Proteomic Profiling Differentiates Lymphoma Patients with and without Concurrent Myeloproliferative Neoplasia

Abstract

Myeloproliferative neoplasia (MPN) and lymphoma are regarded as distinct diseases with different pathogeneses. However, patients that are diagnosed with both malignancies occur more frequently in the population than expected. This has led to the hypothesis that the two malignancies may, in some cases, be pathogenetically related. Using a mass spectrometry-based proteomic approach, we show that pre-treatment lymphoma samples from patients with both MPN and lymphoma, either angioimmunoblastic T-cell lymphoma (MPN-AITL) or diffuse large B-cell lymphoma (MPN-DLBCL), show differences in protein expression compared with reference AITL or DLBCL samples from patients without MPN. A distinct clustering of samples from patients with and without MPN was evident for both AITL and DLBCL. Regarding MPN-AITL, a pathway analysis revealed disturbances of cellular respiration as well as oxidative metabolism, and an immunohistochemical evaluation further demonstrated the differential expression of citrate synthase and DNAJA2 protein (p = 0.007 and p = 0.015). Interestingly, IDH2 protein also showed differential expression in the MPN-AITL patients, which contributes to the growing evidence of this protein's role in both myeloid neoplasia and AITL. In MPN-DLBCL, the disturbed pathways included a significant downregulation of protein synthesis as well as a perturbation of signal transduction. These results imply an underlying disturbance of tumor molecular biology, and in turn an alternative pathogenesis for tumors in these patients with both myeloid and lymphoid malignancies.

Keywords: angioimmunoblastic T-cell lymphoma (AITL); diffuse large B-cell lymphoma (DLBCL); myeloproliferative neoplasia (MPN); proteomics.

Figure 1

Differentially expressed proteins. (A) Proteomic analysis revealed 20 significantly differentially expressed proteins between the MPN-AITL and R-AITL biopsies. The grey horizontal line marks the threshold of p < 0.05 of significantly expressed proteins. Green: downregulated. Red: upregulated. (B) Proteomic analysis showed 34 significantly differentially expressed proteins between the MPN-DLBCL and R-DLBCL biopsies. The grey horizontal line marks the threshold of p < 0.05 of significantly expressed proteins. Green: downregulated. Red: upregulated. (C) PCA with input of the 20 differentially expressed proteins revealed distinct clustering between the MPN-AITL and R-AITL specimens. Dark grey represents the R-AITL samples and light grey represents the MPN-AITL samples. (D) PCA with input of the 34 differentially expressed proteins showed clustering between the MPN-DLBCL and R-DLBCL specimens, with the exception of two samples. Dark grey represents R-DLBCL samples and light grey represent MPN-DLBCL samples. Abbreviations: AITL, angioimmunoblastic T-cell lymphoma; DLBCL, diffuse large B-cell lymphoma; MPN, myeloproliferative neoplasia; PCA, principal component analysis; R-, reference sample.

Figure 2

Immunohistochemical evaluation of selected proteins. (A) Representative images of IDH2 protein staining expression (B) AFs of strong and intermediate intensity staining of IDH2 protein. * denote MPN-AITL patient with two known IDH2 gene mutations. (C) IDH2 protein expression identified by MS-based proteomics analysis. (D) Representative images of DNAJA2 staining expression. (E) AFs of all positive DNAJA2 protein staining. (F) DNAJA2 protein expression identified by MS-based proteomics analysis. (G) Representative images of citrate synthase staining expression. (H) AFs of all positive citrate synthase staining. (I) Citrate synthase protein expression identified by MS-based proteomics analysis. (J) Representative images of lactotransferrin staining expression. (K) AFs of all positive lactotransferrin staining. (L) Lactotransferrin protein expression identified by MS-based proteomics analysis. (M) Representative images of myeloblastin staining expression. (N) AFs of all positive myeloblastin staining. (O) Myeloblastin protein expression identified by MS-based proteomics analysis. Abbreviations: AF, area fraction; AITL, angioimmunoblastic T-cell lymphoma; DLBCL, diffuse large B-cell lymphoma; DNAJA2, DnaJ homolog subfamily A member 2; IDH2, isocitrate dehydrogenase 2; LFQ, label free quantification; MPN, myeloproliferative neoplasia; R-, reference sample.

Figure 3

Ingenuity pathway analysis in MPN-AITL and R-AITL patients. Significantly disturbed pathways between the MPN-AITL and R-AITL specimens showing shared proteins between the pathways. Abbreviations: VEGF, Vascular Endothelial Growth Factor; NFR2, nuclear factor erythroid 2-like 2.

Figure 4

Ingenuity pathway analysis in MPN-DLBCL and R-DLBCL patients. Significantly disturbed pathways between the MPN-DLBCL and R-DLBCL specimens showing shared proteins between the pathways. Abbreviations: GTP, guanosine triphosphate; CCR5, C-C chemokine receptor type 5; RhoGDI, Rho GDP-dissociation inhibitor; eIF4, eukaryotic initiation factor 4; p70S6K, Ribosomal protein S6 kinase beta-1; eIF2, eukaryotic initiation factor 2; mTOR, The mammalian target of rapamycin.