Pancreatic cancer has the lowest 5 year survival rate among all cancers. Several extracellular factors are involved in the development and metastasis of pancreatic cancer to distant organs. Exosomes are lipid-bilayer, membrane-enclosed nanoparticles that are recognised as important mediators of cell-to-cell communications. However, the role of exosomes released from pancreatic cancer cells in tumour micro-environment remains unknown. Here, we show that exosomes released from pancreatic cancer PK-45H cells activate various gene expressions in human umbilical vein endothelial cells (HUVECs) byin vitroanalyses. In addition, these exosomes released from PK-45H cells promote phosphorylation of Akt and ERK1/2 signalling pathway molecules and tube formation via dynamin-dependent endocytosis in HUVECs. Our findings suggested that exosomes released from pancreatic cancer cells may act as a novel angiogenesis promoter.

A car-borne survey for dose rate in air was carried out in March and April 2011 along an expressway passing northwest of the Fukushima Dai-ichi Nuclear Power Station which released radionuclides starting after the Great East Japan Earthquake on March 11, 2011, and in an area closer to the Fukushima NPS which is known to have been strongly affected. Dose rates along the expressway, i.e. relatively far from the power station were higher after than before March 11, in some places by several orders of magnitude, implying that there were some additional releases from Fukushima NPS. The maximum dose rate in air within the high level contamination area was 36 μGy h⁻¹, and the estimated maximum cumulative external dose for evacuees who came from Namie Town to evacuation sites (e.g. Fukushima, Koriyama and Nihonmatsu Cities) was 68 mSv. The evacuation is justified from the viewpoint of radiation protection.

Radionuclide concentrations in environmental samples such as surface soils, plants and water were evaluated by high purity germanium detector measurements. The contribution rate of short half-life radionuclides such as ¹³²I to the exposure dose to residents was discussed from the measured values. The highest values of the ¹³¹I/¹³⁷Cs activity ratio ranged from 49 to 70 in the environmental samples collected at Iwaki City which is located to the south of the F1-NPS. On the other hand, the ¹³²I/¹³¹I activity ratio in the same environmental samples had the lowest values, ranging from 0.01 to 0.02. By assuming that the ¹³²I/¹³¹I activity ratio in the atmosphere was equal to the ratio in the environmental samples, the percent contribution to the thyroid equivalent dose by ¹³²I was estimated to be less than 2%. Moreover, the contribution to the thyroid exposure by ¹³²I might be negligible if ¹³²I contamination was restricted to Iwaki City.

NFE2-related factor 2 (Nrf2), which belongs to the cap “n” collar family of basic region leucine zipper transcription factors, is a key protein in the coordinated transcriptional induction of expression of various antioxidant genes. The purpose of this study was to analyze the expression of Nrf2 target genes, such as heme oxygenase 1 (HO-1), ferritin heavy polypeptide 1 (FTH1), NAD(P)H dehydrogenase, quinone 1 (NQO1), glutamate-cysteine ligase catalytic subunit, glutamate-cysteine ligase modifier subunit, glutathione reductase (GSR) and thioredoxin reductase 1 (TXNRD1), after X irradiation of CD34+ cells that were prepared from human placental/umbilical cord blood hematopoietic stem cells (HSCs). We evaluated the relationship between radiosensitivity and expression of Nrf2 target genes in HSCs. The number of colony-forming cells derived from 2-Gy-irradiated HSCs decreased to approximately 20% of the nonirradiated control. At the same time, the mRNA expression of HO-1, FTH1, NQO1, GSR and TXNRD1 w...

Spandidos Publications is a scientific publisher with a long-standing international reputation for excellent standards and high quality science publications

Exposure to high-doses of ionizing radiation (IR) leads to development of a strong acute radiation syndrome (ARS) in mammals. ARS manifests after a latency period and it is important to develop fast prognostic biomarkers for its early detection and assessment. Analysis of chromosomal aberrations in peripheral blood lymphocytes is the gold standard of biological dosimetry, but it fails after high doses of IR. Therefore, it is important to establish novel biomarkers of exposure that are fast and reliable also in the high dose range. Here, we investigated the applicability of miRNA levels in mouse serum. We found significantly increased levels of miR-375-3p following whole body exposure to 7 Gy of X-rays. In addition, we analyzed their levels in various organs of control mice and found them to be especially abundant in the pancreas and the intestine. Following a dose of 7 Gy, extensive cell death occurred in these tissues and this correlated negatively with the levels of miR-375-3p in the organs. We conclude that high expressing tissues of miR-375-3p may secrete this miRNA in serum following exposure to 7 Gy. Therefore, elevated miR-375-3p in serum may be a predictor of tissue damage induced by exposure to a high radiation dose.