Project description:BackgroundAnaerotruncus colihomonis is a newly described bacterial genus and species isolated from the stool specimens of children. Its clinical significance, however, is unknown.AimsTo describe a case of A colihominis bacteraemia identified by 16S ribosomal RNA (rRNA) gene sequencing and provide an emended description of the species.MethodsAn unidentified anaerobic bacillus (strain HKU19) that stains Gram negative was subjected to characterisation by 16S rRNA gene sequencing, G+C content determination and electron microscopy.ResultsStrain HKU19 was isolated from the blood culture of a 78-year-old woman with nosocomial bacteraemia. It was found to be an anaerobic, non-motile, pleomorphic, thin bacillus that stains Gram negative. It produces Indole and utilises glucose and mannose. Identifying the strain to the species level was not possible by conventional phenotypic tests and commercial identification systems. The G+C content of strain HKU19 was found to be 53.43 mol%. A similarity of 99.3% nucleotide identities was found between the 16S rRNA gene sequence of strain HKU19 and that of A colihominis WAL 14 565(T), which was isolated from a human faecal specimen. In contrast with the original description of A colihominis, HKU19 was found to produce occasional oval, terminal spores, although the other phenotypic characteristics matched. Spores were also occasionally observed when the two previously reported strains were re-examined.ConclusionsAlthough the source of the bacteraemia in the patient cannot be determined, this report suggests that A colihominis is of clinical significance. Spore formation is proposed as an emended description of A colihominis.
Project description:Purpose: Gut microbiota is associated with the progression of brain tumor. However, the alterations in the gut microbiota during glioma growth and temozolomide (TMZ) therapy remains to be understood. Methods: C57BL/6 male mice were implanted with GL261 glioma cells. TMZ/sodium carboxymethyl cellulose (SCC) was administered by gavage for five consecutive days (from 8 to 12 days after implantation). Fecal samples were collected before (T0) and on days 7 (T1), 14 (T2), and 28 (T3) after implantation. The gut microbiota was analyzed using 16S ribosomal DNA sequencing followed by absolute and relative quantitation analyses. Results: Nineteen genera were altered during glioma progression with the most dramatic changes in Firmicutes and Bacteroidetes phyla. During glioma growth, Lactobacillus abundance decreased at the earlier stage of glioma development (T1), and then gradually increased (T2, T3); Intestinimonas abundance exhibited a persistent increase; Anaerotruncus showed a transient increase and then a subsequent decrease. Twenty genera altered following TMZ treatment. The enrichment of Akkermansia and Bifidobacterium was observed only at the early stage following TMZ treatment (T2), but not at the later stage (T3). Additionally, the decrease of Anaerotruncus was slighter in TMZ group at T3 comparing to the vehicle group. The abundance of Intestinimonas increased constantly during the progression of glioma, but was unaffected by TMZ. Conclusions: Glioma development and progression resulted in altered gut microbiota. TMZ reversed the decrease of Anaerotruncus in glioma at T3, and increased the abundance of Bifidobacterium with no influence on the increase of Intestinimonas. Short-term and long-term effects of TMZ treatment on the bacterial communities may be differential. This study will improve understanding the role of gut microbiota in glioma, and help develop gut microbiota as a potential therapeutic target.
