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981.
Qinglian Wu Xian Bao Wanqian Guo Bing Wang Yunxi Li Haichao Luo Huazhe Wang Nanqi Ren 《Biotechnology advances》2019,37(5):599-615
Alternative chemicals to diverse fossil-fuel-based products is urgently needed to mitigate the adverse impacts of fossil fuel depletion on human development. To this end, researchers have focused on the production of biochemical from readily available and affordable waste biomass. This is consistent with current guidelines for sustainable development and provides great advantages related to economy and environment. The search for suitable biochemical products is in progress worldwide. Therefore, this review recommends a biochemical (i.e., medium chain carboxylic acids (MCCAs)) utilizing an emerging biotechnological production platform called the chain elongation (CE) process. This work covers comprehensive introduction of the CE mechanism, functional microbes, available feedstock types and corresponding utilization strategies, major methods to enhance the performance of MCCAs production, and the challenges that need to be addressed for practical application. This work is expected to provide a thorough understanding of the CE technology, to guide and inspire researchers to solve existing problems in depth, and motivate large-scale MCCAs production. 相似文献
982.
Zhuang Luo Wei Chen Wenjuan Wu Wei Luo Tingting Zhu Gang Guo Liyan Zhang Chu Wang Min Li Shaoqing Shi 《Journal of cellular biochemistry》2019,120(7):11890-11899
Metformin, a first-line antidiabetic drug, has been reported with anticancer activities in many types of cancer. However, its molecular mechanisms remain largely unknown. As a member of inhibitor of apoptosis proteins, survivin plays an important role in the regulation of cell death. In the present study, we investigated the role of survivin in metformin-induced anticancer activity in non–small cell lung cancer in vitro. Metformin mainly induced apoptotic cell death in A549 and H460 cell lines. It remarkably suppressed the expression of survivin, decreased the stability of this protein, then promoted its proteasomal degradation. Moreover, metformin greatly suppressed protein kinase A (PKA) activity and induced its downstream glycogen synthase kinase 3β (GSK-3β) activation. PKA activators, both 8-Br-cAMP and forskolin, significantly increased the expression of survivin. Consistently both GSK-3β inhibitor LiCl and siRNA restored the expression of survivin in lung cancer cells. Furthermore, metformin induced adenosine 5′-monophosphate-activated protein kinase (AMPK) activation. Suppression of the activity of AMPK with Compound C reversed the degradation of survivin induced by metformin, and meanwhile, restored the activity of PKA and GSK-3β. These results suggest that metformin kills lung cancer cells through AMPK/PKA/GSK-3β-axis–mediated survivin degradation, providing novel insights into the anticancer effects of metformin. 相似文献
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Kunlin Yu Jishi Wang Tingting Lu Dan Ma Danna Wei Yongling Guo Bingqin Cheng Weili Wang Qin Fang 《Journal of cellular biochemistry》2019,120(10):17791-17810
Chemoresistance often causes treatment failure of B-cell acute lymphoblastic leukemia (B-ALL). However, the mechanism remains unclear at present. Herein, overexpression of heme oxygenase-1 (HO-1) was found in the bone marrow stromal cells (BMSCs) from B-ALL patients developing resistance to vincristine (VCR), a chemotherapeutic agent. Two B-ALL cell lines Super B15 and CCRF-SB were cocultured with BMSCs transfected with lentivirus to regulate the expression of HO-1. Silencing HO-1 expression in BMSCs increased the apoptotic rates of B-ALL cell lines induced by VCR, whereas upregulating HO-1 expression reduced the rate. Cell cycle can be arrested in the G2/M phase by VCR. In contrast, B-ALL cells were arrested in the G0/G1 phase due to HO-1 overexpression in BMSCs, which avoided damage from the G2/M phase. Vascular endothelial growth factor (VEGF) in BMSCs, as a key factor in the microenvironment-associated chemoresistance, was also positively coexpressed with HO-1. VEGF secretion was markedly increased in BMSCs with HO-1 upregulation but decreased in BMSCs with HO-1 silencing. B-ALL cell lines became resistant to VCR when cultured with VEGF recombinant protein, so VEGF secretion induced by HO-1 expression may promote the VCR resistance of B-ALL cells. As to the molecular mechanism, the PI3K/AKT pathway mediated regulation of VEGF by HO-1. In conclusion, this study clarifies a mechanism by which B-ALL is induced to resist VCR through HO-1 overexpression in BMSCs, and provides a novel strategy for overcoming VCR resistance in clinical practice. 相似文献
985.
Haifeng Liu Xiuying Shi Xiaoxi Fan Di Zhang Biying Jiang Yang Zhao Chuifeng Fan 《Journal of cellular biochemistry》2019,120(8):12340-12347
Zbed3, a BED finger domain-containing protein was found to promote cancer proliferation by regulating β-catenin expression through interacting with Axin. But whether and how BED finger domain function in regulating cancer proliferation is unknown. We constructed five mutants of Zbed3, which lacks the Axin-Zbed3 binding site, and the 43 to 52, 69 to 77, 87 to 92, and 97 to 104 sequences in BED finger domain, respectively and named them as Z-A, Z1, Z2, Z3, and Z4. Transfection of both wild-type of Zbed3 and the mutants Z1, Z3, and Z4 (P < 0.05), but not Z2 (P > 0.05) significantly upregulated β-catenin expression in NCI-H1299 cells. Overexpression of both wild-type of Zbed3 and the mutants Z1, Z3, and Z4 (P < 0.05) but not Z2 (P > 0.05) significantly promoted cancer cell proliferation and invasion. The ability of proliferation (P < 0.05) but not invasion (P < 0.05) of cancer cells transfected with Z1 and Z4 was significantly lower than that with wild-type Zbed3 and Z3. Overexpression of wild-type Zbed3 (P < 0.05) but not the mutant Z-A, which lacks the binding site with Axin and Z2 (P > 0.05) significantly upregulated the interaction of Axin and Zbed3, β-catenin expression and the activity of Wnt signaling. Both overexpression of wild-type Zbed3 and the mutant Z1 and Z4 significantly upregulated the activity of Wnt signaling and promoted cancer cell proliferation (P < 0.05) but only overexpression of wild-type Zbed3 (P < 0.05), but not the mutant Z1, and Z4 (P > 0.05), significantly upregulated the expression of proliferating cell nuclear antigen (PCNA) in NCI-H1299 cells. These results indicate that Zbed3 may promote lung cancer cell proliferation through regulating PCNA expression besides regulating β-catenin expression and BED finger domain can impact on this function. 相似文献
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