Proteomics: techniques and applications in cancer research.
Proteomics can be defined as functional analysis of the full set of proteins by high-throughput technologies in a given system. The workflow of proteomics is a multi-step process comprising sample preparation, separation, quantification and identification of proteins. Due to the high complexity of different protein species and the wide dynamic range of protein amount within a cell system it is necessary to apply appropriate analysis methods. One approach is to separate proteins first by two-dimensional gel electrophoresis (2-DE) according to charge and molecular weight. Proteins are then fragmented and analyzed using matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Identification of proteins can be achieved by comparing the mass/charge-ratios of these peptides to respective databases. Proteome analysis with respect to the identification of disease-associated patterns of molecules in different tissues is in the early stages, because standardisation of these techniques often remains to be established. However, proteome analyses is a promising tool to obtain holistic insights into the physiological status of a cell or cellular system. Compared to RNA-based studies some advantages are obvious: (1) post-translational modifications, e. g. phosphorylation, contributing to the activity status can be detected at the protein level only, (2) RNA-levels do not necessarily coincide with protein levels for a particular gene, (3) feedback-mechanisms within regulatory pathways can control protein activity without measurable changes in mRNA content.
Schramm
A
A
University Children's Hospital of Essen, Germany.
Apostolov
O
O
Sitek
B
B
Pfeiffer
K
K
Stühler
K
K
Meyer
H E
HE
Havers
W
W
Eggert
A
A
D000465:Algorithms; D014408:Biomarkers, Tumor; D002471:Cell Transformation, Neoplastic; D002851:Chromatography, High Pressure Liquid; D019295:Computational Biology; D030562:Databases, Protein; D015180:Electrophoresis, Gel, Two-Dimensional; D025461:Feedback, Physiological; D005456:Fluorescent Dyes; D006801:Humans; D009363:Neoplasm Proteins / Q000276:immunology; D009369:Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D010641:Phenotype; D010766:Phosphorylation; D011506:Proteins / Q000032:analysis / Q000378:metabolism; D020543:Proteome / Q000032:analysis; D040901:Proteomics / Q000295:instrumentation / Q000379:methods; D012313:RNA / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D012106:Research; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014407:Tumor Cells, Cultured
D014408:Biomarkers, Tumor; D005456:Fluorescent Dyes; D009363:Neoplasm Proteins; D011506:Proteins; D020543:Proteome; D012333:RNA, Messenger; D012313:RNA