U-Youn Lee

Role of protein kinase Cδ in transmitting hypoxia signal to HSF and HIF-1

An hypoxic microenvironment is an important modulator of gene expression in many pathophysiological conditions. In this study, we show a coordinate activation of heat shock transcription factor (HSF) and hypoxia‐inducible factor‐1 (HIF‐1) in RIF tumor cells by hypoxia. Since heat shock protein (hsp) and angiogenic factor genes that are regulated by HSF and HIF‐1 are thought to contribute to the malignant progression of hypoxic tumor cells, it was of our major interest to identify the components that are responsible for the activation of both HSF and HIF‐1. Our finding that a bioflavonoid quercetin (QCT), a well known inhibitor of hsp gene expression, significantly inhibited the transcriptional activation of HSF and HIF‐1 strongly suggests that QCT‐sensitive molecule(s) is involved in the transcriptional activation of HSF and HIF‐1 by hypoxia. Our results revealed that PCKα, δ and ϵ isoforms are expressed in RIF cells, but only PKCδ was specifically translocated to the membrane by hypoxia. Our results also revealed that the translocation of PKCδ was completely abrogated by QCT. Moreover, inhibiting the PKCδ activation, either pharmacologically with phorbol 12‐myristate 13‐acetate or with bisindolymaleimide II or genetically by transient transfection of a dominant negative PKCδ, significantly inhibited the transcriptional activation of HSF and HIF‐1 by hypoxia. These results strongly substantiate a view that the PKCδ isozyme is the QCT‐sensitive molecule that plays an important role in transmitting hypoxia signals to both HSF and HIF‐1. Here we show that the membrane translocation of PKCδ is dependent on the activation of phosphoinositol 3‐kinase (PI3K). Treatment with PI3K inhibitor, wortmannin or LY294002, abrogated not only PKCδ translocation but the subsequent transcriptional activation of HSF and HIF‐1 by hypoxia. Together, our study shows that the PKCδ isozyme acts as a shared component in transmitting hypoxia‐induced signals to both HSF and HIF‐1, and that the upstream regulator of PKCδ is PI3K.

Studies on Immuno-Modulatory and Antitumor Effects of Crude Polysaccharides Extracted from Paecilomyces sinclairii

Neutral salt soluble [0.9% NaCl (Fr. NaCl)], hot water soluble (Fr. HW) and methanol soluble (Fr. MeOH) materials were extracted from Paecilomyces sinclairii. In vitro cytotoxicity tests. Fr. HW was not cytotoxic against MH3T3, Sarcoma 180 and HepG2 cancer cell lines at the concentration of , while HT-29 cell line was cytotoxic at the concentration of . Fr. NaCl and Fr. MeOH were slightly cytotoxic to the cell lines. Intraperitoneal injection with Fr. NaCl and Fr. MeOH exhibited antitumor activity with life prolongation effect of 32.3% in mice inoculated with Sarcoma 180. Fr. NaCl improved proliferation of spleen cells and the immunopotentiation activity of B lymphocyte by increasing spleen cell numbers and the alkaline phosphatase activity by folds, respectively. Fr. NaCl generated of nitric oxide (NO) when cultured with RAW 264.7, a mouse macrophage cell line, at the concentration of , while iipopolysaccharide, a positive control, produced . The Fr. NaCl showed the hightest antitumor effect and activation of B lymphocytes and macrophage. From these results, antitumor effect of P. sinclaitii was likely due to immunopotentiation activity.

Immuno-stimulating and Antitumor Effects on Mouse Sarcoma 180 by Crude Polysaccharides Extracted from Fruiting Body of Hericium erinaceus

Hericium erinaceus, an edible and medicinal mushroom belonging to the Basidiomyco ta family, has been used for curing gastric ulcers and stomach cancers in human beings and is also known to have good inhibitory effects on sarcoma 180 and Ehrlich carcinoma in mice. Neutral saline soluble (0.9% NaCl), hot water soluble and methanol soluble substances (hereinafter referred to as Fr. NaCl, Fr. HW and Fr. MeOH, respectively) were extracted from the fruiting body of the mushroom. In in vitro cytotoxicity tests, crude polysaccharides were not cytotoxic against cell lines such as Sarcoma 180, HepG2, HT-29 and NIH3T3 at concentrations of 10~2,000 μg/ml. Intraperitoneal injection with crude polysaccharides exhibited a life prolongation effect of 29.1~54.1% in mice previously inoculated with Sarcoma 180. Fr. Na increased the numbers of spleen cells by 2.9 fold at a concentration of 50 μg/ml compared with the control. Fr. Na improved the immuno-potentiating activity of B lymphocytes by increasing alkaline phosphatase activity by 5.5 fold compared with the control at a concentration of 200 μg/ml. Fr. NaCl increased the numbers of peritoneal exudate cells and circulating leukocytes by 4 and 2.3 folds at a concentration of 50 mg/kg, respectively. Therefore, the crude polysaccharides extracted from the fruiting body of H. erinaceus could improve antitumor activities in mice.

