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51.
Triple-negative breast cancer (TNBC) is the most malignant and fatal subtype of breast cancer, which has characterized by negativity expression of ER, PR, and HER2. Metastasis is the main factor affecting the prognosis of TNBC, and the process of metastasis is related to abnormal activation of epithelial–mesenchymal transition (EMT). Recent studies have shown that long non-coding RNA (LncRNA) plays an important role in regulating the metastasis and invasion of TNBC. Therefore, based on the metastasis-related EMT signaling pathway, great efforts have confirmed that LncRNA is involved in the molecular mechanism of TNBC metastasis, which will provide new strategies to improve the treatment and prognosis of TNBC. In this review, we summarized many signal pathways related to EMT involved in the transfer process. The advances from the most recent studies of lncRNAs in the EMT-related signal pathways of TNBC metastasis. We also discussed the clinical research, application, and challenges of LncRNA in TNBC.  相似文献   
52.
Wang  Jing  Wen  Xuefa  Lyu  Sidan  Zhang  Xinyu  Li  Shenggong  Guo  Qingjun 《Plant and Soil》2021,460(1-2):609-623
Plant and Soil - Forest recovery from disturbance can alter soil nitrogen (N) status as a result of complex interactions in plant-soil system. The δ15N and δ18O are indicators that...  相似文献   
53.
In response to mitochondrial damage, mitochondria activate mitochondrial dynamics to maintain normal functions, and an imbalance in mitochondrial dynamics triggers multiple programmed cell death processes. Recent studies have shown that phosphoglycerate mutase 5 (PGAM5) is associated with mitochondrial damage. PGAM5 activates mitochondrial biogenesis and mitophagy to promote a cellular compensatory response when mitochondria are mildly damaged, whereas severe damage to mitochondria leads to PGAM5 inducing excessive mitochondria fission, disruption to mitochondrial movement, and amplification of apoptosis, necroptosis and mitophagic death signals, which eventually evoke cell death. PGAM5 functions mainly through protein-protein interactions and specific Ser/Thr/His protein phosphatase activity. PGAM5 is also regulated by mitochondrial proteases. Detection of PGAM5 and its interacting protein partners should enable a more accurate evaluation of mitochondrial damage and a more precise method for the diagnosis and treatment of diseases.  相似文献   
54.
Lin  Xiaohui  Chen  Hongbin  Chen  Manli  Li  Ting  Lai  Yongxing  Lin  Longzai  Lin  Peiqiang  Liu  Ji  Zhang  Yixian  Chen  Ronghua  Du  Houwei  Jiang  Xinhong  Liu  Nan 《Molecular and cellular biochemistry》2021,476(5):2193-2201

Background: Transplantation of bone marrow-derived mesenchymal stem cells (BMSCs) is a potential therapy for cerebral ischemia. However, the underlying protective mechanism remains undetermined. Here, we tested the hypothesis that transplantation of BMSCs via intravenous injection can alleviate neurological functional deficits through activating PI3K/AKT signaling pathway after cerebral ischemia in rats.

Methods: A cerebral ischemic rat model was established by the 2 h middle cerebral artery occlusion (MCAO). Twenty-four hours later, BMSCs (1?×?106 in 1 ml PBS) from SD rats were injected into the tail vein. Neurological function was evaluated by modified neurological severity score (mNSS) and modified adhesive removal test before and on d1, d3, d7, d10 and d14 after MCAO. Protein expressions of AKT, GSK-3β, CRMP-2 and GAP-43 were detected by Western-bolt. NF-200 was detected by immunofluorescence.

Results: BMSCs transplantation did not only significantly improve the mNSS score and the adhesive-removal somatosensory test after MCAO, but also increase the density of NF-200 and the expression of p-AKT, pGSK-3β and GAP-43, while decrease the expression of pCRMP-2. Meanwhile, these effects can be suppressed by LY294002, a specific inhibitor of PI3K/AKT.

Conclusion: These data suggest that transplantation of BMSCs could promote axon growth and neurological deficit recovery after MCAO, which was associated with activation of PI3K/AKT /GSK-3β/CRMP-2 signaling pathway.

