Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0403608 (ureter)
 9,655 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Classic multidrug resistance is mediated by a P-glycoprotein. Using monoclonal antibody C219 (MAb C219) in an immunohistochemical study, we found high levels of putative Golgi P-glycoprotein in normal columnar and transitional epithelium in subpopulations of patients with specific blood types. For example, Golgi staining was present in blood type A patients in 46% of normal colon samples (N = 21) and 88% of normal ureter samples (N = 17). In comparison, Golgi staining was present in blood group O patients in only 6% of normal colon samples (N = 34) and in 0% of normal ureter samples (N = 19). The association of MAb C219 Golgi staining with blood type A and lack of Golgi staining with blood type O was statistically significant in normal colon (P = .001) and normal ureter (P less than .0001). Inappropriate hyperexpression of P-glycoprotein was frequently found in colon carcinomas. Additional evidence that Golgi MAb C219 reactivity represents P-glycoprotein is presented. This includes (1) immunostaining of Golgi with two anti-P-glycoprotein MAbs, C219 and JSB-1, and (2) experiments in which Mab C219 Golgi reactivity was blocked by preincubation of MAb C219 with a specific P-glycoprotein epitope-containing peptide. The high degree of association of Golgi P-glycoprotein with blood type A may suggest a role for P-glycoprotein in processing or trafficking of specific blood group antigens.
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PMID:ABO blood type predicts the cytolocalization of anti-P-glycoprotein monoclonal antibody reactivity in human colon and ureter. 197 52

We assessed the expression of P-glycoprotein, the product of the multidrug resistance gene, in 107 specimens from patients with transitional cell carcinoma of the upper urinary tract, using an immunohistochemical method with a polyclonal antibody. P-glycoprotein was expressed in 28 of 107 (26%) specimens. While P-glycoprotein expression was not related to the grade or stage of these tumors, the incidence of P-glycoprotein in specimens with tumors which coexisted in renal pelvic and ureter is significantly higher than those with either renal pelvic or ureter tumor alone. In the patients with advanced upper urinary tract tumor who had adjuvant chemotherapy including at least one P-glycoprotein-transported drug (mdr regimen), overall survival of patients with P-glycoprotein-positive tumor was significantly shorter than that of patients with negative tumor. This pilot study demonstrates that P-glycoprotein can be expressed in one fourth of transitional cell carcinomas of the upper urinary tract and that P-glycoprotein expression serves as a prognostic indicator in patients with these tumors who are treated with mdr regimens.
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PMID:Expression of multidrug resistance gene product (P-glycoprotein) in transitional cell carcinomas of the upper urinary tract. 771 32

The intrinsic or acquired resistance of urothelial cancer to chemotherapy is one major obstacle to successful treatment. Generally, the expression level of P-glycoprotein in urothelial cancer is low, so we accordingly investigated the expression of multidrug resistance-associated protein (MRP). We examined the expression of MRP mRNA by means of slot-blotting samples of 11 renal pelvic and/or ureteral tumors, 33 bladder tumors, one lung metastasis from a ureter tumor, 7 non-cancerous urothelia from patients with transitional-cell carcinoma (TCC) and one urothelium from a patient with renal-cell carcinoma (RCC). We also estimated, by Southern blotting, whether or not the MRP gene was amplified in clinical specimens that overexpressed MRP mRNA. MRP was detected immunohistochemically using a polyclonal antibody against MRP. In all, 5 of 11 renal pelvic and/or ureter tumors (45.5%), 17 of 33 bladder tumors (51.5%) and 4 of 7 non-cancerous urothelia of TCC patients (57.1%) expressed more than 2-fold the MRP mRNA levels of drug-sensitive human KB cells. There was no significant difference in the MRP mRNA level between primary and recurrent tumors. Low-grade urothelial carcinomas (G1 and G2 TCCs) expressed significantly higher levels of MRP mRNA than the high-grade G3 TCC. The MRP gene was not amplified in urothelial carcinomas, irrespective of their expression levels of MRP mRNA. Immunohistochemically, MRP was located mainly on the plasma membrane, but also detected on the cytoplasm of cancer cells. MRP may be one mechanism responsible for intrinsic drug resistance in low-grade urothelial cancer.
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PMID:Expression of the multidrug resistance-associated protein (MRP) gene in urothelial carcinomas. 898 Feb 53