A proteomic study of myeloproliferative neoplasms using reverse-phase protein arrays

Abstract

Myeloproliferative neoplasms polycythemia vera (PV), essential thrombocythaemia (ET) and primary myelofibrosis constitute a group of haematological diseases. The comprehensive assessment of signaling pathway activation in blood cells may aid the understanding of MPN pathophysiology. Thus, levels of post-translational protein modifications and total protein expression were determined in MPN patients and control leukocytes by using reverse-phase protein arrays (RPPA). Compared to control samples, p-SRC, p-CTNNB1, c-MYC, MCL-1, p-MDM2, BAX and CCNB1 showed higher expression in PV samples than controls. P-JAK2/JAK2 and pro-apoptotic BIM showed differential expression between JAK2V617F-positive and -negative ET patients. Apoptosis, cancer and PI3K/AKT pathways proteins showed differential expression among the studied groups. For most of the proteins analyzed using Western-Blot and RPPA, RPPA showed higher sensitivity to detect subtle differences. Taken together, our data indicate deregulated protein expression in MPN patients compared to controls. Thus, RPPA may be a useful method for broad proteome analysis in MPN patients´ leukocytes.

Keywords:

• Myeloproliferative neoplasms
• reverse-phase protein array
• global protein expression
• JAK2 mutation
• cell signaling pathways

Author contributions

RT designed and performed experiments, analysed data and wrote the paper. NSN performed experiments of the cell isolation and protein extraction. DCAS performed all the bioinformatics analysis. MR, RAR, FCA and LA performed RPPA and Western blotting experiments. EXS, BPS and LLP selected and diagnosed the MPN patients included in this study. RT, DAG, TR and FAC conceived the project, designed the study, discussed the results, searched for funding and wrote the paper. All authors critically reviewed the manuscript.

Disclosure statement

RT, NSN, DCAS, LA, FCA, LLP, EXS, BPS and FAC have no competing financial and/or non-financial interests to declare. MR, RAR, DAG and TR are employees of Novartis and declared no competing financial and/or non-financial interests to declare.

Additional information

Funding

This work was financed by grants from the Coordination for the Improvement of Higher Education Personnel (CAPES; Finance Code 001), the National Council for Scientific and Technological Development and the São Paulo Research Foundation (FAPESP; process no. 2011/51616-6 and 2011/20135-2).