Workflows & Protocols: Laser Microdissection for Pathology and Cancer Research

Laser Microdissection was commercially developed* for more focused cancer research and mutation analysis. As some tumors need high purity to reveal their secret of the underlying mutation, a dedicated tool to extract microscopic amounts of pure tumor tissue - without any contaminating healthy cells - for unbiased and unmistakable downstream mutation analysis was re-created: laser capture. This technology evolved quickly and meanwhile conquered many different applications starting from pathology, to separate healthy from disease affected cells, through to neuroscience, developmental research or forensic research etc.

In Brazil, during the Leica LMD workshop series hosted by the Federal University of Paraná/UFPR and the Centro de Energia Nuclear na Agricultura/USP (CENA), oncology and pathology research were addressed besides others.

As a preparation exercise some enthusiastic customer prepared LMD membrane slides with different kinds of tumor samples which were brought to the workshops and tumor material was dissected and collected with the Leica LMD system. This supreme discipline for the upright Leica LMD systems was demonstrated by the Product Manager Dr. Falk Schlaudraff and afterwards successfully applied and succeeded by the attendees who brought the corresponding samples (Fig. 1, 2).

Tumor dissection is in particular interesting for LMD applications as pure tumor material is obtained for mutation analysis. Some types of cancer require high purity for downstream analysis as otherwise the true underlying mutation might be masked by signals of healthy DNA of surrounding cells which are not affected by the tumor so far. With the Leica LMD system a slide with tumor tissue can be observed and pure tumor material can be selected and dissected for downstream analysis to ensure 100% pure starting material without any risk of cross contamination with healthy cells (Fig. 3, 4).

Furthermore some tumors are heterogeneous: subareas of the tumor can have different mutations. Again the Leica LMD system allows to specifically target different tumor areas and collect those into different collection vessels to get a clear picture of individual subareas of the same tumor. Small metastasis can be dissected providing pure tumor tissue for downstream analysis which is nearly impossible without laser microdissection.