Increased expression of lung resistance-related protein in lower grade urothelial carcinoma of the renal pelvis and ureter.
BACKGROUND
Lung resistance-related protein (LRP), like multidrug resistance gene 1 (MDR1) and multidrug resistance-associated proteins (MRP), has been associated with intrinsic therapeutic resistance in various malignancies. To date, there has been no study on the expression of LRP in urothelial carcinomas of the renal pelvis and ureter. We investigated the protein and mRNA expression levels of LRP, MDR1 and MRP1 in this malignancy and the clinical significance of their expression was evaluated.


METHODS
Forty urothelial carcinomas of the renal pelvis and ureter and 31 normal upper urothelial samples were examined by immunohistochemistry and reverse transcription polymerase chain reaction to determine the protein and mRNA levels of the multidrug resistance-related genes, respectively.


RESULTS
The positive staining rates and mRNA levels of LRP were the highest among these multidrug resistance-related genes in both normal urothelium and carcinoma examinations. In contrast to the up-regulated expression of MDR1, the expression of LRP tended to be down-regulated in carcinomas. Moreover, the expression of LRP inversely correlated with tumor grades, but this correlation was not found for the other two genes. However, there was no correlation among the expression of the three genes observed.


CONCLUSIONS
Lung resistance-related protein was strongly expressed in urothelial carcinomas of the renal pelvis and ureter, particularly in well-differentiated carcinomas.
Kong
Chui-ze
CZ
Department of Urology, the First Affiliated Hospital of China Medical University, Shenyang, China.
Zeng
Yu
Y
Wu
Xiu-xian
XX
Li
Jia-qing
JQ
Zhu
Yu-yan
YY
Chen
Yan
Y
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000378:metabolism* / Q000473:pathology; D015536:Down-Regulation; D005260:Female; D015870:Gene Expression; D006801:Humans; D007680:Kidney Neoplasms / Q000378:metabolism* / Q000473:pathology; D007682:Kidney Pelvis; D008297:Male; D008875:Middle Aged; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics / Q000378:metabolism; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D015854:Up-Regulation; D014516:Ureteral Neoplasms / Q000378:metabolism* / Q000473:pathology; D019459:Urothelium; D020394:Vault Ribonucleoprotein Particles / Q000235:genetics / Q000378:metabolism*; D000099187:Major Vault Protein
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D020394:Vault Ribonucleoprotein Particles; D000099187:Major Vault Protein; C421109:multidrug resistance-associated protein 1