人结直肠癌细胞周期各时相中双微体存在形式及复制分离时期的分析  

Analysis of the forms and replication separation stages of DMs in the cell cycle at different phases of colorectal cancer cells

作　　者：朱世豪 董科显 蔡梦迪 杜硕萌 张硕鹏 傅松滨 ZHU Shihao;DONG Kexian;CAI Mengdi;DU Shuomeng;ZHANG Shuopeng;FU Songbin(Key Laboratory of Preservation of Human Genetic Resources and Disease Control in China,Ministry of Education,Harbin 150081,China;Laboratory of Medical Genetics,Harbin Medical University)

机构地区：[1]中国遗传资源保护与疾病防控教育部重点实验室,哈尔滨150081 [2]哈尔滨医科大学医学遗传学研究室

出　　处：《实用肿瘤学杂志》2024年第3期149-156,共8页Practical Oncology Journal

基　　金：国家自然科学基金(编号:30370783)。

摘　　要：目的探究双微体(Double minute chromosomes,DMs)在肿瘤细胞周期各时相内的主要存在形式,明确DMs的复制、分离时相。方法通过无血清饥饿法阻滞人结直肠癌细胞COLO 320DM周期进展后,取花萼海绵体诱癌素A(Calyculin-A)诱导间期细胞以染色质超前凝集制备核型样本。用秋水仙素处理COLO 320DM细胞以获取有丝分裂(M)期细胞进行核型分析。在普通光学显微镜下观察并拍摄DNA合成前期(G1期)、DNA合成后期(G2期)、M中期、M后期和M末期核型,并统计DMs数量。结果DMs在G1期、M后期和M末期时相细胞中主要以单体形式存在;在G2期和M中期时相细胞中主要以双体形式存在。结论单体型DMs在S期发生复制后由单体转变为双体,双体型DMs在M后期完成分离并由双体转变为单体。Objective The study aimed to explore the main forms of double minute chromosomes(DMs)in the cell cycle of colorectal cancer at different phases,and to clarify the replication and separation phases of DMs.Methods After using serum-free starvation to block the progression of cell cycle in colorectal cancer COLO 320DM cells,Calyculin-A was used to induce interphase cells to prepare karyotype samples through advanced chromatin condensation.COLO 320DM cells were treated with colchicine to obtain mitosis(M)phase cells for karyotype analysis.The karyotypes of cells at the early stage of DNA synthesis(G1 phase),the late stage of DNA synthesis(G2 phase),metaphase(M-mid),anaphase(M-late),and telophase(M-ter)of mitosis were observed and photographed under a regular optical microscope,and counted the number of DMs.Results DMs mainly existed in monotypic form at the G1 phase,M-late phase and M-ter phase of cells.In the G2 and M-mid phases of cells,DMs mainly existed in a diploid form.Conclusion Monomeric DMs undergo replication in the S phase and transform from monomers to diploids,while diploid DMs in the M-late phase complete separation and transition from diploids to monomers.

关 键 词：双微体 染色体超前凝集 有丝分裂 细胞周期 核型 

分 类 号：R394[医药卫生—医学遗传学]