Background Wilms' tumor (nephroblastoma) is a cancer of the kidneys that occurs typically in children and rarely in adults. Early diagnosis is very important for the treatment and prognosis of the disease. The aim of our study was to discover and identify potential non-invasive and convenient biomarkers for the diagnosis of Wilms' tumor. Methods Nude mice were used to construct a Wilms' tumor model by injecting nephroblastoma cells into their bilateral abdomen. We collected 94 serum samples from mice consisting of 45 samples with Wilms' tumor and 49 controls. The serum proteomic profiles of the samples were analyzed via surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. The candidate biomarkers were purified by high-performance liquid chromatography, identified by liquid chromatography-mass spectrometry, and validated using ProteinChip immunoassays. Results We finally retrieved two differential proteins (mlz 4509.2; 6207.9), which were identified as apolipoprotein A-II and polyubiquitin, respectively. The expression of apolipoprotein A-II was higher in the Wilms' tumor group than in the control group (P 〈0.01). By contrast, the expression of polyubiquitin was lower in the Wilms' tumor group than in the control group. Conclusion Apolipoprotein A-II and polyubiquitin may be used as potential biomarkers for nephroblastoma in children, and the analysis of apolipoprotein A-II may help diagnose and treat Wilms' tumor.
Background Angiogenesis and lymphogenesis which were promoted by vascular endothelial growth factor (VEGF) and VEGF-C are important in the growth and metastasis of solid tumors. The high level of VEGF and VEGF-C were distributed in numerous types of cancers, but their distribution and expression in Wilms tumor, the most common pediatric tumor of the kidney, was unclear. Methods To learn about the distribution, mass spectroscopy and immunohistochemistry were used to measure the level of VEGF and VEGF-C in serum and tissue of Wilms tumor. Results The expression level of VEGF in serum of Wilms tumor was the same as in pre-surgery and control, so it was the same case of VEGF-C. Both of these factors were chiefly located in Wilms tumor tissue, but not in borderline and normal. In addition, the higher clinical staging and histopathologic grading were important elements in high expression of VEGF and VEGF-C. Gender, age and the size of tumor have not certainly been implicated in expression level of VEGF and VEGF-C. Conclusions The lymph node metastasis and growth of tumors resulted from angiogenesis and lymphogenesis which were promoted by VEGF and VEGF-C in Wilms tumor. The autocrine and paracrine process of VEGF and VEGF-C were the principal contributor to specific tissues of Wilms tumor but not to the entire body.
WANG Lei ZHANG Da CHEN Xin-rang FAN Yu-xia WANG Jia-xiang