Membrane-based laser microdissection in molecular oncology

Background: PCR analysis of tumour-specific genomic alterations depends on the selective procurement of the tumour cells. Membrane-based microdissecti on, first described in 1992, has emerged as a valuable tool for the selecti ve procurement of homogeneous cell populations from solid tumours, and prov ides good accuracy and correlation with standard histology. The incorporati on of laser technology, either infra-red or ultra-violet, has further incre ased its impact. Material and Methods:The feasibility of microbeam MOMeNT ( Microdissection Of Membrane-mounted Native Tissue) is demonstrated with an emphasis on membrane type and coupling medium. Results: Microbeam MOMeNT is a reliable method for the detection of tumour-specific alterations when us ing PCR assays. Homozygous deletions in the MTS1/CDKN2 tumour suppressor ge ne are demonstrated in bladder carcinomas. Ultra-thin (less than 2 mu m) po lyethylene terephthalate membranes and 70% ethanol as a coupling medium wor ked best in our hands. Conclusion: The re-evaluation of molecular markers o f solid tumours may be necessary from microdissected material.