Cenococcum geophilum impedes cadmium toxicity in Pinus massoniana by modulating nitrogen metabolism.

Nitrogen (N) is of great significance to the absorption, distribution and detoxification of cadmium (Cd). Ectomycorrhizal fungi (EMF) are able to affect the key processes of plant N uptake to resist Cd stress, while the mechanism is still unclear. Therefore, we explored potential strategies of Cenococcum geophilum (C. geophilum) symbiosis to alleviate Cd stress in Pinus massoniana (P. massoniana) from the perspective of plant N metabolism and soil N transformation. The results showed that inoculation of C. geophilum significantly increased the activities of NR, NiR and GS in the shoots and roots of P. massoniana, thereby promoting the assimilation of NO3- and NH4+ into amino acids. Moreover, C. geophilum promoted soil urease and protease activities, but decreased soil NH4+ content, indicating that C. geophilum might increase plant uptake of soil inorganic N. qRT-PCR results showed that C3 symbiosis significantly up-regulated the expression of genes encoding functions involved in NH4+ uptake (AMT3;1), NO3- uptake (NRT2.1, NRT2.4, NRT2.9), as well as Cd resistance (ABCC1 and ABCC2), meanwhile down-regulated the expression of NRT7.3, Cd transporter genes (HMA2 and NRAMP3) in the roots of P. massoniana seedlings. These results demonstrated that C. geophilum was able to alleviate Cd stress by increasing the absorption and assimilation of inorganic N in plants and inhibiting the transport of Cd from roots to shoots, which provided new insights into how EMF improved host resistance to abiotic stress.

Sensitive electrochemical biosensor for rapid detection of sEV-miRNA based turbo-like localized catalytic hairpin assembly.

Small extracellular vesicle-associated microRNAs (sEV-miRNAs) have emerged as critical biomarkers for cancer diagnosis, yet the rapid detection of these low-abundance molecules in clinical samples remains a formidable challenge. Herein, a simple turbo-like localized catalytic hairpin assembly (TL-CHA) was proposed for sEV-miR-1246 measurement. This electrochemical sensor achieves dual localization through the ingeniously use of AuNPs and DNA nanowires, which provides rich sites for CHA cascade amplification, significantly enhancing the effective reaction and amplify the detection response. Leveraging this innovative design, this biosensor demonstrated the ability to detect sEV-miRNA at concentrations as low as 5.24 aM in a time frame of 30 min. The precision of the measurements was validated through reverse transcription quantitative polymerase chain reaction. Furthermore, the sensor was used for analyzing plasma samples from gastric cancer patients yielded AUC values of 0.973 for all stages and 0.945 for early stages. This demonstrates the sensor's robust performance in both the staging diagnosis and early screening of gastric cancer. Therefore, this platform has great potential for the clinical cancer diagnosis.

The Transcriptional Responses of Ectomycorrhizal Fungus, Cenococcum geophilum, to Drought Stress.

With global warming, drought has become one of the major environmental pressures that threaten the development of global agricultural and forestry production. Cenococcum geophilum (C. geophilum) is one of the most common ectomycorrhizal fungi in nature, which can form mycorrhiza with a large variety of host trees of more than 200 tree species from 40 genera of both angiosperms and gymnosperms. In this study, six C. geophilum strains with different drought tolerance were selected to analyze their molecular responses to drought stress with treatment of 10% polyethylene glycol. Our results showed that drought-sensitive strains absorbed Na and K ions to regulate osmotic pressure and up-regulated peroxisome pathway genes to promote the activity of antioxidant enzymes to alleviate drought stress. However, drought-tolerant strains responded to drought stress by up-regulating the functional genes involved in the ubiquinone and other terpenoid-quinone biosynthesis and sphingolipid metabolism pathways. The results provided a foundation for studying the mechanism of C. geophilum response to drought stress.

Comparative Physiological and Transcriptome Analysis Provide Insights into the Response of Cenococcum geophilum, an Ectomycorrhizal Fungus to Cadmium Stress.

Cadmium (Cd) displays strong toxicity, high mobility, and cannot be degraded, which poses a serious threat to the environment. Cenococcum geophilum (C. geophilum) is one of the most common ectomycorrhizal fungi (ECMF) in the natural environment. In this study, three Cd sensitive and three Cd tolerant strains of C. geophilum were used to analyze the physiological and molecular responses to Cd exposure. The results showed that Cd inhibited the growth of all strains of C. geophilum but had a less toxic effect on the tolerant strains, which may be correlated to a lower content of Cd and higher activity of antioxidant enzymes in the mycelia of tolerant strains. Comparative transcriptomic analysis was used to identify differentially expressed genes (DEGs) of four selected C. geophilum strains after 2 mg/L Cd treatment. The results showed that the defense response of C. geophilum strain to Cd may be closely related to the differential expression of functional genes involved in cell membrane ion transport, macromolecular compound metabolism, and redox pathways. The results were further confirmed by RT-qPCR analysis. Collectively, this study provides useful information for elucidation of the Cd tolerance mechanism of ECMF.

