A comprehensive database of exosome molecular biomarkers and disease-gene associations.

Exosomes play a crucial role in intercellular communication and can be used as biomarkers for diagnostic and therapeutic clinical applications. However, systematic studies in cancer-associated exosomal nucleic acids remain a big challenge. Here, we developed ExMdb, a comprehensive database of exosomal nucleic acid biomarkers and disease-gene associations curated from published literature and high-throughput datasets. We performed a comprehensive curation of exosome properties including 4,586 experimentally supported gene-disease associations, 13,768 diagnostic and therapeutic biomarkers, and 312,049 nucleic acid subcellular locations. To characterize expression variation of exosomal molecules and identify causal factors of complex diseases, we have also collected 164 high-throughput datasets, including bulk and single-cell RNA sequencing (scRNA-seq) data. Based on these datasets, we performed various bioinformatics and statistical analyses to support our conclusions and advance our knowledge of exosome biology. Collectively, our dataset will serve as an essential resource for investigating the regulatory mechanisms of complex diseases and improving the development of diagnostic and therapeutic biomarkers.

Characterization of tumour microenvironment reprogramming reveals invasion in epithelial ovarian carcinoma.

BACKGROUND: Patients with epithelial ovarian carcinoma (EOC) are usually diagnosed at an advanced stage with tumour cell invasion. However, identifying the underlying molecular mechanisms and biomarkers of EOC proliferation and invasion remains challenging. RESULTS: Herein, we explored the relationship between tumour microenvironment (TME) reprogramming and tissue invasion based on single-cell RNA sequencing (scRNA-seq) datasets. Interestingly, hypoxia, oxidative phosphorylation (OXPHOS) and glycolysis, which have biologically active trajectories during epithelial mesenchymal transition (EMT), were positively correlated. Moreover, energy metabolism and anti-apoptotic activity were found to be critical contributors to intratumor heterogeneity. In addition, HMGA1, EGR1 and RUNX1 were found to be critical drivers of the EMT process in EOC. Experimental validation revealed that suppressing EGR1 expression inhibited tumour cell invasion, significantly upregulated the expression of E-cadherin and decreased the expression of N-cadherin. In cell components analysis, cancer-associated fibroblasts (CAFs) were found to significantly contribute to immune infiltration and tumour invasion, and the accumulation of CAFs was associated with poorer patient survival. CONCLUSION: We revealed the molecular mechanism and biomarkers of tumour invasion and TME reprogramming in EOC, which provides effective targets for the suppression of tumour invasion.

Molecular characterization and transcriptional regulation analysis of the Torreya grandis squalene synthase gene involved in sitosterol biosynthesis and drought response.

The kernel of Torreya grandis cv. 'Merrillii' (Cephalotaxaceae) is a rare nut with a variety of bioactive compounds and a high economic value. ß-sitosterol is not only the most abundant plant sterol but also has various biological effects, such as antimicrobial, anticancer, anti-inflammatory, lipid-lowering, antioxidant, and antidiabetic activities. In this study, a squalene synthase gene from T. grandis, TgSQS, was identified and functionally characterized. TgSQS encodes a deduced protein of 410 amino acids. Prokaryotic expression of the TgSQS protein could catalyze farnesyl diphosphate to produce squalene. Transgenic Arabidopsis plants overexpressing TgSQS showed a significant increase in the content of both squalene and ß-sitosterol; moreover, their drought tolerance was also stronger than that of the wild type. Transcriptome data from T. grandis seedlings showed that the expression levels of sterol biosynthesis pathway-related genes, such as HMGS, HMGR, MK, DXS, IPPI, FPPS, SQS, and DWF1, increased significantly after drought treatment. We also demonstrated that TgWRKY3 directly bound to the TgSQS promoter region and regulated its expression through a yeast one-hybrid experiment and a dual luciferase experiment. Together, these findings demonstrate that TgSQS has a positive role in ß-sitosterol biosynthesis and in protecting against drought stress, emphasizing its importance as a metabolic engineering tool for the simultaneous improvement of ß-sitosterol biosynthesis and drought tolerance.

RNA modification "writer"-mediated RNA modification patterns and tumor microenvironment characteristics of cervical cancer.

