【摘要】 目的:探讨维甲酸受体β(nuclearretinoicacidreceptorbeta,RARβ)基因联合全反式维甲酸(alltransretinoicacid,ATRA)对荷口腔鳞癌裸鼠体内抗癌作用的机制。方法:ATRA、RARβ+ATRA和生理盐水分别治疗舌鳞癌移植瘤裸鼠4周,第四周末处死所有20只动物,取部分肿瘤组织固定后行常规病理切片,HE染色后光镜下观察并照相。切取部分肿瘤组织固定后行超薄切片和染色,透射电镜观察并照相记录。取部分新鲜组织,应用机械法制备单细胞悬液,PI染色后流式细胞仪检测细胞凋亡,Lysis软件分析凋亡细胞比例。结果:肿瘤组织剖面呈鱼肉状、质脆,中央有坏死;光镜下见空白对照组肿瘤细胞增殖旺盛,细胞呈不均一圆形,核浆比例大,核染色深,核分裂相较多;ATRA和RARβ+ATRA治疗组细胞核分裂少见;ATRA处理组可见部分细胞核固缩;RARβ+ATRA治疗组有较多细胞出现核固缩,呈片状分布,偶见细胞片状坏死。空白对照组肿瘤细胞平均凋亡率为6.3%,ATRA组和RARβ+ATRA组凋亡率分别为16.4%和16.6%。两者与对照组相比凋亡率明显增高(P<0.05),但两处理组差别不明显。透射电镜下空白对照组肿瘤细胞呈多角形,核大,核仁多,分裂相较多,凋亡细胞极少。ATRA组可见散在的凋亡细胞,表现为细胞皱缩,变小、变圆,染色质固缩、边聚,细胞浆浓缩。RARβ+ATRA组可见较更多还原

【Abstract】 Objective: The purpose of this study was to determine the antitumor effect of RARβ gene and ATRA on human oral squamous carcinoma cell xenograft in athymic nude mice and to investigate the mechanism of growth inhibition of tumor in vivo. Methods: At the end of the treatment, all the animals implanted with Tca8113 cells, named control group, ATRA group and RARβ+ATRA group were killed. Tumors were surgically excised. Some samples were fixed in 10% formalin for 24 to 48 hours before being embedded in paraffin. Hematoxylin and erosin staining were performed for regular pathological examination. Some samples were also prepared for electronic microscopic observation and flow cytometry test. Lysis precedure was used to analyze cell apoptotic ratio. Results: The sections of the tumors looked like the flesh of fish. There was necrosis in the center of the tumor. The tumor tissue was very crisp. The shapes of the tumor cells were round with condensly dyed nucleus, but the sizes of the cells were different. The ratio between nucleus and plasma was large. The tumor cells proliferated vigorously in the control group with more mitotic nucleus, while the mitotic cells were therapy less frequently in the two treated groups. There were pieces of cells showing karyopyknosis in the RARβ+ATRA treated group. Occasionally, there were pieces of necrotic cells in this group. Flow cytometry assay was used in apoptic examination. The average percentage of apoptotic cells was 6.3% in control group, but 16.4% and 16.6% of the cells in ATRA and ATRA+RARβ group,respectively. Electronic microscopic observation revealed that there were more apoptotic cells in treated groups than in control group. The typical morphological changes included cell shrink, smaller size, cytoplasma vacuolization, nuclear fragmentation with condensed chromatin and chrosome accumulated around nuclear membrane. There were pieces of apoptotic cells on the tissue sections of the tumor in ATRA+RARβ group. Conclusion: Combined treatment with RARβgene and ATRA may inhibit growth through inducing tumor cells apoptosis mainly.更多还原