Combined analysis of mRNA and miRNA transcriptomes reveals the regulatory mechanism of Xanthomonas arboricola pv pruni resistance in Prunus persica.

BACKGROUND: Peach bacterial shot hole, caused by Xanthomonas arboricola pv pruni (Xap), is a global bacterial disease that poses a threat to the yield and quality of cultivated peach trees (Prunus persica). RESULTS: This study compared the mRNA and miRNA profiles of two peach varieties, 'Yanbao' (resistant) and 'Yingzui' (susceptible), after inoculation with Xap to identify miRNAs and target genes associated with peach tree resistance. mRNA sequencing results revealed that in the S0-vs-S3 comparison group, 1574 genes were upregulated and 3975 genes were downregulated. In the R0-vs-R3 comparison group, 1575 genes were upregulated and 3726 genes were downregulated. Through miRNA sequencing, a total of 112 known miRNAs belonging to 70 miRNA families and 111 new miRNAs were identified. Notably, some miRNAs were exclusively expressed in either resistant or susceptible varieties. Additionally, 59 miRNAs were downregulated and 69 miRNAs were upregulated in the R0-vs-R3 comparison group, while 46 miRNAs were downregulated and 52 miRNAs were upregulated in the S0-vs-S3 comparison group. Joint analysis of mRNA and miRNA identified 79 relationship pairs in the S0-vs-S3 comparison group, consisting of 48 miRNAs and 51 target genes. In the R0-vs-R3 comparison group, there were 58 relationship pairs, comprising 28 miRNAs and 20 target genes. Several target genes related to resistance, such as SPL6, TIFY6B, and Prupe.4G041800_v2.0.a1 (PPO), were identified through literature reports and GO/KEGG enrichment analysis. CONCLUSION: In conclusion, this study discovered several candidate genes involved in peach tree resistance by analyzing differential expression of mRNA and miRNA. These findings provide valuable insights into the mechanisms underlying resistance to Xap in peach trees.

miR-373 promotes invasion and metastasis of colorectal cancer cells via activating ERK/MAPK pathway.

To explore the relationship between miR-373 and the occurrence and development of colorectal cancer. Additionally, it aims to predict the potential cellular signaling pathways and regulatory mechanisms in which miR-373 may be involved and provides a theoretical basis and experimental evidence for the clinical application of miR-373 as a potential biomarker, molecular target, and prognostic indicator in colorectal cancer. Real-time quantitative PCR is used to analyze the expression of miR-373 in human colorectal cancer cell lines and normal human colonic epithelial cells. Further validation of the differential expression of miR-373 in colorectal cancer cell lines is being performed. Biological functions such as cell proliferation, invasion and apoptosis are being detected by MTT, CCK-8, transwell, cell cycle analysis, and flow cytometry experiments to verify the changes in the biological behavior of colon cancer cells after overexpression and interference of miR-373 in SW-480 cells and to explore the effects of miR-373 on cell proliferation, invasion, and apoptosis in colon cancer cells. Proteomic analysis is being conducted on proteins extracted from miR-373 overexpressing SW480 cells, and mass spectrometry is used for protein identification. GO, KEGG, and enrichment analysis are being employed to analyze the significantly differentially expressed proteins. The expression levels of pathway-related proteins are being verified using Western blot. Overexpression of miR-373 increased the invasive and metastatic ability of SW-480 cells; knockdown of miR-373 decreased the invasive and metastatic ability of SW-480 cells. However, there was no statistically significant effect on cell proliferation and apoptosis in SW-480 cells. Proteomic analysis identified 78 differentially expressed proteins based on fold change (FC) > 1.2 and P < 0.05. Annotation of differentially changed proteins revealed that the MAPK signaling pathway, PI3K-Akt signaling pathway, and FAK signaling pathway may play crucial roles in the migration and invasion of colorectal cancer. Western blot analysis showed that overexpression of miR-373 significantly increased the levels of p-ERK1/2 in SW480 cells. miR-373 may activate the ERK/MAPK signaling pathway to promote the invasion and migration of colorectal cancer cells.

Identification of tumor antigens and immune subtypes of hepatocellular carcinoma for mRNA vaccine development.

