Kanazawa K, Ohno M, Tanaka K, Honma S, Tanaka K, Yoshiya N, Takeuchi S
Gan To Kagaku Ryoho. 1983 Oct;10(10):2217-24.
The cancer chemotherapy combined with immuno-potentiators, OK-432 and/or PSK, had yielded an improvement in survival rate of choriocarcinoma patients in our clinic as previously reported elsewhere. In the present study, for the purpose of evaluation of direct antitumor activity of OK-432 and PSK, inhibitory effects of the drugs on cell growth of GCH-1 and GCH-2 (in vitro cell lines of human choriocarcinoma) were analyzed referring to those of MTX (methotrexate) and Act-D (actinomycin D). 1) IC 50 (50% inhibitory concentration) of OK-432 and of PSK were 0.56 KE/ml on GCH-1 and 0.48 KE/ml on GCH-2, and 310 micrograms/ml on GCH-1 and 460 micrograms/ml on GCH-2, respectively. 2) The morphological changes of the target cells, observed by light and electron microscope, induced by OK-432 and PSK seemed to be not different from those by MTX and Act-D. 3) Serial changes of hCG levels in the culture media in which OK-432 or PSK was added were roughly comparable with those in MTX or Act-D. Thus, the direct antitumor activity of OK-432 and PSK on GCH-1 and GCH-2 was exquisitely weak judging from their IC50 and it was suggested that their direct antitumor effects in vivo might be clinically negligible in choriocarcinoma.
如先前在其他地方所报道的，在我们诊所，癌症化疗联合免疫增强剂OK-432和/或PSK已提高了绒毛膜癌患者的生存率。在本研究中，为了评估OK-432和PSK的直接抗肿瘤活性，参照甲氨蝶呤（MTX）和放线菌素D（Act-D）的作用，分析了这两种药物对GCH-1和GCH-2（人绒毛膜癌的体外细胞系）细胞生长的抑制作用。1）OK-432和PSK对GCH-1的半数抑制浓度（IC50）分别为0.56KE/ml，对GCH-2为0.48KE/ml；对GCH-1的IC50为310μg/ml，对GCH-2为460μg/ml。2）通过光学显微镜和电子显微镜观察到，由OK-432和PSK诱导的靶细胞形态变化似乎与MTX和Act-D诱导的变化没有差异。3）添加OK-432或PSK的培养基中hCG水平的系列变化与MTX或Act-D的大致相当。因此，从IC50判断，OK-432和PSK对GCH-1和GCH-2的直接抗肿瘤活性非常弱，提示它们在体内对绒毛膜癌的直接抗肿瘤作用在临床上可能微不足道。
