Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P41181 (collecting duct)
 5,183 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Renal epithelial cancers represent a heterogeneous group of neoplasms arising from the malignant transformation of presumed diverse cell lineages. We recently demonstrated that tumor-specific up-regulation of human leukocyte antigen (HLA)-G, a nonclassical HLA class Ib molecule that might be involved in immune evasion by tumor cells, frequently occurs in conventional (clear cell) renal carcinoma. We here examined whether HLA-G activation is a common process affecting all types of renal epithelial tumors. We analyzed a series of 38 paraffin-embedded tumors including clear cell, papillary, chromophobe, collecting duct carcinoma, and oncocytoma. Seven of 12 (58%) clear cell tumors were positive by immunohistochemistry, whereas all of the other subtypes of renal carcinoma were negative for HLA-G expression. Developing or adult normal renal tissue were devoid of HLA-G expression. We also observed that ectopic expression of HLA class II antigens occurs more frequently in clear cell renal carcinoma than in other subtypes of renal tumors. Moreover, in contrast to the common observation of a down-regulation of major histocompatibility complex class Ia antigens reported in various tumors, the concomitant study of the same biopsies for classical HLA class Ia antigen expression revealed a general increase of HLA class Ia expression, regardless of histological subtypes. These results provide evidence for the heterogeneity of major histocompatibility complex expression patterns in renal carcinoma and support the hypothesis that specific mechanisms underlying the malignant transformation into clear cell renal carcinoma up-regulate expression of HLA-G and to a lesser extent HLA class II molecule expression. Considering the immunotolerant role of HLA-G toward the immune response, these mechanisms may thus provide renal cell carcinoma tumor cells with additional means to escape immune surveillance.
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PMID:Altered pattern of major histocompatibility complex expression in renal carcinoma: tumor-specific expression of the nonclassical human leukocyte antigen-G molecule is restricted to clear cell carcinoma while up-regulation of other major histocompatibility complex antigens is primarily distributed in all subtypes of renal carcinoma. 1254 8

Previous studies showed that human leukocyte antigen (HLA)-G is specifically upregulated in renal cell carcinoma (RCC). However, a larger cohort of RCC patients are necessary to obtain more information. In this study, 109 RCC primary lesions (clear cell, n = 95; chromophobe, n = 4; papillary, n = 4; collecting duct, n = 6) and corresponding adjacent tumor-negative renal tissues (n = 34) were analyzed for the HLA-G expression by immunohistochemistry (IHC). Meanwhile, plasma soluble HLA-G (sHLA-G) from 16 RCC patients and 144 sex- and age-matched normal individuals was detected by enzyme-linked immunosorbent assay. Correlations between lesion HLA-G expression and various clinical parameters were evaluated. Receiver-operating characteristic (ROC) curve analysis was used to determine the feasibility of HLA-G protein staining and sHLA-G as a diagnosis marker for RCC. IHC data showed that HLA-G was observed in 49.5% of clear cell, 50% of either chromophobe or collecting duct RCC lesions but undetectable in papillary RCC and tumor-negative renal tissues. This finding was consistent with the western blot results. sHLA-G was pronouncedly increased in RCC patients when compared with normal controls (median: 39.5 vs 19.2 U/ml, P = 0.002). However, no correlation was observed between HLA-G expression and various clinical parameters. We found that the area under ROC curve for HLA-G expression and sHLA-G was 0.739 [95% confidence interval (95% CI): 0.659-0.816, P = 0.000] and 0.733 (95% CI: 0.619-0.847, P = 0.002), respectively. Our findings indicated that, except the papillary RCC, other types of RCC could express HLA-G. Furthermore, both lesion HLA-G expression and plasma sHLA-G level might be a useful preoperative biomarker for diagnosis.
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PMID:Characterization of HLA-G expression in renal cell carcinoma. 1953 Nov 1