[Expression of ATP-binding cassette transporter ABCG2 in gastric carcinoma and its significance].

OBJECTIVE

To investigate the expression of ATP-binding cassette transporter (ABCG2) in gastric carcinoma and its clinical significance.

METHODS

Expression of ABCG2 protein was examined by immunohistochemical technique in specimens from 45 gastric carcinoma tissues and 30 surrounding normal tissues. The expression of ABCG2 mRNA was measured by RT-PCR and real-time quantitative PCR in specimens from 30 gastric carcinoma tissues and 30 surrounding normal gastric mucosa respectively.

RESULTS

ABCG2 protein expression was observed in 28 of 45 (62.2%) cases by immunohistochemical analysis, while in 2 of 30 (6.7%) normal tissues (P< 0.05). In ABCG2-positive tumors, adjacent non-neoplastic tissue was similarly analyzed and revealed that ABCG2 was up-regulated in gastric carcinoma. The positive rates of ABCG2 expression in poorly differentiated and/or undifferentiated carcinoma were significantly higher than those in well and/or moderately-differentiated carcinoma (P< 0.05). The mRNA expression of ABCG2 was significantly higher in gastric carcinoma tissue than that in normal gastric mucosa (P< 0.05).

CONCLUSIONS

ABCG2 expression is up-regulated in gastric carcinoma. ABCG2 may be an important factor in the research of gastric cancer stem cell.