Induction of apoptosis in gynecologic cancer cells by the soluble IGF-I receptor.

1)为了评价IGF-I受体阻断在妇科恶性肿瘤中的抗肿瘤作用，我们将反义mRNA表达载体转染人宫颈癌衍生细胞系SiHa、HeLa S3和C33A，建立稳定的转化子。反义蛋白的引入对单层生长有轻微抑制作用，对软琼脂不依赖锚定生长有明显抑制作用，对裸鼠的致瘤性有明显抑制作用。这些结果发表在第90届AACR年会上（Philadelphia PA， USA），并发表在《癌症研究》杂志上。2)然后我们尝试使用具有旁观者效应的可溶性IGF-I受体，这将在临床应用中具有优势。我们稳定地转染了人卵巢癌源性细胞系CaOV-3的可溶性igf - 1受体。从总细胞裂解物和条件培养基中检测到可溶性受体为70kDa蛋白。可溶性IGF-I受体克隆的非锚定生长受到强烈抑制，转染克隆的条件培养基表现出旁观者效应。转染的克隆消除了裸鼠的致瘤性，亲本细胞与转染的克隆共培养在体内表现出旁观者效应。克隆实验表明，转染后的克隆对紫杉醇具有较高的敏感性。紫杉醇处理后的凋亡细胞百分比显著高于转染后的克隆；表明igf - 1受体抗凋亡活性的丧失导致了这种作用。这些结果已在第五届igf国际研讨会（英国布莱顿）、AACR第92届年会（美国新奥尔良）上发表，并已提交出版

1) In order to evaluate the anti-tumor effect of the IGF-I receptor blockage in gynecologic malignancies, We transfected an antisense mRNA expression vector into human cervical cancer derived cell lines, SiHa, HeLa S3, and C33A and established stable transformants. Introduction of the antisense slightly inhibited growth in mono-layer and makedly inhibited anchorage-independent growth in soft agar and tumorigenicity in nude mice. These results were presented at the 90th annual meeting of AACR (Philadelphia PA, USA) and published in Cancer Research.2) Then we tried to use the soluble IGF-I receptor with a bystander effect that would be an advantage in clinical applications. We stably transfected the soluble IGF-I receptor in human ovarian carcinoma derived cell line CaOV-3. The soluble receptor was detected as a 70kDa protein from total cell lysates as well as conditioned media. Anchorage-independent growth of the soluble IGF-I receptor clones was strongly inhibited and conditioned media from transfected clones showed bystander effects. Tumorigenicity in nude mice was abrogated in transfected clones and co-culture of the parental cells with transfected clones showed bystander effects in vivo. Chemosensitivity against paclitaxel was tested by clonogenic assay and transfected clones showed much higher sensitivities. Percentages of the apoptotic cells after paclitaxel treatment were significantly higher in transfected clones ; indicating the abrogation of the anti-apoptotic activity of the IGF-I receptor caused this effect. These results were presented at the 5th International Symposium on IGFs (Brighton, UK), the 92nd annual meeting of AACR (New Orleans LA, USA) and submitted for publication