BACKGROUND: mRNA vaccines have been investigated in multiple tumors, but limited studies have been conducted on their use for hepatocellular carcinoma (HCC). AIM: To identify candidate mRNA vaccine antigens for HCC and suitable subpopulations for mRNA vaccination. METHODS: Gene expression profiles and clinical information of HCC datasets were obtained from International Cancer Genome Consortium and The Cancer Genome Atlas. Genes with somatic mutations and copy number variations were identified by cBioPortal analysis. The differentially expressed genes with significant prognostic value were identified by Gene Expression Profiling Interactive Analysis 2 website analysis. The Tumor Immune Estimation Resource database was used to assess the correlation between candidate antigens and the abundance of antigen-presenting cells (APCs). Tumor-associated antigens were overexpressed in tumors and associated with prognosis, genomic alterations, and APC infiltration. A consensus cluster analysis was performed with the Consensus Cluster Plus package to identify the immune subtypes. The weighted gene coexpression network analysis (WGCNA) was used to determine the candidate biomarker molecules for appropriate populations for mRNA vaccines. RESULTS: AURKA, CCNB1, CDC25C, CDK1, TRIP13, PES1, MCM3, PPM1G, NEK2, KIF2C, PTTG1, KPNA2, and PRC1 were identified as candidate HCC antigens for mRNA vaccine development. Four immune subtypes (IS1-IS4) and five immune gene modules of HCC were identified that were consistent in both patient cohorts. The immune subtypes showed distinct cellular and clinical characteristics. The IS1 and IS3 immune subtypes were immunologically "cold". The IS2 and IS4 immune subtypes were immunologically "hot", and the immune checkpoint genes and immunogenic cell death genes were upregulated in these subtypes. IS1-related modules were identified with the WGCNA algorithm. Ultimately, five hub genes (RBP4, KNG1, METTL7A, F12, and ABAT) were identified, and they might be potential biomarkers for mRNA vaccines. CONCLUSION: AURKA, CCNB1, CDC25C, CDK1, TRIP13, PES1, MCM3, PPM1G, NEK2, KIF2C, PTTG1, KPNA2, and PRC1 have been identified as candidate HCC antigens for mRNA vaccine development. The IS1 and IS3 immune subtypes are suitable populations for mRNA vaccination. RBP4, KNG1, METTL7A, F12, and ABAT are potential biomarkers for mRNA vaccines.

Identification and immune landscape analysis of fatty acid metabolism genes related subtypes of gastric cancer.

Fatty acid metabolism (FAM) is associated with prognosis and immune microenvironment remodeling in many tumors. It is currently unknown how FAM affects the immunological microenvironment and prognosis of Gastric cancer (GC). Therefore, the current work aims to categorize GC samples based on the expression status of genes involved in FAM and to identify populations that might benefit from immunotherapy. In total, 50 FAM genes associated with overall survival (OS) were determined through univariate Cox proportional hazard regression analysis by mining the public TCGA and GEO databases. The GSE84437 and TCGA-STAD cohort samples were divided into two clusters using the "NMF" R package. According to the survival curve, patients in Cluster-1 showed considerably longer OS than those in Cluster-2. Patients in Cluster-1 exhibited earlier T stages, more intestinal GCs, and were older. MSI molecular subtypes were mainly distributed in Cluster-1, while GS molecular subtypes were distributed primarily in Cluster-2. There were 227 upregulated and 22 down-regulated genes (logFC > 1 or logFC < - 1, FDR < 0.05) in Cluster-2 compared with Cluster-1. One hub module (edges = 64, nodes = 12) was identified with a module score of 11.636 through Cytoscape plug-in MCODE. KEGG and GO analysis showed that the hub genes were associated with the cell cycle and cell division. Different immune cell infiltrates profile, and immune pathway enrichment existed between the subtypes. In conclusion, the current findings showed that practically all immunological checkpoint and immunoregulatory genes were elevated in patients with Cluster-2 GC, indicating that FAM subtypes may be crucial in GC immunotherapy.

Long-term survival of patients with hepatocellular carcinoma with hepatic, pulmonary, peritoneal and rare colon metastasis: A case report.