High Expression of MDM2 and the p53 Protein is Predictive Biomarkers for Poor Prognosis of Oesophageal Squamous Cell Carcinoma.

BACKGROUND AND OBJECTIVE: In the present study, we detected the expression of MDM2 and p53 in oesophageal squamous cell carcinoma (OSCC) specimens, studied their relationship with the survival of OSCC patients, and explored the potential of MDM2 and p53 to serve as predictive OSCC tumour markers. PATIENTS AND METHODS: Through immunohistochemistry and fluorescence in situ hybridization (FISH), we detected the expression of MDM2 and the p53 protein in 157 OSCC specimens that met the inclusion and exclusion criteria. After scoring the results, Pearson's chi-square test and Cox regression were used for analysis. RESULTS: The results showed that the rates of high MDM2 and p53 expression in OSCC tissues were 60.5% and 51.0%, respectively. The expression levels of MDM2 and p53 in OSCC were significantly positively correlated (p<0.001, r=0.414). In addition, the pathological metastasis (M) status and MDM2 protein expression in OSCC were significantly correlated (p=0.027), and high expression of the p53 protein was positively correlated with OSCC transfer (p=0.005), pathological node status (p=0.008), and clinical stage (p=0.003). Kaplan-Meier survival analysis showed that the high expression of MDM2 and p53 was significantly related to the poor prognosis of OSCC. Moreover, subgroup analysis of the TNM staging of OSCC patients showed that the high expression of MDM2 and p53 was significantly correlated with poor OS and DFS of OSCC patients in either stage I-II or III-IV patients. Both univariate and Cox multivariate analyses showed that p53 and MDM2 can be used as independent factors for the prognosis of OSCC patients. Finally, our FISH detection results for MDM2 showed that the high expression of MDM2 was significantly correlated with the amplification of MDM2 (p=0.015). CONCLUSION: This study shows that MDM2 and p53 can be used as independent predictors of the prognosis of patients with oesophageal squamous cell carcinoma.

Long noncoding RNA CASC11 promotes hepatocarcinogenesis and HCC progression through EIF4A3-mediated E2F1 activation.

BACKGROUND: Growing evidences have been revealing that long noncoding RNAs are vital factors in oncogenesis and tumor development. Among them, cancer susceptibility candidate 11 (CASC11) has displayed an impressively essential role in various kinds of cancers including hepatocellular carcinoma (HCC). Nevertheless, its role and potential mechanism in HCC still remain to be fully investigated. METHODS: CASC11 expression level was evaluated by real-time polymerase chain reaction, western blotting, and in situ hybridization staining in HCC patients, and its prognostic effect was analyzed. The role of CASC11 in HCC tumorigenesis and progression was investigated by cell proliferation assay, transwell assay, extracellular acidification rate, western blotting, flow cytometry, and an in vivo xenograft model. The interactions among CASC11, E2F transcription factor 1 (E2F1), and eukaryotic translation initiation factor 4A3 (EIF4A3) were explored by using quantitative reverse transcriptase polymerase chain reaction, western blotting, RNA-binding protein immunoprecipitation assay, and chromatin immunoprecipitation assays. RESULTS: Upregulation of CASC11 was confirmed in HCC tissues and associated with poor prognosis. Loss of function assays showed inhibition of CASC11 expression suppressed HCC cells proliferation, mobility, and glucose metabolism and promoted apoptosis. E2F1 expression significantly decreased after inhibition of CASC11. Rescue experiments illustrated that E2F1 overexpression alleviated the suppression of CASC11 inhibition on HCC progression in vitro and in vivo. Mechanistically, CASC11 recruited EIF4A3 to enhance the stability of E2F1 mRNA. CASC11 and E2F1 impacted the activation of the NF-κB signaling and PI3K/AKT/mTOR pathway and further regulated the expression PD-L1 that is an important target of immunotherapy. In addition, we identified YY1 could modulate CASC11 expression by binding to its promoter. CONCLUSIONS: Our data revealed that CASC11 promoted the progression of HCC by means of EIF4A3-mediated E2F1 upregulation, indicating CASC11 is a promising diagnostic biomarker and therapeutic target for HCC.

Identification of three predictors of gastric cancer progression and prognosis.

Abnormal gene expression is an established cause of gastric cancer (GC) initiation and progression. In this study, we aimed to identify several key genes that could be used to effectively predict progression and prognosis in patients with GC. The Cancer Genome Atlas and the Gene Expression Omnibus database were used to identify candidate genes. Fourteen genes were found to associate highly with progress, metastasis, and survival of GC. Five of these genes were overexpressed in tumor tissue compared to adjacent normal tissue. This was confirmed by reverse transcription-polymerase chain reaction and western blotting for myosin-Va (MYO5A), phospholipid transfer protein (PLTP), and tripeptidyl peptidase 1 (TPP1), while the CCK8 assay was used to show that these three genes promote GC cell proliferation. In summary, we demonstrate that MYO5A, PLTP, and TPP1 expression may be suitable markers for the progression and prognosis of GC.