Impact of ischemia and procurement conditions on gene expression in renal cell carcinoma.
Publication/Presentation Date
1-1-2013
Abstract
PURPOSE: Previous studies have shown that ischemia alters gene expression in normal and malignant tissues. There are no studies that evaluated effects of ischemia in renal tumors. This study examines the impact of ischemia and tissue procurement conditions on RNA integrity and gene expression in renal cell carcinoma.
EXPERIMENTAL DESIGN: Ten renal tumors were resected without renal hilar clamping from 10 patients with renal clear cell carcinoma. Immediately after tumor resection, a piece of tumor was snap frozen. Remaining tumor samples were stored at 4°C, 22°C, and 37°C and frozen at 5, 30, 60, 120, and 240 minutes. Histopathologic evaluation was conducted on all tissue samples, and only those with greater than 80% tumor were selected for further analysis. RNA integrity was confirmed by electropherograms and quantitated using RNA integrity number index. Altered gene expression was assessed by paired, two-sample t test between the zero time point and aliquots from various conditions obtained from the same tumor.
RESULTS: One hundred and forty microarrays were conducted. Some RNA degradation was observed 240 minutes after resection at 37°C. The expression of more than 4,000 genes was significantly altered by ischemia times or storage conditions. The greatest gene expression changes were observed with longer ischemia time and warmer tissue procurement conditions.
CONCLUSION: RNA from kidney cancer remains intact for up to 4 hours post surgical resection regardless of storage conditions. Despite excellent RNA preservation, time after resection and procurement conditions significantly influence gene expression profiles. Meticulous attention to preacquisition variables is of paramount importance for accurate tumor profiling.
Volume
19
Issue
1
First Page
42
Last Page
49
ISSN
1557-3265
Published In/Presented At
Liu, N. W., Sanford, T., Srinivasan, R., Liu, J. L., Khurana, K., Aprelikova, O., Valero, V., Bechert, C., Worrell, R., Pinto, P. A., Yang, Y., Merino, M., Linehan, W. M., & Bratslavsky, G. (2013). Impact of ischemia and procurement conditions on gene expression in renal cell carcinoma. Clinical cancer research : an official journal of the American Association for Cancer Research, 19(1), 42–49. https://doi.org/10.1158/1078-0432.CCR-12-2606
Disciplines
Medicine and Health Sciences
PubMedID
23136194
Department(s)
Department of Medicine
Document Type
Article