Doguchi Hiroshi, Saio Masanao, Kuniyoshi Shimpei, Matsuzaki Akiko, Yoshimi Naoki
Department of Pathology and Oncology, Graduate School of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-0125, Japan.
J Toxicol Pathol. 2014 Apr;27(1):67-72. doi: 10.1293/tox.2013-0046. Epub 2014 Apr 30.
The effects of hyperbaric oxygen (HBO) on mouse skin two-stage chemical carcinogenesis were examined. Six-week-old inbred CD-1 female mice were divided into the following five groups: group 1, normoxia and application of 25 nmol 7,12-dimethylbenz[a]anthracene (DMBA) and 8.5 nmol 12-O-tetradecanoylphorbol-13-acetate (TPA) (n=19); group 2, HBO and DMBA/TPA (n=21); group 3, HBO and DMBA/acetone (n=3); group 4, normoxia and acetone (n=3); and group 5, non-treatment group (n=5). HBO was started at the same time as DMBA. Mice were euthanized at 23 weeks after the start of the experiment. Mice in group 2 showed the occurrence of tumors at 8 weeks after the beginning of the experiment, while the occurrence of tumors in mice in group 1 was observed beginning at 9 weeks. There was a difference in occurrence among low-grade papillomas, high-grade papillomas and SCCs in both groups 1 and 2 by the χ (2)-test at end of the experiment (p<0.05). The Ki-67 labeling indices of tumors revealed that the percentages of positive cells in low-grade papillomas in groups 1 and 2 were 15.27 ± 2.54% and 29.67 ± 2.82%, respectively (p<0.01). The results suggested that the tumors in group 2, which was treated with HBO, were more progressive than those in group 1, which was not treated with HBO. In this study, HBO accelerated tumor cell proliferation and advanced tumor progression in skin carcinogenesis by DMBA/TPA.
研究了高压氧（HBO）对小鼠皮肤两阶段化学致癌作用的影响。将六周龄的近交系CD-1雌性小鼠分为以下五组：第1组，常氧，涂抹25 nmol 7,12-二甲基苯并[a]蒽（DMBA）和8.5 nmol 12-O-十四烷酰佛波醇-13-乙酸酯（TPA）（n = 19）；第2组，HBO及DMBA/TPA（n = 21）；第3组，HBO及DMBA/丙酮（n = 3）；第4组，常氧及丙酮（n = 3）；第5组，未处理组（n = 5）。HBO与DMBA同时开始。实验开始23周后对小鼠实施安乐死。第2组小鼠在实验开始8周后出现肿瘤，而第1组小鼠从9周开始观察到肿瘤发生。实验结束时，通过χ（2）检验发现第1组和第2组在低级别乳头状瘤、高级别乳头状瘤和鳞状细胞癌的发生率上存在差异（p<0.05）。肿瘤的Ki-67标记指数显示，第1组和第2组低级别乳头状瘤中的阳性细胞百分比分别为15.27±2.54%和29.67±2.82%（p<0.01）。结果表明，接受HBO治疗的第2组肿瘤比未接受HBO治疗的第1组肿瘤进展更快。在本研究中，HBO加速了DMBA/TPA诱导的皮肤致癌过程中的肿瘤细胞增殖并促进了肿瘤进展。
