In our previous study, monogalactosyl diacylglycerol (MGDG) purified from spinach was found to have cytotoxic effects in human cancer cell lines. This study further assessed whether MGDG can enhance the cytotoxic effects of radiation in human pancreatic cancer cells in vitro and in vivo. Glycoglycerolipids from spinach including MGDG were extracted from dried spinach. The cytotoxicity of MGDG were evaluated by the MTT assay using four human pancreatic cancer cell lines (MIAPaCa-2, AsPC-1, BxPC-3 and PANC-1) and normal human dermal fibroblasts (NHDFs). The effects of radiation and MGDG alone or in combination in MIAPaCa-2 cells was analyzed with the colony forming and apoptosis assays, western blotting and cell cycle and DNA damage analyses (γ-H2AX foci staining and comet assay). The inhibitory effects on tumor growth were assessed in a mouse xenograft tumor model. MGDG showed dose- and time-dependent cytotoxicity, with half-maximal inhibitory concentrations (IC50) in PANC-1, BxPC-3, MIAPaCa-2 and AsPC-1 cells at 72 h of 25.6 ± 2.5, 26.9 ± 1.3, 18.5 ± 1.7, and 22.7 ± 1.9 μM, respectively. The colony forming assay revealed fewer MIAPaCa-2, BxPC-3 and AsPC-1 cell colonies upon treatment with both MGDG and radiation as compared to irradiation alone (P < 0.05). The combination of MGDG and radiation induced a higher proportion of apoptosis in MIAPaCa-2 cells; this effect was associated with increased mitochondrial release of cytochrome c and activation of cleaved poly (ADP-ribose) polymerase and caspase-3. DNA damage was detected and DNA repair mechanisms were more frequently impaired in cells receiving the combination treatment as compared to either one alone. Tumor growth was inhibited to a greater degree in mice treated by intratumoral injection of MGDG combined with irradiation as compared to either one alone (P < 0.05). This is the first report demonstrating that MGDG enhances the cytotoxicity of radiation to induce apoptosis of cancer cells in vitro and in vivo. Our findings indicate that this therapeutic combination can be an effective strategy for the treatment of pancreatic cancer.

Aim: To investigate tumour motion tracking uncertainties in the CyberKnife Synchrony system with single fiducial marker in liver tumours. Background: In the fiducial-based CyberKnife real-time tumour motion tracking system, multiple fiducial markers are generally used to enable translation and rotation corrections during tracking. However, sometimes a single fiducial marker is employed when rotation corrections are not estimated during treatment. Materials and methods: Data were analysed for 32 patients with liver tumours where one fiducial marker was implanted. Four-dimensional computed tomography (CT) scans were performed to determine the internal target volume (ITV). Before the first treatment fraction, the CT scans were repeated and the marker migration was determined. Log files generated by the Synchrony system were obtained after each treatment and the correlation model errors were calculated. Intra-fractional spine rotations were examined on the spine alignment images before and after each treatment. Results: The mean (standard deviation) ITV margin was 4.1 (2.3) mm, which correlated weakly with the distance between the fiducial marker and the tumour. The mean migration distance of the marker was 1.5 (0.7) mm. The overall mean correlation model error was 1.03 (0.37) mm in the radial direction. The overall mean spine rotations were 0.27 degrees (0.31), 0.25 degrees (0.22), and 0.23 degrees (0.26) for roll, pitch, and yaw, respectively. The treatment time was moderately associated with the correlation model errors and weakly related to spine rotation in the roll and yaw planes. Conclusions: More caution and an additional safety margins are required when tracking a single fiducial marker. (C) 2019 Greater Poland Cancer Centre. Published by Elsevier B.V. All rights reserved.

Gastrointestinal toxicity is frequently observed secondary to accidental or therapeutic radiation exposure. However, the variation in the intestinal metabolites after abdominal radiation exposure remains ambiguous. In the present study, C57BL/6 mice were exposed to 0, 2, and 20 Gy irradiation dose. The Head and chest of each mouse were covered with a lead shield before x-ray irradiation. 24 h post-irradiation treatment, intestinal tissue of each mouse was excised and prepared for metabolites measurement using gas chromatography-mass spectrometry (GC-MS). Our comprehensive analysis of metabolites in the intestinal tissues detected 44 metabolites after irradiation, including amino acids, carbohydrates, organic acids, and sugars. Amino acid levels in the intestinal tissue gradually rose, dependent on the radiation dose, perhaps as an indication of oxidative stress. Our findings raise the possibility that amino acid metabolism may be a potential target for the development of treatments to alleviate or mitigate the harmful effects of oxidative stress-related gastrointestinal toxicity due to radiation exposure.

