A combined laser microdissection and mass spectrometry method for proteomic analysis of tissue sections for the indentification of tumor signatures

Clinical and biological samples : opportunities and challenges for translational research

A challenge in oncology is to better define thetumor of the patient to study the pathology and of course to find and to usethe right treatment. Genetic and transcriptomic analyses allow a cancerclassification, and give a lot of informations concerning carcinogenesis.However, the proteomic analysis can complete the genomic analysis and precisethe tumor features.

With the Frederic Saltel’s group within theINSERM 1053 Unit of Bordeaux, we have already developed a new method ofproteomic analysis of subcellular compartments after laser microdissection thathas been the object of a patent registration. Resulting from a know-howacquired during the development of this new method, we have developed aprocedure combining laser microdissection and mass spectrometry analysis toidentify and compare the levels of protein expression between two tissuespieces of formalin fixed paraffin embedded tissue sections. Our approachpresents the principal advantage to be compatible with biopsy, the currentbiological material available for clinical assays. Moreover, with this approachwe will obtain quantitative data in comparison with classicalimmunohistochemistry.

Our subject of study in the laboratory is thehepatocellular carcinoma (HCC), the sixth most prevalent cancer and the thirdmost frequent cause of cancer-related death. We already validated our protocolon two cases of HCC and one low-grade dysplastic nodule, one of the earlierstages of liver carcinogenesis. Now, we want to enlarge our analyses on abigger cohort to compare the proteome of the different stages of livercarcinogenesis. We will use the proteomic data to generate proteomic signaturesof each stage of liver carcinogenesis and validate the signatures generated.Finally we will propose a new tool for tumor characterization and biomarkersquantification that can be applicable in clinic.

Cette présentation a été donnée dans le cadre du BRIO SIRICscientific day 3 organisé annuellement par le SIRIC BRIO et qui a pour but deréunir tous les acteurs du SIRIC BRIO et plus largement de la cancérologie àBordeaux.