Patient-Derived Extracellular Vesicles Proteins as New Biomarkers in Multiple Myeloma - A Real-World Study

Identification of C4BPA as biomarker associated with immune infiltration and prognosis in breast cancer

Background

C4BPA is a gene that encodes the C4BP protein α chain and is involved in the complement system. C4BPA is regarded as a new biomarker for cancer, especially for non-small cell lung cancer and ovarian cancer. However, its role in breast cancer (BC) has not yet been determined.

Methods

In this research, we used a bioinformatics approach to assess the prognostic significance of C4BPA in BC. Utilizing a variety of databases and analysis tools, including The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), R, STRING, and the Kaplan-Meier plotter, we specifically assessed the connection between C4BPA and BC.

Results

C4BPA expression was markedly decreased in BC tissues compared to its expression in normal breast tissues (P<0.05). Additionally, a receiver operating characteristic (ROC) curve revealed that C4BPA has a significant capacity for prognostication and diagnostics. Additionally, C4BPA expression was linked to some immune infiltrating cells' functionality, according to gene set enrichment analysis (GSEA) and immune infiltration analysis. Low C4BPA expression was additionally related to poor progression-free interval (PFI) and overall survival (OS), according to the Kaplan-Meier method. We also found that C4BPA expression was independently connected to PFI and OS through Cox regression analysis. Finally, prognostic analysis of the various subgroups of breast invasive carcinoma (BRCA/BIC) in TCGA showed that patients with low C4BPA expression might have worse PFI and OS in patients with Luminal A compared to other BC subtypes.

Conclusions

In conclusion, these results revealed that C4BPA could potentially act as a diagnostic biomarker for BC patients indicating unfavorable prognoses and offers valuable knowledge for creating therapeutics and prognostic indicators.

Extracellular vesicles in hematological malignancies: EV-dence for reshaping the tumoral microenvironment

Following their discovery at the end of the 20th century, extracellular vesicles (EVs) ranging from 50-1,000 nm have proven to be paramount in the progression of many cancers, including hematological malignancies. EVs are a heterogeneous group of cell-derived membranous structures that include small EVs (commonly called exosomes) and large EVs (microparticles). They have been demonstrated to participate in multiple physiological and pathological processes by allowing exchange of biological material (including among others proteins, DNA and RNA) between cells. They are therefore a crucial way of intercellular communication. In this context, malignant cells can release these extracellular vesicles that can influence their microenvironment, induce the formation of a tumorigenic niche, and prepare and establish distant niches facilitating metastasis by significantly impacting the phenotypes of surrounding cells and turning them toward supportive roles. In addition, EVs are also able to manipulate the immune response and to establish an immunosuppressive microenvironment. This in turn allows for ideal conditions for heightened chemoresistance and increased disease burden. Here, we review the latest findings and reports studying the effects and therapeutic potential of extracellular vesicles in various hematological malignancies. The study of extracellular vesicles remains in its infancy; however, rapid advances in the analysis of these vesicles in the context of disease allow us to envision prospects to improve the detection and treatment of hematological malignancies.

Multiple Myeloma-Derived Extracellular Vesicles Modulate the Bone Marrow Immune Microenvironment

Multiple myeloma (MM), the third most frequent hematological cancer worldwide, is characterized by the proliferation of neoplastic plasma cells in the bone marrow (BM). One of the hallmarks of MM is a permissive BM microenvironment. Increasing evidence suggests that cell-to-cell communication between myeloma and immune cells via tumor cell-derived extracellular vesicles (EV) plays a key role in the pathogenesis of MM. Hence, we aimed to explore BM immune alterations induced by MM-derived EV. For this, we inoculated immunocompetent BALB/cByJ mice with a myeloma cell line, MOPC315.BM, inducing a MM phenotype. Upon tumor establishment, characterization of the BM microenvironment revealed the expression of both activation and suppressive markers by lymphocytes, such as granzyme B and PD-1, respectively. In addition, conditioning of the animals with MOPC315.BM-derived EV, before transplantation of the MOPC315.BM tumor cells, did not anticipate the disease phenotype. However, it induced features of suppression in the BM milieu, such as an increase in PD-1 expression by CD4+ T cells. Overall, our findings reveal the involvement of MOPC315.BM-derived EV protein content as promoters of immune niche remodeling, strengthening the importance of assessing the mechanisms by which MM may impact the immune microenvironment.