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.

Dioscin Impedes Proliferation, Metastasis and Enhances Autophagy of Gastric Cancer Cells via Regulating the USP8/TGM2 Pathway.

Gastric cancer (GC) is one of the most common cancers worldwide. Dioscin has been shown to have anti-cancer effects in GC. The aim of this study is to explore a novel mechanism of dioscin in repressing GC progression. Cell viability, proliferation, apoptosis and invasion were measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry and transwell assays, respectively. Monodansylcadaverine (MDC) staining was used to assess cell autophagy. The expression of transglutaminase-2 (TGM2), ubiquitin-specific peptidase 8 (USP8) and autophagy-related proteins was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. A xenograft tumor model was established to investigate the function of dioscin in vivo. Dioscin inhibited GC cell proliferation and invasion, but induced apoptosis and autophagy. TGM2 was highly expressed in GC, and dioscin suppressed GC progression by decreasing the protein level of TGM2. Furthermore, USP8 positively regulated TGM2 expression, and TGM2 overexpression reversed the inhibitory effect of USP8 knockdown on GC cell progression. USP8 abated the effect of dioscin in GC cells. Dioscin decreased the protein level of TGM2 via regulating USP8. In addition, dioscin restrained GC tumor growth in vivo. Dioscin played an anti-cancer effect in GC by enhancing cancer cell autophagy via regulating the USP8/TGM2 pathway.

Bisphenol A Promotes the Progression of Colon Cancer Through Dual-Targeting of NADPH Oxidase and Mitochondrial Electron-Transport Chain to Produce ROS and Activating HIF-1α/VEGF/PI3K/AKT Axis.

Bisphenol A (BPA) is a high-production-volume industrial chemical. Despite recent research conducted on its carcinogenicity, its role in the development of colon cancer (CC) has been rarely studied. This study aims to evaluate the effects of BPA on the migration and invasion of CC cells. First, we clinically verified that patients with CC exhibit higher serum BPA level than healthy donors. Subsequently, different CC cell lines were exposed to a series of BPA concentrations, and the migration and invasion of cells were detected by the wound healing test and transwell assay. Finally, N-acetyl-L-cysteine (NAC) and siHIF-1α intervention was used to explore the effects of ROS and HIF-1α on cell migration and invasion, respectively. The results demonstrated that the occurrence of BPA-induced migration and invasion were dependent on the dose and time and was most pronounced in DLD1 cells. ROS production was jointly driven by NADPH oxidase (NOX) and mitochondrial electron-transport chain (ETC). Furthermore, the intervention of NAC and siHIF-1α blocked the HIF-1α/VEGF/PI3K/AKT axis and inhibited cell migration and invasion. In conclusion, our results suggest that BPA exposure promotes the excessive production of ROS induced by NOX and ETC, which in turn activates the HIF-1α/VEGF/PI3K/AKT axis to promote the migration and invasion of CC cells. This study provides new insights into the carcinogenic effects of BPA on CC and warns people to pay attention to environmental pollution and the harm caused to human health by low-dose BPA.

Dihydroartemisinin mediating PKM2-caspase-8/3-GSDME axis for pyroptosis in esophageal squamous cell carcinoma.

Pyroptosis is a novel type of pro-inflammatory programmed cell death that has been strongly reported to be related to inflammation, immune, and cancer. Dihydroartemisinin (DHA) has good anti-tumor properties. However, the exact mechanism by which DHA induces pyroptosis to inhibit esophageal squamous cell carcinoma (ESCC) remains unclear. After applying DHA treatment to ESCC, we found that some dying cells exhibited the characteristic morphology of pyroptosis, such as blowing large bubbles from the cell membrane, accompanied by downregulation of pyruvate kinase isoform M2 (PKM2), activation of caspase-8/3, and production of GSDME-NT. Meanwhile, it was accompanied by an increased release of LDH and inflammatory factors (IL-18 and IL-1ß). Both knockdown of GSDME and application of caspase-8/3 specific inhibitors (z-ITED-FMK/Ac-DEVD-CHO) significantly inhibited DHA-induced pyroptosis. However, the former did not affect the activation of caspase-3. In contrast, overexpression of PKM2 inhibited caspase-8/3 activation as well as GSDME-N production. Furthermore, both si-GSDME and OE-PKM2 inhibited DHA-induced pyroptosis in vivo and in vitro. Therefore, the results suggest that DHA can induce pyroptosis of ESCC cells via the PKM2-caspase-8/3-GSDME pathway. Implication: In this study, we identified new mechanism of DHA in inhibiting ESCC development and progression, and provide a potential therapeutic agent for the treatment of ESCC.

Identification of sixteen metabolic genes as potential biomarkers for colon adenocarcinoma.