BACKGROUND: Hepatocellular carcinoma (HCC) is a highly malignant cancer that often metastasizes and has a poor prognosis. Gastrointestinal tract metastases are rare, and colon metastases are even rarer. The long-term survival of patients with multiple intrahepatic and extrahepatic metastases, especially to the colon, has not been previously reported. CASE SUMMARY: We present an atypical clinical case of a patient with liver, right lung, peritoneal, and colon metastases diagnosed successively following hepatic resection for primary HCC. Comprehensive treatment, including partial liver, lung and colon resection, palliative management such as systemic chemotherapy, trans-arterial chemoembolization, targeted therapy with sorafenib, and cryotherapy were attempted. Despite his early metastases, the patient remained relatively healthy for 8 years after diagnosis. CONCLUSION: This case indicates that comprehensive treatment is beneficial for certain patients with metastatic HCC. Clinicians should be alert as to the possibility of rare site metastatic tumors that may be easily misdiagnosed as primary tumors.

HOXA11 promotes lymphatic metastasis of gastric cancer via transcriptional activation of TGFß1.

Most gastric cancer (GC) patients with early stage often have no lymph node (LN) metastases, while LN metastases appear in the advanced stage. However, there are some patients who present with early stage LN metastases and no LN metastases in the advanced stage. To explore the deeper molecular mechanisms involved, we collected clinical samples from early and advanced stage GC with and without LN metastases, as well as metastatic lymph nodes. Herein, we identified a key target, HOXA11, that was upregulated in GC tissues and closely associated with lymphatic metastases. HOXA11 transcriptionally regulates TGFß1 expression and activates the TGFß1/Smad2 pathway, which not only promotes EMT development but also induces VEGF-C secretion and lymphangiogenesis. These findings provide a plausible mechanism for HOXA11-modulated tumor in lymphatic metastasis and suggest that HOXA11 may represent a potential therapeutic target for clinical intervention in LN-metastatic gastric cancer.

Meta-analysis on the epidemiology of gastroesophageal reflux disease in China.

BACKGROUND: No large-scale epidemiological survey on the prevalence of gastroesophageal reflux disease (GERD) in China has been conducted. China has a large population and a complex geographical environment. It is important to understand the prevalence and spatial distribution of GERD in China. AIM: To explore the prevalence and the spatial, temporal, and population distributions of GERD in the natural Chinese population. METHODS: We searched Chinese and English databases for literature on the prevalence of GERD in the natural Chinese population. The prevalence of GERD was pooled using a random-effects meta-analysis model. Subgroup analysis was performed according to time, region, and population. We used ArcGIS software to draw statistical maps and trend analysis charts. Spatial autocorrelation analysis was carried out using Geoda software. Spearman correlation analysis was used to assess the spatial distribution relationship between GERD and upper digestive tract tumours. RESULTS: Altogether, 70 studies involving 276014 individuals from 24 provinces of China were included. The overall pooled prevalence of GERD was 8.7% (95%CI: 7.5%-9.9%) in mainland China. Over the past two decades, the prevalence of GERD in China has increased from 6.0% to 10.6%. GERD was more common in people aged 40-60, with body mass index ≥ 24, and of Uygur ethnicity. The prevalence was higher in the west and east than in the centre, and there may be a local spatial autocorrelation between the Qinghai-Tibet Plateau and the southeast. GERD was correlated with gastric (r = 0.421, P = 0.041) and oesophageal tumours (r = 0.511, P = 0.011) in spatial distribution. CONCLUSION: GERD is becoming common in China. The prevalence differs by region and population. The development of appropriate strategies for the prevention and treatment of GERD is needed.

Over-expression of NFYB affects stromal cells reprogramming and predicts worse survival in gastric cancer patients.

Gastric cancer (GC) is the fifth most common cancer worldwide and the third most fatal. Cancer-associated fibroblasts (CAFs) play an essential role in promoting the occurrence and development of gastric cancer in all stages. NFYB is highly expressed in multiple tumors and promotes tumor invasion, metastasis, and drug resistance, but its role in the occurrence and development of gastric cancer remains unclear. Hence, we used TCGA, TIMER, Kaplan-Meier Plot, and UALCAN databases to analyze the expression of NFYB in pan-cancers and assess its clinical prognostic value. We found that high expression of NFYB may be a promising prognostic biomarker in patients with gastric cancer. High expression of NFYB was associated with high T stage, high histological grade, diffuse gastric cancer, and early-onset GC. Moreover, High expression of NFYB was associated with CAFs infiltration in the GC microenvironment. The prognosis of GC patients with high expression of NFYB and high infiltration of CAFs was worse. Therefore, NFYB may serve as a potential prognostic biomarker in patients with GC.

