RT Journal Article SR Electronic T1 Down-regulation of Immune-related Genes by PSCA in Gallbladder Cancer Cells Implanted into Mice JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 2619 OP 2625 VO 35 IS 5 A1 NORIHISA SAEKI A1 HIROE ONO A1 HIROMI SAKAMOTO A1 TERUHIKO YOSHIDA YR 2015 UL http://ar.iiarjournals.org/content/35/5/2619.abstract AB Background/Aim: In previous work, we found that prostate stem cell antigen (PSCA) gene, encoding a glycosylphosphatidylinositol-anchored protein, is a presumable tumor suppressor in gastric cancer and gallbladder cancer (GBC). The introduction of PSCA cDNA into GBC cell lines significantly suppressed tumorigenecity of cells in mice. The PSCA protein is thought to be involved in some form of intracellular signaling that remains to be elucidated. Materials and Methods: Using microarrays, we conducted gene-expression profiling on tumors generated by a GBC cell line TGBC-1TKB, with and without expression of PSCA, which was implanted into mice. Genes whose expression was down-regulated by PSCA were selected, and their down-regulation was confirmed by real-time PCR. Results: We identified several immune-related genes down-regulated by PSCA, including interleukin 8 (IL8), IL1 receptor antagonist (IL1RN) and S100 calcium-binding proteins A8 (S100A8) and A9 (S100A9). Conclusion: PSCA signaling may suppress tumor growth in vivo by modulating immunological characteristics of GBC cells.