Abstract
Purpose::
To explore whether arginine deiminase (ADI), whose anti-tumor activity depends on argininosuccinate synthetase (ASS) activity, could be a potential anti-cancer agent of retinoblastoma
Methods::
In tumors of 20 retinoblastoma patients, argininosuccinate synthetase (ASS) expression was evaluated by immunohistochemistry. In retinoblastoma cell lines of Y79 and SNUOT-Rb1, ASS expression was checked by western blotting and RT-PCR. Anti-tumor activity of ADI was evaluated by cell count, LDH, and FACS. To evaluate ASS activity of these cell lines, anti-tumor activity of ADI in arginine+/citruline- condition was compared to that in arginine-/citruline+/ADI- condition.
Results::
In all retinoblastoma tumors and both retinoblastoma cell lines, ASS was highly detected. However, ADI significantly inhibited cell growth, induced cell death and apoptosis of both retinoblastoma cell lines. The anti-tumor activity of ADI in arginine+/citruline- condition was just same as that in arginine-/citruline+/ADI- condition.
Conclusions::
Our data suggests that ASS activity might be disturbed in some retinoblastoma and in these cases, ADI could be a potential anti-cancer agent of retinoblastoma. We are under the investigation for the mechanism of ASS activity loss in retinoblastoma.
Keywords: retinoblastoma • tumors • pathology: experimental