Antisense long non-coding RNAs in gastric cancer.

Gastric cancer is a global health problem with high mortality. The incidence of gastric cancer has significant regional differences. Helicobacter pylori (H. pylori) infection and its interaction with epigenetics are closely related to the occurrence of gastric cancer. It is of great significance to explore the early diagnosis and effective therapeutic targets of gastric cancer. Emerging evidence indicates that antisense long non-coding RNAs (lncRNAs) are closely associated with various biological and functional aspects of gastric cancer. However, diverse antisense lncRNAs in gastric cancer have not been compiled and discussed. In this review, we summarize the predisposing factors and compile the interaction between H. pylori and epigenetics in gastric cancer. Moreover, we focus on the underlying molecular mechanism and regulatory role of each antisense lncRNA in gastric cancer. In addition, we provide a new insight into the potential diagnosis and treatment of antisense lncRNAs in gastric cancer.

Spatial-temporal Distribution and Influencing Factors of Helicobacter pylori Infection in Chinese Mainland, 2001-2020: A Systematic Review and Meta-Analysis.

BACKGROUND: The spatial-temporal distribution of Helicobacter pylori infection in China is poorly understood. We aimed to study the spatial-temporal distribution of H. pylori infection in Chinese mainland and to explore its influencing factors. MATERIALS AND METHODS: We searched the relevant literature from 2001 to 2021 and applied meta-analysis to obtain the pooled prevalence estimates of all studies and subgroups. Then, we used the pooled prevalence as the dependent variable for the following analysis, including time series analysis, statistical mapping, spatial autocorrelation analysis, and influencing factor analysis based on generalized additive model and panel data model. RESULTS: A total of 726 articles and 3,407,392 people were included. The pooled prevalence was 43.7% (95% confidence interval: 42.7%-44.8%). The prevalence decreased in the past 20 years, with high in the eastern and western regions and low in the central region. Qinghai Tibet Plateau and Guizhou Plateau were the high incidence areas of this disease. The intake of vegetable oil, aquatic products, meat, milk, per capita gross domestic product, and annual average humidity were significantly correlated with H. pylori. CONCLUSIONS: The prevalence of H. pylori is decreasing in Chinese mainland, but still high in underdeveloped areas. Appropriate strategies for the prevention need greater attention.

Overexpression of CISD1 Predicts Worse Survival in Hepatocarcinoma Patients.

Background: Ferroptosis plays a vital role in hepatocellular carcinoma (HCC). CISD1 is known to regulate ferroptosis negatively. However, the correlations of CISD1 to prognosis in HCC and its potential mechanism remain unclear. Aim: To investigate the expression level and prognostic value of CISD1 in HCC. Methods: Gene expression and clinical data for 33 cancer types in TCGA were downloaded from the UCSC Xena platform. Pan-cancer analysis was performed to determine the expression profile and prognostic value of CISD1 in human cancers. GEO datasets and Human Protein Atlas (HPA) were used to verify the mRNA and protein expression levels. The influence of CISD1 on clinical prognosis in HCC was evaluated using a Kaplan-Meier plotter. The PPI network was constructed using the STRING database and Cytoscape. GO and KEGG pathways were constructed using the "clusterProfiler" R package with the FDR cutoff of 0.05. The methylation at the CISD1 promoter was detected using UALCAN and GEO datasets. The correlations between CISD1 and HCC immune infiltrates were investigated via TIMER. Results: Pan-cancer analysis of TCGA data showed that CISD1 is differentially expressed in multiple tumors. Data of gene expression microarrays reveal that the mRNA expression of CISD1 is higher in HCC than that in normal tissue. The protein level of CISD1, validated by the Human Protein Atlas (HPA) database, was upregulated consistently with mRNA levels in HCC samples. High CISD1 expression was associated with better overall survival (OS), disease-free survival (DFS), disease-specific survival (DSS), and progression-free survival (PFS) in LGG, but with poorer OS, DFS, DSS, and PFS in LIHC. Protein-protein interaction (PPI) analysis and GO/KEGG analysis showed that the PPI network and GO term of CISD1 were mainly associated with energy and iron metabolism. Promoter hypomethylation correlated with overexpression of CISD1. CISD1 expression was positively correlated with infiltrating levels of CD8+ T cells, macrophages, neutrophils, and dendritic cells (DCs) in HCC. Conclusions: These findings suggest that hypomethylation of the CISD1 promoter increases its expression in HCC. CISD1 is associated with prognosis and immune infiltrating levels of CD8+ T cells, macrophages, neutrophils, and DCs in HCC patients. These findings suggest that CISD1 can be used as a prognostic biomarker for determining prognosis in HCC.

