Progression of Luminal Breast Tumors Is Promoted by Ménage à Trois between the Inflammatory Cytokine TNFα and the Hormonal and Growth-Supporting Arms of the Tumor Microenvironment

Figure 2

Combined stimulation of breast tumor cells by TNFα + Estrogen + EGF induces the localization of FAK and paxillin in cell protrusions and formation of intertumor connecting tubes. Breast tumor cells were stimulated by TNFα + Estrogen + EGF (concentrations as in Figure 1) for three days. Non-stimulated: cells grown with the diluents of the above factors. (A) The expression of FAK. (A1) Non-stimulated cells. ((A2a), (A2b)) Cells stimulated by TNFα + Estrogen + EGF, where part (A2b) demonstrates the formation of tubes connecting between different tumor cells. FAK expression was detected by specific Abs (red), actin filaments by phalloidin staining (green), and cell nuclei by DAPI staining (blue). In all panels, the results are from a representative experiment of 𝑛≥3. (B) The expression of paxillin. (B1) Non-stimulated cells. ((B2a), (B2b)) Cells stimulated by TNFα + Estrogen + EGF, where part (B2b) demonstrates the formation of tubes connecting between different tumor cells. Paxillin expression was detected by specific Abs (purple), actin filaments by phalloidin staining (green), and cell nuclei by DAPI staining (blue). In all panels, the results are from a representative experiment of 𝑛≥3.