Baz A, Henry L, Caravano R, Scherrer K, Bureau J P
Laboratoire de Biologie Cellulaire et Cytogénétique Moléculaire (UPRES-JE 1952), Faculté de Médecine Montpellier-Nîmes, Nîmes, France.
Int J Cancer. 1997 Jul 29;72(3):467-76. doi: 10.1002/(sici)1097-0215(19970729)72:3<467::aid-ijc15>3.0.co;2-9.
The subunit composition of cell-internal and surface prosomes during phorbol myristate acetate (PMA)-induced differentiation of human leukemic T lymphocytes (CCRF-CEM cell line) was studied in relation to clusters of differentiation (CD) markers. PMA inhibited cell growth and decreased the amounts of CD1a and CD4 while CD3, CD8, CD25, CD45, CD57 and MHCI increased it; the p53 anti-oncogene increased while actin levels remained constant. Cells incubated with the inducer PMA for 3 days and placed in fresh inhibitor-free medium resumed growth at a low rate, while the CD values slowly reverted to those of the initial phenotype. The presence and relative amounts of prosome subunits were analyzed by flow cytometry, light and fluorescent microscopy and Western blotting using 3 monoclonal antibodies (p25K, p27K and p30-33K MAbs). The decrease in cytoplasmic antigens on day 3 was remarkable (cells followed for 7 days) while increased surface antigens were observed. Changes in the subcellular distributions of prosome antigens, particularly the p25K and p30-33K subunit, were correlated with a partial arrest of the cell cycle. Interestingly, the composition of cell internal and surface prosomes showed different patterns of change.
在佛波酯肉豆蔻酸酯乙酸盐（PMA）诱导人白血病T淋巴细胞（CCRF - CEM细胞系）分化过程中，研究了细胞内和表面蛋白酶体的亚基组成与分化簇（CD）标志物的关系。PMA抑制细胞生长，降低CD1a和CD4的量，而CD3、CD8、CD25、CD45、CD57和MHC I的量增加；p53抗癌基因增加，而肌动蛋白水平保持不变。用诱导剂PMA孵育3天的细胞置于新鲜的无抑制剂培养基中后以低速率恢复生长，而CD值缓慢恢复到初始表型的值。使用3种单克隆抗体（p25K、p27K和p30 - 33K单克隆抗体）通过流式细胞术、光学和荧光显微镜以及蛋白质免疫印迹分析蛋白酶体亚基的存在和相对量。第3天细胞质抗原的减少很明显（观察细胞7天），同时观察到表面抗原增加。蛋白酶体抗原亚细胞分布的变化，特别是p25K和p30 - 33K亚基，与细胞周期的部分停滞相关。有趣的是，细胞内和表面蛋白酶体的组成显示出不同的变化模式。
