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Abstract Metabolic reprogramming is one of the hallmarks of cancer. As nutrients are scarce in the tumor microenvironment (TME), tumor cells adopt multiple metabolic adaptations to meet their growth requirements. Metabolic reprogramming is not only present in tumor cells, but exosomal cargos mediates intercellular communication between tumor cells and non-tumor cells in the TME, inducing metabolic remodeling to create an outpost of microvascular enrichment and immune escape. Here, we highlight the composition and characteristics of TME, meanwhile summarize the components of exosomal cargos and their corresponding sorting mode. Functionally, these exosomal cargos-mediated metabolic reprogramming improves the "soil" for tumor growth and metastasis. Moreover, we discuss the abnormal tumor metabolism targeted by exosomal cargos and its potential antitumor therapy. In conclusion, this review updates the current role of exosomal cargos in TME metabolic reprogramming and enriches the future application scenarios of exosomes.

The aim of this study was to investigate whether and how exosomal miR-205-5p regulated angiogenesis and nasopharyngeal carcinoma (NPC) metastasis. We found that up-regulated serum exosomal miR-205-5p levels were associated with NPC progression and worse overall survival of NPC patients. miR-205-5p over-expression significantly increased tube formation, wound healing, migration and invasion of NPC cells, and lung metastasis of NPC tumors, whereas miR-205-5p inhibition had opposite effects. Exosomal miR-205-5p from NPC cells promoted the migration, tube formation, and microvessel density (MVD) of HUVECs in vitro and in vivo. Furthermore, bioinformatics-, luciferase reporter-, and biotinylated miR-205-5p-based pull-down assays indicated that miR-205-5p directly bound to the 3′ UTR of desmocollin-2 (DSC2). Exosomal miR-205-5p targeted DSC2 to enhance the EGFR/ERK signaling and MMP2/MMP9 expression, promoting angiogenesis and NPC metastasis, which was abrogated by DSC2 over-expression. Finally, the levels of miR-205-5p transcripts were positively correlated with MVD but negatively with DSC2 expression in NPC tissues, and patients with miR-205high/DSC2low NPC had worse overall survival. In conclusion, exosomal miR-205-5p promotes angiogenesis and NPC metastasis by targeting DSC2 to enhance EGFR/ERK signaling and MMP expression. This exosomal/miR-205-5p/EGFR/ERK axis may be a new therapeutic target for intervention of NPC metastasis.

Tripartite motif-containing 28 (TRIM28) belongs to tripartite motif (TRIM) family. TRIM28 not only binds and degrades its downstream target, but also acts as a transcription co-factor to inhibit gene expression. More and more studies have shown that TRIM28 plays a vital role in tumor genesis and progression. Here, we reviewed the role of TRIM28 in tumor proliferation, migration, invasion and cell death. Moreover, we also summarized the important role of TRIM28 in tumor stemness sustainability and immune regulation. Because of the importance of TRIM28 in tumors, TIRM28 may be a candidate target for anti-tumor therapy and play an important role in tumor diagnosis and treatment in the future.

Nowadays, e-learning is widely adopted in all education sectors, but different teachers utilize different strategies to teach their students. In the field of teacher education, views on the ways in which e-learning can be used are also varied. It is worth exploring how to implement e-learning in courses and how student teachers can apply the e-learning strategies they learned during their own field experience courses. A better understanding of the current practice will not only help teacher educators and student teachers to understand relevant pedagogical approaches in regard to e-learning, but will also enable student teachers to learn how to use appropriate e-learning strategies in their classes. This study explores the e-learning strategies adopted in teacher education courses for pre-service English teachers in mainland China, with a focus on Chinese fourth-tier cities. A total of 475 student teachers were involved and a mixed-method research approach was adopted. Both qualitative and quantitative data were collected via questionnaires and interviews. The findings can enhance the current understanding of the common strategies used in e-learning in English pre-service teacher education courses in Chinese fourth-tier cities. We also give some suggestions for better future e-learning pedagogical approaches.

