[Studies on multidrug resistance associated protein in retinoblastoma].
OBJECTIVE
To detect the expression of P-glycoprotein (P-gp), lung resistance associated protein (LRP) and multidrug resistance associated protein (MRP) in retinoblastoma (Rb), to analyze the relationship between the expression of multidrug resistant (MDR) markers with clinic-pathological factors, the correlations among these three markers, and to study the possible mechanism of multidrug resistance in Rb.


METHODS
It was an experimental study. Seventy-five cases of Rb were studied with immunohistochemical methods using antibodies against P-gp, LRP and MRP. The relationship between their expression and the clinicopathological features of Rb, and the relationship between the expression of these three markers were investigated.


RESULTS
The positive expression rates of P-gp, LRP and MRP were 64.0%, 25.3%, 36.0% in Rb, respectively. The co-expression rates of P-gp and LRP, P-gp and MRP, LRP and MRP were 18.7%, 32.0%, 20.0%, respectively. All tested proteins showed significant correlation to the differentiation of the tumor (P = 0.006, 0.000, 0.000, respectively), but no correlation was found between the expression of these markers and the age or sex of the patients. Significant positive correlations were observed between P-gp and MRP expression (P = 0.001), and between LRP and MRP expression (P = 0.000).


CONCLUSIONS
The intrinsic multidrug resistance of Rb involves the combined effects of P-gp, LRP and MRP.
Li
Bin
B
Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China. libin43_99@Yahoo.com
Gao
Rui
R
Zhang
Hao
H
Li
Liao-qing
LQ
Gao
Fei
F
Ren
Ruo-jin
RJ
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D002675:Child, Preschool; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D008297:Male; D009363:Neoplasm Proteins / Q000378:metabolism*; D019572:Retinal Neoplasms / Q000378:metabolism* / Q000473:pathology; D012175:Retinoblastoma / Q000378:metabolism* / Q000473:pathology
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D009363:Neoplasm Proteins