Yokohira Masanao, Hashimoto Nozomi, Yamakawa Keiko, Suzuki Satoshi, Saoo Kousuke, Kuno Toshiya, Imaida Katsumi
Onco-Pathology, Department of Pathology and Host-Defense, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
J Toxicol Pathol. 2009 Sep;22(3):179-85. doi: 10.1293/tox.22.179. Epub 2009 Oct 15.
The purpose of the present study was to investigate the effects of inflammation, induced by intratracheal instillation (i.t.) of quartz as an environmental factor in the lung or drinking of dextran sulfate sodium (DSS) as an environmental factor in the colon on lung tumors in female A/J mice initiated with NNK. For comparison, colonic preneoplastic lesions, aberrant crypt foci (ACF), were also assessed. A/J mice at 6 weeks of age were divided into 5 groups, and Groups 1, 2 and 3 were pretreated with NNK (2 mg / 0.1 ml saline / mouse, intraperitoneal injection) at week 0. For a week, 2% DSS in drinking water was administered to the mice in Groups 2 and 4 beginning in week 1. In week 2, the mice of Groups 3 and 5 were exposed to intratracheal instillation of quartz (0.1 mg/rat) suspended in 25 μl saline. The experiment was terminated after 16 weeks. The results for the lung tumors and colonic ACFs showed a lack of modifying effects of the inflammation in either site. Hematologically and histopathologically, the inflammation induced by 0.1 mg quartz in the lung and 2% DSS in the colon was lacking or only mild at the end of 16 weeks. These results suggest that there may be differences in sensitivity to inflammation that determine tumor promoting potential.
本研究的目的是探讨通过气管内滴注石英(作为肺部的环境因素)或饮用硫酸葡聚糖钠(DSS,作为结肠的环境因素)诱导的炎症对用NNK启动的雌性A/J小鼠肺部肿瘤的影响。为了进行比较,还评估了结肠癌前病变——异常隐窝灶(ACF)。6周龄的A/J小鼠被分为5组,第1、2和3组在第0周用NNK(2mg / 0.1ml生理盐水/只小鼠,腹腔注射)进行预处理。从第1周开始,第2和4组的小鼠饮用含2% DSS的水,持续一周。在第2周,第3和5组的小鼠接受气管内滴注悬浮于25μl生理盐水中的石英(0.1mg/只大鼠)。16周后实验结束。肺部肿瘤和结肠ACF的结果显示,任一部位的炎症均无修饰作用。血液学和组织病理学检查显示,在16周结束时,肺部0.1mg石英和结肠2% DSS诱导的炎症不存在或仅为轻度。这些结果表明,对炎症的敏感性可能存在差异,这决定了肿瘤促进潜力。