PURPOSE: As an epigenetic regulation mechanism after transcription, RNA modification is installed by endogenous "writer" enzymes and is widely involved in a variety of physiological processes, including cancer progression. This study explored the RNA modification patterns of cervical cancer to clarify overall effect of RNA modification on tumor microenvironment (TME) characteristics and immune/targeted therapy. METHODS: 26 RNA modification "writers" were clustered, and the RNA modification patterns and TME characteristics of cervical cancer patients in TCGA were systematically evaluated. Based on differentially expressed genes (DEGs) between different RNA modification patterns, an RNA modification "writer" score (WM score) system was developed to assess the RNA modification of a single sample. RESULTS: Two different RNA modification patterns of cervical cancer were identified, and these patterns were significantly related to the prognosis and TME infiltration characteristics of patients. WM score was an independent risk factor for the prognosis of cervical cancer. High WM score was characterized by poor prognosis, low immune infiltration and low tumor mutation burden (TMB), while low-WM score was related to relatively long overall survival (OS), more immune components in TME and increased TMB. In addition, the low-WM score group was expected to be more sensitive to programmed cell death protein 1 (PD-1) therapy and showed lower predicted IC50 of chemotherapy drugs paclitaxel and cisplatin treatment. CONCLUSIONS: This study identified and characterized RNA modification patterns, and clarified potential relationship between RNA modification patterns and immune infiltration characteristics and immunotherapy of cervical cancer, offering a new evaluation scheme for treatment of cervical cancer patients.

Immune Characterization of Ovarian Cancer Reveals New Cell Subtypes With Different Prognoses, Immune Risks, and Molecular Mechanisms.

Ovarian cancer (OV) is a considerable threat to the health of women due to its complex mechanisms and atypical symptoms. Various currently available treatments fail to substantially increase the survival rate of OV patients. The tumor microenvironment (TME) is gaining attention due to its role in tumorigenesis and tumor progression. This study mainly investigated the immune characteristics of OV by CIBERSORT and MCP-counter. We reclassified OV into four TME cell subtypes with different prognoses and evaluated the infiltration of the cells in each subtype. The immune risk of diverse subtypes was evaluated based on the immunoscore calculated by Cox regression analysis. The molecular mechanisms and hallmark pathways of the four subtypes were analyzed. The results indicate that the immune procancer cell subtype is associated with the worst prognosis, closely related to the high immune risk group, and characterized by low expression of checkpoints and MHC class I and II molecules, high expression of hypoxia-related genes, high enrichment of the EMT and hypoxia pathways, and low enrichment of the DNA repair and interferon α response pathways. This study contributes to the investigation of immune mechanisms and identifies more effective targets for immunotherapy of OV.

In silico detection of potential prognostic circRNAs through a re-annotation strategy in ovarian cancer.

Ovarian cancer (OC) is the most common and lethal gynecologic malignancy. The pathophysiology of OC tumor development is complex and involves numerous biological pathways. Previous studies suggest that circular (circ)RNAs serve important roles in OC tumor pathology. In the present study, a re-annotation strategy was performed to evaluate the expression level of circRNAs based on a microarray dataset obtained from the Gene Expression Omnibus database. Univariate and multivariate Cox regression analyses were performed to evaluate the association between survival and expression of circRNAs in each OC cohort. An expression-based risk score model was constructed to extrapolate the prognostic efficacy of this signature. In the GSE9891 dataset, the 278 OC patients were randomly divided into training and validating groups. A six-circRNA signature was significantly associated with overall survival in the training and validating datasets. The risk score model was further validated in GSE63885 and GSE26193 datasets. The six-circRNA signature was also significantly associated with patient progression-free survival and disease-free survival. Further investigation revealed that the signature had higher area under the curve values than the existing clinical and other molecular signatures in predicting survival. In conclusion, the present study revealed that the six-circRNA signature may serve as a potential prognostic biomarker of OC.

Identification of potential prognostic TF-associated lncRNAs for predicting survival in ovarian cancer.

