Radiobiology

INTRODUCTION: Targeted α-particle therapy agents have shown promising responses in patients who have developed resistance to β- -particle emitting radionuclides, albeit off-target toxicity remains a concern. Astatine-211 emits only one α-particle per decay and may alleviate the toxicity from α-emitting daughter radionuclides. Previously, we developed the low-molecular-weight PSMA-targeted agent [211 At]L3-Lu that showed suitable therapeutic efficacy and was well tolerated in mice...

OBJECTIVE: Traditional cell-based radiobiological methods are inadequate for assessing the toxicity of ionizing radiation exposure in relation to the microstructure of the extracellular matrix. Organotypic tissue slices preserve the spatial organization observed in vivo, making the tissue easily accessible for visualization and staining. This study aims to explore the use of fluorescence microscopy of physiologically compatible 3D tissue cultures to assess the effects of ionizing radiation...

Chemokine receptors are important components of cellular signaling and play a critical role in directing leukocytes during inflammatory reactions. Their importance extends to numerous pathological processes, including tumor differentiation, angiogenesis, metastasis, and associations with multiple inflammatory disorders. The necessity to monitor the in vivo interactions of cellular chemokine receptors has been driven the recent development of novel positron emission tomography (PET) imaging agents. This imaging modality provides non-invasive localization and quantitation of these receptors that cannot be provided through blood or tissue-based assays...

BACKGROUND: This study aimed to evaluate the clinical efficacy of coaxial percutaneous Iodine-125 (125 I) seed implantation in combination with arterial infusion chemotherapy for the treatment of advanced pancreatic cancer (PC) through a randomized controlled trial. METHODS: A total of 101 patients with advanced PC were randomized into two groups: control group treated with systemic intravenous chemotherapy and experimental group that received 125 I seed implantation in combination with arterial infusion chemotherapy...

PURPOSE: The dicentric chromosome assay (DCA), often referred to as the 'gold standard' in radiation dose estimation, exhibits significant challenges as a consequence of its labor-intensive nature and dependency on expert knowledge. Existing automated technologies face limitations in accurately identifying dicentric chromosomes (DCs), resulting in decreased precision for radiation dose estimation. Furthermore, in the process of identifying DCs through automatic or semi-automatic methods, the resulting distribution could demonstrate under-dispersion or over-dispersion, which results in significant deviations from the Poisson distribution...

INTRODUCTION: Osteoradionecrosis of the mandible (ORN) remains a significant complication in the intensity modulated radiotherapy (IMRT) era. Dental dose cannot be predicted from heterogeneous IMRT dose distributions; mandibular dose metrics cannot guide dentist avulsion decisions in high risk ORN situations. Using a mapping tool to report dental root dose, avulsions and ORN sites, we reexamined ORN risk factors in a case-control study. METHODS: From 2008 to 2019, 897 consecutive patients with oral cavity/oropharynx (OC/OR) or unknown primary cancer (CUP) and undergoing IMRT were analyzed to identify ORN cases...

PURPOSE: Creatine (Cr) and l-arginine are naturally occurring guanidino compounds, commonly used as ergogenic dietary supplements. Creatine and l-arginine exhibit also a number of non-energy-related features, such as antioxidant, anti-apoptotic, and anti-inflammatory properties, which contribute to their protective action against oxidative stress (OS). In this regard, there are a number of studies emphasizing the protective effect of Cr against OS, which develops in the process of aging, increased physical loads as part of athletes' workouts, as well as a number of neurological diseases and toxic effects associated with xenobiotics and UV irradiation...

PURPOSE: Gamma rays are the most widely exploited physical mutagen in plant mutation breeding. They are known to be involved in the development of more than 60% of global cowpea ( Vigna unguiculata (L.) Walp.) mutant varieties. Nevertheless, the nature and type of genome-wide mutations induced by gamma rays have not been studied in cowpea and therefore, the present investigation was undertaken. MATERIALS AND METHODS: Genomic DNAs from three stable gamma rays-induced mutants (large seed size, small seed size and disease resistant mutant) of cowpea cultivar 'CPD103' in M6 generation along with its progenitor were used for Illumina-based whole-genome resequencing...

Given the radiobiological and physical properties of the proton, proton beam therapy has the potential to be advantageous for many patients compared with conventional radiotherapy by limiting toxicity and improving patient outcomes in specific breast cancer scenarios.

BACKGROUND: Stereotactic ablative body radiotherapy (SABR) is a novel option to treat primary renal cell carcinoma (RCC). However, a high radiation dose may be received by the treated kidney, which may affect its function post-treatment. This study investigates the dose-effect relationship of kidney SABR with posttreatment renal function. METHODS: This was a prespecified secondary endpoint of the multicenter FASTRACK II clinical trial (NCT02613819). Patients received either 26 Gy in a single fraction (SF) for tumors with a maximal diameter of 4 cm or less, or 42 Gy in three fractions (multi-fraction (MF)) for larger tumors...

