Proteomic and phosphoproteomics profiling of breast cancer cells with altered expression level of the protein phosphatase TRAP

ABSTRACT: Tartrate-resistant acid phosphatase (TRAP/ACP5) is a metalloenzyme of the group of acid phosphatases. High levels of TRAP protein have been associated with the development of cancer metastasis and with clinically relevant parameters of cancer progression and cancer aggressiveness. In order to investigate the molecular pathways responsible for the role of TRAP in such cancer related processes, we examined the changes in the proteome and phosphoproteome of MDA-MB-231 breast cancer cells determined by TRAP protein overexpression or knock-down. The dataset contains two different experimental setups. The first setup consists of the comparison between MDA-MB-231 breast cancer cells stably transfected with a full-length rat TRAP (TRAP3high) and MDA-MB-231 cells transfected with a mock insert (ctrl). The second setup consists of the comparison between TRAP3high cells transfected with a scrambled shRNA (scr) and TRAP3high cells transfected with either of two shRNAs targeting TRAP (sh2 and sh3+4). In the first experimental setup, we performed quantitative phosphoproteomic and proteomic analyses using SILAC. The two analyses identified respectively 3,290 unique phosphorylation sites corresponding to 1,059 genes, and 7,957 proteins corresponding to 7,846 genes. In the second experimental setup, we performed quantitative proteomics analysis using TMT, identifying 9,848 proteins corresponding to 9,189 genes. Integrated analysis of the generated data revealed a regulation of proteins involved in the cell adhesion process and extracellular matrix organization network. In particular, TGFβ isoform 2 (TGFβ2), TGFβ receptor type 1 (TβR1) and SMAD2 protein levels were increased upon TRAP upregulation, as well as phosphorylation of CD44 on residues localized in the intracellular portion of the protein. Finally, these results were validated by functional blocking and chemical inhibition of TGFβ2/TβR, which decreased TRAP-dependent cell migration and proliferation, and by blocking of CD44, which reduced TRAP3high cell proliferation. Altogether, we show that TRAP promotes metastasis-related cell properties in breast cancer cells via TGFβ2/TβR and CD44, thereby identifying a potential signaling mechanism associated to TRAP action in breast cancer cells.

INSTRUMENT(S): LTQ Orbitrap Velos, Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Culture

DISEASE(S): Breast Cancer

SUBMITTER: Rui Branca  

LAB HEAD: Janne Lehtiö

PROVIDER: PXD006430 | Pride | 2017-09-04

REPOSITORIES: Pride