Project description:Background: Ependymomas encompass multiple, clinically relevant tumor types based on localization and molecular profiles. Although tumors of the methylation class “spinal ependymoma” (SP-EPN) represent the most common intramedullary neoplasms in children and adults, their developmental origin is ill-defined, molecular data are scarce, and the potential heterogeneity within SP-EPN remains unexplored. The only known recurrent genetic events in SP-EPN are loss of chromosome 22q and NF2 mutations, but neither types and frequency of these alterations nor their clinical meaning have been described in a large, epigenetically defined series. Methods: We mapped SP-EPN transcriptomes (n=76) to developmental atlases of the developing and adult spinal cord to uncover potential developmental origins of these tumors. In addition, transcriptomic, epigenetic (n=234), genetic (n=140), and clinical analyses (n=115) were integrated for a detailed overview on this entity. Results: Integration of transcriptomic ependymoma data with single-cell atlases of the spinal cord identified mature adult ependymal cells to display highest similarities to SP-EPN. Unsupervised hierarchical clustering of tumor data together with integrated analysis of methylation profiles identified two molecular SP-EPN subtypes. Subtype 1 predominantly contained NF2 wild type sequences with regular NF2 expression but revealed more extensive copy number alterations. Subtype 2 harbored previously known germline or sporadic NF2 mutations and was NF2-deficient in most cases, more often showed multilocular disease, and demonstrated a significantly reduced progression-free survival. Conclusion: Based on integrated molecular profiling of a large tumor series we identify two distinct SP-EPN subtypes with important implications for genetic counseling, patient surveillance, and drug development priorities.
Project description:Background: Ependymomas encompass multiple, clinically relevant tumor types based on localization and molecular profiles. Although tumors of the methylation class “spinal ependymoma” (SP-EPN) represent the most common intramedullary neoplasms in children and adults, their developmental origin is ill-defined, molecular data are scarce, and the potential heterogeneity within SP-EPN remains unexplored. The only known recurrent genetic events in SP-EPN are loss of chromosome 22q and NF2 mutations, but neither types and frequency of these alterations nor their clinical meaning have been described in a large, epigenetically defined series. Methods: We mapped SP-EPN transcriptomes (n=76) to developmental atlases of the developing and adult spinal cord to uncover potential developmental origins of these tumors. In addition, transcriptomic, epigenetic (n=234), genetic (n=140), and clinical analyses (n=115) were integrated for a detailed overview on this entity. Results: Integration of transcriptomic ependymoma data with single-cell atlases of the spinal cord identified mature adult ependymal cells to display highest similarities to SP-EPN. Unsupervised hierarchical clustering of tumor data together with integrated analysis of methylation profiles identified two molecular SP-EPN subtypes. Subtype 1 predominantly contained NF2 wild type sequences with regular NF2 expression but revealed more extensive copy number alterations. Subtype 2 harbored previously known germline or sporadic NF2 mutations and was NF2-deficient in most cases, more often showed multilocular disease, and demonstrated a significantly reduced progression-free survival. Conclusion: Based on integrated molecular profiling of a large tumor series we identify two distinct SP-EPN subtypes with important implications for genetic counseling, patient surveillance, and drug development priorities.
Project description:Background: Ependymomas encompass multiple, clinically relevant tumor types based on localization and molecular profiles. Although tumors of the methylation class “spinal ependymoma” (SP-EPN) represent the most common intramedullary neoplasms in children and adults, their developmental origin is ill-defined, molecular data are scarce, and the potential heterogeneity within SP-EPN remains unexplored. The only known recurrent genetic events in SP-EPN are loss of chromosome 22q and NF2 mutations, but neither types and frequency of these alterations nor their clinical meaning have been described in a large, epigenetically defined series. Methods: We mapped SP-EPN transcriptomes (n=76) to developmental atlases of the developing and adult spinal cord to uncover potential developmental origins of these tumors. In addition, transcriptomic, epigenetic (n=234), genetic (n=140), and clinical analyses (n=115) were integrated for a detailed overview on this entity. Results: Integration of transcriptomic ependymoma data with single-cell atlases of the spinal cord identified mature adult ependymal cells to display highest similarities to SP-EPN. Unsupervised hierarchical clustering of tumor data together with integrated analysis of methylation profiles identified two molecular SP-EPN subtypes. Subtype 1 predominantly contained NF2 wild type sequences with regular NF2 expression but revealed more extensive copy number alterations. Subtype 2 harbored previously known germline or sporadic NF2 mutations and was NF2-deficient in most cases, more often showed multilocular disease, and demonstrated a significantly reduced progression-free survival. Conclusion: Based on integrated molecular profiling of a large tumor series we identify two distinct SP-EPN subtypes with important implications for genetic counseling, patient surveillance, and drug development priorities.