Expression of lung resistance-related protein in transitional cell carcinoma of bladder.
OBJECTIVE
To determine the role of lung resistance-related protein (LRP) in intrinsic multidrug-resistance (MDR) of bladder cancer.


METHODS
The study group consisted of 66 patients with newly diagnosed primary bladder cancer. No patient had been treated preoperatively with either radiotherapy or chemotherapy. Reverse transcriptase-polymerase chain reaction was performed to measure LRP, multidrug resistance-associated protein 1 (MDR1), and MRP1 mRNA expression. The expression of LRP, p53 proteins, and p63 proteins was examined by immunohistochemistry. We analyzed the correlation of LRP with the above indexes and the clinical pathologic parameters.


RESULTS
The expression rate of LRP mRNA (63.6%) was the greatest among the three MDR markers in primary bladder cancer without exposure to chemotherapy. The LRP mRNA level was significantly greater in normal bladder tissue than in transitional cell carcinoma bladder tissue (P <0.01) and in superficial cancer than in invasive cancer (P = 0.013). LRP mRNA expression showed no association with either MDR1 or MRP1, but close correlation with the LRP level (P = 0.001). LRP was associated with low-grade (P <0.01) and low-stage (P <0.05) cancer but had no association with tumor suppressor p53 or p63.


CONCLUSIONS
The grade and stage-related expression pattern of LRP indicates that it may be a predictive index for intrinsic MDR in early bladder cancer. Anticancer drugs out of the MDR spectrum of LRP may be more effective for patients with early bladder cancer.
Zhu
Yuyan
Y
Department of Urology, First Clinical College and First Affiliated Hospital, China Medical University, Shenyang, People's Republic of China.
Kong
Chuize
C
Zeng
Yu
Y
Sun
Zhixi
Z
Gao
Hong
H
D014408:Biomarkers, Tumor / Q000032:analysis / Q000378:metabolism*; D002295:Carcinoma, Transitional Cell / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D018432:Drug Resistance, Multiple / Q000235:genetics*; D019008:Drug Resistance, Neoplasm; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D009363:Neoplasm Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D001743:Urinary Bladder / Q000737:chemistry / Q000378:metabolism*; D001749:Urinary Bladder Neoplasms / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D020394:Vault Ribonucleoprotein Particles / Q000235:genetics / Q000378:metabolism*; D000099187:Major Vault Protein
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D020394:Vault Ribonucleoprotein Particles; D000099187:Major Vault Protein