LncRNA OGFRP1 promotes angiogenesis and epithelial-mesenchymal transition in colorectal cancer cells through miR-423-5p/CTCF axis.

OBJECTIVE: To investigate the mechanism of lncRNA OGFRP1 affecting angiogenesis and epithelial-mesenchymal transition (EMT) in colorectal cancer (CRC) and provide a new target for the treatment of CRC. METHODS: The expressions of OGFRP1, miR-423-5p, and CTCF were measured in CRC cell lines (HT29, LoVo, HCT116, SW620, and SW480) and normal colonic epithelial cells NCM460. Gain and loss of function experiments were performed on HCT116 and SW620 cells, after which the proliferation, apoptosis, EMT, invasion, and migration of the cells were measured using CCK-8 and colony formation assays, flow cytometry, Western blotting, Transwell, and scratch assay. The transfected cells were incubated with human umbilical vein endothelial cells (HUVECs) to assess angiogenesis using tube formation assay. ELISA was performed to detect VEGF in the conditioned medium of HCT116 and SW620 cells. The interactions among OGFRP1, CTCF and miR-423-5p were validated by dual-luciferase reporter assay. RESULTS: CRC cell lines had increased expression levels of OGFRP1 and CTCF and a suppressed expression level of miR-423-5p when compared with NCM460 cells. Suppression on OGFRP1 or CTCF and overexpression of miR-423-5p led to inhibited proliferation, EMT, invasion and migration and increased apoptosis of HCT116 and SW620 cells. HUVECs incubated with cells transfected with si-OGFRP1, si-CTCF or miR-423-5p mimic had suppressed angiogenesis ability. The effect of OGFRP1 suppression in CRC cells could be counteracted by miR-423-5p inhibition. Both CTCF and OGFRP1 could bind to miR-423-5p. CONCLUSION: OGFRP1 promotes proliferation, EMT, and angiogenesis in CRC through miR-423-5p/CTCF axis.

Refractive lens power and lens thickness in children (6-16 years old).

To examine the refractive lens power (RLP) and lens thickness and their associated factors in children from North-Western China. Children from two schools (primary school and junior high school) in the North-Western Chinese province of Qinghai underwent a comprehensive ophthalmic examination including biometry and cycloplegic refractometry. The RLP was calculated using Bennett's equation. The study included 596 (77.9%) individuals (mean age: 11.0 ± 2.8 years; range: 6-16 years) with a mean axial length of 23.65 ± 1.24 mm (range: 20.02-27.96 mm). Mean lens thickness was 3.30 ± 0.16 mm (range: 2.85-3.99 mm) and mean RLP was 24.85 ± 1.98D (range: 19.40-32.97). In univariate analysis, girls as compared to boys had a significantly thicker lens and greater RLP, shorter axial length, smaller corneal curvature radius and shorter corneal curvature radius (all P < 0.001). Both sexes did not differ significantly in refractive error (P = 0.11) and corneal thickness (P = 0.16). RLP was positively associated with refractive error (correlation coefficient r = 0.33; P < 0.001) and lens thickness (r = 0.62; P < 0.001) and negatively with axial length (r = - 0.70; P < 0.001). In univariate analysis, RLP decreased significantly with older age in the age group from age 6-13, while it plateaued thereafter, with no significant difference between boys and girls. In multivariate regression analysis, a higher RLP was associated with younger age (P < 0.001; standard regression coefficient ß = - 0.07), female sex (P < 0.001; ß = - 0.08), shorter axial length (P < 0.001; ß = - 0.48) and higher lens thickness (P < 0.001; ß = 0.42). In Chinese children, RLP with a mean of 24.85 ± 1.98D decreases with older age, male sex, longer axial length, and thinner lens thickness. Changes in RLP and axial length elongation are important players in the emmetropization and myopization.

