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Hypofractionated stereotactic body radiation therapy (SBRT) for prostate cancer (PCa) can be delivered with the robot-assisted CyberKnife (CK) system or on a linear accelerator using dynamic intensity-modulated radiotherapy (IMRT) or volumetric arc radiotherapy (VMAT). This retrospective study was performed to determine whether CK offers better dose distribution than IMRT and/or VMAT.

Patients with left breast cancer who undergo radiotherapy have a non-negligible risk of developing radiation-induced cardiovascular disease (CVD). Cardioprotection can be achieved through better treatment planning protocols and through respiratory gating techniques, including deep inspiration breath hold (DIBH). Several dosimetric studies have shown that DIBH reduces the cardiac dose, but clinical data confirming this effect is limited. The aim of the study was to compare the mean heart dose (MHD) in patients with left breast cancer who underwent radiotherapy at our institution as we transitioned from non-gated free-breathing (FB) radiotherapy to gated radiotherapy (FB-GRT), and finally to DIBH.

Although the effects of high dose radiation on human cells and tissues are relatively well defined, there is no consensus regarding the effects of low and very low radiation doses on the organism. Ionizing radiation has been shown to induce gene mutations and chromosome aberrations which are known to be involved in the process of carcinogenesis. The induction of secondary cancers is a challenging long-term side effect in oncologic patients treated with radiation. Medical sources of radiation like intensity modulated radiotherapy used in cancer treatment and computed tomography used in diagnostics, deliver very low doses of radiation to large volumes of healthy tissue, which might contribute to increased cancer rates in long surviving patients and in the general population. Research shows that because of the phenomena characteristic for low dose radiation the risk of cancer induction from exposure of healthy tissues to low dose radiation can be greater than the risk calculated from linear no-threshold model. Epidemiological data collected from radiation workers and atomic bomb survivors confirms that exposure to low dose radiation can contribute to increased cancer risk and also that the risk might correlate with the age at exposure.

Introduction. The rapid development of new radiotherapy technologies, such as intensity modulated radiotherapy (IMRT) or tomotherapy, has resulted in the capacity to deliver a more homogenous dose in the target. However, the higher doses associated with these techniques are a reason for concern because they may increase the dose outside the target. In the present study, we compared 3DCRT, IMRT and tomotherapy to assess the doses to organs at risk (OARs) resulting from photon beam irradiation and scattered neutrons.

Malignant tumors are a leading cause of death worldwide, second only to cardiovascular disease. They occur in every population and have a high risk of mortality. The etiopathogenesis of malignant tumors is diverse and there are still many unknowns, leading to huge diagnostic and therapeutic challenges. Therefore, the search for ideal diagnostic and therapeutic agents is ongoing. One of the promising factors affecting cancer is the nucleus accumbens associated protein 1 (NACC1). It is a transcriptional coregulator. Moreover, it plays a multifaceted role in promoting tumorigenesis. NACC1 expression analyses were performed using The Cancer Genome Atlas (TCGA) data accessed from the University of Alabama at Birmingham Cancer (UALCAN) database, and the expression data were interconnected with clinicopathological parameters. All statistical analyses were conducted using GraphPad Prism and Statistica. The results revealed that NACC1 was expressed in almost all of the analyzed cancers, and its expression level correlates with different clinicopathological parameters. This study demonstrates that NACC1 is potentially involved in the pathogenesis, invasion, and immune response associated with many cancers. However, NACC1 is not a suitable candidate as a diagnostic biomarker as it is not specific for any type of malignancy and there are discrepancies in its expression in relation to many clinicopathological parameters. The implementation of NACC1 as a therapeutic target may improve the effectiveness of cancer treatments. [ABSTRACT FROM AUTHOR]

Simple Summary: Patient-specific factors must be thoroughly analyzed to minimize the side effects of applied treatments. This study examined the radiobiological response of established and patient-derived malignant cell lines, cancer-associated fibroblasts, and skin fibroblasts to proton irradiation (IRR). Using clonogenic assay, γH2AX, and p53 staining, it was found that breast cancer cell lines of different subtypes had similar responses. However, cancer-associated fibroblasts from TNBC tumors were more resistant than those from luminal A tumors. Skin fibroblasts responded uniformly across all doses. The responses of patient-derived cell lines suggested that each patient may have a distinct radiotherapy result due to specific tumor microenvironmental characteristics. Research on different types of ionizing radiation's effects has been ongoing for years, revealing its efficacy in damaging cancer cells. Solid tumors comprise diverse cell types, each being able to respond differently to radiation. This study evaluated the radiobiological response of established (MDA-MB-231 (Triple negative breast cancer, TNBC), MCF-7 (Luminal A)) and patient-derived malignant cell lines, cancer-associated fibroblasts, and skin fibroblasts following proton IRR. All cell line types were irradiated with the proton dose of 2, 4, and 6 Gy. The radiobiological response was assessed using clonogenic assay, γH2AX, and p53 staining. It was noticeable that breast cancer lines of different molecular subtypes displayed no significant variations in their response to proton IRR. In terms of cancer-associated fibroblasts extracted from the tumor tissue, the line derived from a TNBC subtype tumor demonstrated higher resistance to ionizing radiation compared to lines isolated from luminal A tumors. Fibroblasts extracted from patients' skin responded identically to all doses of proton radiation. This study emphasizes that tumor response is not exclusively determined by the elimination of breast cancer cells, but also takes into account tumor microenvironmental variables and skin reactions. [ABSTRACT FROM AUTHOR]