The pathophysiology of ovarian cancer (OV) is complex and depends on multiple biological processes and pathways. Therefore, there is an urgent need to identify reliable prognostic biomarkers for predicting clinical outcomes and helping personalize treatment of OV. A long non-coding RNA (lncRNA)-based risk score model was constructed to infer the prognostic efficacy of transcription factors (TFs) based on the OV dataset from The Cancer Genome Atlas. The risk score model was further validated in other independent cohorts from Gene Expression Omnibus. Time-dependent receiver operating characteristic curves were used to evaluate the survival prediction performance in comparison with other clinical and molecular variables. Our results revealed that the top-ranked TF-associating lncRNAs were significantly associated with overall survival, progression-free survival and disease-free survival. Stratification analysis according to clinical variables indicated the prognostic independence of POLR2A-associating lncRNAs. In comparison, the signature of POLR2A-associating lncRNAs was more sensitive and specific than existing clinical and molecular signatures. Functional and experimental analysis suggested that POLR2A-associating lncRNAs may be involved in known biological processes and pathways of OV. Our findings revealed that the lncRNA-based risk score model can provide helpful information on OV prognosis stratification and discovery of therapeutic biomarkers.

Abnormal activation of the sonic hedgehog signaling pathway in endometriosis and its diagnostic potency.

OBJECTIVE: To investigate the abnormal expression of sonic hedgehog (SHH) signaling molecules in 52 eutopic endometrial tissues and its diagnostic potency in endometriosis. DESIGN: Retrospective study. SETTING: University hospital. PATIENT(S): Twenty-six women with histologically confirmed endometriosis and 26 women with histologically normal endometria who were undergoing curettage or hysterectomy were selected. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The mRNA and protein levels of molecules in the SHH signaling pathway. RESULT(S): The levels of SHH, smoothened, GLI family zinc finger 3, and its downstream signaling transcription factor (GLI1) not only were upregulated in the eutopic endometrium of endometriosis compared with the control endometrium, but also independently predicted the onset and severity of the disease. CONCLUSION(S): This study is the first to reveal differences in the activation of the SHH signaling pathway between women with and without endometriosis and suggests that the SHH signaling pathway has potential in the diagnosis of endometriosis.

Constructing an ovarian cancer metastasis index by dissecting medical records.

Globally, ovarian cancer (OC) is the leading cause of gynecological cancer-associated deaths. Metastasis, especially multi-organ metastasis, determines the speed of disease progression. A multicenter retrospective study was performed to identify the factors that drive metastasis, from medical records of 534 patients with OC. The average number of target organs per patient was 3.66, indicating multi-organ metastasis. The most common sites of metastasis were large intestine and greater omentum, which were prone to co-metastasis. Results indicated that ascites and laterality, rather than age and menopausal status, were the potential drivers for multi-organ metastasis. Cancer antigen (CA) 125 (CA-125) and nine other blood indicators were found to show a significant, but weak correlation with multi-organ metastasis. A neural network cascade-multiple linear regression hybrid model was built to create an ovarian cancer metastasis index (OCMI) by integration of six multi-organ metastasis drivers including CA-125, blood platelet count, lymphocytes percentage, prealbumin, ascites, and laterality. In an independent set of 267 OC medical records, OCMI showed a moderate correlation with multi-organ metastasis (Spearman ρ = 0.67), the value being 0.72 in premenopausal patients, and good performance in identifying multi-organ metastasis (area under the receiver operating characteristic curve = 0.832), implying a potential prognostic marker for OC.

[Antibiotic resistance of Helicobacter pylori clinical isolates in Hebei Province].

OBJECTIVE: To evaluate the resistance of Helicobacter pylori (H.pylori) clinical isolates to various antibiotics, in order to guide rational drug use in Hebei Province. METHODS: From January 2014 to July 2015, 260 patients with H. pylori infection who had not received eradication treatment were enrolled in Third Hospital of Hebei Medical University. Gastric mucosa biopsy tissue samples were collected from these patients before treatment for isolation and culture of H. pylori. Kirby-Bauer method was used to detect drug-resistance rate of the H. pylori clinical isolates to metronidazole, clarithromycin, amoxicillin, levofloxacin, and furazolidone. RESULTS: A total of 155 H. pylori strains were isolated from tissue samples of the 260 patients (positive rate, 59.6%). The drug-resistance rate of H. pylori isolated to metronidazole, clarithromycin, amoxicillin, levofloxacin, and furazolidone was 94.2%(146/155), 21.3%(33/155), 2.6%(4/155), 5.8% (9/155), and 1.9%(3/155), respectively. There was no statistically significant difference in positive culture rate and drug-resistance rate between different sex, age, and disease category(all P>0.05). CONCLUSION: In Hebei Province, the resistance rates of H. pylori to metronidazole and clarithromycin appear to be higher than those to amoxicillin, levofloxacin, and furazolidone.