title: Tissue-based proteomics reveals FXYD3, S100A11 and GSTM3 as novel markers for regional lymph node metastasis in colon cancer.
abstract: Regional lymph node metastasis negatively affects prognosis in colon cancer patients. The molecular processes leading to regional lymph node metastasis are only partially understood and proteomic markers for metastasis are still scarce. Therefore, a tissue-based proteomic approach was undertaken for identifying proteins associated with regional lymph node metastasis. Two complementary tissue-based proteomic methods have been employed. MALDI imaging was used for identifying small proteins (≤25 kDa) in situ and label-free quantitative proteomics was used for identifying larger proteins. A tissue cohort comprising primary colon tumours without metastasis (UICC II, pN0, n = 21) and with lymph node metastasis (UICC III, pN2, n = 33) was analysed. Subsequent validation of identified proteins was done by immunohistochemical staining on an independent tissue cohort consisting of primary colon tumour specimens (n = 168). MALDI imaging yielded ten discriminating m/z species, and label-free quantitative proteomics 28 proteins. Two MALDI imaging-derived candidate proteins (FXYD3 and S100A11) and one from the label-free quantitative proteomics (GSTM3) were validated on the independent tissue cohort. All three markers correlated significantly with regional lymph node metastasis: FXYD3 (p = 0.0110), S100A11 (p = 0.0071), and GSTM3 (p = 0.0173). FXYD3 and S100A11 were more highly expressed in UICC II patient tumour tissues. GSTM3 was more highly expressed in UICC III patient tumour tissues. By our tissue-based proteomic approach, we could identify a large panel of proteins which are associated with regional lymph node metastasis and which have not been described so far. Here we show that novel markers for regional lymph metastasis can be identified by MALDI imaging or label-free quantitative proteomics and subsequently validated on an independent tissue cohort.
authors.affiliation: Institute of Pathology, Helmholtz Zentrum München, Neuherberg, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Meding
authors.forename: Benjamin
authors.initials: B
authors.lastname: Balluff
authors.forename: Mareike
authors.initials: M
authors.lastname: Elsner
authors.forename: Cédrik
authors.initials: C
authors.lastname: Schöne
authors.forename: Sandra
authors.initials: S
authors.lastname: Rauser
authors.forename: Ulrich
authors.initials: U
authors.lastname: Nitsche
authors.forename: Matthias
authors.initials: M
authors.lastname: Maak
authors.forename: Alexander
authors.initials: A
authors.lastname: Schäfer
authors.forename: Stefanie M
authors.initials: SM
authors.lastname: Hauck
authors.forename: Marius
authors.initials: M
authors.lastname: Ueffing
authors.forename: Rupert
authors.initials: R
authors.lastname: Langer
authors.forename: Heinz
authors.initials: H
authors.lastname: Höfler
authors.forename: Helmut
authors.initials: H
authors.lastname: Friess
authors.forename: Robert
authors.initials: R
authors.lastname: Rosenberg
authors.forename: Axel
authors.initials: A
authors.lastname: Walch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000556:secondary*; D005260:Female; D005982:Glutathione Transferase / Q000378:metabolism*; D006801:Humans; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D011379:Prognosis; D040901:Proteomics; D009418:S100 Proteins / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D014408:Biomarkers, Tumor; C091777:FXYD3 protein, human; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D009418:S100 Proteins; C072337:S100A11 protein, human; C483009:GSTM3 protein, human; D005982:Glutathione Transferase