The Next Generation of Laser Capture Microdissection: A Comparative Study

Abstract

Laser Capture Microdissection (LCM) has become an essential research technique in biomarker discovery. LCM allows for the isolation of pure cell populations from heterogeneous tissue samples and coupled with Reverse Phase Protein Arrays (RPPA), molecular protein profiling of disease mechanisms of action can be achieved with high accuracy. In this study, we compare both the Pixcel IIe system and the newly introduced AccuLift LCM system —focusing on their usage, effectiveness, and results from RPPA analysis. We followed the instruments’ manufacturing recommendations to isolate tumor cells from formalin fixed paraffin embedded (FFPE) tissue sections of five individual prostate cancer biopsies. Consistent with our laboratory procedures, slides were deparaffinized, dehydrated, and hematoxylin stained prior to microdissection. LCM caps were lysed with extraction buffer, obtained lysates were then printed onto nitrocellulose slides and stained with a selected group of antibodies for comparison purposes. Slides were scanned with a laser scanner and images analyzed with MicroVigene software. Our results showed a similar trend of protein expression from the RPPA analysis of the prostate tumors microdissected using both LCM instruments. There was no distinct difference on intensity values in three of the biopsie. Two of the five biopsies differ slightly on intensity values detected by the software analysis. These differences may be due to the type of caps used, amount of isolated tumor cells and/or sample loss during processing. Further experiments are needed with a larger set of samples to confirm these results.