Effect of long-term treatment with extract of areca nut (ANE) or ANE 30-100K on leukemia T cell and oral squamous cell carcinoma

• Main Authors: Pin-yan Lin, 林品妍
• Other Authors: Mei-Huei Lin
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/hj3kkt

碩士 === 嘉南藥理科技大學 === 生物科技系暨研究所 === 100 === Areca nut (AN) is a human carcinogen responsible for high oral cancer incidence in Taiwan. More than 70% patients keep on AN chewing when they took medical treatment in Chi Mei Medical Center. It is thus reasonable to speculate that their oral tumor cells, including lymphocytic and epithelial origins, have received a constant and long-term stimulation from AN. To simulate this in vivo stimulation and observe its on these cells, we subjected Jurkat leukemia T and oral epidermoid carcinoma Meng-1 (OECM-1) cells to long-term treatment with noncytotoxic concentrations of AN extract (ANE) or partially purified 30-100 kDa fraction of ANE (ANE 30-100K) and analyze the effects of these treatment on these cells. The results have demonstrated that both ANE- and ANE 30-100K-selected Jurkat T cells exhibited stronger resistance to low oxygen as well as to cisplatin and 5-fluorouracil (5-FU) as compared to non-selected parental cells. To access the possible mechanism, we next searched for upregulated proteins presumed to responsible for such phenotypic changes in these selected cells. By using immunoblotting or two-dimensional gel electrophoresis and liquid chromatography-mass spectrophotometer (LC-MASS), expression level of DRAM/LC3-II and secretion peroxiredoxin-1 (PRDX-1) were identified to be elevated in both selected cells. Immunohistochemistry revealed that PRDX-1 protein is mainly localized at epithelial layer of normal tissues but is expressed in most tumor cells. Moreover, after comparison of 4 pairs of OSCC tissues from AN and non-AN users, our preliminary data indicate on elevated expression level of PRDX1 in the specimens from AN users. In addition, ANE 30-100K also stimulated PRDX-1 expression in non-tumor oral fibroblasts (CMT-415) in a concentration- dependent manner. We are currently try to inhibit PRDX-1 by siRNA to assess whether this enzyme contribute to increase resistance of low oxygen and drugs in both selected cells.