Quantitation of biological tumor markers (p53, c-myc, Ki-67 and DNA ploidy) by multiparameter flow cytometry in non-small-cell lung cancer.
Fifteen primary non-small-cell lung carcinomas (8 adenocarcinomas and 7 squamous-cell carcinomas) were analyzed by multiparameter flow cytometry for their expression of p53 and c-myc proteins. In addition, the fraction of cells staining with the proliferation-associated antibody Ki-67 and DNA ploidy was determined. These 4 biological markers were analyzed in parallel samples from a single-cell suspension made from fresh, frozen biopsies. Thus, the internal relationship between these markers within each tumor-cell population was established. Three different anti-p53 antibodies were used: PAb 421, PAb 1801 and PAb 240. All 15 tumors were p53-positive with the antibodies PAb 1801 and PAb 240, whereas only 9 were positive as judged by the antibody PAb 421. This indicates that the choice of p53 antibody is not irrelevant. Ten tumors were c-myc-positive; 7 of these were adenocarcinomas. The c-myc-positive tumors had a significantly higher level of p53 expression, judged by PAb 1801 and PAb 240, than c-myc-negative tumors. For PAb 421, there was no difference. We did not find any correlation between Ki-67 staining and expression of p53 and c-myc proteins, either with DNA ploidy, S-phase fraction or histological type. Our study indicates that there might be an association between accumulation of p53 protein and c-myc over-expression in non-small-cell lung cancer, and that this in particular might apply to adenocarcinomas. Furthermore, we show that multiparameter flow cytometry is a powerful tool in the study of the relationship between different markers in a cell population.
Mørkve
O
O
Department of Thoracic Medicine, Gade Institute, Norway.
Halvorsen
O J
OJ
Stangeland
L
L
Gulsvik
A
A
Laerum
O D
OD
D014408:Biomarkers, Tumor / Q000032:analysis*; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics*; D004273:DNA, Neoplasm / Q000235:genetics*; D005434:Flow Cytometry / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D019394:Ki-67 Antigen; D007834:Lasers; D008175:Lung Neoplasms / Q000235:genetics*; D009363:Neoplasm Proteins / Q000032:analysis; D009687:Nuclear Proteins / Q000032:analysis; D011003:Ploidies; D016271:Proto-Oncogene Proteins c-myc / Q000032:analysis; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D016271:Proto-Oncogene Proteins c-myc; D016159:Tumor Suppressor Protein p53