title: Mass spectrometric proteomics profiles of in vivo tumor secretomes: capillary ultrafiltration sampling of regressive tumor masses.
abstract: Identification of in vivo secreted peptides/proteins (secretomes) in tumor masses has the potential to provide important biomarkers and therapeutic targets for cancer therapy. However, limitations of existing technologies have made obtaining these secretomes for analysis extremely difficult. Here we employed an in vivo sampling technique using capillary ultrafiltration (CUF) probes to collect secretomes directly from tumor masses. Mass spectrometric proteomics approaches were then used to identify the tumor secretomes. A UV-induced skin fibrosarcoma cell line (UV-2240) was subcutaneously injected into C3H/NeH mice, resulting in tumor masses that initially progressed, then regressed and eventually eradicated. We then implanted CUF probes into tumor masses at the progressive and regressive stage. Five secreted proteins (cyclophilin-A, S100A4, profilin-1, thymosin beta 4 and 10), previously associated with tumor progression, were identified from tumor masses at the progressive stage. Five secreted proteins including three protease inhibitors (fetuin-A, alpha-1 antitrypsin 1-6, and contrapsin) were identified from tumor masses at the regressive stage. The technique involving CUF probes linked to mass spectrometric proteomics reinforces systems biology studies of cell-cell interactions and is potentially applicable to the discovery of in vivo biomarkers in human disease.
authors.affiliation: Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA. chunming@ucsd.edu
authors.forename: Chun-Ming
authors.initials: CM
authors.lastname: Huang
authors.forename: Honnavara N
authors.initials: HN
authors.lastname: Ananthaswamy
authors.forename: Stephen
authors.initials: S
authors.lastname: Barnes
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Ma
authors.forename: Mikako
authors.initials: M
authors.lastname: Kawai
authors.forename: Craig A
authors.initials: CA
authors.lastname: Elmets
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D015180:Electrophoresis, Gel, Two-Dimensional; D051379:Mice; D008809:Mice, Inbred C3H; D008819:Mice, Nude; D023421:Models, Animal; D009368:Neoplasm Transplantation; D009369:Neoplasms / Q000098:blood supply / Q000378:metabolism*; D011506:Proteins / Q000032:analysis* / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D014462:Ultrafiltration / Q000379:methods*
chemical_list: D011506:Proteins; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C470944:S100a4 protein, mouse