轻稀土化合物抑瘤作用的研究

为了探讨稀土与肿瘤的关系，作者按卫生部抗肿瘤药物体内药效实验规程，对混合轻稀土进行了体内抑瘤实验，结果在３２ｍｇ／ｋｇ剂量下其抑瘤率对Ｓ１８０肉瘤为３９．８７％，对Ｌｅｗｉｓ肺癌为３６．８２％，有明显的抑瘤作用，超过了有效药物抑瘤标准（３０％）；体外抑瘤实验用ＭＴＴ法、３Ｈ－ＴｄＲ掺入法及细胞倍增时间的测定结果，均证明对人体羊膜细胞有促生长作用，而对人白血病瘤细胞Ｋ５６２有抑制作用。抗诱变实验结果表明稀土对ＭＭＣ诱发Ｖ７９细胞微核率低于对照组（Ｐ＜０．０５），显示出抗诱变性。抗肿瘤免疫实验以１２５Ｉ－ｕｄＲ标记法测定ＮＫ细胞活力，表明稀土在３２ｍｇ／ｋｇ时对ＮＫ细胞有明显激活作用；用孔雀绿比色法测定Ｍψ特异吞噬功能结果表明稀土能促进巨噬细胞特异吞噬功能的提高，并具有拮抗氢化可的松抑制巨噬细胞吞噬的作用。应用电子顺磁共振（ＥＳＲ）自旋捕获技术测定稀土对温石棉产生羟基自由基（ＯＨ·）的影响，发现有抑制作用。电泳观察发现稀土能水解断裂人胃癌细胞ＤＮＡ。还对我国最大的稀土生产厂进行了稀土作业工人１７年回顾性肿瘤流行病学调查，稀土组与对照组的患病率分别为１９．７８５９／１０５和９５．４７２５／１０５，标化患病率为３０

Study on antitumor effeet of mixed light rare earth compounds

The relationship between rare earth compound(RE) and cancer was studied.RE could inhibit the growth of S180 sarcoma and Lewis lung cancer in vivo at dose of 32mg/kg.The inhibitory rates were 39.87%and 36. 82%,respectively. In vitro RE could promote the proliferation of the human foetal membranes cell(FL)and suppress human leukemoid cell(K562).RE could inhibit the increase of micronucleus in V79 cell induced by MMC(P<0.05)The activity of NK cell increased.after stimulated by RE at dose of 32mg/kg.The special phagocytosis of macrophage was promoted and the dose-responese relation was gained.We also observed the OH·generation ability of mong chrysotile fibers which were treated by RE with ESR spin trapping.It got weaker after treated.RE could catalyze hydrolysis of human gastric cancer cell DNA.We made an epidemiology investigation on workers exposed to RE. The results showed low incidence of cancer.It was proved that RE could inhibit and prevent the growth of cancer RE which we studied was non-radioactive light RE compounds.