PURPOSE: To identify some key prognosis-related metabolic genes (PRMG) and establish a clinical prognosis model for colon adenocarcinoma (COAD) patients. METHODS: We used The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) to obtain gene expression profiles of COAD, and then identified differentially expressed prognostic-related metabolic genes through R language and Perl software, Through univariate Cox analysis and least absolute shrinkage and selection operator (LASSO) Cox analysis to obtain target genes, established metabolic genes prognostic models and risk scores. Through Cox regression analysis, independent risk factors affecting the prognosis of COAD were analyzed, and receiver operating characteristics (ROC) curve analysis of independent prognostic factors was performed and a nomogram for predicting overall survival was constructed. We performed the consistency index (C-index) test and decision curve analysis (DCA) on the nomogram, and used gene set enrichment analysis (GSEA) to identify the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway of model genes. We selected PRMG based on the expression of metabolic genes, and used LASSO Cox regression to construct 16 metabolic gene models (SEPHS1, P4HA1, ENPP2, PTGDS, GPX3, CP, ASPA, POLR3A, PKM, POLR2D , XDH, EPHX2, ADH1B, HMGCL, GPD1L and MAOA). RESULTS: The risk score generated from our model can well predict the survival prognosis of COAD. A nomogram based on the clinicopathological characteristics and risk scores of COAD can personally predict the overall survival rate of COAD patients. CONCLUSIONS: The risk score based on the expression of 16 metabolic genes can effectively predict the prognosis of patients with COAD.

eEF2K as a novel metastatic and prognostic biomarker in gastric cancer patients.

BACKGROUND: Although eukaryotic elongation factor 2 kinase (eEF2K) has been reported to be a potential oncogenic factor in many human cancers, its usefulness as a clinical prognostic biomarker for gastric cancer has not been investigated. METHODS: In this study, data about 540 patients with stomach adenocarcinoma (STAD) were analyzed from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases to determine the expression of eEF2K. Immunohistochemistry (IHC), western blots, and real-time polymerase chain reaction (RT-PCR) were also performed to determine the clinical significance of eEF2K expression in 96 postoperative patients with gastric cancer. Among the 96 patients, 36 had low expression of eEF2K and 60 had high expression. RESULTS: Analysis of the TCGA and GEO datasets revealed that eEF2K expression was significantly higher in the STAD tissue samples than in the non-tumorous gastric tissues. IHC, western blots, and RT-PCR confirmed these findings. The high expression level of eEF2K was found to be related to the presence of lymph node metastasis (p = 0.002). Moreover, multivariate analysis showed that eEF2K was an independent indicator of prognosis for overall survival (OS) (hazard ratio [HR] = 1.72, 95% confidence interval [CI] = 1.06-2.79; p = 0.03) and disease-free survival (DFS) (HR = 1.66, 95% CI = 0.997-2.765; p = 0.052) in patients with surgically resected STAD. CONCLUSION: Collectively, our findings suggest that eEF2K is a clinical indicator of metastatic and prognostic significance for STAD survival and could serve as a potential therapeutic target.

SPNS2 promotes the malignancy of colorectal cancer cells via regulating Akt and ERK pathway.

Colorectal cancer (CRC) is a prevalent malignant tumour that causes considerable cancer-related deaths globally. The sphingolipid transporter 2 (SPNS2), a sphingosine-1-phosphate (S1P) transporter, modulates multiple biological events including malignancy of cancer cells. In this study, the effects of SPNS2 on CRC progression were studied. We found that SPNS2 expression was significantly upregulated in CRC tissues compared to that in adjacent non-tumour tissues. To assess the role of SPNS2 in CRC cells, we performed loss- and gain-of-function experiments in SW480 and HCT116 cells, respectively. The results demonstrated that SPNS2 promoted proliferation, migration and invasion, and inhibited apoptosis in CRC cells. Additionally, SPNS2 enhanced the release of intracellular S1P, and increased S1P receptor 1 (S1PR1) and S1PR3 expression. Moreover, SPNS2 activated the Akt and ERK pathways, and the biological behaviours of SPNS2 were attenuated by Akt or ERK inhibitor in HCT116 cells. In conclusion, our results demonstrated that SPNS2 promoted proliferation, migration and invasion, and inhibited apoptosis by regulating S1P/S1PR1/3 axis and activating Akt and ERK pathway in CRC cells.

A novel and safe approach: middle cranial approach for laparoscopic right hemicolon cancer surgery with complete mesocolic excision.

BACKGROUND: Mastering right hemicolectomy techniques using laparoscopy in colorectal cancer surgery is very difficult. Although the long-term prognosis of laparoscopic right hemicolectomy (LRH) and complete mesocolic excision is unquestionable, different surgeons have their own opinions on routes of conducting LRH. OBJECTIVES: LRH surgery is very complex due to the upper abdominal anatomical structure and vascular variation. Therefore, it has been considered the most difficult of all colorectal cancer surgeries. Our innovative middle cranial approach (MCA) was developed to avoid unnecessary injuries and minimize the operative time, thereby reducing the patient's hospital stay and improving their short-term prognosis. METHODS: We compared 90 colon cancer patients who underwent the MCA between January 2016 and January 2017 with 82 patients who underwent the conventional central approach conducted by the same group of physicians (with Dr Cui as the surgeon) from 2011 to 2015. A short-term statistical analysis was performed. RESULTS: A total of 90 patients were included: 43 men and 47 women. Twenty-three patients underwent abdominal surgery (including stomach, rectum, and sigmoid colon surgery; appendectomy; and uterine attachment surgery). The median age of these patients was 62.6 (28-85) years; the median BMI was 22.9 (14.7-33.3) kg/m2; the mean bleeding volume was 53.9 (10-100) ml; the mean tumour diameter was 5.7 (0.8-9) cm, and the average number of lymph nodes detected was 19.2 (7-49). CONCLUSIONS: Our study showed that radical resection of right-sided colon cancer using the MCA was safe and feasible for the treatment of colorectal cancer patients.