Prosurvival function of the nuclear transport factor Cellular Apoptosis Susceptibility (CAS) in hepatocarcinogenesis

There is emerging evidence that malignant progression can involve deregulated expression and function of nuclear transport factors. As an important member of the nucleo-cytoplasmic transport machinery the karyopherin Cellular Apoptosis Susceptibility (CAS) re-shuttles importin-α from the nucleus to the cytoplasm. As indicated by its name CAS was reported to have proapoptotic functions under stressed conditions. Surprisingly, we found that under unstressed conditions CAS knockdown in hepatoma cell lines leads to an increase of apoptosis and to attenuated cell growth, proliferation, migration, and invasion. Consis…