ASB2, MEIS2, and SRPX also showed significantly lower expression in high-risk Gleason score 8 tumors as compared to low or intermediate risk tumors, suggesting that these genes may be particularly useful as indicators of PCa progression.
Confocal microscopy using ([Alexa594]-(Cys0)-DRS-B2) shows that in sensitive human tumor cells (PC3), DRS-B2 seems to accumulate rapidly at the cytoplasmic membranes and enters the cytoplasm and the nucleus, while in less sensitive tumor cells (U87MG), DRS-B2 is found packed in vesicles at the cell membrane.
Because SRPX1, which is known as a tumor suppressor gene, reportedly induced apoptosis in tumor cells, we hypothesized that SRPX1 may play an important role in Aβ-induced apoptosis in CAA.
Our results indicate that down-regulation of drs mRNA is closely correlated with carcinomas which arise from adenomatous polyps in the course of the adenoma-carcinoma sequence, but that most carcinomas arising de novo are independent of the tumor suppressor function of the drs gene.
To investigate the function of the drs gene as a tumor suppressor in human cancer cells, we constructed recombinant amphotropic retrovirus containing the drs gene, introduced this virus into human cancer cell lines whose drs expression was downregulated and found that drs has the ability to suppress anchorage-independent growth of these cells without disturbing cell proliferation.