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Akt1 mediates prostate cancer cell microinvasion and chemotaxis to metastatic stimuli via integrin β₃ affinity modulation.

ABSTRACT:

Background

Activation of Akt and increased expression of integrin β(3) are the two most important changes that have been linked to the attainment of metastatic potential by prostate cancer cells. However, a direct link between Akt activity and inside-out activation of integrin β(3) in mediating prostate cancer cell metastatic properties is not established.

Methods

Using functional and biochemical approaches, we examined the role of Akt1 in the affinity modulation of integrin β(3) in prostate cancer cells.

Results

Although expression of murine TRAMP and human PC3 cells with constitutively active Akt1 (CA-Akt1) enhanced their affinity for integrin α(v)β(3) specific ligands and motility on various extracellular matrix proteins, the reverse was observed with the expression of dominant-negative Akt1 (DN-Akt1). Although enhanced motility and transendothelial migration of CA-Akt1-expressing cells were blunted by co-expression with DN-integrin β(3) or upon pre-treatment with integrin β(3)-blocking antibodies (LM 609), impaired motility and transendothelial migration of DN-Akt1-expressing cells were rescued by pre-treatment of prostate cancer cells with integrin β(3)-activating antibodies, AP7.4.

Conclusion

Our data is the first to demonstrate a link between Akt1 activity and affinity modulation of integrin β(3) in the regulation of prostate cancer cell motility, transendothelial migration and chemotaxis to metastatic stimuli.

SUBMITTER: Goc A

PROVIDER: S-EPMC3419951 | biostudies-literature |

REPOSITORIES: biostudies-literature

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