ISSN:
1432-1335
Keywords:
Key words Costimulating molecule
;
B7-1(CD80)
;
B7-2(CD86)
;
Gastric carcinoma
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Costimulation of T cells via B7-1 and B7-2 molecules on a tumor has been shown to be important for eliciting cell-mediated antitumor immunity. We studied the surface expression of B7-1 and B7-2 in 24 cases of gastric carcinoma from the primary locus, 20 cases of metastatic carcinoma from malignant ascites, 20 cases of benign gastric mucosa and 7 gastric carcinoma cell lines by two-color flow cytometry with mAb CD80 and CD86. The B7-1 and B7-2 molecules were expressed by 6 cell lines, and 1 cell line showed the predominant expression of B7-2 but not B7-1. Almost all patients with primary gastric carcinoma and benign gastric mucosa showed high levels of expression of the B7-1 and B7-2, revealing approximately 40%–60% positive cells. However, the percentage of B7-1-positive cells of poorly differentiated primary carcinomas was significantly lower than that of well-differentiated carcinoma and normal mucosa (P〈0.01). Furthermore, all of the metastatic carcinoma cells revealed consistently very low or undetectable levels of expression of the B7-1 molecule, only 8% (mean) of cells being positive, despite showing higher levels of B7-2 expression. Thus, it seems likely that decreased or deleted expression of B7-1 correlates with the grade of tumor differentiation, tumor progression and metastasis. These results suggest that the B7-1 molecule on the gastric carcinoma bearing CD80+CD86+ is abrogated during tumor invasion and/or metastasis, and the tumor finally acquires the CD80−CD86+ phenotype. Consequently, inadequate B7-1 costimulation may contribute to the escape of tumors from destruction by the host's immune system.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004320050187
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