Fig. 6: AXL, CDK6, and FSCN1 mediate FRA1 pro-metastatic functions.

A Proliferation as measured by relative confluence of A375 cells with FRA1 silencing and concomitant AXL, CDK6, or FSCN1 overexpression. B Quantification of cell numbers of transwell invasion assays of A375 cells with FRA1 silencing and concomitant AXL, CDK6, or FSCN1 overexpression. C Proliferation as measured by relative confluence of 1205Lu cells expressing FRA1 with AXL, CDK6, or FSCN1 silenced. D Quantification of cell numbers of transwell invasion assays of 1205Lu cells expressing FRA1 with AXL, CDK6, or FSCN1 silenced. E FRA1 overexpressing 1205Lu cells with AXL, CDK6, or FSCN1 silenced were intravenously injected into NSG mice (n = 5). 7 days after inoculation, metastasis was detected by H&E staining. Representative images of micro-metastasis in lungs and quantification of the number and average size of micro-metastasis are shown. F, G Luciferase tagged 1205Lu cells were intravenously injected into NSG mice. AXL inhibitor Bemcentinib, CDK4/6 inhibitor G1T38, Fascin inhibitor NP-G2-044, and vehicle control were intraperitoneally (I.P.) administrated to mice (n = 5) at day 14, 16, 18, and 20 after cell inoculation (F). Metastasis was measured at day 20 by IVIS, and representative images and quantification of luminescence signals are shown (G). H 1205Lu cells were intravenously injected into NSG mice. Single or combination treatment of CDK4/6 inhibitor Abemaciclib and Fascin inhibitor NP-G2-044, or vehicle control were intraperitoneally (I.P.) administrated to mice (n = 5) once per day (Q.D.) until endpoint. I Quantification of metastasis burden in individual mice measured every 5 days by IVIS. J Overall survival curves of mice treated with the indicated inhibitors or vehicle control. Data are presented as mean ± SEM and analyzed with Student’s unpaired t test, * P < 0.05, ** P < 0.01, *** P < 0.001.