes were 1.43 ± 0.23%ID/g in the nonblock group and 0.92 ± 0.2%ID/g in the block group (n = 3, p < 0.05). Immunohistochemistry and immunofluorescence staining confirmed positive expression of CD71 and the uptake of HFn in C666-1 tumor tissues. In conclusion, our experiments demonstrated that [64Cu]Cu-NOTA-HFn possesses a very high target engagement for CD71-positive NPC tumors and provided a fundamental basis for further clinical translation.

Prognostic significance and immunoinfiltration analysis of genes associated with epithelial-mesenchymal transition and energy metabolism in bladder urothelial carcinoma.

BACKGROUND: Epithelial-mesenchymal transition (EMT) and aberrant energy metabolism are pivotal biological processes in tumor progression, significantly impacting tumor prognosis. However, the relationship between EMT, energy metabolism, and the immune microenvironment in bladder urothelial carcinoma (BLCA) remains inadequately understood. METHODS: Bladder cancer samples from The Cancer Genome Atlas were categorized into two groups via clustering analysis to elucidate disparities in expression, prognostic significance, and immune infiltration of genes associated with EMT and energy metabolism between these groups. Key genes associated with EMT and energy metabolism in BLCA were identified through Cox multifactorial regression analysis, immune infiltration analysis, etc. Subsequently, their prognostic significance in BLCA was validated. RESULTS: Cluster analysis revealed significant differences in the expression of genes associated with EMT and energy metabolism between the two groups. Group 2 exhibited significantly improved overall survival and progression-free survival compared to Group 1. Chondroitin sulfate proteoglycan 4 (CSPG4) emerged as the most critical gene associated with EMT, energy metabolism, prognosis, and immune infiltration in BLCA. Immunohistochemical assays demonstrated differential expression of CSPG4 in bladder tumors and normal bladder tissues, with high CSPG4 expression correlating with a poorer BLCA prognosis. Furthermore, CSPG4 exhibited an association with the immune checkpoint molecule programmed death-1 (PD1) in BLCA. CONCLUSIONS: EMT and energy metabolism exert pivotal influences on the immune microenvironment in BLCA. CSPG4 holds promise as a prognostic biomarker for patients with BLCA, offering valuable insights into potential immunotherapeutic strategies for this patient population.

Senescence-related gene c-Myc affects bladder cancer cell senescence by interacting with HSP90B1 to regulate cisplatin sensitivity.

Patients with advanced bladder cancer gradually become less sensitive to chemotherapeutic agents, leading to tumor recurrence. Initiating the senescence program in solid tumors may be an important means of improving short-term drug sensitivity. The important role of c-Myc in bladder cancer cell senescence was determined using bioinformatics methods. The response to cisplatin chemotherapy in bladder cancer sample was analyzed according to the Genomics of Drug Sensitivity in Cancer database. Cell Counting Kit-8 assay, clone formation assay, and senescence-associated ß-galactosidase staining were used to assess bladder cancer cell growth, senescence, and sensitivity to cisplatin, respectively. Western blot and immunoprecipitation were performed to understand the regulation of p21 by c-Myc/HSP90B1. Bioinformatic analysis showed that c-Myc, a cellular senescence gene, was significantly associated with bladder cancer prognosis and sensitivity to cisplatin chemotherapy. c-Myc and HSP90B1 expression were highly correlated in bladder cancer. Reducing the level of c-Myc significantly inhibited bladder cancer cell proliferation, promoted cellular senescence, and enhanced cisplatin chemosensitivity. Immunoprecipitation assays confirmed that HSP90B1 interacted with c-Myc. Western blot analysis showed that reducing the level of HSP90B1 could redeem the p21 overexpression caused by c-Myc overexpression. Further studies showed that reducing HSP90B1 expression could alleviate the rapid growth and accelerate cellular senescence of bladder cancer cells caused by c-Myc overexpression, and that reducing HSP90B1 levels could also improve cisplatin sensitivity in bladder cancer cells. HSP90B1/c-Myc interaction regulates the p21 signaling pathway, which affects cisplatin chemosensitivity by modulating bladder cancer cell senescence.

Yersinia enterocolitica in Crohn's disease.

