放射敏感性不同的鼻咽癌细胞DNA倍体及细胞周期分布

Distribution of DNA ploidy and cell cycle in nasopharyngeal carcinoma cells with different radiosensitivity

目的 研究不同放射敏感潜能的人鼻咽癌细胞亚克隆株F1、S1的DNA倍体及细胞周期分布,并探讨与放射敏感性异质性的关系。方法 采用细胞培养及裸鼠体内实验,用Feulgen染色法和图像分析方法观察F1、S1细胞及其裸鼠移植瘤的DNA倍体及细胞周期的分布情况。结果 F1、S1细胞及其裸鼠移植瘤均为异倍体细胞或肿瘤。F1细胞及裸鼠移植瘤DNA含量、5C、>5C比S1组高(P<0.01),F1细胞及裸鼠移植瘤3-4C比例低于相应S1组(P<0.01)。F1细胞及其裸鼠移植瘤G2M比例均高于相应S1组,G0G1期低于S1组(P<0.05-0.01),F1细胞的S期比例低于S1细胞(P<0.01)。结论 F1DNA含量较高、倍体分布较广而右移,较多细胞处于对放射线敏感的G2M期,S1DNA含量较低、倍体分布较窄,较多细胞处于G0G1期和S期。DNA倍体及细胞周期分布地不同可能是F1、S1存在放射敏感性差异的原因之一。

Objective To compare the DNA ploidy and cell cycle distribution of human nasopharyngeal carcinoma subclones F 1 and S 1 with different radiosensitivity, and to study the relationship of radiosensitive heterogeneity with DNA ploidy and cell cycle distribution. Methods Cell culture and nude mice experiment in vivo were used, F 1, S 1 and nude mice transplanted tumors were analyzed for DNA ploidy and cell cycle distribution by feulgen staining and image analysis.Results F 1, S 1 and xenografts were aneuploidy. DNA content, 5C and >5C of F 1were higher than those of S 1 (P<0.01). 3-4C in F 1 and transplanted tumors were lower than in S 1 groups (P<0.01). G 2/M phase of F 1 and transplanted tumors were both higher than those of S 1 groups, G 0/G 1 phase of F 1 and transplanted tumors were lower than those of S 1 groups (P<0.01-0.05). S phase of F 1 cell was lower than of S 1 cell(P<0.01).Conclusion F 1 presented higher DNA content, wider ploidy distribution and shifted to right with more cells in G 2/M phase which was sensitive to radiation, S 1 presented lower DNA content, narrower ploidy distribution with more cells in G 0/G 1 and S phase. Different distribution of DNA ploidy and cell cycle may be one of the reasons of different radiosensitivity with F 1 and S 1.