Antitumor and Immuno-modulatory Effect of Crude Polysaccharides from Fruiting Body of Tremella aurantialba Against Mouse Sarcoma 180

Tremella aurantialba, one of edible and medicinal mushrooms belonging to Tremellaceae of Basidiomycota, has been known to have outstanding curing effects on coughing, tracheitis and hypertension of humans and antitumor activity on the sarcoma 180 and Erhrlich carcinoma of mice. Neutral saline soluble (0.9% NaCl), hot water soluble and methanol soluble substances (hereinafter referred to Fr. NaCl, Fr. HW and Fr. MeOH, respectively) were extracted from fruiting body of the mushroom. In vitro cytotoxicity tests showed that all crude polysaccharides extracted from the fruiting body were not cytotoxic against cancer cell lines such as RAW 309 CR.1 and Sarcoma 180 at the concentration of . Intraperitoneal injection with crude polysaccharides exhibited life prolongation effect of in mice inoculated with Sarcoma 180. Fr. MeOH improved the immunopotentiation activity of B lymphocyte by increasing the alkaline phosphatase activity by 1.16 folds at the concentration of . In case of Fr. HW, the numbers of peritoneal exudate cells and circulating leukocytes were increased by 1.42 and 2.87 folds, respectively.

Vegetative Growth of Four Strains of Hericium erinaceus Collected from Different Habitats

Vegetative growth of four different strains of Hericium erinaceus was observed. The temperature suitable for optimal mycelial growth was determined to be 25°C, with growth observed in the extend temperature range of 20~30°C. The different strains of this mushroom showed distinct pH requirements for their optimum vegetative growth, with the most favorable growth observed at pH 6. Considering vegetative mycelial growth, PDA, YM, Hennerberg, Hamada, and Glucose peptone were the most favorable media, and Czapek Dox, Hoppkins, Glucose tryptone, and Lilly were the most unfavorable media for these mushroom strains. With the exception of lactose, most of the carbon sources assayed demonstrated favorable vegetative growth of H. erinaceus. For mycelial growth, the most suitable nitrogen source was alanine and the most unsuitable was histidine. Oak sawdust medium supplemented with 10~20% rice bran was the best for mycelial growth of the mushroom.

The Characteristics of Cultural Conditions for the Mycelial Growth and Fruiting Body Formation of Paecilomyces sinclairii

매미누꽃동충하초(Paecilomyces sinclairii)를 전라남도 백양사의 인근 숲에서 채집하여 균주를 순수 분리하고 균사의 최적 배양조건과 특성을 조사하였다. 균사생장에 적합한 pH는

Antitumor and Immuno-modulatory Effect Against Mouse Sarcoma 180 of Crude Polysaccharides Extracted from Fruiting Body of Armillaria tabescens

5{\sim}9

The Immuno-Modulatory and Antitumor Effects of Crude Polysaccharides Extracted from Tremella fuciformis

의 범위였으며 pH 8에서 가장 왕성한 균사생장을 보였고, 온도는

Inhibitive Effect of Mouse Sarcoma 180 by Crude Polysaccharide Extracted from Fruiting Body of Aramillaria mellea

25{\circ}C

The Optimal Culture Conditions for the Mycelial Growth of Oudemansiella radicata

가 적합하였다. 균사생장에 가장 적합한 배지는 Hamada 배지였으며 탄소 영양원은 dextrin, 질소 영양원은 glutamine인 것으로 조사되었다. 균사의 생장은 C/N비가 20:1일 때, 옥수수추출물과 우유가 혼합한 배지에서 가장 양호하였다. 자실체는 20%의 누에번데기가 첨가된 현미배지에서 500lux,