Increasing attention is being paid to the unique roles gut microbes play in both physiological and pathological processes. Crohn's disease (CD) is a chronic, relapsing, inflammatory disease of the gastrointestinal tract with unknown etiology. Currently, gastrointestinal infection has been proposed as one initiating factor of CD. Yersinia enterocolitica, a zoonotic pathogen that exists widely in nature, is one of the most common bacteria causing acute infectious gastroenteritis, which displays clinical manifestations similar to CD. However, the specific role of Y. enterocolitica in CD is controversial. In this Review, we discuss the current knowledge on how Y. enterocolitica and derived microbial compounds may link to the pathogenesis of CD. We highlight examples of Y. enterocolitica-targeted interventions in the diagnosis and treatment of CD, and provide perspectives for future basic and translational investigations on this topic.

A Novel Nomogram Combined the Aggregate Index of Systemic Inflammation and PIRADS Score to Predict the Risk of Clinically Significant Prostate Cancer.

Background: This study is aimed at constructing a nomogram to predict the risk of clinically significant prostate cancer (csPCa) based on the aggregate index of systemic inflammation (AISI) and prostate imaging-reporting and data system version (PIRADS) score. Methods: Clinical data on patients who had undergone initial prostate biopsy from January 2019 to December 2021 were collected. Patients were randomized in a 7 : 3 ratio to the training cohort and the validation cohort. Potential risk factors for csPCa were identified by univariable and multivariate logistic regression. Nomogram was conducted with these independent risk factors, and calibration curves, the receiver operating characteristic (ROC), and decision curve analysis (DCA) were employed to assess the nomogram's ability for prediction. Results: A total of 1219 patients were enrolled in this study. Multivariate logistic regression identified that age, AISI, total prostatic specific-antigen (tPSA), free to total PSA (f/tPSA), prostate volume (PV), and PIRADS score were potential risk predictors of csPCa, and the nomogram was developed based on these factors. The area under the curve (AUC) of the training cohort and validation cohort was 0.884 (95% CI: 0.862-0.906) and 0.899 (95% CI: 0.867-0.931). The calibration curves showed that the apparent curves were closer to the ideal curves. The DCA results revealed that the nomogram model seemed to have clinical application value per DCA. Conclusion: The nomogram model can efficiently predict the risk of csPCa and may assist clinicians in determining if a prostate biopsy is necessary.

Enhancement mechanism of magnetite on the ball-milling destruction of perfluorooctane sulfonate by iron.

Zero-valent iron (Fe) is commonly employed as an additive for the mechanochemical destruction (MCD) of organic pollutants. The poly- and perfluoroalkyl substances (e.g., perfluorooctane sulfonate, PFOS) are a class of toxic environmental pollutants that are difficult to effectively degrade due to their thermodynamic and chemical stability. In this study, magnetite (Fe3O4) was applied to improve the milling performance of Fe to PFOS and its promoting mechanisms were emphatically explored. The desulfurization rate was in ahead of the defluorination rate because the C-S bond is less stable than the C-F bonds in PFOS. Fe3O4 had an excellent reinforcement effect on the milling performance of Fe, which was mainly through accelerating the electron transfer as a conductor, reacting with Fe to produce FeO, and facilitating the formation of HO●. During the MCD of PFOS with Fe/Fe3O4 as an additive, HO● played a dominant role in the defluorination process (accounting for >67%). After the elimination of sulfonate group (-SO3-), the produced radical (C7F15CF2●) continued to react through two main pathways: one was the stepwise defluorination after hydrogenation, and the other one was oxidation reaction after alcoholization to yield the corresponding aldehydes and carboxylic acids. The optimum Fe fraction (MFe) was 30%, and air atmosphere was more effective than oxygen and nitrogen conditions. This study helps to comprehensively understand the role of Fe3O4 in defluorination and fills the gap of Fe/Fe3O4 application in the MCD of PFASs.

Hetero-aryl bromide precursor fluorine-18 radiosynthesis and preclinical evaluation of a novel positron emission tomography (PET) tracer [18F]GSK1482160.

