Yang Liu

Bio: Yang Liu is an academic researcher from Harbin Medical University. The author has contributed to research in topics: Dysbiosis & Gut flora. The author has an hindex of 8, co-authored 17 publications receiving 213 citations.

Alterations of the Gut Microbiota in Hashimoto's Thyroiditis Patients

Abstract: Background: Hashimoto's thyroiditis (HT) is an organ-specific autoimmune disease in which both genetic predisposition and environmental factors serve as disease triggers. Many studies have indicate...

Alterations in the gut microbiota and metabolite profiles of thyroid carcinoma patients

Abstract: The aim of our study was to investigate the relationship among the gut microbiota community, metabolite profiles and thyroid carcinoma (TC). First, 30 TC patients and 35 healthy controls (HCs) fecal samples were applied to characterize the gut microbial community using 16S rRNA gene sequencing. Differential microbiota compositions were observed, with significant enrichment of 19 and depletion of 8 genera in TC samples compared to those in HCs (Q value 1.0 and p < 0.05) were observed and correlated to each other. Eight metabolites combined with 5 genera were more effective in distinguishing TC patients from HCs (AUC = 0.97). In conclusion, our study presents a comprehensive landscape of the gut microbiota and metabolites in TC patients, and provides a research direction of the mechanism of interaction between gut microbiota alteration and TC pathogenesis.

Allicin Inhibits Proliferation and Invasion in Vitro and in Vivo via SHP-1-Mediated STAT3 Signaling in Cholangiocarcinoma.

Abstract: Background/aims Cholangiocarcinoma (CCA) is a malignant tumor that is resistant to chemotherapy, so new therapeutic agents are needed. Allicin which is rapidly converted from allin by allinase, is one of the most biologically active compounds in freshly crushed garlic and has been shown to have strong anti-tumor effects. Our aim was to explore the molecular mechanism by which allicin affects the cell proliferation and invasion of CCA. Methods Cell viability and apoptosis were measured using the CCK-8 assay, colony formation assay, and flow cytometry. Cell migration and invasion were evaluated by wound healing and Transwell assays, respectively. The expression of several proteins involved in cell apoptosis and invasion were assessed by Western blot. The activation of STAT3 signaling was detected by Western blot and immunofluorescence staining. The involvement of SHP-1 was determined using small interfering RNA (siRNA). Moreover, a nude mouse model of human CCA was established to assess the anti-tumor effects of allicin in vivo. Results Allicin significantly suppressed CCA cell proliferation by activating the caspase cascade, inducing apoptosis, and reducing the expression of proteins downstream of STAT3, such as B-cell lymphoma 2 (Bcl-2), while upregulating Bcl-2-associated X (Bax) protein. In addition, allicin inhibited the migration, invasion, and epithelial-mesenchymal transition (EMT) of CCA cells. Moreover, the protein expression of MMP-2 and MMP-9 was significantly downregulated in CCA cells treated with allicin compared with CCA cells treated with control. Mechanistic investigations indicated that allicin upregulated SHP-1 expression in CCA, and pervanadate treatment reversed the allicin-induced downregulation of STAT3. Moreover, suppression of SHP-1 by siRNA overturned the effect of allicin on the induction of SHP-1 and inhibition of STAT3 activation. Additionally, treatment with allicin attenuated tumor growth in the nude mouse model of CCA. Conclusions Our findings suggest that allicin suppresses cell proliferation and invasion via STAT3 signaling and may be a potential therapeutic agent for CCA.

Fusobacterium nucleatum Acts as a Pro-carcinogenic Bacterium in Colorectal Cancer: From Association to Causality.

Abstract: Colorectal cancer (CRC) is a common cancer worldwide with complex etiology. Fusobacterium nucleatum (F. nucleatum), an oral symbiotic bacterium, has been linked with CRC in the past decade. A series of gut microbiota studies show that CRC patients carry a high abundance of F. nucleatum in the tumor tissue and fecal, and etiological studies have clarified the role of F. nucleatum as a pro-carcinogenic bacterium in various stages of CRC. In this review, we summarize the biological characteristics of F. nucleatum and the epidemiological associations between F. nucleatum and CRC, and then highlight the mechanisms by which F. nucleatum participates in CRC progression, metastasis, and chemoresistance by affecting cancer cells or regulating the tumor microenvironment (TME). We also discuss the research gap in this field and give our perspective for future studies. These findings will pave the way for manipulating gut F. nucleatum to deal with CRC in the future.