In this study, three design cycles have been conducted in three different courses taught by the research team members at the Education University of Hong Kong. The duration of the research spanned two years and all courses were ICT related. In the first case, we focused on how to implement the flipped classroom in the lesson while in the second and third cases, we put more emphasis on the technology issues and assessment strategies in a flipped classroom. The findings show that the flipped classroom approach can be applied to courses in higher education settings. In ICT related courses, the technology issue is not a problem as the technical hurdle is low and the course lecturers should be more ICT educated. Thus, we can implement this approach in courses focused on learning ICT, learning to teach with ICT or learning to teach ICT.

Technological development has promoted the implementation of e-learning in teaching and learning. E-learning practices inspire student-teachers to design their lessons using various approaches. Thus, examining these practices has become vital in teacher education. To achieve practical outcomes, ways to improve English teachers' training program through e-learning has led to a widespread discussion in China. This study aims to identify the contributions of e-learning and determine the processes of its practices in English teacher education. Previous studies have revealed scarce relevant research and have indicated that e-learning tools are not commonly used in fourth-tier Chinese cities compared with other developed Chinese cities. Therefore, this exploratory study focuses on the e-learning practices in English teacher education in fourth-tier Chinese cities. The mixed-method approach is adopted in the research, and the TPACK Model is utilized for the research instrument design. In addition, a total of 150 participants are involved in this study. The findings will help teacher educators and student-teachers to understand the implementation processes of e-learning in fourth-tier cities within the technological pedagogical content knowledge framework. At the same time, a clear picture of the merits and flaws of the current e-learning practices in English teacher education is visualized. Furthermore, this study suggests the future functions of e-learning in English teacher education in fourth-tier Chinese cities. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau is a vast, elevated plateau in Central Asia with an average elevation of over 4,500 m and contains the world’s third largest store of ice. It occupies a climatic transition zone between the Asian monsoons and westerly airflow. As a result of this location, the region is sensitive to changes in climate on timescales of decades to millennia and longer. Long-term data are needed to evaluate climatic changes and their impact on ecosystems, but in areas as remote as the Tibetan Plateau, long-term instrumental records of environmental change are geographically sparse and monitoring has only been undertaken in recent times. Paleolimnological approach might be then one of the few means by which environmental variability can be ascertained at scales that allow comparison with contemporary monitoring data and future model projections. Therefore, a paleolimnological study was undertaken in eight different lakes sampled along a North–South transect across the Tibetan Plateau analysing geochemistry and algal pigment in order to assess longer term variability in the trophic condition of these systems and their potential to reconstruct changes in relation to recent climate evolution and possible human impacts. Chronologies for the last century were based on radiometric techniques (210Pb, 241Am and 137Cs). Results show that inorganic sediment dominates the composition of the cores used in this study. Organic carbon constitutes less than 5% d.w. in all the lake cores, except for Kemen Co core where concentrations up to 14% d.w., are observed. Corg:N ratios are generally in the order of 5–10, indicating that autochthonous algal production is the principal biological source of organic matter. Pigment preservation is generally good throughout the cores from all lakes as shown by the 430:410 nm ratio that is generally around 1.0 or higher. Six out of eight lakes show an increase in primary production in recent times. High pre-1800 AD pigment concentrations were detected only in Qinghai Lake. Since most of the lakes show a similar behaviour in the most recent section of the core, we interpret this as a response to climate and land-use changes that have increased autochthonous production throughout the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Large oil fields are distributed within the loess plateau of northwest China, where severe soil contamination by petroleum hydrocarbons has been found in several locations. A prevention measure is to modify the topsoils with surfactants to enhance the attenuation capacity in the vadose zone. In this paper, both cationic surfactant hexadecyltrim–ethylammonium bromide (HDTMA-Br) and anionic surfactant—sodium dodethylbenzene sulfonate were used to modify the natural loess soils. The sorption of organic contaminants in the modified soils can be characterized by linear isotherms. By using toluene as an indicator of petroleum hydrocarbons, partition and adsorption contributions to the sorption amount were determined quantitatively. The approach displayed enhanced soil sorption capabilities by 2–10 times. Column tests showed that the retardation capacity of the HDTMA-modified soil for p-nitroaniline solution increased the breakthrough time at least three times as compared to the natural loess soil. Using the suggested surfactants would significantly enhance the topsoil’s ability to delay transport of petroleum leachates. [ABSTRACT FROM AUTHOR]