Correction: Hypoxia/reoxygenation-experienced cancer cell migration and metastasis are regulated by Rap1- and Rac1-GTPase activation the expression of thymosin beta-4.

[This corrects the article DOI: 10.18632/oncotarget.3218.

Low-Dose Ionizing γ-Radiation Promotes Proliferation of Human Mesenchymal Stem Cells and Maintains Their Stem Cell Characteristics.

Mesenchymal stem cells (MSCs), which are multipotent and have self-renewal ability, support the regeneration of damaged normal tissue. A number of external stimuli promote migration of MSCs into peripheral blood and support their participation in wound healing. In an attempt to harness the potential beneficial effects of such external stimuli, we exposed human MSCs (hMSCs) to one such stimulus-low-dose ionizing radiation (LDIR)-and examined their biological properties.

In vivo monitoring of CD44+ cancer stem-like cells by γ-irradiation in breast cancer.

There is increasing evidence that cancer contains cancer stem cells (CSCs) that are capable of regenerating a tumor following chemotherapy or radiotherapy. CD44 and CD133 are used to identify CSCs. This study investigated non-invasive in vivo monitoring of CD44-positive cancer stem-like cells in breast cancer by γ-irradiation using molecular image by fusing the firefly luciferase (fLuc) gene with the CD44 promoter.

ASSESSMENT OF DIAGNOSTIC MULTILEAF COLLIMATOR FOR CEPHALOMETRIC EXPOSURE REDUCTION USING OPTICALLY STIMULATED LUMINESCENT DOSEMETERS.

A diagnostic multileaf collimator (MLC) was developed for diagnostic radiography dose reduction. Optically stimulated luminescent dosemeters (OSLDs) were used to evaluate the efficacy of this device for dental radiography cephalometric exposure reduction. The OSLD dosimetric characteristics for 80 kVp cephalometric exposure were first obtained.

HSPB1 Inhibits the Endothelial-to-Mesenchymal Transition to Suppress Pulmonary Fibrosis and Lung Tumorigenesis.

The endothelial-to-mesenchymal transition (EndMT) contributes to cancer, fibrosis, and other pathologic processes. However, the underlying mechanisms are poorly understood. Endothelial HSP1 (HSPB1) protects against cellular stress and has been implicated in cancer progression and pulmonary fibrosis.

Feasibility of Ultra-Thin Fiber-Optic Dosimeters for Radiotherapy Dosimetry.

In this study, prototype ultra-thin fiber-optic dosimeters were fabricated using organic scintillators, wavelength shifting fibers, and plastic optical fibers. The sensor probes of the ultra-thin fiber-optic dosimeters consisted of very thin organic scintillators with thicknesses of 100, 150 and 200 μm. These types of sensors cannot only be used to measure skin or surface doses but also provide depth dose measurements with high spatial resolution.

A Hypoxia-Induced Vascular Endothelial-to-Mesenchymal Transition in Development of Radiation-Induced Pulmonary Fibrosis.

Purpose: Radiation-induced pulmonary fibrosis (RIPF) is a late side effect of thoracic radiotherapy. The purpose of our study was to gain further insight into the development of RIPF.

Experimental Design/results: Here, we observed that irradiation of mouse lungs induced collagen deposition, particularly around blood vessels, in the early phase of RIPF.

Hypoxia/reoxygenation-experienced cancer cell migration and metastasis are regulated by Rap1- and Rac1-GTPase activation via the expression of thymosin beta-4.

Signaling by small guanosine triphosphatases (GTPase), Rap1/Rac1, is one of the major pathways controlling cancer cell migration and tumor metastasis. Thymosin beta-4 (Tβ4), an actin-sequestering protein, has been shown to increase migration of cancer cells. Episodes of hypoxia and re-oxygenation (H/R) are an important phenomenon in tumor microenvironment (TME).

Measurement of Cerenkov radiation induced by the gamma-rays of Co-60 therapy units using wavelength shifting fiber.

In this study, a wavelength shifting fiber that shifts ultra-violet and blue light to green light was employed as a sensor probe of a fiber-optic Cerenkov radiation sensor. In order to characterize Cerenkov radiation generated in the developed wavelength shifting fiber and a plastic optical fiber, spectra and intensities of Cerenkov radiation were measured with a spectrometer. The spectral peaks of light outputs from the wavelength shifting fiber and the plastic optical fiber were measured at wavelengths of 500 and 510 nm, respectively, and the intensity of transmitted light output of the wavelength shifting fiber was 22.

Evaluation of premature senescence and senescence biomarkers in carcinoma cells and xenograft mice exposed to single or fractionated irradiation.

The purpose of the present study was to elucidate whether premature senescence contributes to the outcome of radiotherapy (RT) and to validate senescence biomarkers in vitro and in vivo. Cultured human cancer cell lines and xenografted mice were exposed to single (SR; 2, 6 or 12 Gy) or fractionated radiation (FR; 3 x 2 Gy or 6 x 2 Gy), and premature senescence was assessed using senescence-associated β-galactosidase (SA-β-Gal) activity, hypophosphorylation of pRb and p21 accumulation. A variety of senescence-associated biomarkers including cathepsin D (CD), the eukaryotic translation elongation factors eEF1A1, eEF1B2, decoy receptor 2 and Dec1 were further validated in vivo or in vitro.

Trends of the effective dose distribution of occupational exposures in medical and research departments for KIRAMS in Republic of Korea.

This work proposes the basic reference data of occupational dose management and statistical dose distribution with the classification of radiation work groups though analysis of occupational dose distribution. Data on occupational radiation exposure from medical and scientific usage of radiation in Korea Institute of Radiological and Medical Sciences for the years 2002-11 are presented and evaluated with the characteristic tendency of radiation working groups. The results of occupational radiation exposure were measured by personal dosemeters.

