The prostate stem cell antigen represents a novel glioma-associated antigen

Abstract

Abstract. gliomas of WHo grades III-IV are malignant brain tumors mostly resistant to conventional therapies. therefore, novel strategies for the treatment of gliomas are warranted. Although immunotherapy is gaining increased attention for the treatment of malignant gliomas and in particular of glioblastoma multiforme (gBM), this approach requires the identification of appropriate antigens. Our aim was to investigate the expression of the prostate stem cell antigen (pscA), a highly n-glycosylated phosphatidylinositol (gpI)-anchored cell surface protein, in gliomas of different WHo grades in order to evaluate its potential as a diagnostic marker and as a target for immunotherapy. tumor specimens and controls were assessed by quantitative rt-pcr, Western blotting and immunohistochemistry. the samples investigated in the study consisted of 210 human glial tumors, among which 31 were oligodendrogliomas, 9 ependymomas and 170 were astrocytomas (including 134 glioblastomas). pscA was absent in normal brain tissue, but was detected in WHo grade III-IV gliomas. Weak pscA protein expression was also recognized in some WHo grade I and WHo grade II tumors. the difference between WHo grade I-II tumors and WHo grade III-IV tumors was statistically significant (p<0.001). our results suggest that increased pscA expression levels are linked to gliomas of WHo grades III and IV, and may represent a suitable additional target for immunotherapy of gliomas.

Lack of association between the rs2294008 polymorphism in the prostate stem cell antigen gene and colorectal neoplasia: a case-control and immunohistochemical study

“…Overexpression of PSCA, either at mRNA or protein level, has also been described in several other human solid cancers including those of bladder, endometrium, kidney, pancreas, ovary, central nervous system, and lung [4-10]. Alterations in PSCA expression have been implicated in upper gastrointestinal carcinogenesis, with loss of PSCA expression reported in gastric, oesophageal, and gallbladder cancer, and intestinal metaplasia, a gastric cancer precursor lesion [11-13].…”

Prostate stem cell antigen gene is expressed in islets of pancreas

“…In contrast, down-regulation of the gene was reported in gastric and gallbladder cancers, where it may act as a tumor suppressor [4, 5]. Moreover, there is another type of expression pattern: no expression in normal tissues but expressed in malignant counterparts, which is seen in pancreatic cancer [6], non-small cell lung cancer [7] and glioma [8]. It was reported that PSCA expression was not observed in the normal pancreas by northern blotting or immunohistochemistry and that its transcript could be a practical biomarker in detecting pancreatic cancer [6].…”

Characterization and function of human Ly-6/uPAR molecules

“…Previous studies have reported that PSCA expression is upregulated in prostate cancer, pancreatic adenocarcinoma, transitional cell carcinoma, clear cell renal cell carcinoma, diffuse-type gastric cancer, endometrial adenocarcinoma, non small cell lung cancer, cervical squamous cell carcinoma, invasive micropapillary carcinoma, and glioma (46-55). In contrast, PSCA is downregulated in esophageal, gastric, stomach tumors, HNSCC, and gallbladder carcinogenesis (27,56,57).…”