Positive expression of basic transcription factor 3 predicts poor survival of colorectal cancer patients: possible mechanisms involved.

Basic transcription factor 3 (BTF3) is associated with the development of several cancers. The aim of our study was to elucidate the role of BTF3 in colorectal cancer (CRC) tissues. CRC tissues or their paired adjacent noncancerous (ANCT) tissues were obtained from 90 patients who underwent operations in our hospital from November 2011 to December 2016, and then we implemented a gene microarray assay for detecting significant changes in gene expression and confirmed expression in tissues using immunohistochemistry and real-time PCR. We transfected or injected the silencing BTF3 (BTF3-siRNA) plasmid into cells and nude mice, and measured the tumorigenicity of CRC cells with flow cytometry and studied the expression level of BTF3 downstream genes (MAD2L2, MCM3 and PLK1) in CRC cells. BTF3 expression level was not only significantly higher in CRC tissue than in ANCT tissue (2.61 ± 0.07 vs 1.90 ± 0.03, P < 0.001) but BTF3-siRNA decreased tumor formation in a nude mice model. Furthermore, based on the data of gene microarray analysis, MAD2L2, MCM3 and PLK1 were detected as the downstream target genes of BTF3 and their expressions were positive related with BTF3 expression. Also, through transfecting BTF3-siRNA into HCT116 cells, we found that BTF3-siRNA could decrease cell viability and induced cell apoptosis and blocking the cell cycle. In conclusion, BTF3 is positively related to CRC and BTF3-siRNA attenuated the tumorigenicity of colorectal cancer cells via MAD2L2, MCM3 and PLK1 activity reduction.

Upregulation of microRNA-196a and microRNA-196b cooperatively correlate with aggressive progression and unfavorable prognosis in patients with colorectal cancer.

BACKGROUND: Both microRNA (miR)-196a and miR-196b are implicated in normal cell differentiation, proliferation, and in tumorigenesis of various cancer types. Especially, miR-196a exerts a pro-oncogenic influence in colorectal cancer (CRC) cells and miR-196b expression is upregulated in CRC tissues. The aim of this study was to evaluate the associations of miR-196a and miR-196b dysregulation with clinicopathological characteristics and prognosis in patients with CRC. METHODS: Quantitative real time-PCR (qRT-PCR) was performed to detect the expression levels of miR-196a and miR-196b in 126 pairs of fresh tumor samples matched with adjacent colorectal mucosa obtained from 126 patients with CRC. RESULTS: miR-196a and miR-196b expression levels in CRC tissues were significantly higher than those in adjacent colorectal mucosa (both P < 0.002). Interestingly, the expression levels of miR-196a in CRC tissues were positively correlated with those of miR-196b. Then, high miR-196a expression and high miR-196b expression, alone or in combination, were all statistically linked to the presence of lymph node metastasis, the poor differentiation grade, and the advanced TNM stage of CRC. Moreover, overall and disease-free survivals of CRC patients with high miR-196a expression, high miR-196b expression and miR-196a-high/miR-196b-high expression tended to be shorter than the corresponding control groups (log-rank statistic, all P < 0.001). Furthermore, multivariate analysis indicated miR-196a and/or miR-196b expression as independent prognostic indicators for CRC patients (all P < 0.05). CONCLUSIONS: Both miR-196a and miR-196b may be correlated with aggressive progression and unfavorable clinical outcome in CRC patients. Combined expression of miR-196a and miR-196b may be a promising biomarker in identifying a poor prognosis group of CRC.

Tandem mass spectrometric fragmentation behavior of lignans, flavonoids and triterpenoids in Streblus asper.

