Fig. 2.

Template DNA is divided asymmetrically in several human lung cancer cell lines, immortalized bronchial epithelial cells, and primary lung tumors. (A) The frequency of asymmetric division of BrdU-labeled template DNA is shown by bar graphs for two normal immortalized HBET cell lines and six NSCLC cell lines. Data are reported as the mean ± SD from three independent experiments. At least 250 anaphases were scored in each experiment. *P < 0.01, one-way ANOVA between individual NSCLC cell lines and combined HBET cell lines. (B) Primary human lung cancer cells from two samples were BrdU-pulsed, chased, and treated with nocodazole. Shown is an example of asymmetric partitioning of BrdU-labeled DNA in a single late-telophase cell from sample 2. The number of asymmetric cell divisions is shown. (C) Primary human lung cancer cells from three samples were BrdU-pulsed, and colony assays were performed during the BrdU chase. Single cells were cocultured with unlabeled A549 cells. Colonies were visualized with CTR (red) and stained for BrdU (green). A representative colony demonstrating an asymmetric division of template DNA from sample 3 shows two BrdU⁺ cells (asterisks) and one BrdU⁻ cell (white arrow). The total number of colonies with both BrdU⁺ and BrdU⁻ cells is shown, 220 cells were scored and 17 cells were BrdU⁻. NOS, not otherwise specified; AC, adenocarcinoma; PE, Pleural effusion. (Scale bars, 5 μm in B; 20 μm in C.)