epidermal-growth-factor and Wilms-Tumor

To designate the probable most important differentially expressed genes and genetic pathways in Wilms tumor and assess their expression and diagnostic potential by RT-PCR and statistical analysis. Systematic review of the literature and various bioinformatics analysis was carried out to gather and narrow down data. The expression of end-resulting genes was compared in Wilms tumor and normal tissue samples using RT-PCR. Statistical tests reported the diagnostic accuracy of genes and their correlation with clinicopathological features. Four genes including CDH1, NCAM1, EGF, and IGF2 were designated. The panel combining them has 100% sensitivity and specificity in differentiating tumors from normal tissue. Eight pathways, most involved in cell-cell and cell-basal matrix junction interactions, were found to be associated with disease pathogenesis. The suggested genes should undergo further evaluation to be validated as diagnostic biomarkers. Further research on the eight proposed pathways is recommended.

Topics: Biomarkers; Computational Biology; Epidermal Growth Factor; Gene Expression Regulation, Neoplastic; Humans; Kidney Neoplasms; Wilms Tumor

The biological activities of cyclin-dependent, proline-directed protein kinases (PDPKs) are highly regulated by a complex series of protein phosphorylation/dephosphorylation reactions involving both catalytic and regulatory subunits. In this paper we report on the enzymatic activation of p34cdc2/p58Cyclin A PDPK by a protein kinase present in human cells that targets threonine-161 of Cdc2. An assay for this Cdc2 kinase-kinase (PK161) was developed and specific enzyme activity was detected in a variety of mammalian cells and tissues. PK161 activity was rapidly stimulated by epidermal growth factor in human A431 epidermoid carcinoma cells. The development of an assay selective for PK161 phosphotransferase activity afforded the partial purification of the enzyme from human Wilms' tumors. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining of highly purified enzyme preparations revealed the presence of phosphoproteins migrating at approximately 42-44 and approximately 95 kDa, respectively, which correlated with enzyme activity upon fast-protein liquid chromatography gel permeation chromatography. Further purification was accomplished by immobilized peptide substrate affinity chromatography. The ability of PK161 to phosphorylate and activate p34cdc2/p58Cyclin A PDPK was confirmed by the use of purified recombinant subunits. Polyclonal antibodies directed against the Xenopus MO15 gene product (a putative Cdc2-activating kinase) cross-reacted with the purified 42- to 44-kDa phosphoprotein, thus identifying the catalytic subunit of human PK161 as a human homologue of Xenopus p40MO15. Subsequent immunoprecipitation experiments with metabolically labeled A431 cells identified a approximately 95-kDa phosphoprotein that coprecipitated with the approximately 42-kDa catalytic subunit. Taken together, these findings identify a human Cdc2-activating kinase as a growth factor-responsive enzyme system that may participate in the acute activation of cyclin-dependent protein kinases observed in mammalian somatic cells.

Topics: Animals; Blood Platelets; CDC2 Protein Kinase; Chromatography, High Pressure Liquid; Enzyme Activation; Epidermal Growth Factor; Humans; Hydrogen-Ion Concentration; Immunosorbent Techniques; Kinetics; Phosphorylation; Protein Kinases; Recombinant Proteins; Threonine; Tumor Cells, Cultured; Wilms Tumor

Thirty-two surgical specimens and three cell lines of human gastric cancers were used for subcutaneous transplantation into nude mice, resulting in the establishment of eight (25%) xenografts from the surgical specimens and two (67%) from the cell lines. The localization of epidermal growth factor (EGF) in the surgical specimens and cell lines of the gastric cancers and their xenografts in nude mice was then investigated immunohistochemically. Epidermal growth factor was stained in the cytoplasm of the cancer cells, being detected in 16 (50%) of the 32 surgical specimens and in all of the cell lines. Seven (44%) of the sixteen EGF-positive surgical specimens and one (6%) of the 16 EGF-negative ones were tumorigenic in nude mice. All of the xenografts in nude mice were positive for EGF. The tumorigenicity of human gastric cancer xenografts in nude mice may, therefore, be correlated with the presence of EGF in cancer cells.

Topics: Adenocarcinoma; Adolescent; Adult; Aged; Animals; Carcinoma, Renal Cell; Epidermal Growth Factor; Female; Humans; Kidney Neoplasms; Male; Mice; Mice, Nude; Middle Aged; Neoplasm Metastasis; Neoplasm Transplantation; Staining and Labeling; Stomach Neoplasms; Tumor Cells, Cultured; Wilms Tumor