The purinergic P2X7 receptor (P2X7R), an ATP gated ion channel, is an important therapeutic target for various inflammatory immune and neurodegenerative diseases. A novel P2X7R targeting radiotracer GSK1482160 was radiosynthesized by hetero-aryl bromides precursor 10 with [18F]Et4NF, 20-30 % radiochemical yield, > 68 GBq/µmol specific activity, >98 % radiochemical purity. Evaluation in healthy male Sprague-Dawley rats revealed that [18F]GSK1482160 ([18F]11) was stably retained 87.81 %, 72.45 %, and 56.32 % in brain, blood and liver respectively 60-min post-injection. Ex-vivo biodistribution of [18F]11 proved that it was able to target the P2X7R in vivo and there was no defluorination in the major organs. PET/MRI imaging and autoradiography revealed that [18F]11 was able to penetrate the blood-brain barrier (BBB) and to be a promising P2X7R PET radioligand for clinical translation.

A Positron Emission Tomography Tracer Targeting the S2 Subunit of SARS-CoV-2 in Extrapulmonary Infections.

Tracking the pathogen of coronavirus disease 2019 (COVID-19) in live subjects may help estimate the spatiotemporal distribution of SARS-CoV-2 infection in vivo. This study developed a positron emission tomography (PET) tracer of the S2 subunit of spike (S) protein for imaging SARS-CoV-2. A pan-coronavirus inhibitor, EK1 peptide, was synthesized and radiolabeled with copper-64 after being conjugated with 1,4,7-triazacyclononane-1,4,7-triyl-triacetic acid (NOTA). The in vitro stability tests indicated that [64Cu]Cu-NOTA-EK1 was stable up to 24 h both in saline and in human serum. The binding assay showed that [64Cu]Cu-NOTA-EK1 has a nanomolar affinity (Ki = 3.94 ± 0.51 nM) with the S-protein of SARS-CoV-2. The cell uptake evaluation used HEK293T/S+ and HEK293T/S- cell lines that showed that the tracer has a high affinity with the S-protein on the cellular level. For the in vivo study, we tested [64Cu]Cu-NOTA-EK1 in HEK293T/S+ cell xenograft-bearing mice (n = 3) and pseudovirus of SARS-CoV-2-infected HEK293T/ACE2 cell bearing mice (n = 3). The best radioactive xenograft-to-muscle ratio (X/Nxenograft 8.04 ± 0.99, X/Npseudovirus 6.47 ± 0.71) was most evident 4 h postinjection. Finally, PET imaging in the surrogate mouse model of beta-coronavirus, mouse hepatic virus-A59 infection in C57BL/6 J mice showed significantly enhanced accumulation in the liver than in the uninfected mice (1.626 ± 0.136 vs 0.871 ± 0.086 %ID/g, n = 3, P < 0.05) at 4 h postinjection. In conclusion, our experimental results demonstrate that [64Cu]Cu-NOTA-EK1 is a potential molecular imaging probe for tracking SARS-CoV-2 in extrapulmonary infections in living subjects.

Multiple penile schwannomas.

Penile neoplasm is uncommon, and multiple penile schwannomas are even rarer. We report a case of a 37-year-old man with multiple schwannomas on the left side of the penis, which had been present for more than 10 years without significant enlargement during erection and had recently been associated with mild pain. Ultrasonography revealed several subcutaneous heterogeneous hypoechoic of penile, the larger of which was approximately 1.9 × 0.9 cm. The patient underwent penile mass excision, and pathology and immunohistochemistry confirmed that it was schwannoma. The patient was followed up for 3 years without recurrence or metastasis.

Determining nonesterified and total docosahexaenoic acid and eicosapenaenoic acid concentrations by LC-MS/MS in the plasma of patients with schizophrenia.

Background: Nonesterified, total docosahexaenoic acid (DHA) and eicosapenaenoic acid (EPA) plasma levels were evaluated in patients with schizophrenia on different medications compared with healthy individuals using validated LC-MS/MS methods. Methods: Samples for nonesterified DHA and EPA assay were extracted in n-hexane-dichloromethane-isopropyl alcohol (2:1:0.1, V/V/V) and hydrolyzed at 90°C for 2 h before total DHA and EPA determination. Methods were validated in surrogate matrix and plasma. Results: These methods generated similar recovery for plasma (>89%) and surrogate matrix (>87%) and negligible matrix effects. Linearity, lower limit of quantification, accuracy, precision and stability were also validated. Conclusions: This study successfully determined DHA and EPA plasma levels in patients with schizophrenia and healthy individuals using validated LC-MS/MS methods. Therefore, nonesterified DHA and total EPA levels could be used as schizophrenia biomarkers.