Background: The biological effects and clinical consequences of out-of-field radiation in peripheral organs can be difficult to determine, especially for low doses (0.1 Gy-1 Gy). In recent years, Monte Carlo (MC) methods have been proposed to more accurately predict nontarget doses. The aim of the present study was to assess the feasibility of using Monte Carlo methods to predict the biological response of tissues and critical organs to low dose radiation (0.1 to 1 Gy) based on results published in the literature. Materials and methods: Literature review, including studies published by our group. Results and Conclusions: It has long been assumed that radiation doses to peripheral organs located far from the target volume are too low to have any clinical impact. In recent years, however, concerns about the risk of treatment-induced secondary cancers, even in peripheral organs, have continued to grow in line with increasing life expectancy. At present, it is difficult in routine calculations to accurately determine radiation doses to the whole body and peripheral organs. Moreover, the potential clinical impact of these doses remains uncertain and the biological response to low dose radiation depends on the organ. In this context, MC methods can predict biological response in those organs. Monte Carlo methods have become a powerful tool to better predict the consequences of interactions between ionising radiation and biological matter. MC modelling can also help to characterise microscopic system dynamics and to provide a better understanding of processes occurring at the cellular, molecular, and nanoscales. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) is one of the most frequently diagnosed cancers in the world. Although the incidence is decreasing in developed countries, the treatment results are still unsatisfactory. The standard treatment for locally advanced gastric cancer (LAGC) is gastrectomy with perioperative chemotherapy. The association of selected microRNAs (miRNAs) with chemoresistance was assessed using archival material of patients with LAGC. Histological material was obtained from each patient via a biopsy performed during gastroscopy and then after surgery, which was preceded by four cycles of neoadjuvant chemotherapy (NAC) according to the FLOT or FLO regimen. The expression of selected miRNAs in the tissue material was assessed, including miRNA-21-3p, miRNA-21-5p, miRNA-106a-5p, miRNA-122-3p, miRNA-122-5p, miRNA-143-3p, miRNA-143-5p, miRNA-203a-3p, miRNA-203-5p, miRNA-551b-3p, miRNA-551b-5p, and miRNA-574-3p. miRNA expression was assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The response to NAC was assessed using computed tomography of the abdomen and chest and histopathology after gastrectomy. The statistical analyses were performed using GraphPad Prism 9. The significance limit was set at p < 0.05. We showed that the expression of miR-143-3p, miR-143-5p, and miR-574-3p before surgery, and miR-143-5p and miR-574-3p after surgery, decreased in patients with GC. The expression of miR-143-3p, miR-143-5p, miR-203a-3p, and miR-551b-5p decreased in several patients who responded to NAC. The miRNA most commonly expressed in these cases was miRNA-551b-5p. Moreover, it showed expression in a patient whose response to chemotherapy was inconsistent between the histopathological results and computed tomography. The expression of miR-143-3p, miR-143-5p, miR-203a-3p, and miR-551b-5p in formalin-fixed paraffin-embedded tissue (FFPET) samples can help differentiate between the responders and non-responders to NAC in LAGC. miR-143-3p, miR-143-5p, and miR-574-3p expression may be used as a potential diagnostic tool in GC patients. The presence of miR-551b-5p may support the correct assessment of a response to NAC in GC via CT. [ABSTRACT FROM AUTHOR]

Background: Proton therapy has garnered attention as an advanced radiation treatment modality for breast cancer due to its ability to deliver highly precise doses to the target area while minimizing exposure to surrounding healthy tissues. The aim was to detect potential variations in radiobiological response along different parts of the proton depth-dose curve. Materials and methods: MDA-MB-231 cells were specifically irradiated before, within, and beyond the Bragg peak with a 5 Gy dose, with photons used as a reference. The radiobiological response was evaluated using clonogenic assays, relative γH2AX levels, and quantitative polymerase chain reaction (qPCR) analysis of DNA damage response genes. Results: A trend of increasing magnitude in radiobiological response was observed with increasing depth of cell irradiation, accompanied by a decrease in survival fraction. Furthermore, differences were noted, particularly in γH2AX levels along the Bragg peak, with higher values of DNA double-strand breaks (DNA DSB) observed at the end of the depth-dose curve. Conclusions: These findings suggest that despite administering a consistent proton dose to the target area, there can be a range of different biological reactions, which might have significant indications for clinical procedures. [ABSTRACT FROM AUTHOR]