EuPA Open Proteomics最新文献

We demonstrated here thanks to proteomic, that proprotein convertase 1/3 knockdown macrophages present all the characteristic of activated pro-inflammatory macrophages. TLR4 and TLR9 signaling pathways can be enhanced leading to the secretion of pro-inflammatory factors and antitumor factors. We can control their activation by controlling one enzyme, PC1/3. In a tumor context, PC1/3 inhibition in macrophages may reactivate them and lead to a cytokine storm after stimulation “at distance” with a TLR ligand. Therefore, we name these proprotein convertase inhibited macrophages the “drone macrophages”. They constitute an innovative cell therapy to treat efficiently tumors.

The growing understanding of the molecular mechanisms underlying epithelial-to-mesenchymal transition (EMT) may represent a potential source of clinical markers. Despite EMT drivers have not yet emerged as candidate markers in the clinical setting, their association with established clinical markers may improve their specificity and sensitivity. Mass spectrometry-based platforms allow analyzing multiple samples for the expression of EMT candidate markers, and may help to diagnose diseases or monitor treatment efficiently. This review highlights proteomic approaches applied to elucidate the differences between epithelial and mesenchymal tumors and describes how these can be used for target discovery and validation.

Malaria continues to affect 500 million people worldwide every year. In this study, we compared the protein profile of uninfected and Plasmodium berghei-infected serum samples by one dimensional SDS-PAGE analysis, MALDI-TOF/TOF mass spectrometry and confirmed by semi-quantitative RT-PCR. Also the protein interacting networks were established using STRING protein⿿protein interaction analysis. We observed for the first time the upregulation of FERM domain during P. berghei infection. We predict that FRMD5 along with the other protein partners (identified by STRING analysis) are involved in the merozoites entry or protein trafficking where cell to cell interaction happens with the host erythrocyte; hence, upregulation.

EWS-FLI1 expression in NIH-3T3 fibroblasts has a profound impact on the phenotype, resulting in the cytoskeleton and adhesive capacity disorganization (EF cells). Besides this, (R/W)₉, a cell-penetrating peptide (CPP), has an intrinsic actin remodeling activity in EF cells. To evaluate the impact of the oncogenic protein EWS-FLI1 on proteins expression levels, a quantitative comparison of tumoral EF and non-tumoral 3T3 proteomes was performed. Then to see if we could link the EWS-FLI1 oncogenic transformation to the phenotype reversion induced by (R/W)₉, (R/W)₉ influence on EF cells proteome was assessed. To our knowledge no such ⿿CPPomic⿿ study has been performed before.

Biological significance

Up to now very few global quantitative proteomic studies have been published to help understand the oncogenic transformation induced by EWS-FLI1 fusion protein and leading to Ewing sarcoma development and dissemination. The comparison we did in this study between a model tumoral cell line EF and its non-tumoral counterpart (3T3) allowed us to highlight several features either common to most tumor types or specific to Ewing sarcoma. Particularly, lack of actin cytoskeleton organization could very likely be explained by the down-regulation of many important actin binding proteins. These results are in accordance with the hypothesis of a passive/stochastic mode of dissemination conferring Ewing sarcoma tumoral cell a high metastatic potential.

Chlamydia trachomatis (Ct) is a human pathogen causing trachoma and infertility. We investigated acetylation at lysine residues of chlamydial antigenic proteins: major outer membrane protein (MOMP), 60 kDa chaperonin (chlamydial Hsp60), elongation factor G (EF-G), enolase and the polymorphic membrane proteins PmpB, PmpE and PmpF. 60 kDa chaperonin, EF-G and PmpB showed the highest degree of acetylation.

Our data show that important Ct antigens could be post-translationally modified by acetylation of lysine residues at multiple sites. Further studies are needed to investigate total acetylome of Ct and the impact PTMs might have on Ct biology and pathogenicity.