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101.
At present, growing evidence indicates that long non‐coding RNAs (lncRNAs) participate in the progression of glioma. The function of LOXL1AS1 in vasculogenic mimicry (VM) in glioma remains unclear. First, the expressions of TIAR, the lncRNA LOXL1AS1, miR374b5p and MMP14 were examined by qRT‐PCR and Western blot in both, glioma tissues and glioma cell lines. Proliferation, migration, invasion and tube formation assays were conducted to evaluate the roles of TIAR, LOXL1AS1, miR374b5p and MMP14 in malignant cellular behaviours in glioma cells. A nude mouse xenograft model and dual staining for CD34 and PAS were used to assess whether VM was affected by TIAR, LOXL1AS1 or miR374b5p in vivo. In this study, low levels of TIAR and high levels of LOXL1AS1 were found in glioma cells and tissues. TIAR downregulated the expression of LOXL1AS1 by destabilizing it. LOXL1AS1 acted like a miRNA sponge towards miR374b5p so that downregulation of the former greatly inhibited cell proliferation, migration, invasion and VM. Additionally, miR374b5p overexpression repressed malignant biological behaviours and VM in glioma by modifying MMP14. In summary, we demonstrated that TIAR combined with LOXL1AS1 modulates VM in glioma via the miR374b5p/MMP14 axis, revealing novel targets for glioma therapy.  相似文献   
102.
Although several altered metabolic genes have been identified to be involved in the tumorigenesis and advance of pancreatic cancer (PC), their prognostic values remained unclear. The purpose of this study was to explore new targets and establish a metabolic signature to predict prognosis and chemotherapy response for optimal individualized treatment. The expression data of PC patients from two independent cohorts and metabolism-related genes from KEGG were utilized and analyzed for the establishment of the signature via lasso regression. Then, the differentially expressed candidate genes were further confirmed via online data mining platform and qRT-PCR of clinical specimens. Then, the analyses of gene set enrichment, mutation, and chemotherapeutic response were performed via R package. As results showed, 109 differentially expressed metabolic genes were screened out in PC. Then a metabolism-related five-gene signature comprising B3GNT3, BCAT1, KYNU, LDHA, and TYMS was constructed and showed excellent ability for predicting survival. A novel nomogram coordinating the metabolic signature and other independent prognostic parameters was developed and showed better predictive power in predicting survival. In addition, this metabolic signature was significantly involved in the activation of multiple oncological pathways and regulation of the tumor immune microenvironment. The patients with high risk scores had higher tumor mutation burdens and were prone to be more sensitive to chemotherapy. In summary, our work identified a new metabolic signature and established a superior prognostic nomogram which may supply more indications to explore novel strategies for diagnosis and treatment.  相似文献   
103.
104.
Tumor necrosis factor-α-induced protein 8 (TNFAIP8 or TIPE) is a member of the TNFAIP8 family. While TIPE was broadly considered to be pro-cancerous, its precise roles in carcinogenesis especially those of the intestinal tract are not clear. Here, we show that genetic deletion of TIPE in mice exacerbated chemical-induced colitis and colitis-associated colon cancer. Loss of TIPE exacerbated inflammatory responses and inflammation-associated dysbiosis, leading to the activation of NF-κB and STAT3, and it also accelerated dysplasia, DNA damage and proliferation of intestinal epithelial cells. We further show that colon microbiota were essential for increased tumor growth and progression in Tipe−/− mice. The tumor suppressive function of TIPE originated primarily from the non-hematopoietic compartment. Importantly, TIPE was downregulated in human colorectal cancers, and patients with low levels of Tipe mRNA were associated with reduced survival. These results indicate that TIPE serves as an important modulator of colitis and colitis-associated colon cancer.Subject terms: Cancer microenvironment, Chronic inflammation  相似文献   
105.
Tumor necrosis factor α stimulated gene 6 (TSG-6), a 30-KD secretory protein, plays an essential role in modulating inflammatory responses and extracellular matrix remodeling. However, little is known regarding the role of TSG-6 in human cancers. Here, we investigated the mechanism of action and the role of TSG-6 in colorectal cancer (CRC) metastasis. We found that TSG-6 was highly expressed in tumor tissues and was associated with poor prognosis and metastasis in CRC. Mechanistically, TSG-6 overexpression in CRC cells resulted in ERK activation and epithelial-mesenchymal transition by means of stabilizing CD44 and facilitating the CD44-EGFR complex formation on the cell membrane. Consequently, this resulted in the promotion of tumor migration and invasion both in vitro and in vivo. Notably, our data showed that CRC cells secreted TSG-6 could trigger a paracrine activation of JAK2-STAT3 signaling and reprogram normal fibroblasts into cancer-associated fibroblasts, which exhibited upregulation of pro-metastatic cytokines (CCL5 and MMP3) and higher movement ability. In animal models, the co-injection of cancer cells and TSG6-reprogrammed fibroblasts led to a significant increase in tumor metastasis. Our findings indicated that TSG-6 overexpression in CRC cells could promote cancer metastasis in both an autocrine and paracrine manner. Therefore, targeting TSG-6 might be a potential therapeutic strategy for the treatment of metastatic CRC.  相似文献   
106.
