High-Throughput Tissue Microarray Analysis to Evaluate Genes Uncovered by cDNA Microarray Screening in Renal Cell Carcinoma

Abstract

Many genes and signaling pathways are involved in renal cell carcinoma (RCC) development. However, genetic tumor markers have not gained use in RCC diagnostics and prognosis prediction. Identification and evaluation of new molecular parameters are of utmost importance in cancer research and cancer treatment. Here we present a novel approach to rapidly identify clinically relevant molecular changes in cancer. To identify genes with relevance to RCC, a cDNA array analysis was first performed on 5184 cDNA clones on a filter to screen for genes with differential expression between the renal cancer cell line CRL-1933 and normal kidney tissue. There were 89 differentially expressed genes in the cancer cell line, one of them coding for vimentin, a cytoplasmic intermediate filament. In a second step, a renal cancer tissue microarray containing 532 RCC specimen was used to determine vimentin expression by immunohistochemistry. Vimentin expression was seen frequently in clear cell (51%) and papillary RCC (61%), but rarely in chromophobe RCC (4%) and oncocytomas (12%). Furthermore, vimentin expression was significantly associated with poor patient prognosis (P < 0.007) independent of grade and stage. These results obtained from minute arrayed tumor samples match well with previous findings on vimentin expression in renal tumors. It is concluded that the combination of tumor arrays and cDNA arrays is a powerful approach to rapidly identify and further evaluate genes that play a role in tumor biology.

Prognostic significance of mammalian sterile20-like kinase 1 in colorectal cancer

“…The tissue microarray technique is an accepted tool of investigation, especially when a huge number of samples are analyzed. 18,[23][24][25][26][27][28] The randomization of the study population into two subgroups allowed us to determine the best cutoffs for cytoplasmic and nuclear Mst1 expression on the first subgroup (N ¼ 599) based on the ROC curve analysis and to apply the determined cutoffs on the second subgroup (N ¼ 598) as well as on the third group (N ¼ 141). This approach has the important advantage of avoiding a scoring system that includes a subjectively selected cutoff or a complex composite scoring system.…”

CD10 is expressed in a subset of chromophobe renal cell carcinomas

“…Data about the expression profiling of renal epithelial neoplasms have been growing in the recent literature 15,[19][20][21][22] and the search for immunohistochemical markers uniquely positive for the most common renal cell neoplasms is extensive. 5,13,15,[22][23][24][25] CD10 has been suggested as a marker useful in the differential diagnosis of renal tumors.…”

Fabrication of Hydrogel Particles of Defined Shapes Using Superhydrophobic‐Hydrophilic Micropatterns

“…25,26 Micro-patterned arrays have been generated by immobilizing hydrogels on different micro-domains within a plane surface, and they have been used for disease diagnosis, prognosis, biochemical analysis, and therapeutic regimes, and have become an alternative approach for high-throughput multiplexed assays. [27][28][29][30] Strategies avoiding such 2D fixation of various hydrogels have employed shape-coded hydrogel particles as a suspension microarray format for multiplexed bioassays. 31,32 Here we describe a method for the rapid fabrication of alginate hydrogel particles of defined sizes and shapes using the effect of discontinuous dewetting on an SH-SL microarray combined with the sandwiching method to achieve the simultaneous gelation of the pre-hydrogel droplets.…”