Phenotypic and functional heterogeneity of McNeuA and Met-1 breast cancer cells.

<p><b>(A)</b> Concentration of murine OPN (mOPN; ng/ml per 10⁶ cells) in 24-hr conditioned medium of McNeuA and Met-1 murine mammary carcinoma cells represented as mean ± SD. There was no detectable mOPN in the control cell-free medium (DMEM) (2 technical replicates per group). <b>(B)</b> Incidence of tumor formation following injection of indicated numbers of McNeuA or Met-1 cells into cohorts of FVB mice. <b>(C)</b> Plasma mOPN concentration (ng/ml) in indicated cohorts of mice at experimental end points of 84 days (McNeuA) and 30 days (Met-1). For McNeuA tumor-bearing mice, blue data points represent 10,000 cells injected, red data points represent 100,000 cells injected; n = 6–7 for McNeuA cohorts; n = 5–8 for Met-1 cohorts. Error bars represent SD; statistical significance evaluated using unpaired, two-tailed Student’s t-test. <b>(D)</b> Representative images of immunohistochemical staining for murine E-cadherin (red) on recovered McNeuA and Met-1 tumors. Cell nuclei were counterstained with hematoxylin (blue). Scale bars = 100 μm. (B-D) representative of 3 independent experiments per cell line. <b>(E)</b> Average radiance (log₁₀) per mouse (n = 5) as measured by bioluminescence imaging over 21-day time course following intravenous injection of 10⁶ Met-1 tumor cells into FVB mice (left graph). Fold-change (log₂) in pulmonary metastatic burden per mouse (right graph). Representative of 2 independent experiments. <b>(F)</b> Response of orthotopic Met-1 GFP/Luc tumors to single dose combination doxorubicin (5 mg/kg), paclitaxel (10 mg/kg) and cyclophosphamide (120 mg/kg) (AC-T), n = 5–8 tumors/group. Ordinate represents time (days) following treatment. Error bars represent SEM; two-way ANOVA Sidak’s multiple comparisons test; **p<0.01. Representative of 3 independent experiments. <b>(G)</b> Growth kinetics of individual orthotopic Met-1 Luc/GFP tumors in mice injected with 2.5 x 10⁵ tumor cells at the experiment initiation, subsequently receiving 4 biweekly AC-T doses (red arrows). Numbers and colors represent individual mice.