p53基因转染对卵巢癌MDR细胞药物敏感性及恶性表型的影响

研究 ｐ５３基因导入已知内源背景的肿瘤 ＭＤＲ细胞所致的恶性表型和ＭＤＲ表型的改变及两者的关系。方法：用磷酸钙沉淀法将含有野生型及全长反义 ｐ５３ｃＤＮＡ的逆转录病毒载体ｐＤＷｐ５３及 ｐＤＡｐ５３转染病毒包装细胞 ＰＡ３１７，测定病毒滴度。用此病毒感染卵巢癌多药耐药细胞株Ａ２７８０／ＡＤＭ，Ｓｏｕｔｈｅｒｎ Ｂｌｏｔ鉴定，检测转导基因后细胞株的恶性度、多药耐药性等情况。结果：野生型及反义全长ｐ５３ｃＤＮＡ均转入 ＰＡ３１７细胞获得效价为（１－ １．５） Ｘ１０５ＣＦＵ／ｍｌ的前病毒，以此感染卵巢癌多药耐药细胞株Ａ２７８０／ＡＤＭ，Ｓｏｕｔｈｅｍ Ｂｌｏｔ证实ｐ５３基因导入该细胞并整合到基因组ＤＮＡ中，进一步测试观察到：①导入野生型ｐ５３基因的Ａ２７８０／ＡＤＭ细胞生长被抑制、恶性度降低，细胞形态和生长曲线改变，软琼脂集落形成率及裸鼠接种成瘤率降低；②细胞多药耐药性减弱，对ＡＤＭ耐药性下降，Ｐ－ｇｐ表达降低；③反义ｐ５３的导入也对Ａ２７８０／ＡＤＭ恶性度有一定的影响；④野生型ｐ５３导致的ＭＤＲ细胞恶性表型与ＭＤＲ水平的降低似有平行关系。结论：ｐ５３基因对肿瘤细胞ｍｄｒ－ １基因的表达可能起调控作用，ｐ５３发生突变的 Ｍ?

Influence of drug sensitivity and malignant phenotype of ovarian cancer MDR cells transfected with p53 gene

Objective:To study the changes of tumor MDR cell malignant and MDR phenotype caused by transferring into p53 and to explore the relationship between them. Methods:Wild and anti - sense p53 were transfected into ovarian cancer MDR cell strain A2780/ADM was transferred by retrovirus vector and were the virus titre detected . The virus was infected into tumor MDR cell - A2780/ADM. After certificated by Southern blot, its ma- lignancy and multi-drug resistence was detectal. Results: After transfecting wild and anti - sense p53 into ovarian cancer MDR cell strain A2780/ADM by retrovirus vector, the fol- lowing result can be ovserved. The growth of the A2780/ADM cells were inhibited and their malignant degree and nude mice tumor - forming rate became lower. Cellular MDR was less- ened such as the reduction of the resistant ability to ADM and the lowering of the expression of P - gp. Transfection of anti - sense p53 can also influence the malignant degree of A2780/ADM. The malignant phenotype of MDR cells caused by the transfection of WT p53 seems parallelable to the lowering of MDR level. Conclusions: p53 may regulate the expres- sion of tumor cell mdr- 1 gene and MDR phenotype of the p53 mutant. MDR cells trans- fected with wild p53 can be reversed to such a degree which provides direct experimental ev- idence for reversing MDR at molecular level by transfecting p53 into cancer cell.