Low-grade gliomas (LGG) are infiltrative primary brain tumors that in 70% of the cases undergo anaplastic transformation, deeply affecting prognosis. However, the timing of progression is heterogeneous. Recently, the tumor microenvironment (TME) has gained much attention either as prognostic factor or therapeutic target. Through the release of extracellular vesicles, the TME contributes to tumor progression by transferring bioactive molecules such as microRNA. The aim of the study was to take advantage of glioma-associated stem cells (GASC), an in vitro model of the glioma microenvironment endowed with a prognostic significance, and their released exosomes, to investigate the possible role of exosome miRNAs in favoring the anaplastic transformation of LGG. Therefore, by deep sequencing, we analyzed and compared the miRNA profile of GASC and exosomes obtained from LGG patients characterized by different prognosis. Results showed that exosomes presented a different signature, when compared to their cellular counterpart and that, although sharing several miRNAs, exosomes of patients with a bad prognosis, selectively expressed some miRNAs possibly responsible for the more aggressive phenotype. These findings get insights into the value of TME and exosomes as potential biomarkers for precision medicine approaches aimed at improving LGG prognostic stratification and therapeutic strategies.
Geothermal-associated microbial communities remain poorly characterized in Central Asia. Here, shotgun metagenomics was used to compare microbial communities associated with thermally influenced substrates from the Chundzha and Rakhman geothermal systems in Kazakhstan. Six metagenomes representing three spatial replicates per site yielded approximately 6.5–7.3 Gb of clean sequence data per sample. Species-level richness showed a directional trend toward higher values in Chundzha, whereas Shannon diversity was similar between sites. Genus-level Bray–Curtis ordination showed apparent site-associated separation, with sampling site explaining 87.3% of the variation, although the effect was not statistically significant (PERMANOVA, R2 = 0.873, p = 0.10). Chundzha showed greater relative representation of several halophilic and halotolerant taxa, whereas Rakhman showed greater representation of soil-associated lineages. Broad COG and KEGG functional profiles were largely shared between sites. Several hydrogenase-, nitrogenase-, and RuBisCO-associated genes showed higher relative representation in Rakhman, whereas selected fermentation- and photosynthesis-associated functions were relatively higher in Chundzha; however, none of the targeted KO comparisons remained significant after FDR correction. These results indicate candidate taxonomic and functional patterns that should be regarded as exploratory because of the limited replication. The dataset provides a baseline for future genome-resolved and metatranscriptomic studies of geothermal-associated microbial communities in Kazakhstan.