Figure 4.

Roles of integrin α2β1 in multiple types of cancer. Top panel: Melanoma cells that produce high levels of VEGF and PLGF can stimulate endothelial cells of α2-null mice, which have increased VEGFR1 to stimulate angiogenesis.⁴¹ Right panel: Ovarian cancer cells that express high levels of EGFR can block integrin α2β1 signaling by increasing its internalization.⁸⁶ Left panel: In prostate cancer, α2β1 promotes invasion by RhoC GTPase expression.⁶⁶ Bottom panel: Absence of α2β1 in the stroma of host mice promotes spontaneous metastasis of transgenic c-neu oncogene-initiated breast cancer.⁷²