Identification and Validation of Common Reference Genes for Normalization of Esophageal Squamous Cell Carcinoma Gene Expression Profiles.

Esophageal squamous cell carcinoma (ESCC) is one of the subtypes of esophageal cancer with Chinese characteristics, and its five-year survival rate is less than 20%. Early diagnosis is beneficial to improving the survival rate of ESCC significantly. Quantitative Real-Time Polymerase Chain Reaction is a high-throughput technique that can quantify tumor-related genes for early diagnosis. Its accuracy largely depends on the stability of the reference gene. There is no systematic scientific basis to demonstrate which reference gene expression is stable in ESCC and no consensus on the selection of internal reference. Therefore, this research used four software programs (The comparative delta-Ct method, GeNorm, NormFinder, and BestKeeper) to evaluate the expression stability of eight candidate reference genes commonly used in other tumor tissues and generated a comprehensive analysis by RefFinder. Randomly selected transcriptome sequencing analysis confirmed the SPP1 gene is closely related to ESCC. It was found that the expression trend of SPP1 obtained by RPS18 and PPIA as internal reference genes were the same as that of sequencing. The results show that RPS18 and PPIA are stable reference genes, and PPIA + RPS18 are a suitable reference gene combination. This is a reference gene report that combines transcriptome sequencing analysis and only focuses on ESCC, which makes the quantification more precise, systematic, and standardized, and promotes gene regulation research and the early diagnosis of ESCC in the future.

Prognostic value of lncRNAs related to fatty acid metabolism in lung adenocarcinoma and their correlation with tumor microenvironment based on bioinformatics analysis.

Background: As a key regulator of metabolic pathways, long non-coding RNA (lncRNA) has received much attention for its relationship with reprogrammed fatty acid metabolism (FAM). This study aimed to investigate the role of the FAM-related lncRNAs in the prognostic management of patients with lung adenocarcinoma (LUAD) using bioinformatics analysis techniques. Methods: We obtained LUAD-related transcriptomic data and clinical information from The Cancer Genome Atlas (TCGA) database. The lncRNA risk models associated with FMA were constructed by single-sample gene set enrichment analysis (ssGSEA), weighted gene co-expression network (WGCNA), differential expression analysis, overlap analysis, and Cox regression analysis. Kaplan-Meier (K-M) and receiver operating characteristic (ROC) curves were utilized to assess the predictive validity of the risk model. Gene set variation analysis (GSVA) revealed molecular mechanisms associated with the risk model. ssGSEA and microenvironment cell populations-counter (MCP-counter) demonstrated the immune landscape of LUAD patients. The relationships between lncRNAs, miRNAs, and mRNAs were predicted by using LncBase v.2 and miRTarBase. The lncRNA-miRNA-mRNA regulatory network was visualized with Cytoscape v3.4.0. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was performed using DAVID v6.8. Quantitative real-time fluorescence PCR (qRT-PCR) was performed to verify the expression levels of the prognostic lncRNAs. Results: We identified 249 differentially expressed FMA-related lncRNAs in TCGA-LUAD, six of which were used to construct a risk model with appreciable predictive power. GSVA results suggested that the risk model may be involved in regulating fatty acid synthesis/metabolism, gene repair, and immune/inflammatory responses in the LUAD process. Immune landscape analysis demonstrated a lower abundance of immune cells in the high-risk group of patients associated with poor prognosis. Moreover, we predicted 279 competing endogenous RNA (ceRNA) mechanisms for 6 prognostic lncRNAs with 39 miRNAs and 201 mRNAs. Functional enrichment analysis indicated that the ceRNA network may be involved in the process of LUAD by participating in genomic transcription, influencing the cell cycle, and regulating tissue and organogenesis. In vitro experiments showed that prognostic lncRNA CTA-384D8.35, lncRNA RP5-1059L7.1, and lncRNA Z83851.4 were significantly upregulated in LUAD primary tumor tissues, while lncRNA RP11-401P9.4, lncRNA CTA-384D8.35, and lncRNA RP11-259K15.2 were expressed at higher levels in paraneoplastic tissues. Conclusion: In summary, the prognostic factors identified in this study can be used as potential biomarkers for clinical applications. ceRNA network construction provides a new vision for the study of LUAD pathogenesis.

RANK rs1805034 T>C Polymorphism Is Associated with Susceptibility to Gastric Cardia Adenocarcinoma in a Chinese Population.

BACKGROUND: Gastric cardia adenocarcinoma (GCA) is a common malignant tumor of the digestive tract with a high incidence in China. Genetic factors such as single nucleotide polymorphisms (SNPs) may contribute to the carcinogenesis of GCA. METHODS: We conducted a hospital-based case-control study to evaluate the genetic association of functional SNPs with susceptibility to GCA development. A total of 330 GCA cases and 608 controls were recruited for this study. The SNPs OPG rs3102735 T>C and rs2073618 G>C, RANK rs1805034 T>C, and RANKL rs9533156 T>C and rs2277438 A>G were determined using the ligation detection reaction method. RESULTS: Our findings suggest that RANK rs1805034 T>C is associated with susceptibility to GCA, which is more evident among male patients, elderly patients (≥ 60 years), smokers, and patients who do not consume alcohol. CONCLUSION: Based on our findings, the functional SNP RANK rs1805034 T>C may be an indicator for individual susceptibility to GCA. However, further larger studies with other ethnic populations and tissue-specific biological characterization are required to confirm the current findings.

The prominent expression of plasma matrix metalloproteinase-8 in acute thoracic aortic dissection.

BACKGROUND: The relationship between elastolytic matrix metalloproteinases (MMPs) (such as MMP-2, MMP-9) and thoracic aortic dissection (TAD) has been described, but little is known regarding the role of collagenolytic MMPs in thoracic aortic dissection. The aim of this study was to determine the role of MMP-8 in acute thoracic aortic dissection. MATERIALS AND METHODS: Forty-five patients affected by TAD and 40 with acute myocardial infarction (AMI) were recruited into this study. Blood samples within 72 h of the onset of symptoms were available for all the 85 patients. Healthy individuals were selected from the out-patients who complained of chest pain but in whom no cardiovascular diseases were found. Plasma levels of MMP-1, -8, -13 were measured by enzyme-linked immunosorbent assay (ELISA) technique in all subjects. Aortic tissue samples obtained during surgery were evaluated by Western blot for MMP-8 and tissue inhibitor of metalloproteinase-1 (TIMP-1) expression. RESULTS: Plasma MMP-8 levels in patients affected by TAD and AMI were both higher than that in healthy subjects (284.35 ± 96.32 ng/mL and 88.57 ± 26.71 ng/mL versus 75.39 ± 23.36 ng/mL). The difference of the MMP-8 level between TAD patients and healthy subjects was significant (P = 0.000). No significant differences were found in MMP-1 and MMP-13 plasma levels among the three groups. CONCLUSIONS: The acute phase of TAD is characterized by a prominent increase of MMP-8 plasma level, which may play a key role in the occurrence of TAD. MMP-8 could be involved in the acute inflammatory reaction and may be a useful marker for the diagnosis of acute TAD.