title: A novel histology-directed strategy for MALDI-MS tissue profiling that improves throughput and cellular specificity in human breast cancer.
abstract: We describe a novel tissue profiling strategy that improves the cellular specificity and analysis throughput of protein profiles obtained by direct MALDI analysis. The new approach integrates the cellular specificity of histology, the accuracy and reproducibility of robotic liquid dispensing, and the speed and objectivity of automated spectra acquisition. Traditional methodologies for preparing and analyzing tissue samples rely heavily on manual procedures, which for various reasons discussed, restrict cellular specificity and sample throughput. Here, a robotic spotter deposits micron-sized droplets of matrix precisely onto foci of normal mammary epithelium, ductal carcinoma in situ, invasive mammary cancer, and peritumoral stroma selected by a pathologist from high resolution histological images of sectioned human breast cancer samples. The location of each matrix spot was then determined and uploaded into the instrument to facilitate automated profile acquisition by MALDI-TOF. In the example shown, the different lesions were clearly differentiated using mass profiling. Further, the workflow permits a visual projection of any information produced from the profile analyses directly on the histological image for a unique combination of proteomic and histological assessment of sample regions. The higher performance characteristics offered by the new workflow promises to be a significant advancement toward the next generation of tissue profiling studies.
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA.
authors.forename: Dale S
authors.initials: DS
authors.lastname: Cornett
authors.forename: James A
authors.initials: JA
authors.lastname: Mobley
authors.forename: Eduardo C
authors.initials: EC
authors.lastname: Dias
authors.forename: Malin
authors.initials: M
authors.lastname: Andersson
authors.forename: Carlos L
authors.initials: CL
authors.lastname: Arteaga
authors.forename: Melinda E
authors.initials: ME
authors.lastname: Sanders
authors.forename: Richard M
authors.initials: RM
authors.lastname: Caprioli
mesh_terms: D000328:Adult; D000818:Animals; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D042282:Microdissection; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D046888:Tissue Array Analysis
chemical_list: D009363:Neoplasm Proteins