[The cytotoxicity and mechanism of CIK cells to breast cancer cells ZK-75-1].
OBJECTIVE
To study the cytotoxicity and mechanism of cytokine-induced killer (CIK) cells to breast cancer cell line ZK-75-1.


METHODS
The morphological changes of ZK-75-1 cells were observed by HE staining. The apoptosis of ZK-75-1 cell line was examined by TUNEL staining. The expression of P53, P16, C-myc, Bcl-2 and Bax was determined by immunocytochemical staining.


RESULTS
The result of HE staining revealed that CIK cells moved toward the target cells, forming typical rosette cells. Granule-like substances appeared in cytoplasm of tumor cells, but only granule-shape patch was found in some tumor cells while breast cancer cells as control grew well. TUNEL staining indicated that the cells in control group were not stained or dyed well-distributed light blue. As the cells in experiment group became smaller, mucleoluser or perinuclear was dyed deep blue. The apoptotic rate of ZK-75-1 cells cocultured with CIK cells was increased after 4-12 hours and was decreased after 12-24 hours, with a significant difference compared with control group (P<0.01). Immunocytochemical staining showed that the expression of p53, p16, C-myc and Bcl-2 proteins in CIK group declined but the expression of Bax protein increased with the passage of time, which was significantly different compared with control (P<0.01).


CONCLUSIONS
The mechanism of killing ZK-75-1 cells by CIK cells is closely related to the downregulation of the expression of P53, P16, c-myc and Bcl-2 proteins and to the upregulation of the expression of Bax protein. It also has close relation with the time of exposure to CIK cells.
Li
Xiang-dan
XD
Department of Pathology, Medical College of Yanbian University, Yanji 133000, China.
Sun
Shu
S
Song
Lian-lian
LL
Yang
Wan-shan
WS
Jin
Tie-feng
TF
D017209:Apoptosis; D045744:Cell Line, Tumor; D003469:Culture; D055612:Cytokine-Induced Killer Cells / Q000473:pathology*; D015536:Down-Regulation; D006801:Humans; D008297:Male; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism*
D019253:Proto-Oncogene Proteins c-bcl-2; D016271:Proto-Oncogene Proteins c-myc; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein