Current Radiopharmaceuticals - Volume 17, Issue 4, 2024

Ovarian disease constitutes various types of endocrine disorders, such as polycystic ovarian syndrome (PCOS), ovarian cancer, premature ovarian failure, ovarian endometriosis, and ovarian cysts. The prevalence of ovarian-related diseases is highly vulnerable in the world. The utility of various drug delivery systems for ovarian diseases has resulted in varied success. Moreover, most of them lead to severe adverse effects and are incapable of ameliorating the signs and symptoms of the condition. Intrauterine devices (IUDs) have positioned themselves as a mechanism to deliver the drug for various ovarian-related diseases. Thereby avoiding various stability-related issues arising due to various physiological barriers of the female reproductive tract. However, the use of intrauterine devices for drug delivery to the ovaries has not been fully explored. This is attributed to the fact that they cause cysts in the ovaries and skepticism among patients and physicians. Photo-sensitive devices are an appealing approach for managing disorders affecting the ovaries. Photo-sensitive in situ forming intrauterine implants (IUIs) have several advantages, including simplicity in application, reduced invasiveness, as well as improved site-specific drug release control. Polymeric nanoparticles (PNPs) loaded with a drug may be a suitable choice to provide sustained release, alter the pharmacokinetics, and reduce the dose and dosing frequency. The current manuscript hypothesizes the utility of a PNP-loaded biodegradable photo-responsive intrauterine implantable device as an alternate novel strategy for ameliorating ovarian-related diseases.

Immunotherapy has emerged as a very considerable and potent therapeutic method in which immune inhibitors have gained a lot of attention in the curative field of various cancers. Under certain circumstances, when radiotherapy is accompanied by immunotherapy, the efficacy of the therapeutic procedure increases. Irradiated tumor cells follow a pathway called immunogenic cell death, which targets tumor associated antigens. The application of radiolabeled antibodies under the concept of “radioimmunotherapy” (RIT) makes the synergistic targeted therapeutic effect possible. Since antibodies themselves are cytotoxic, they can kill the cells that not only bind but are within the path length of their radiation emissions. RIT can be categorized as a substantial progress in nuclear medicine. The main concept of RIT includes targeting specified tumor-expressing antibodies. The mentioned purpose is achievable by formulation of radiolabeled antibodies, which could be injected intravenously or directly into the tumor, as well as compartmentally into a body cavity such as the peritoneum, pleura, or intrathecal space. RIT has demonstrated very optimistic therapeutic outcomes in radioresistant solid tumors. Wide ranges of efforts are accomplished in order to improve clinical trial accomplishments. In this review, we intend to summarize the performed studies on RIT and their importance in medicine.

Malignant tumors pose a significant threat to human life and well-being because of their rising occurrence and size. The current treatment methods and diagnostic techniques employed in clinical practice are inadequate for effectively treating tumors. Fluorescence, photothermal effects, radiosensitization, and biocompatibility are only a few instances of the unique photonic and physicochemical properties exhibited. Gold nanoclusters (AuNCs) are nanomaterials that possess modest dimensions, typically measuring approximately 3 nm, and are composed of a limited number of particles. AuNCs have three primary functions in practical applications: serving as imaging agents, drug transporters, and therapeutic agents. This article discusses nanosystems. The text emphasizes the promise of AuNCs for tumor theranostic and combination treatment while also acknowledging any existing limitations. Lastly, it is anticipated that the information presented here will serve as a valuable tool for researchers in this sector, resulting in novel perspectives and, ultimately, a wider adoption of AuNCs in pharmaceuticals. This study focuses on the expansion of diagnostic applications in cancer therapy by utilizing AuNC-based devices, made possible by the use of dynamic or passive tumor targeting techniques. The utilization of AuNCs has been thoroughly investigated for their prospective applicability as light-activated and radiation agents. Furthermore, they have been investigated as nanocarriers for transporting anticancer drugs. The medications can either bind to the closure receptor or be linked to the AuNCs through various techniques, showcasing their extensive potential for therapeutic applications.