BACKGROUND: Tumor-infiltrating lymphocytes (TILs) have prognostic significance in several cancers, including breast. Despite interest in combining radiotherapy with immunotherapy, little is known about the effect of radiotherapy itself on the tumor-immune microenvironment, including TILs. Here, we interrogated longitudinal dynamics of tumor-infiltrating and systemic lymphocytes in patient samples taken before, during, and after neoadjuvant radiotherapy (NART), from XXX and XXX breast clinical trials...

The first half of 2022 saw the publication of several major research advances in image-based models and artificial intelligence applications to optimize treatment strategies for high-grade gliomas, the deadliest brain tumors. We review them and discuss the barriers that delay their entry into clinical practice; particularly, the small sample size and the heterogeneity of the study designs and methodologies used. We will also write about the poor and late palliation that patients suffering from high-grade glioma can count on at the end of life, as well as the current legislative instruments, with particular reference to Italy...

Radium-223 (223 Ra) and Lutetium-177-labelled-PSMA-617 (177 Lu-PSMA) are currently the only radiopharmaceutical treatments to prolong survival for patients with metastatic-castration-resistant prostate cancer (mCRPC); however, mCRPC remains an aggressive disease. Recent clinical evidence suggests patients with mutations in DNA repair genes associated with homologous recombination have a greater clinical benefit from 223 Ra. In this study, we aimed to determine the utility of combining DNA damage response (DDR) inhibitors to increase the therapeutic efficacy of X-rays, or 223 Ra...

BACKGROUND: Pancreatic cancer is one of the most aggressive and lethal cancers. New treatment strategies are highly warranted. Particle radiotherapy could offer a way to overcome the radioresistant nature of pancreatic cancer because of its biological and physical characteristics. Within particles, helium ions represent an attractive therapy option to achieve the highest possible conformity while at the same time protecting the surrounding normal tissue. The aim of this study was to evaluate the cytotoxic efficacy of helium ion irradiation in pancreatic cancer in vitro...

Radiotherapy developed empirically through experience balancing tumour control and normal tissue toxicities. Early simple mathematical models formalized this practical knowledge and enabled effective cancer treatment to date. Remarkable advances in technology, computing, and experimental biology now create opportunities to incorporate this knowledge into enhanced computational models. The ESTRO DREAM (Dose Response, Experiment, Analysis, Modelling) workshop brought together experts across disciplines to pursue the vision of personalized radiotherapy for optimal outcomes through advanced modelling...

No abstract text is available yet for this article.

PURPOSE: Present study deals with the role of gamma irradiation in modulating arsenic bioremediation of Pseudomonas sp. AK1 and AK9 strains. MATERIALS AND METHODS: The bacterial strains AK1 and AK9 of Pseudomonas sp. were irradiated at different doses (5 Gy, 10 Gy, 15 Gy and 20 Gy) of gamma irradiation. The effect of γ-irradiation on the growth and arsenic modulating ability of AK1 and AK9 strains was determined in the presence and absence of arsenic along with non-irradiated strains...

FLASH-radiotherapy delivers a radiation beam a thousand times faster compared to conventional radiotherapy, reducing radiation damage in healthy tissues with an equivalent tumor response. Although not completely understood, this radiobiological phenomenon has been proved in several animal models with a spectrum of all kinds of particles currently used in contemporary radiotherapy, especially electrons. However, all the research teams have performed FLASH preclinical studies using industrial linear accelerator or LINAC commonly employed in conventional radiotherapy and modified for the delivery of ultra-high-dose-rate (UHDRs)...

PURPOSE: The effect of chronic low dose-rate radiation exposure on cancers was investigated by analyzing the data of mice experiments conducted at the Institute for Environmental Sciences (IES). This analysis focuses on the differences between malignant lymphomas and solid cancers. MATERIALS AND METHODS: The analysis is conducted based on the mathematical model introduced in our previous work. The model is expanded to analyze malignant lymphomas and solid cancers separately...

Spatially fractionated radiation therapy (SFRT) is a therapeutic approach with the potential to disrupt the classical paradigms of conventional radiation therapy. The high spatial dose modulation in SFRT activates distinct radiobiological mechanisms which lead to a remarkable increase in normal tissue tolerances. Several decades of clinical use and numerous preclinical experiments suggest that SFRT has the potential to increase the therapeutic index, especially in bulky and radioresistant tumors. To unleash the full potential of SFRT a deeper understanding of the underlying biology and its relationship with the complex dosimetry of SFRT is needed...