Gut microbiome-derived bacterial extracellular vesicles in patients with solid tumours.

INTRODUCTION: Gut microbiome-derived nanoparticles, known as bacterial extracellular vesicles (bEVs), have garnered interest as promising tools for studying the link between the gut microbiome and human health. The diverse composition of bEVs, including their proteins, mRNAs, metabolites, and lipids, makes them useful for investigating diseases such as cancer. However, conventional approaches for studying gut microbiome composition alone may not be accurate in deciphering host-gut microbiome communication. In clinical microbiome research, there is a gap in the knowledge on the role of bEVs in solid tumor patients. OBJECTIVES: Analyzing the functionality of bEVs using (meta)genomics and proteomics could highlight the unique aspects of host-gut microbiome interactions in solid tumor patients. Therefore, we performed a comparative analysis of the proteome and microbiota composition of gut microbiome-derived bEVs isolated from patients with solid tumors and healthy controls. METHODS: After isolating bEVs from the feces of solid tumor patients and healthy controls, we performed spectrometry analysis of their proteomes and next-generation sequencing (NGS) of the 16S gene. We also investigated the gut microbiomes of feces from patients and controls using 16S sequencing and used machine learning to classify the samples into patients and controls based on their bEVs and fecal microbiomes. RESULTS: Solid tumor patients showed decreased microbiota richness and diversity in both the bEVs and feces. However, the bEV proteomes were more diverse in patients than in the controls and were enriched with proteins associated with the metabolism of amino acids and carbohydrates, nucleotide binding, and oxidoreductase activity. Metadata classification of samples was more accurate using fecal bEVs (100%) compared with fecal samples (93%). CONCLUSION: Our findings suggest that bEVs are unique functional entities. There is a need to explore bEVs together with conventional gut microbiome analysis in functional cancer research to decipher the potential of bEVs as cancer diagnostic or therapeutic biomarkers.

Transformation and survival in marginal zone lymphoma: a Finnish nationwide population-based study.

Marginal zone lymphoma (MZL) is an indolent B-cell malignancy with heterogeneous anatomical and clinical presentation. While MZLs are generally associated with long survival, some patients experience histological transformation to aggressive large B-cell lymphoma. Population-based long-term data on the transformation of MZL is limited. We conducted a nationwide population-based study to estimate the risk of transformation and relative survival in patients diagnosed with MZL in Finland from 1995-2018. We identified a total of 1454 patients with MZL from the Finnish Cancer Registry (FCR). The cumulative incidence of transformation was 4.7% (95% CI, 3.6-6.2) at 10 years. The highest incidence of transformation was observed in the patients with splenic MZL (14.0%; 95% CI, 8.6-22.7). The transformation was associated with a substantially increased risk of death (HR, 5.18; 95% CI, 3.58-7.50). Ten-year relative survival was 79% (95% CI, 73‒83%). Transformation, nodal MZL subtype, and older age at diagnosis were associated with increased excess mortality, whereas patients diagnosed at a later calendar period had a lower excess risk of death. We conclude that transformation resulted in a substantially increased mortality irrespective of MZL subtype compared with the patients without transformation. Our results also suggest a reduction in excess mortality in recent years.

Transformation and outcome of nodular lymphocyte predominant Hodgkin lymphoma: a Finnish Nationwide population-based study.

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is a rare B-cell malignancy associated with excellent survival. However, some patients experience histological transformation into aggressive large B-cell lymphoma. Population-based data on transformation in patients with NLPHL is limited. We conducted a nationwide population-based study to estimate the risk of transformation and relative survival in patients diagnosed with NLPHL in Finland between 1995 and 2018. We identified a total of 453 patients (median age, 48 years; 76% males) with the incident NLPHL from the Finnish Cancer Registry. The cumulative incidence of transformation was 6.3% (95% CI, 4.2-9.6) at 10 years. After adjusting for sex, age and year of diagnosis, transformation was associated with a substantially increased risk of death (HR 8.55, 95% CI 4.49-16.3). Ten-year relative survival was 94% (95% CI, 89%‒100%). The patients diagnosed at a later calendar year had lower excess risk of death (HR, 0.38 per 10-year increase; 95% CI, 0.15‒0.98). We conclude that while the 10-year relative survival for the patients with NLPHL was excellent in this large population-based cohort for the entire study period, transformation resulted in a substantially increased mortality compared with the patients without transformation. Our results also suggest a reduction in excess mortality over time.