[WAF1/CIP1/p21 gene in wild type p53 and mutant p53 human breast cancer cell lines in relation to its cytobiological features].
OBJECTIVE
To study the WAF1/CIP1 gene DNA status, mRNA and protein expressions in human breast cancer cell line and its significance.


METHODS
Using cell culture, molecular biological techniques such as Southern blot, Northern blot and immunocytochemical methods, the WAF1/CIP1 gene DNA status, mRNA and protein expression levels in MCF-7 expressing wild type p53(wtp53) and MDA-MB-231 expressing mutant p53 (mtp53) human breast cancer cell lines were detected respectively. The p53 and mdm-2 protein expression levels and cytobiological features of the 2 cell lines were compared and correlated to their WAF1/CIP1 gene expression levels.


RESULTS
(1) There was no difference in WAF1/CIP1 gene DNA status in the two breast cancer cell lines. Neither of them showed gene amplificatian or deletion. However, the WAF1/CIP1 mRNA and p21WAF1/CIP1 protein expression levels of MCF-7 cells were higer than those of MDA-MB-231 cells (P < 0.05). (2) The character and cellular distribution of p53 protein in the two cell lines were clearly different. The expression level of mdm-2 proteion was significantly higher in MCE-7 than in MDA-MB-231 cells (P < 0.05). (3) Compered to the other breast cancer cell line, MCF-7 cells were better differentiated, grew more slowly and adhered more closely with each other.


CONCLUSIONS
The WAF1/CIP1 gene expression at mRNA and protein levels is associated with p53 phenotype and some cytobiological features of human breast cancer.
Department of Surgery, Cancer Hospital, Shanghai Medical University.
M
M
Jiang
Z
Z
Shao
J
J
Wu
D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D016158:Genes, p53; D006801:Humans; D009154:Mutation; D009363:Neoplasm Proteins / Q000096:biosynthesis; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D051736:Proto-Oncogene Proteins c-mdm2; D012333:RNA, Messenger / Q000235:genetics; D014407:Tumor Cells, Cultured
C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2