氧化砷诱导食管癌细胞系细胞凋亡的形态学研究

Morphologic study on apoptosis of esophageal carcinoma cell line induced by arsenic trioxide

目的在氧化砷（As2O3）作用于食管癌细胞株EC8712过程中，用光镜和电镜观察培养细胞凋亡的形态改变方法ECh712于199培养基常规培养，以3μmolAs2O3作用于细胞，72h收获细胞，作光镜（HE染色，TUNEL标记）、透射电镜和流式细胞仪检查.结果3μmolAs2O3作用72h，出现许多凋亡细胞，培养细胞部分变圆，脱落.在光镜下HE染色观察2种凋亡细胞.一种核小；圆形，致密呈固缩核、和核碎,另一种胞质红染，染色质凝集，二者TUNEL标记阳性．流式细胞仪检测有凋亡峰出现（亚G1／G0峰）．电镜检查有二种凋亡类型.一呈典型凋亡细胞核改变；在早期染色质凝集成块状，细胞器保存完好.第二期，随着染色质改变，细胞核变圆，饱满，核膜完整，染色质靠边，大块染色质，构成车轮状或半月状.核膜变性解体，使染色质逸出．最后细胞变性坏死.凋亡小体易见，小块状球状，膜包或裸露.另一种固缩细胞，细胞皱缩，胞质致密，核电子密度高.结论光镜和电镜检查结果证实As2O3可以诱导食管癌细胞系ECh712细胞凋亡，因此As2O3可作为食管癌辅助治疗药物．

AIM To observe the morphological changes of the cell apoptosis of esophageal carcinoma cell line EC8712indued by arsenic trioxide.METHODS EC8712 cells routinely cultured in 199 medium and acted under 3μmol AS2O3 were harvested atfer 72hours, and then HE-stained, TUNEL labelled and examined by transmitting electron microscope and flow cytometry.RESULTS When adding As2O3(3μnol) to EC8712 cells for 72 hours, many apoptotic cells appeared. Under light microscope, two kinds of apoptotic cells were seen after HE-staining. One was condened, small-sized and rounded in shape with nucleus dened.The other cells had eosin stained cytoplasm, chromatin agglutinated and the nucleolus existed. Th6 nuclei of the apoptotic cells were positive by labelling with TUNEL kit. The apoptotic peak was identified by flow cytometry. Under electron microscope, two kinds Of apoptotic modes were also seen. At early stage of apoptosis, the chromatin of the nucleus agglutinated to piece and the organelles in the cytoplasm preserved complete. At second stage,following the change of chromatin, the nucleus became round, full with small pieces of chromatin sticked closely to the nuclear membrane, while the large clumps of chromatin made the nucleus look-like a wheel or a crescent mass. Most of the apoptotic cells showed disintegration of nuclear membrane, from which the chromatin flew out. At the final stage, the apoptotic cells showed degeneration or necrosis. Apoptotic bodies were easily seen, that they were densed, piece-like or balllike, naked or capsulated. In the other mode of apoptosis,pyknotic cells showed cell shrinkage, cytoplasm condensation, high electron density and gradual solidification of cell nucleus.CONCLUSION Apoptosis of esophageal carcinoma cell line EC8712 can be induced by As2O3, which may be used as supplementary therapeutic for the treatment of the esophageal carcinoma.