Effect of 5-aminolevulinic acid-based photodynamic therapy via reactive oxygen species in human cholangiocarcinoma cells

Cancer cells have been reported to exhibit an enhanced capacity for protoporphyrin IX (PpIX) synthesis facilitated by the administration of 5-aminolevulinic acid (ALA). We investigated the effect of ALA-based photodynamic therapy (PDT) on human cholangiocarcinoma cells (HuCC-T1). Since protoporphyrin IX (PpIX), a metabolite of ALA, can produce reactive oxygen species (ROS) under irradiation and then induce phototoxicity, ALA-based PDT is a promising candidate for the treatment of cholangiocarcinoma. When various concentrations of ALA (0.05–2 mM) were used to treat HuCC-T1 cells for 6 or 24 hours, the intracellular PpIX level increased according to the ALA concentration and treatment time. Furthermore, an increased amount of PpIX in HuCC-T1 cells induced increased production of ROS by irradiation, resulting in increased phototoxicity

Characteristics and treatments of large cystic brain metastasis: radiosurgery and stereotactic aspiration.

Brain metastasis represents one of the most common causes of intracranial tumors in adults, and the incidence of brain metastasis continues to rise due to the increasing survival of cancer patients. Yet, the development of cystic brain metastasis remains a relatively rare occurrence. In this review, we describe the characteristics of cystic brain metastasis and evaluate the combined use of stereotactic aspiration and radiosurgery in treating large cystic brain metastasis. The results of several studies show that stereotactic radiosurgery produces comparable local tumor control and survival rates as other surgery protocols. When the size of the tumor interferes with radiosurgery, stereotactic aspiration of the metastasis should be considered to reduce the target volume as well as decreasing the chance of radiation induced necrosis and providing symptomatic relief from mass effect. The combined use of stereotactic aspiration and radiosurgery has strong implications in improving patient outcomes

Doxorubicin-incorporated polymeric micelles composed of dextran-b-poly(DL-lactide-co-glycolide) copolymer

Young-Il Jeong1,*, Do Hyung Kim1,2,*, Chung-Wook Chung1, Jin-Ju Yoo1, Kyung Ha Choi1, Cy Hyun Kim1,2, Seung Hee Ha1, Dae Hwan Kang1,2 1National Research and Development Center for Hepatobiliary Cancer, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea, Research Institute for Convergence of Biomedical Science and Technology, 2School of Medicine, Pusan National University, Yangsan, Republic of Korea*These authors contributed equally to this work.Background: Polymeric micelles using amphiphilic macromolecules are promising vehicles for antitumor targeting. In this study, we prepared anticancer agent-incorporated polymeric micelles using novel block copolymer.Methods: We synthesized a block copolymer composed of dextran and poly (DL-lactide-co-glycolide) (DexbLG) for antitumor drug delivery. Doxorubicin was selected as the anticancer drug, and was incorporated into polymeric micelles by dialysis. Polymeric micelles were observed by transmission electron microscopy to be spherical and smaller than 100 nm, with a narrow size distribution. The particle size of doxorubicin-incorporated polymeric micelles increased with increasing drug content. Higher initial drug feeding also increased the drug content. Results: During the drug-release study, an initial burst release of doxorubicin was observed for 10 hours, and doxorubicin was continuously released over 4 days. To investigate the in vitro anticancer effects of the polymeric micelles, doxorubicin-resistant HuCC-T1 cells were treated with a very high concentration of doxorubicin. In an antiproliferation study, the polymeric micelles showed higher cytotoxicity to doxorubicin-resistant HuCC-T1 cells than free doxorubicin, indicating that the polymeric micelles were effectively engulfed by tumor cells, while free doxorubicin hardly penetrated the tumor cell membrane. On confocal laser scanning microscopy, free doxorubicin expressed very weak fluorescence intensity, while the polymeric micelles expressed strong red fluorescence. Furthermore, in flow cytometric analysis, fluorescence intensity of polymeric micelles was almost twice as high than with free doxorubicin.Conclusion: DexbLG polymeric micelles incorporating doxorubicin are promising vehicles for antitumor drug targeting.Keywords: dextran, polymeric micelle, block copolymer, poly(DL-lactide-co-glycolide

A New Hardware Correlator in Korea: Performance Evaluation using KVN observations

We report results of the performance evaluation of a new hardware correlator in Korea, the Daejeon correlator, developed by the Korea Astronomy and Space Science Institute (KASI) and the National Astronomical Observatory of Japan (NAOJ). We conducted Very Long Baseline Interferometry (VLBI) observations at 22~GHz with the Korean VLBI Network (KVN) in Korea and the VLBI Exploration of Radio Astrometry (VERA) in Japan, and correlated the aquired data with the Daejeon correlator. For evaluating the performance of the new hardware correlator, we compared the correlation outputs from the Daejeon correlator for KVN observations with those from a software correlator, the Distributed FX (DiFX). We investigated the correlated flux densities and brightness distributions of extragalactic compact radio sources. The comparison of the two correlator outputs show that they are consistent with each other within $<8\%$, which is comparable with the amplitude calibration uncertainties of KVN observations at 22~GHz. We also found that the 8\% difference in flux density is caused mainly by (a) the difference in the way of fringe phase tracking between the DiFX software correlator and the Daejeon hardware correlator, and (b) an unusual pattern (a double-layer pattern) of the amplitude correlation output from the Daejeon correlator. The visibility amplitude loss by the double-layer pattern is as small as 3\%. We conclude that the new hardware correlator produces reasonable correlation outputs for continuum observations, which are consistent with the outputs from the DiFX software correlator.Comment: 13 pagee, 9 figures, 3 tables, to appear in JKAS (received February 9, 2015; accepted March 16, 2015

Anti-proliferative effects of Bifidobacterium adolescentis SPM0212 extract on human colon cancer cell lines

<p>Abstract</p> <p>Background</p> <p>Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as anti-tumor activity. The aim of the present work was to study the growth inhibition of tumor cells by butanol extract of <it>Bifidobacterium adolescentis </it>isolated from healthy young Koreans.</p> <p>Methods</p> <p>The anti-proliferative activity of <it>B. adolescentis </it>isolates was assessed by XTT assays on three human colon cancer cell lines (Caco-2, HT-29, and SW480). The effects of <it>B. adolescentis </it>SPM0212 butanol extract on tumor necrosis factor-α (TNF-α) and nitric oxide (NO) production were tested using the murine macrophage RAW 264.7 cell line.</p> <p>Results</p> <p>The butanol extract of <it>B. adolescentis </it>SPM0212 dose-dependently inhibited the growth of Caco-2, HT-29, and SW480 cells by 70%, 30%, and 40%, respectively, at 200 μg/mL. Additionally, the butanol extract of <it>B. adolescentis </it>SPM0212 induced macrophage activation and significantly increased the production of TNF-α and NO, which regulate immune modulation and are cytotoxic to tumor cells.</p> <p>Conclusion</p> <p>The butanol extract of <it>B. adolescentis </it>SPM0212 increased activity of the host immune system and may improve human health by helping to prevent colon cancer as a biological response modifier.</p