CA : A Cancer Journal for Clinicians

The importance of the gut-brain axis in maintaining homeostasis has long been appreciated. However, the past 15 yr have seen the emergence of the microbiota (the trillions of microorganisms within ...

The Microbiota-Gut-Brain Axis

Recently, more than 1000 large intergenic noncoding RNAs (lincRNAs) have been reported. These RNAs are evolutionarily conserved in mammalian genomes and thus presumably function in diverse biological processes. Here, we report the identification of lincRNAs that are regulated by p53. One of these lincRNAs (lincRNA-p21) serves as a repressor in p53-dependent transcriptional responses. Inhibition of lincRNA-p21 affects the expression of hundreds of gene targets enriched for genes normally repressed by p53. The observed transcriptional repression by lincRNA-p21 is mediated through the physical association with hnRNP-K. This interaction is required for proper genomic localization of hnRNP-K at repressed genes and regulation of p53 mediates apoptosis. We propose a model whereby transcription factors activate lincRNAs that serve as key repressors by physically associating with repressive complexes and modulate their localization to sets of previously active genes.

A Large Intergenic Noncoding RNA Induced by p53 Mediates Global Gene Repression in the p53 Response

Colonization resistance — protection from exogenous pathogens by commensal bacteria — can be mediated by direct antagonism and by indirect effects on the host immune response. This Review outlines our current knowledge of immune-mediated colonization resistance against clinically relevant, antibiotic-resistant intestinal pathogens and how insights into commensal bacterial species and their mechanisms might be therapeutically used to restore resistance.

http://www.unizar.es/depfarfi/unidad_fisiologia/Temas%20Teoria/Biotecnologia%20Aplicada/T5_Microbiota%20against%20pathogens.%20Nat%20Rev%20Immunol.%202013.pdf

Microbiota-mediated colonization resistance against intestinal pathogens.

A general consensus exists that IBD is associated with compositional and metabolic changes in the intestinal microbiota (dysbiosis). However, a direct causal relationship between dysbiosis and IBD has not been definitively established in humans. Findings from animal models have revealed diverse and context-specific roles of the gut microbiota in health and disease, ranging from protective to pro-inflammatory actions. Moreover, evidence from these experimental models suggest that although gut bacteria often drive immune activation, chronic inflammation in turn shapes the gut microbiota and contributes to dysbiosis. The purpose of this Review is to summarize current associations between IBD and dysbiosis, describe the role of the gut microbiota in the context of specific animal models of colitis, and discuss the potential role of microbiota-focused interventions in the treatment of human IBD. Ultimately, more studies will be needed to define host-microbial relationships relevant to human disease and amenable to therapeutic interventions.

Gut microbiota and IBD: causation or correlation?

Should we standardize the 1,700-year-old fecal microbiota transplantation?

Abstact
Background and Aim

The gut microbiota plays a pivotal role in the intestinal diseases. Fecal microbiota transplantation (FMT) might be a rescue therapy for refractory inflammatory bowel disease. This study aimed to evaluate the safety, feasibility, and efficacy of FMT through mid-gut for refractory Crohn's disease (CD).



Methods

We established standardized laboratory protocol and clinical work flow for FMT. Only refractory CD patients with Harvey–Bradshaw Index (HBI) score ≥ 7 were enrolled for this study. All included patients were treated with single FMT through mid-gut and assessed during follow-up.



Results

Metagenomics analysis showed a high concordance between feces sample and purified fecal microbiota from same donors. Standardized fecal microbiota preparation and clinical flow significantly simplified the practical aspects of FMT. Totally, 30 patients were qualified for the present analysis. The rate of clinical improvement and remission based on clinical activity at the first month was 86.7% (26/30) and 76.7% (23/30), respectively, which was higher than other assessment points within 15-month follow-up. Patients' body weight increased after FMT, and the lipid profile improved as well. FMT also showed a fast and continuous significant effect in relieving the sustaining abdominal pain associated with sustaining CD.



Conclusion

This is a pilot study with the largest sample of patients with refractory CD who underwent single FMT. The results demonstrated that FMT through mid-gut might be a safe, feasible, and efficient rescue therapy for refractory CD.

Fecal microbiota transplantation through mid-gut for refractory Crohn's disease: safety, feasibility, and efficacy trial results.

Recently, more and more evidence are rapidly accumulating that long noncoding RNAs (lncRNAs) are involved in human tumorigenesis and misregulated in many cancers, including colon cancer. LncRNA could regulate essential pathways that contribute to tumor initiation and progression with their tissue specificity, which indicates that lncRNA would be valuable biomarkers and therapeutic targets. Colon cancer-associated transcript 1 (CCAT1) is a 2628 nucleotide-lncRNA and located in the vicinity of a well-known transcription factor c-Myc. CCAT1 has been found to be upregulated in many cancers, including gastric carcinoma and colonic adenoma-carcinoma. However, its roles in colon cancer are still not well documented and need to be investigated. In this study, we aim to investigate the prognostic value and biological function of CCAT1 and discover which factors may contribute to the deregulation of CCAT1 in colon cancer. Our results revealed that CCAT1 was significantly overexpressed in colon cancer tissues when compared with normal tissues, and its increased expression was correlated with patients' clinical stage, lymph nodes metastasis, and survival time after surgery. Moreover, c-Myc could promote CCAT1 transcription by directly binding to its promoter region, and upregulation of CCAT1 expression in colon cancer cells promoted cell proliferation and invasion. These data suggest that c-Myc-activated lncRNA CCAT1 expression contribute to colon cancer tumorigenesis and the metastatic process and could predict the clinical outcome of colon cancer and be a potential target for lncRNA direct therapy.

C-Myc-activated long noncoding RNA CCAT1 promotes colon cancer cell proliferation and invasion

The concept of fecal microbiota transplantation (FMT) has been used in traditional Chinese medicine at least since the 4th century. Evidence from recent human studies strongly supports the link between intestinal bacteria and inflammatory bowel disease. We proposed that standardized FMT might be a promising rescue therapy for refractory inflammatory bowel disease. However, there were no reports of FMT used in patients with severe Crohn’s disease (CD). Here, we report the successful treatment of standardized FMT as a rescue therapy for a case of refractory CD complicated with fistula, residual Barium sulfate and formation of intraperitoneal large inflammatory mass. As far as we know, this is the first case of severe CD treated using FMT through mid-gut.

Zhining Fan

Papers

Should we standardize the 1,700-year-old fecal microbiota transplantation?

Fecal microbiota transplantation through mid-gut for refractory Crohn's disease: safety, feasibility, and efficacy trial results.

C-Myc-activated long noncoding RNA CCAT1 promotes colon cancer cell proliferation and invasion

Fecal microbiota transplantation for severe enterocolonic fistulizing Crohn’s disease

Klotho: a tumor suppressor and modulator of the Wnt/β-catenin pathway in human hepatocellular carcinoma.