1. AXL knockout does not prevent dormancy.
AXL knockout does not prevent dormancy. A, Western blot showing AXL expression (left) in PC3 cells seeded at various densities (right, phase images; n = 1). Arrow represents 125 kDa. Scale bar, 500 μm. B, AXL expression by Western blot in PC3 cells (Par), a control knockout clone (Cntl KO), and two AXL knockout clones (Axl KO1 and Axl KO 2; n = 1). Arrow represents 125 kDa. C, BrdUrd incorporation over 24 hours in control and knockout cell lines ± GAS6. Results represent fold change between the incorporation readout on days 6 to 2 (n = 3). Error bars, mean ± SEM; P values calculated using the t test between Axl KO and Cntl KO, and within each cell line between treatments. D, Quantification of the number of large colonies (number of colonies in the top 65% of the range of colony size) in soft agar ± GAS6, relative to reference sample Par -GAS6 (n = 3). Error bars, mean ± SEM; P values calculated using multiple t-tests to assess differences due to treatment. E, Number and proliferation status of bone marrow DTCs detected in mice at 1 week after intracardiac injection. Each bar represents 1 mouse (n = 7 per group). F, Time in days to tumorigenesis after intracardiac injection. Tumorigenesis was defined as BLI signal over control PBS-injected mice (Cntl KO, n = 9; Axl KO, n = 12; each dot represents one mouse; mean ± SD). G, Duration of tumor growth of each group after intracardiac injection. Duration of growth was defined as the time between the onset of tumorigenesis and time to lethal tumor burden (Cntl KO, n = 9; Axl KO, n = 12; each dot represents one mouse; mean ± SD). H, Survival proportions for each group of mice over time (Cntl KO, n = 9 mice; Axl KO, n = 12 mice). P value calculated by the log-rank test. For relevant experiments, GAS6 was added at 100 ng/mL at the time of seeding. For mouse tumor growth P values were calculated by the t test. I, Number and proliferation status of bone marrow DTCs detected in mice at the time of death. Counting stopped after the first 500 BM-DTCs (n = 5 for each group).
Haley D. Axelrod et al. Mol Cancer Res 2019;17:
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