  相似文献   
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Zhang  Nan  Zhao  Li  Su  Yan  Liu  Xiaoliang  Zhang  Feilong  Gao  Yiwen 《Neurochemical research》2021,46(3):675-685
Neurochemical Research - Alzheimer’s disease (AD) is a neurodegenerative disorder disease, disturbing people’s normal life. Syringin was mentioned to antagonize Amyloid-β...  相似文献   
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Lipid droplets (LDs) are critical for lipid storage and energy metabolism. LDs form in the endoplasmic reticulum (ER). However, the molecular basis for LD biogenesis remains elusive. Here, we show that fat storage–inducing transmembrane protein 2 (FIT2) interacts with ER tubule-forming proteins Rtn4 and REEP5. The association is mainly transmembrane domain based and stimulated by oleic acid. Depletion of ER tubule-forming proteins decreases the number and size of LDs in cells and Caenorhabditis elegans, mimicking loss of FIT2. Through cytosolic loops, FIT2 binds to cytoskeletal protein septin 7, an interaction that is also required for normal LD biogenesis. Depletion of ER tubule-forming proteins or septins delays nascent LD formation. In addition, FIT2-interacting proteins are up-regulated during adipocyte differentiation, and ER tubule-forming proteins, septin 7, and FIT2 are transiently enriched at LD formation sites. Thus, FIT2-mediated nascent LD biogenesis is facilitated by ER tubule-forming proteins and septins.  相似文献   
59.
Ptk2b has been found playing critical roles in oocyte maturation and subsequent fertilization in vitro. But what is the exact in vivo function in reproduction still elusive. Here, by constructing Ptk2b mutant mice, we found Ptk2b was not essential for mice fertility, unexpectedly, contrary to previously reported in vitro findings, we found Ptk2b ablation significantly improved female fecundity. Follicle counting indicated that the number of primordial follicles and growing follicles in matured mice was significantly increased in the absence of Ptk2b, whereas the primordial follicle formation showed no defects. We also found this regulation was in an autophosphorylation independent pathway, as autophosphorylation site mutant mice (PTK2BY402F) show no phenotype in female fertility. Further biochemistry studies revealed that Ptk2b ablation promotes folliculogenesis via Erk pathway mediate follicle survival. Together, we found a novel biological function of Ptk2b in folliculogenesis, which could be potentially used as a therapeutic target for corresponding infertility.  相似文献   
60.
Nutrient enrichment can reduce ecosystem stability, typically measured as temporal stability of a single function, e.g. plant productivity. Moreover, nutrient enrichment can alter plant–soil interactions (e.g. mycorrhizal symbiosis) that determine plant community composition and productivity. Thus, it is likely that nutrient enrichment and interactions between plants and their soil communities co-determine the stability in plant community composition and productivity. Yet our understanding as to how nutrient enrichment affects multiple facets of ecosystem stability, such as functional and compositional stability, and the role of above–belowground interactions are still lacking. We tested how mycorrhizal suppression and phosphorus (P) addition influenced multiple facets of ecosystem stability in a three-year field study in a temperate steppe. Here we focused on the functional and compositional stability of plant community; functional stability is the temporal community variance in primary productivity; compositional stability is represented by compositional resistance, turnover, species extinction and invasion. Community variance was partitioned into population variance defined as community productivity weighted average of the species temporal variance in performance, and species synchrony defined as the degree of temporal positive covariation among species. Compared to treatments with mycorrhizal suppression, the intact AM fungal communities reduced community variance in primary productivity by reducing species synchrony at high levels of P addition. Species synchrony and population variance were linearly associated with community variance with the intact AM fungal communities, while these relationships were decoupled or weakened by mycorrhizal suppression. The intact AM fungal communities promoted the compositional resistance of plant communities by reducing compositional turnover, but this effect was suppressed by P addition. P addition increased the number of species extinctions and thus promoted compositional turnover. Our study shows P addition and AM fungal communities can jointly and independently modify the various components of ecosystem stability in terms of plant community productivity and composition.  相似文献   
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