RATIONALE: An unambiguous identification of compounds can be achieved by comparison of known fragmentation patterns. While the literature about fragmentation mechanisms of lignans, flavonoids and triterpenoids is few. So the present study analyses the fragmentation mechanisms of these compounds isolated from Streblus asper. METHODS: Electrospray ionization ion trap mass spectrometry (ESI-ITMS) and atmospheric pressure chemical ionization ion trap mass spectrometry (APCI-ITMS) were used to obtain the MS(n) spectra of the compounds. By analyzing the differences between the ions, the fragmentation mechanisms of these compounds were explored. RESULTS: Of the 29 compounds detected, 17, 7, and 5 were lignans, flavonoids and triterpenoids, respectively. The majority of lignans were found to give [M - H](-) ions of sufficient abundance for MS(n) analyses. The flavonoids were prone to the loss of CO and H2O. The triterpenoids always lost one formic acid molecule and two hydrogens, or one H2O from [M - H](-) to form the most abundant product ion in the MS(n) spectrum. CONCLUSIONS: ESI/APCI-ITMS were demonstrated to be fast, effective and practical tools to characterize the structures of flavonoids, triterpenoids and lignans. Results of the present study can help identify the analogous constituents by analyzing their MS(n) spectra.

A new chromone from the twig of Mallotus apelta.

A new chromone, 7-hydroxy-2-hydroxymethyl-8-methoxy-4-oxo-4H-chromene-6-carboxylic acid, named melachromone, along with 13 known compounds (2-14), including chromones, flavonoids, coumarins and phenylpropane derivatives, were isolated from the twig of Mallotus apelta. Their chemical structures were elucidated by using various spectroscopic methods. Anti-tumour evaluation of the compounds suggested that compound 1 exhibited medium cytotoxic activity against KB and HeLa Cells, with IC50 values of 9.50 and 9.23 µg mL(-1), respectively.

MiR-137 regulates epithelial-mesenchymal transition in gastrointestinal stromal tumor.

Activation of the epithelial-to-mesenchymal transition (EMT) endows extraordinary invasive capability of cancer cells and causes of treatment failure and metastasis in gastrointestinal stromal tumor (GIST); however, the molecular mechanisms governing GIST invasion remain largely unknown. MicroRNAs (miRNAs) have been shown to play critical roles in cell motility and invasion, which promotes us to study the biological functions of miR-137 in the EMT of GIST. We have found that miR-137 was dramatically downregulated in clinical specimen of GIST. Using an in silico analysis approach, Twist1, a key regulator gene of EMT, has been identified as the target of miR-137. Quantitative RT-PCT and western blot were used to confirm that miR-137 directly targeted on Twist1 and repressed Twist1 expression in GIST-H1 human gastrointestinal stromal tumor cell line. Further, miR-137 was found to increase expression of E-cadherin and cytokeratin, but suppress expression of N-cadherin and vimentin. In vitro experiments have shown that miR-137 enhanced the epithelial cell morphology, decreased GIST cell migration, activated G1 cell cycle arrest, and induced cell apoptosis. These results suggest a novel mechanism that miR-137 regulates EMT and inhibits cell migration via Twist1 downregulation. Therefore, miR-137 may function as anti-migration and anti-metastasis in GIST and our study provides a potential approach for developing miR-137-based therapeutic strategy for GIST.

[GC-MS analysis of chemical components of volatile oil from Viburnm schensianum leaf and their antibacterial activity].

OBJECTIVE: To analyze the chemical constituents of the volatile oil from Viburnm schensianum leaves and investigate their antibacterial activity in vitro. METHODS: The volatile oil from Viburnm schensianum leaves were extracted by steam distillation. The chemical compositions were separated and analyzed by GC-MS. Their relative percentage content were calculated with peak area normalization method. Agar dilution method was used to determine the minimum inhibitory concentration of the volatile oil and Ciprofloxacin to the five kinds of experimental strains. RESULTS: 54 compounds were isolated and 45 compounds were identified. The volatile oil showed strong antibacterial activity against Staphyloccocus aureus, and the minimum inhibitory concentration was 0. 032 mg/mL. CONCLUSION: The main chemical constituents of the volatile oil are n-hexadecanoic acid (29.24%), 4-methy-l--(1-methylethyl)-bicyclo [3.1.0] hex-3-en-2-one (5.71%), 3-methyl-4-isopropylphenol (5.68%)and linolenyl alcohol (4.84%). The volatile oil has strong antibacterial activity against Staphyloccocus aureus.