Ember I, Kiss I, Vermes E
Department of Preventive Medicine, University Medical School of Pécs, Hungary.
In Vivo. 1998 Mar-Apr;12(2):201-7.
Cyclophosphamide (CP) is a widely used chemotherapeutic drug, with proven carcinogenic effects. Secondary tumours induced by CP are kidney tumours in humans and haemopoietic malignancies in rodents. Previous experiments have shown its effect on H-ras, c-myc and p53 gene expression in long term in vivo experiments. Our model was developed to analyse the events in the first 24 hours after the administration of CP in short term experiments. The expression of Ha -ras, c-myc and p53 was investigated in the target organs during and up to 24 hours after the administration, at 0.25, 0.5, 1, 6, 12 and 24 h. Since the majority of CP-induced tumours are leukemias and lymphomas in the CBA/Ca mouse model, RNA was obtained from the thymus and the spleen. The results show that p53 is strongly expressed in the thymus during the focused period. On the other hand, the samples were subjected to in situ hybridisation and compared with the results of in situ hybridisation of lung and liver samples. Comparing the results of total RNA and in situ hybridisation should prove useful if the total RNA signal is too weak or not detectable at all. The in situ hybridisation picture showed many positive cells without high expression of oncogenes. Further flow-cytometric studies are necessary to provide a full explanation of the mechanism of CP induced changes.
环磷酰胺（CP）是一种广泛使用的化疗药物，已证实具有致癌作用。CP诱导的继发性肿瘤在人类中是肾肿瘤，在啮齿动物中是造血系统恶性肿瘤。先前的实验在长期体内实验中显示了其对H-ras、c-myc和p53基因表达的影响。我们开发了该模型以在短期实验中分析CP给药后最初24小时内的事件。在给药后0.25、0.5、1、6、12和24小时期间及直至24小时，研究了靶器官中Ha-ras、c-myc和p53的表达。由于在CBA/Ca小鼠模型中，大多数CP诱导的肿瘤是白血病和淋巴瘤，因此从胸腺和脾脏中获取RNA。结果表明，在关注期间p53在胸腺中强烈表达。另一方面，对样本进行原位杂交，并与肺和肝样本的原位杂交结果进行比较。如果总RNA信号太弱或根本无法检测到，比较总RNA和原位杂交的结果应该会很有用。原位杂交图像显示许多阳性细胞，但癌基因没有高表达。需要进一步的流式细胞术研究来全面解释CP诱导变化的机制。