正Dear Editor.Transmembrane proteins withβ-barrel topology are mainly found in the outer membranes (OMs) of Gram-negative bacteria,mitochondria and chloroplasts (Wimley,2003).These proteins usually contain even numbers ofβ-strands,ranging from 8-36.To achieve an overall cylindrical topology,the polypeptide chain of aβ-barrel OMP must fold to form a series of anti-parallelβ-strands with eachβ-strand hydrogen-bonding to its neighboring strands (Otzen and Andersen,2013).The folding and insertion of aβ-barrel OMP in vivo requires an evolutionarily conserved multiprotein complex termedβ-barrel assembly machinery(BAM) complex (Noinaj et al.,2015).The structures of the  相似文献   
107.
Y Tang  F Lou  J Wang  Y Li  S Zhuang 《Phytochemistry》2001,58(8):1251-1256
Two coumaroyl flavonol glycosides, isorhamnetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], and kaempferol 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside]-7-O-beta-D-glucopyranoside, were isolated from the n-BuOH extract of Ginkgo biloba leaves. These two, together with six other flavonol glycosides, kaempferol 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], quercetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], quercetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside]-7-O-beta-D-glucopyranoside, quercetin 3-O-beta-D-glucopyranosyl-(1-2)-alpha-L-rhamnopyranoside, quercetin 3-O-beta-rutinoside, and quercetin 3-O-beta-D-glucopyranoside, showed profound antioxidant activities in DPPH and cytochrome-c reduction assays using the HL-60 cell culture system.  相似文献   
108.
The worldwide geographic and ethnic clustering of patients with diseases related to human T-cell lymphotropic virus type I (HTLV-I) may be explained by the natural history of HTLV-I infection. The genetic characteristics of indigenous people in the Andes are similar to those of the Japanese, and HTLV-I is generally detected in both groups. To clarify the common origin of HTLV-I in Asia and the Andes, we analyzed HTLV-I provirus DNA from Andean mummies about 1,500 years old. Two of 104 mummy bone marrow specimens yielded a band of human beta-globin gene DNA 110 base pairs in length, and one of these two produced bands of HTLV-I-pX (open reading frame encoding p40x, p27x) and HTLV-I-LTR (long terminal repeat) gene DNA 159 base pairs and 157 base pairs in length, respectively. The nucleotide sequences of ancient HTLV-I-pX and HTLV-I-LTR clones isolated from mummy bone marrow were similar to those in contemporary Andeans and Japanese, although there was microheterogeneity in the sequences of some mummy DNA clones. This result provides evidence that HTLV-I was carried with ancient Mongoloids to the Andes before the Colonial era. Analysis of ancient HTLV-I sequences could be a useful tool for studying the history of human retroviral infection as well as human prehistoric migration.  相似文献   
109.
The purpose ofthis study was to test the hypothesis that regulated body temperatureis decreased in the preovulatory phase in eumenorrheic women. Six womenwere studied in both the preovulatory phase (Preov-2;days 9-12), which was 1-2days before predicted ovulation when 17-estradiol(E2) was estimated to peak, andin the follicular phase (F; days2-6). The subjects walked on a treadmill (~225W · m2)in a warm chamber (ambient temperature = 30°C; dew-pointtemperature = 11.5°C) while heavily clothed.E2, esophageal temperature(Tes), local skin temperatures,and local sweating rate were measured. The estimate of when theE2 surge would occur was correctfor four of six subjects. In these four subjects,E2 increased(P  0.05) from 42.0 ± 24.5 pg/mlduring F to 123.2 ± 31.3 pg/ml during Preov-2. RestingTes was 37.02 ± 0.20°Cduring F and 36.76 ± 0.28°C during Preov-2(P  0.05). TheTes threshold for sweating wasdecreased (P  0.05) from 36.88 ± 0.27°C during F to 36.64 ± 0.35°C during Preov-2. Both meanskin and mean body temperatures were decreased during rest in Preov-2group. The hypothesis that regulated body temperature is decreasedduring the preovulatory phase is supported.

  相似文献   
110.
The molecular basis for the transport of manganese across membranes in plant cells is poorly understood. We have found that IRT1, an Arabidopsis thaliana metal ion transporter, can complement a mutant Saccharomyces cerevisiae strain defective in high-affinity manganese uptake (smf1). The IRT1 protein has previously been identified as an iron transporter. The current studies demonstrated that IRT1, when expressed in yeast, can transport manganese as well. This manganese uptake activity was inhibited by cadmium, iron(II) and zinc, suggesting that IRT1 can transport these metals. The IRT1 cDNA also complements a zinc uptake-deficient yeast mutant strain (zrt1zrt2), and IRT1-dependent zinc transport in yeast cells is inhibited by cadmium, copper, cobalt and iron(III). However, IRT1 did not complement a copper uptake-deficient yeast mutant (ctr1), implying that this transporter is not involved in the uptake of copper in plant cells. The expression of IRT1 is enhanced in A. thaliana plants grown under iron deficiency. Under these conditions, there were increased levels of root-associated manganese, zinc and cobalt, suggesting that, in addition to iron, IRT1 mediates uptake of these metals into plant cells. Taken together, these data indicate that the IRT1 protein is a broad-range metal ion transporter in plants.  相似文献   
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