Splenectomy Leads to Amelioration of Altered Gut Microbiota and Metabolome in Liver Cirrhosis Patients

Abstract: Dysbiosis of gut microbiota and metabolome is a frequently encountered condition in liver cirrhosis (LC) patients. The severity of liver dysfunction was found to be correlated with the degree of microbial dysbiosis. Several clinical studies have indicated liver function improvement after therapeutic splenectomy for LC induced hypersplenism. We sought to determine whether such post-splenectomy outcome is pertinent to modulation of the abnormal gut microenvironment in LC patients. A cross-sectional study including 12 LC patients and 16 healthy volunteers was first conducted, then a before-after study in the cohort of patients was carried out before and six months after splenectomy. Faecal samples were collected in hospital. Temporal bacterial (n=40) and metabolomics (n=30) profiling was performed using 16s rRNA gene sequencing and UPLC/MS respectively. Our results revealed that microbial composition in patients was clearly different from that in healthy controls, evidenced by considerable taxonomic variation. Along with improved liver function (Child-Pugh score), the patients also displayed similar gut microbiota profile and predicted metagenome function to that of healthy controls after splenectomy. Enterobacteriaceae and Streptococcaceae, two LC-enriched families showing positive relation with Child-Pugh score, exhibited significantly decreased abundance after splenectomy. At the genus level, 11 genera were differentially abundant between patients and healthy controls, but 9 genera of them restituted to normal levels by certain degree after splenectomy. PICRUSt analysis showed the relative abundance of 17 KEGG pathways were partially restored after splenectomy. Four of them were Amino acid related pathways: Lysine degradation, Tryptophan degradation, Amino acid metabolism and Protein digestion and absorption. These findings were supported by metabonomics results which showed that relative abundance of Amino acid and corresponding catabolites changed towards normal. In addition to the variations in the relative abundances of bacteria and metabolites, the correlation between them also altered in patients after splenectomy. Dysbiosis in gut microbiome and related metabolism of LC patients were partially corrected after splenectomy. Whether the improved gut microenvironment could prevent LC related complications and delay the progress of liver cirrhosis is a propitious objective for future study.

Metagenomic biomarker discovery and explanation

Abstract: This study describes and validates a new method for metagenomic biomarker discovery by way of class comparison, tests of biological consistency and effect size estimation. This addresses the challenge of finding organisms, genes, or pathways that consistently explain the differences between two or more microbial communities, which is a central problem to the study of metagenomics. We extensively validate our method on several microbiomes and a convenient online interface for the method is provided at http://huttenhower.sph.harvard.edu/lefse/.

MicroRNAs: Target Recognition and Regulatory Functions

Abstract: MicroRNAs (miRNAs) are endogenous ∼23 nt RNAs that play important gene-regulatory roles in animals and plants by pairing to the mRNAs of protein-coding genes to direct their posttranscriptional repression. This review outlines the current understanding of miRNA target recognition in animals and discusses the widespread impact of miRNAs on both the expression and evolution of protein-coding genes.

Phytochemicals in Cancer Treatment: From Preclinical Studies to Clinical Practice.

Abstract: Cancer is a severe health problem that continues to be a leading cause of death worldwide. Increasing knowledge of the molecular mechanisms underlying cancer progression has led to the development of a vast number of anticancer drugs. However, the use of chemically synthesized drugs has not significantly improved the overall survival rate over the past few decades. As a result, new strategies and novel chemoprevention agents are needed to complement current cancer therapies to improve efficiency. Naturally occurring compounds from plants known as phytochemicals, serve as vital resources for novel drugs and are also sources for cancer therapy. Some typical examples include taxol analogs, vinca alkaloids such as vincristine, vinblastine, and podophyllotoxin analogs. These phytochemicals often act via regulating molecular pathways which are implicated in growth and progression of cancer. The specific mechanisms include increasing antioxidant status, carcinogen inactivation, inhibiting proliferation, induction of cell cycle arrest and apoptosis; and regulation of the immune system. The primary objective of this review is to describe what we know to date of the active compounds in the natural products, along with their pharmacologic action and molecular or specific targets. Recent trends and gaps in phytochemical based anticancer drug discovery are also explored. The authors wish to expand the phytochemical research area not only for their scientific soundness but also for their potential druggability. Hence, the emphasis is given to information about anticancer phytochemicals which are evaluated at preclinical and clinical level.

How to treat cancer

Abstract: The present invention provides a method for treating cancer using a proteasome inhibitor. The present invention also provides a method of treating a patient suffering from cancer based on an increase in the expression level of NFκB as measured by the H score of the patient's tumor sample using the NFκB p65 IHC assay. The present invention also provides a method for determining whether to treat a patient with a proteasome inhibitor based on the level of NFκB p65 in the patient's tumor sample. The present invention relates to the discovery that patients suffering from cancer respond to treatment with proteasome inhibitors. [Selection] Figure 1