Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Y-box-binding protein, YB-1, is a member of the DNA-binding protein family. It binds to the Y-box, an inverted CCAAT box, in the promoter region of the human multidrug resistance 1 gene, which encodes P-glycoprotein (P-gp). Nuclear localization of YB-1 protein has been reported to be associated with the intrinsic expression of P-gp in human breast cancer. We studied the immunohistochemical expression of YB-1 protein in 69 untreated biopsy specimens of conventional osteosarcomas and compared it with the expression of P-gp. Furthermore, cell proliferation, as determined by the MIB-1-labeling index (MIB-1-LI), was measured by immunohistochemistry. In all 69 untreated osteosarcomas, YB-1 protein was expressed in the cytoplasm. In 32 of 69 (46%) cases, YB-1 was also localized in the nucleus. The expression of P-gp was evident in 23 of these 32 cases, and there was a significant correlation between the nuclear expression of YB-1 and P-gp expression (P < 0.0001). Chondroblastic osteosarcoma expressed YB-1 in the nucleus more frequently (eight of nine cases) than did other types of osteosarcoma, whereas P-gp was also frequently expressed in chondroblastic subtype. There was no correlation between the nuclear expression of YB-1 and histological grade. The MIB-1-LI was significantly higher in cases showing the nuclear expression of YB-1 (MIB-1-LI averaged 22.56 in cases with only cytoplasmic expression of YB-1 but averaged 28.20 in cases with cytoplasmic and nuclear expression of YB-1; P = 0.0477). In human osteosarcoma, nuclear localization of YB-1 protein was associated with the expression of P-gp, suggesting that YB-1 could be a prognostic marker for multidrug resistance in osteosarcoma.
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PMID:Nuclear expression of YB-1 protein correlates with P-glycoprotein expression in human osteosarcoma. 974 49

Nuclear expression of the Y-box-binding protein (YB-1) has been reported to correlate with the expression of P-glycoprotein in breast cancer and osteosarcoma. Overexpression of the ATP-binding cassette (ABC) superfamily, such as P-glycoprotein/multi-drug resistance (MDR) 1 and MDR-associated protein (MRP) 1, 2 and 3, has been reported in various malignant neoplasms. Fifty-four surgically resected synovial sarcomas were examined immunohistochemically for nuclear expression of YB-1 and intrinsic expression of P-glycoprotein, MRP1, MRP2, and topoisomerase II alpha, and the findings were compared with clinicopathological parameters, proliferative activities as evaluated by MIB-1 labelling index (LI), and the patients' prognoses. In addition, MDR1, MRP1, MRP2, and MRP3 mRNA levels were assessed using a quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method in 22 concordant frozen specimens from these cases and the findings were compared with six control skeletal muscle tissues. Independent prognostic factors were investigated using the Cox proportional hazards regression model. Nuclear expression of YB-1 protein correlated with P-glycoprotein expression (p = 0.0126). Moreover, cases with nuclear expression of YB-1 correlated with poor survival (p = 0.0495) and showed a high topoisomerase II alpha labelling index (topo II alpha LI) (p = 0.0056) and a high MIB-1 LI (p = 0.01). Multivariate Cox analysis showed that only the nuclear expression of YB-1 (p = 0.0136) and high American Joint Committee on Cancer (AJCC) stage (ie stage III or IV) (p < 0.0001) were independent factors for poor prognosis, while the expression of the YB-1 responsive gene products examined was not. These results indicate that the nuclear expression of YB-1 protein is associated with P-glycoprotein expression and proliferative activity as shown by the topo II alpha LI and the MIB-1 LI, and that expression of this protein is an important independent prognostic factor in synovial sarcoma.
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PMID:Nuclear expression of Y-box-binding protein-1 correlates with P-glycoprotein and topoisomerase II alpha expression, and with poor prognosis in synovial sarcoma. 1253 39