Search

Simple Summary: Colorectal cancer (CRC) is one of the most common cancers, which has a poor prognosis and is prone to recurrence and metastasis. DPP7 is a prolyl peptidase, which is an enzyme characterized by the feature of cleaving proline-containing peptides. We found that the expression level of DPP7 in CRC samples was significantly higher than that in adjacent non-tumor tissues by analyzing public colorectal cancer data and surgical specimens of CRC patients. Moreover, the increased expression of DPP7 is correlated with a higher stage of cancer and shorter overall survival, indicating the diagnostic value of DPP7 for CRC. Furthermore, functional annotations indicated that DPP7 is involved in neuroactive ligand–receptor interaction and olfactory transduction signaling. Our data demonstrated that DPP7 is a promising diagnostic and prognostic biomarker as well as a new therapeutic target for CRC. Colorectal cancer has a poor prognosis and is prone to recurrence and metastasis. DPP7, a prolyl peptidase, is reported to regulate lymphocyte quiescence. However, the correlation of DPP7 with prognosis in CRC remains unclear. With publicly available cohorts, the Wilcoxon rank-sum test and logistic regression were employed to analyze the relationship between DPP7 expression and the clinicopathological features of CRC patients. Specific pathways of differentially expressed genes were determined through biofunctional analysis and gene set enrichment analysis (GSEA). qPCR and immunohistochemical staining were used to determine DPP7 expression levels in surgical specimens. The public dataset and analysis of the biospecimens of CRC patients revealed that DPP7, in the CRC samples, was expressed significantly higher than in non-tumor tissues. Moreover, increased DPP7 was significantly associated with a higher N stage, lymphatic invasion, and shorter overall survival. Functionally, DPP7 is involved in neuroactive ligand–receptor interaction and olfactory transduction signaling. We identified a series of targeted drugs and small-molecule drugs with responses to DPP7. To conclude, DPP7 is a valuable diagnostic and prognostic biomarker for CRC and considered as a new therapeutic target. [ABSTRACT FROM AUTHOR]

The upper-level jet stream, a narrow band of maximum wind speed in the mid-latitude westerlies, exerts a considerable influence on the global climate by modulating the transport and distribution of momentum, heat and moisture. In this study by using four high-resolution models in the Paleoclimate Modelling Intercomparison Project phase 3, the changes of position and intensity of the northern hemisphere westerly jet at 200 hPa in summer during the mid-Holocene (MH), as well as the related mechanisms, are investigated. The four models show similar performance on the westerly jet. At the hemispheric scale, the simulated westerly jet has a poleward shift during the MH compared to the preindustrial period. The warming in arctic and cooling in the tropics during the MH are caused by the orbital changes of the earth and the precipitation changes, and it could lead to the weakened meridional temperature gradient and pressure gradient, which might account for the poleward shift of the westerly jet from the thermodynamic perspective. From the dynamic perspective, two maximum centers of eddy kinetic energy are simulated over the North Pacific and North Atlantic with the north deviation, which could cause the northward movement of the westerly jet. The weakening of the jet stream is associated with the change of the Hadley cell and the meridional temperature gradient. The largest weakening is over the Pacific Ocean where both the dynamic and the thermodynamic processes have weakening effects. The smallest weakening is over the Atlantic Ocean, and it is induced by the offset effects of dynamic processes and thermodynamic processes. The weakening over the Eurasia is mainly caused by the dynamic processes. [ABSTRACT FROM AUTHOR]