Background: Head and Neck Squamous Cell Carcinoma (HNSCC) is a malignant tumor with a high degree of malignancy, invasiveness, and metastasis rate. Radiotherapy, as an important adjuvant therapy for HNSCC, can reduce the postoperative recurrence rate and improve the survival rate. Identifying the genes related to HNSCC radiotherapy resistance (HNSCC-RR) is helpful in the search for potential therapeutic targets. However, identifying radiotherapy resistance-related genes from tens of thousands of genes is a challenging task. While interactions between genes are important for elucidating complex biological processes, the large number of genes makes the computation of gene interactions infeasible. Methods: We propose a gene selection algorithm, RGIE, which is based on ReliefF, Gene Network Inference with Ensemble of Trees (GENIE3) and Feature Elimination. ReliefF was used to select a feature subset that is discriminative for HNSCC-RR, GENIE3 constructed a gene regulatory network based on this subset to analyze the regulatory relationship among genes, and feature elimination was used to remove redundant and noisy features. Results: Nine genes (SPAG1, FIGN, NUBPL, CHMP5, TCF7L2, COQ10B, BSDC1, ZFPM1, GRPEL1) were identified and used to identify HNSCC-RR, which achieved performances of 0.9730, 0.9679, 0.9767, and 0.9885 in terms of accuracy, precision, recall, and AUC, respectively. Finally, qRT-PCR validated the differential expression of the nine signature genes in cell lines (SCC9, SCC9-RR). Conclusion: RGIE is effective in screening genes related to HNSCC-RR. This approach may help guide clinical treatment modalities for patients and develop potential treatments.

Objective: This study aimed to evaluate the therapeutic efficacy and safety of ¹⁷⁷Lutetium-Prostate Specific Membrane Antigen (¹⁷⁷Lu-PSMA-617) radioligand treatment (RLT) in metastatic castration-resistant prostate cancer (mCRPC) patients with aged older than 75 years. Methods: A total of 37 patients with mCRPC aged older than 75 years treated with ¹⁷⁷Lu- PSMA-617 were included in this study. Pre-therapy and post-therapy biochemical, metabolic, and clinical response results and Hb, TLC, platelet, serum creatinine and bilirubin levels were checked to evaluate the therapeutic efficacy and toxicity profile. The Common Terminology Criteria for Adverse Events was used for grading adverse events caused by ¹⁷⁷Lu-PSMA-617 treatment. Results: The mean age of the patients included in the study was 79.8±2.9 (76-92). The number of ¹⁷⁷Lu-PSMA-617 treatment cycles ranged from two to four, and the mean administered radioactivity dose was 5.6±0.8 GBq per cycle. Partial biochemical response (PR) and partial metabolic response (PMR) were observed in 11 (29.7%) and 15 (40.6%) patients after treatment, respectively. Although improvement in ECOG scores was observed in 5 (13.5%) patients after treatment, it was not statistically significant. Grade 2 and 3 Hb toxicity was observed in 10 (27%) and 2 (5.4%) patients, respectively. Grade 2 leukocytopenia in six patients, Grade 1 thrombocytopenia in six patients, and Grade 2 serum creatinine toxicity in five patients were seen after the treatment. On the other hand, no patients developed liver toxicity and grade 3 or 4 leukocytopenia, thrombocytopenia or creatinine toxicity. Conclusion: ¹⁷⁷Lu-PSMA-617 treatment was a safe and effective treatment option for properly selected elderly mCRPC patients.

Background: Despite the escalated production rate, the Iodinated Contrast Media (ICM) shortage continues, and demand outweighs supply. Aim: The aim of this study is to investigate the knowledge and practice of ICM delivery in computed tomography (CT) among radiographers and radiologic technologists worldwide. Methods: An IRB-approved cross-sectional survey used Google Forms for data collection. It involved 94 CT radiographers from 27 countries and was divided into five sections. The first section gathered demographic information, followed by sections on experience, self-assessment of ICM reactions, and delivery technique. The third section explored ICM knowledge and its relation to CT parameters. The fourth and fifth sections focus on practices during pulmonary angiography CT and renal CT scans. Data analysis involved descriptive statistics, the Chi- Square test, and ANOVA. Results: Knowledge was assessed with seven questions, and a score of at least 3.5 was needed for categorization. The median score was two, indicating low knowledge. Specifically, 64.9% of the participants scored lower than the two scores. Years of experience are strongly correlated with the level of knowledge, with 51.6% of radiographers having more than 10 years of experience demonstrating adequate knowledge. 41.7% of respondents demonstrated adequate knowledge when their duty was focused on CT. Furthermore, wide practice variability exists in all CT pulmonary angiography protocols among radiographers with adequate and inadequate knowledge. Conclusion: Inexperienced individuals showed knowledge gaps, leading to varied practices and highlighting the need for educational programs. The study underscores establishing standardized Protocols and Practice Guidelines (PPGs) for contrast media administration in Radiology Departments. Additionally, it emphasizes the importance of regular training programs, and international knowledge sharing. The potential for self-selection bias in the online survey sample is highlighted.