The effect of oxidized low-density lipoprotein (ox-LDL) on radiation-induced endothelial-to-mesenchymal transition.

Purpose: Radiation-induced cardiovascular disease is a potentially severe side-effect of thoracic radiotherapy treatment. Clinically, this delayed side-effect presents as a form of accelerated atherosclerosis several years after irradiation. As general endothelial dysfunction is known to be an initiating event in radiation-induced vascular damage, we examined the effects of radiation on endothelial cells in radiation-induced atherosclerosis.

Dosimetric evaluation of a glass dosimeter for proton beam measurements.

Purpose: The GD-301 radiophotoluminescent glass dosimeter system has recently become commercially available. The purpose of this study was to investigate the dosimetric characteristics (reproducibility, linearity, dose rate, fading, angular dependence, and depth-dose distribution) of this system for clinical dosimetry in a high-energy proton beam and to compare it with lithium fluoride TLD-100.

Materials And Methods: The depth-dose distribution measured with the glass dosimeter was compared to those from GEANT4 Monte-Carlo simulation.

Feasibility study of glass dosimeter for in vivo measurement: dosimetric characterization and clinical application in proton beams.

Purpose: To evaluate the suitability of the GD-301 glass dosimeter for in vivo dose verification in proton therapy.

Methods And Materials: The glass dosimeter was analyzed for its dosimetrics characteristic in proton beam. Dosimeters were calibrated in a water phantom using a stairlike holder specially designed for this study.

Combination effect of cetuximab with radiation in colorectal cancer cells.

Aims And Background: Colorectal cancer (CRC) is one of the commonest malignant disorders and frequently associated with high expression of epidermal growth factor receptor (EGFR), resulting in advanced disease and a poor prognosis. In this study, we investigated the radiosensitizing effects of the selective EGFR inhibitor cetuximab in human CRC cell lines.

Methods: Four human CRC cell lines, CaCo-2, HCT-8, LoVo, and WiDr, were treated with cetuximab and/or radiation.

Anti-tumor effects by a synthetic chalcone compound is mediated by c-Myc-mediated reactive oxygen species production.

Overexpression of c-Myc represents the most frequently deregulated genetic event in cancer, and therefore c-Myc may represent a good molecular target for cancer therapy. The human lung carcinoma cell line, NCI-H1299, shows resistance to conventional cancer treatments, such as ionizing radiation (IR) and cisplatin, while the lung carcinoma cell line, NCI-H460, is sensitive to treatment with these agents. However, when treated with a chalcone compound [toluenesulfonylamido-chalcone, 4'-(p-toluene sulfonyl amino)-3,4-dihydroxy chalcone (TSHDC)], cell death was dramatically induced in NCI-H1299 cells as compared to NCI-H460 cells.

Cryptosporidium parvum: radiation-induced alteration of the oocyst proteome.

Cryptosporidium parvum is a waterborne protozoan parasite that is found intracellularly in host animals, including humans, and causes severe diarrhea, which can lead to the death of an immunocompromised individual. Previously, we found that this organism is highly radioresistant as it can productively infect mice after exposure to a 10-kGy dose of γ-radiation. To understand how C.

Long term follow-up results of external beam radiotherapy as primary treatment for retinoblastoma.

The authors reviewed their experiences of external beam radiotherapy (EBR) as an initial treatment in retinoblastoma patients to determine its long-term effect on subsequent tumor control and complications. A total of 32 eyes in 25 patients that underwent EBR for retinoblastoma were reviewed retrospectively. The patients consisted of 21 boys and 4 girls of median age at treatment of 7.

Trends for the past 10 years and international comparisons of the structure of Korean radiation oncology.

Objective: Study aims include determination of nationwide structural characteristics of radiation oncology facilities, types of radiation therapy equipment, availability of human resources and trends and comparisons with previous surveys.

Methods: An annual nationwide survey was conducted to collect the statistics of infrastructure since 1997. All requested questionnaires have been identical for 10 years.

Clinical characteristics of radiation oncology in Korea during past 10 years.

To understand trends in the clinical characteristics of radiation oncology over the last 10 yr in Korea, annual survey questionnaires were sent to all of Korean radiation oncology facilities since 1990. Questionnaires addressed basic radiation therapy facilities and the clinical information. Responses were obtained from all facilities, and data collected from 1997 to 2006 was analyzed.

Effect of ablated hippocampal neurogenesis on the formation and extinction of contextual fear memory.

Newborn neurons in the subgranular zone (SGZ) of the hippocampus incorporate into the dentate gyrus and mature. Numerous studies have focused on hippocampal neurogenesis because of its importance in learning and memory. However, it is largely unknown whether hippocampal neurogenesis is involved in memory extinction per se.

Stereotactic body radiation therapy in patients with pelvic recurrence from rectal carcinoma.

Objective: To investigate the clinical applications of stereotactic body radiation therapy (SBRT) using the CyberKnife system for pelvic recurrence from rectal cancer with a focus on survival and toxicity.

Methods: Between 2002 and 2006, 23 patients with recurrent rectal cancer were treated with SBRT at our institution. The median follow-up was 31 months.

A cytogenetic study of Korean native goat bred in the nuclear power plant using the micronucleus assay.

Cytogenetic and hematological analysis was performed on the peripheral blood lymphocytes (PBLs) obtained from Korean native goats bred in two nuclear power plants (Wolsong and Uljin) and a control area. The frequencies of gamma-ray-induced micronuclei (MN) in the cytokinesis-blocked (CB) lymphocytes at several doses were measured in three Korean native goats. The measurements performed after irradiation showed dose-related increases in the MN frequency in each of the donors.