Identification and validation of tumor biomarkers for urogenital cancer using proteomic analysis of cell culture supernatant

新的蛋白质组学方法鉴定可能参与膀胱癌肿瘤侵袭的蛋白质。我们通过比较膀胱癌低侵袭性细胞系和高侵袭性细胞系的分泌蛋白谱来寻找候选蛋白。从细胞培养上清中分离的蛋白采用散弹枪蛋白组学进行鉴定。我们发现CXCL1调节膀胱癌细胞的侵袭能力。该趋化因子可能是侵袭性膀胱癌尿液生物标志物的潜在候选物，也可能是预防肿瘤侵袭的治疗靶点。新的蛋白质组学方法鉴定和验证肾细胞癌的新型血清肿瘤标志物。我们建立了一种利用无血清培养基分析细胞培养上清分泌蛋白的新方法，并比较了转染野生型pVHL质粒和空表达质粒稳定转染786-O RCC （VHL-/-）亚克隆的蛋白质组学。通过这种方法，我们鉴定了三种不同的VHL调节分泌蛋白（PAI-1，IGFBP-3和clusterin）。与正常对照相比，ccRCC患者血清中IGFBP-3明显升高。另一方面，我们对4例散发性透明细胞RCC患者行肾切除术前后的“血清蛋白质组学”进行了初步分析。共有6个蛋白被鉴定为候选标记，这些蛋白在术前检测到，但在术后消失。其中2个基因在肿瘤标本中表达较正常邻近正常组织低。现在我们对这些候选蛋白进行进一步的验证。

New proteomic approach for the identification of proteins that are potentially involved in the tumor invasion of bladder cancer.We searched for the candidate proteins by comparing the profiles of secreted proteins among the poorly invasive human bladder carcinoma cell line and the highly invasive cell line. The proteins isolated from cell culture supernatants were identified by shotgun proteomics. We found that CXCL1 modulates the invasive abilities of bladder cancer cells and. this chemokine maybe a potential candidate of urinary biomarker for invasive bladder cancer and a possible therapeutic target for preventing tumor invasion.New proteomic approach for the identification and validation of novel serum tumor makers for renal cell carcinoma.We established a new method fir analyzing the secreted proteins in cell culture supernatants by using serum-free media and compared the proteome among 786-O RCC (VHL-/-) subclones stably transfected with either a plasmid encoding wild-type pVHL or an empty expression plasmid. By using this method, we identified three different VHL regulated secreted proteins (PAI-1,IGFBP-3 and clusterin). IGFBP-3 is elevated significantly in the serum from patients with ccRCC comparing with that from normal controls. On the other hand, we had done the preliminary analysis of "serum proteome" of 4 patients with sporadic clear cell RCC before and after the nephrectomy by using novel multidimensional shotgun proteomics. A total of 6 proteins were identified as candidate markers that were detected before the operation, but disappeared after the procedure. Two of them were biddy expressed in tumor specimens comparing with that of normal adjacent normal tissue. Now we perform further validation of these candidate proteins.