Background: Radiotherapy plays a vital role in the management of high-grade gliomas. However, the radio resistance of glioma cells limits the effect of radiation and drives recurrence inside the irradiated tumor volume leading to poor outcomes for patients. Methods: High-grade glioma cell radioresistance significantly contributes to radiotherapy failure, highlighting the importance of identifying predictive biomarkers for radioresistance. An increasing body of evidence complies with the Yes Associated Protein 1 (Yap-1) and heat shock protein 90 (Hsp90) as biomarkers for radioresistance in glioma cells. A number of studies suggest the potential of radioresistance-associated factors as biomarkers and/ or novel therapeutic targets in glioma cells. Thus, it is essential for glioblastoma patients to identify robust druggable targets involved in radioresistance, optimizing irradiation protocol, and understanding their underlying molecular mechanisms. Results: Therefore, in the present study, we hypothesized that hypofractionated Gamma Knife radiation therapy (HF-GKRT) could target Yap-1 and Hsp90 and downregulate the mechanism of radioresistance in high-grade glioma cells. Conclusion: For this purpose, expression levels of radioresistance markers Yap-1 and Hsp90 were evaluated after treatment with HF-GKRT, and this was compared with single fraction Gamma Knife radiation therapy (SF-GKRT) in U87MG primary human glioblastoma cell line model. This would help design a novel radiation therapy regimen for glioblastoma patients by reducing the risk of radioresistance.

Purpose: This study aimed to evaluate the performance of 18F-MD-PSMA PET/CT in patients previously treated for prostate cancer by either surgery or therapy, but later relapsed biochemically. Methods: This retrospective study enrolled 213 patients in sequence previously treated for prostate cancer by either surgery or therapy, but later PSA relapsed. A total of 191 of these 213 patients were included in this analysis. All patients were biochemically relapsed after radical prostatectomy or therapy, had 18F-MD-PSMA PET/CT scan within 1 week, and were off hormonal therapy at the time of the scans. The new tracer was compared directly with 11C-choline in sensitivity. Results: In 3 patients, a side-by-side comparison between 18F-MD-PSMA and 11C-choline was performed, and it was found that the former was about 3 times more sensitive than the latter. The analysis of PET imaging using 18F-MD-PSMA in 191 relapsed patients showed that less than 10% of patients showed the disease limited in the prostate. Among the remote lesions, the number in decreasing order was bone, followed by lymph nodes and other organs. The maximal SUV in lesions in each patient followed an exponential decay, with SUV inclined to the lower end. The Gleason score measured at the diagnosis showed no correlation with the average number of lesions in each patient, the average maximal SUV values among this cohort of patients, and the PSA values measured at the time of PET imaging. The number of lesions observed in each patient has no correlation with the PSA value measured at the time of PET imaging. When PSA value was measured as an independent biomarker at the time of PET imaging, the positivity of PET imaging using 18F-MD-PSMA increased along with an increase in PSA value, but with exceptions where PSMA expression was low or negative. From the PET imaging of this radioligand, the majority of patients showed oligo-metastasis, favoring using local therapy to manage the disease. Conclusion: An 18F-MD-PSMA as a radioligand was found to be superior to 11C-choline in the setting of patients with biochemical relapse after previous treatment. Its PET imaging results matched those of established PSMA radioligands, but its chemical structure was found to have added features to conjugate with other functional molecules, such as those with therapeutic properties. This radioligand lays the foundation for our further work.