Background: Proanthocyanidins (PACs) from black soybean seed coat have antioxidant and anti-tumorigenic properties. We investigated the anti-tumor properties and mechanisms of action of PACs on colorectal cancer (CRC). Methods: We fed the APC^min/+ mice, which are highly susceptible to spontaneous intestinal adenoma formation, diets supplemented with or without PACs for 7 weeks and assessed adverse effects, the number and size of intestinal polyps, and the expression of pro- and anti-proliferative proteins in the intestine. The mouse gut microbiome composition was analyzed, and the concentrations of gut short-chain fatty acids (SCFAs) were quantified. We also compared CRC incidence in Tamba in Japan, where black soybean is consumed frequently, with that in the rest of Japan. Results: The number and size of intestinal polyps notably decreased in the PAC-fed mice. Compared with control mice, the PAC-fed mice showed lower expression of proliferation markers proliferating cell nuclear antigen and β catenin and a higher expression of the anti-inflammatory protein oligomeric mucus gel-forming. PAC supplementation increased the prevalence and concentrations of beneficial gut microbes and SCFAs, respectively. Conclusions: Diet supplemented with black soybean-derived PACs could prevent CRC development in mice through gut microbiome remodeling. Regions consuming black soybeans have low CRC incidence. Notably, the incidence of CRC, breast cancer, and liver cancer was significantly lower in Tamba than in the rest of Hyogo Prefecture or Japan. Future studies should delineate the mechanisms underlying the CRC-protective effects of PACs. Nevertheless, our results demonstrate the potential of including PACs in dietary recommendations for cancer prevention.

This chapter discusses the clinical application and implementation of wedge techniques in radiation therapy. Coverage of the target region with a curative dose is critical for treating several cancer types; to that end, wedge filters are commonly used to improve dose uniformity to the target volume. Initially, wedges designed for this purpose were physical and were made of high-density materials such as lead or steel. Subsequently, nonphysical wedges were introduced; these improved the dose uniformity using computer systems in lieu of physical materials. As wedge systems evolve, however, they each continue to have their advantages and disadvantages. When using physical wedges, it is difficult to control the generation of secondary radiation resulting from the collision of the radiation beam with the wedge body; conversely, nonphysical wedges do not create any secondary radiation because there is no physical interference with the beam. On the other hand, nonphysical wedges are less suitable for treating moving tumors, such as those in the lung, and physical wedges have better dose coverage to the target volume than nonphysical wedges. This chapter aims to guide decision-making regarding the choice of wedge types in various clinical situations.

Purpose/Objectives: The mechanism of intercellular communication after radiation exposure in cancer cells remains fully undetermined. Exosomes are lipid bilayer-constituted, membrane-enclosed small vesicles that are recognized as mediators transporting a variety of intracellular components including miRNA. Here we identified the novel role of exosomes released from irradiated cells to neighboring cancer cells. Materials/Methods: Human pancreatic cancer cell line MIAPaCa-2 was used in this study. Purified exosome product (PEP) was obtained from cultured media by ultra-centrifugation. PEP was morphologically confirmed by transmission electron microscopy (TEM), and analyzed by NanoSight. Exosome-specific surface markers CD9 and CD63 were evaluated by western blotting. Endocytosis of irradiated exosomes was confirmed by fluorescent microscopy by using the PKH26 dye. Cell survival after irradiation was evaluated by a colony-forming assay. Intracellular reactive oxygen species (ROS) levels were determined using the oxidation-sensitive fluorescent probe dye C-H 2 DCF, and DNA damage was evaluated by detecting phosphorylated histone 2AX (γ-H2AX) foci by immunocytochemistry. MiRNAs were isolated from the exosomes after 5 Gy or 8 Gy of irradiation and comprehensive miRNA expression analysis was performed by miRNA microarray analyses. Expressions of Cu/Zn superoxide dismutase enzyme (SOD1) or Mn superoxide dismutase enzyme (SOD2), catalase, and glutathione peroxidase were studied to determine whether the exosomes received by the neighboring cells may have influence to them and lead to production of ROS or not. Results: Exosome characteristics were confirmed by multiple methods. The uptake of irradiated exosomes was significantly higher than that of nonirradiated exosomes. Notably, nonirradiated neighboring cells with irradiated exosomes induced higher intracellular levels of ROS, and a higher frequency of DNA damage. These neighboring cells also showed greater sensitivity to radiation. Seven upregulated and 5 downregulated miRNAs were identified that correlated with the miRNA microarray analyses results obtained after 5 Gy and 8 Gy radiation. Among them, miR-6823-5p was identified as a possible candidate for SOD1 inhibition, leading to intracellular ROS production and DNA damage. Conclusions : This is the first study to determine that irradiated exosomes can enhance the radiation effect via ROS production in cancer cells. This novel finding may lead to the understanding of the bystander effect of neighboring cancer cells.