肺腺癌A549细胞CD133~+CD44~+表型在裸鼠体内成瘤能力的研究

目的 探讨肿瘤标志物CD133和CD44的表达与人肺腺癌A549细胞株在裸鼠体内形成肿瘤能力的关系.方法 使用单细胞克隆的方法 ,筛选出能够持续增殖分裂的肿瘤细胞,应用免疫荧光方法 和流式细胞仪检测CD133和CD44在具有增殖分裂能力的A549细胞和普通A549肿瘤细胞的表达情况;按表达结果 对A549细胞进行分组,应用单克隆方法 对各组细胞进行培养,并按不间密度注射于裸鼠皮下,观察各个组别的成瘤能力.结果 (1)在倒置显微镜下观察肿瘤细胞生长情况,发现多数细胞死亡,1周后仅有4.11%的细胞能够增殖分裂形成克隆.(2)具有增殖分裂能力肿瘤细胞的免疫荧光结果 :CD133阳性率为19.0%,CD44阳性率为57.0%;普通A549肿瘤细胞免疫荧光结果 :CD133阳性率为2.5%,CD44阳性率为34.0%;具有分裂增殖能力的肿瘤细胞CD133和CD44阳性表达率显著高于普通A549肿瘤细胞(P<0.01).(3)裸鼠体内成瘤能力实验提示:CD133~+CD44~+(A组)细胞成瘤能力显著高于CD133~-CD44~-(B组)、CD133~-CD44~+(C组)和CD133~+CD44~-(D组)细胞(P<0.05);裸鼠瘤块病理检查证实均为腺癌,各脏器检查未发现转移:在接种CD133~+CD44~+(A组)细胞的瘤块组织中发现除了有CD133~+CD44~+细胞外,还有CD133~-CD44~-细胞.结论 肺腺癌A549细胞株中CD133~+CD44~+细胞在裸鼠体内的成瘤能力显著高于其他细胞.

The tumorigenic ability of human lung adenocarcinoma A549 cell CD133~+CD44~+ phenotype in nude mice

Objective To study the relationship between the expression of tumor stem cell marker CD133 and CD44 with the tumorigenic ability in human lung adenocarcinoma A549 cells. Methods In vitro individual cell culture was employed to observe the proliferating character of A549 cells. The expression of CD133 and CD44 in A549 cells was detected by using immunofluorescence and flow cytometry, and those cells were grouped according to the expression rate of CD133 and CD44. The cells were culured by using monoclonal method and subcutaneously injected into nude mice by different cell density. The tumorigenic ability of each group was observed. Results (1) The result of in vitro individual cell culture revealed that only 4.11% of cultured A549 cells underwent division, proliferation and formation of cell clones. (2) The positive expressions rate of CD133 was 19.0% in cells that can continue multiplicative division, and that was 2.5% in cells of conventional culture. The positive expressions rate of CD44 was 57.0% in cells that can continue muhiplicative division, and that was 34.0% in cells of conventional culture. The positive expres-sions rate of CD133 and CD44 was higher in cells that can continue multiplicative division than in cells of conventional culture (all P<0.01). (3) The tumorigenesis of CD133~+CD44~+ A549 cell was higher than CD133~-CD44~-, CD133~-CD44~+ and CD133~+CD44~- (P<0.05 ). Immunohistochemistry study discov-ered that transplantation tumor had expression of CD133 and CD44. Flow cytometry proved CD133~+CD44~+ A549 cells could differentiate into other phenotypes. Conclusion CD133~+CD44~+ A549 cells had ability of self-replication and could differentiate into other phenotypes. The tumorigenesis of CD133~+CD44~+ A549 cell was higher than other phenotypes.