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991.
Rui-Zan Shi Yi-Fan He Jie Wen Ya-Nan Niu Yu Gao Lin-Hong Liu Xuan-Ping Zhang Yan Wang Xiu-Li Zhang Hui-Feng Zhang Min Chen Xiao-ling Hu 《Cell biology international》2021,45(8):1644-1653
Overexpression of breast cancer resistance protein (BCRP) plays a crucial role in the acquired multidrug resistance (MDR) in breast cancer. The elucidation of molecular events that confer BCRP-mediated MDR is of major therapeutic importance in breast cancer. Epithelial cell adhesion molecule (EpCAM) has been implicated in tumor progression and drug resistance in various types of cancers, including breast cancer. However, the role of EpCAM in BCRP-mediated MDR in breast cancer remains unknown. In the present study, we revealed that EpCAM expression was upregulated in BCRP-overexpressing breast cancer MCF-7/MX cells, and EpCAM knockdown using siRNA reduced BCRP expression and increased the sensitivity of MCF-7/MX cells to mitoxantrone (MX). The epithelial–mesenchymal transition (EMT) promoted BCRP-mediated MDR in breast cancer cells, and EpCAM knockdown partially suppressed EMT progression in MCF-7/MX cells. In addition, Wnt/β-catenin signaling was activated in MCF-7/MX cells, and the inhibition of this signaling attenuated EpCAM and BCRP expression and partially reversed EMT. Together, this study illustrates that EpCAM upregulation by Wnt/β-catenin signaling induces partial EMT to promote BCRP-mediated MDR resistance in breast cancer cells. EpCAM may be a potential therapeutic target for overcoming BCRP-mediated resistance in human breast cancer. 相似文献
992.
993.
Yin‐Hui Zhao Cai‐Fu Shen Guang‐Jun Wang Yan Kang Yun‐Hong Song Jiang‐Wei Liu 《Journal of biochemical and molecular toxicology》2021,35(1)
Curcumin exhibits anti‐inflammatory and antioxidant activities. We investigated the protective effects of curcumin in a renal injury rat model under dry‐heat conditions. We divided Sprague‐Dawley rats into four groups: dry‐heat 0‐ (normal temperature control group), 50‐, 100‐, and 150‐minute groups. Each group was divided into five subgroups (n = 10): normal saline (NS), sodium carboxymethylcellulose (CMCNa), and curcumin pretreated low, medium, and high‐dose (50, 100, and 200 mg/kg, respectively) groups. Compared to the normal temperature group, serum creatinine, blood urea nitrogen, urinary kidney injury molecule‐1, and neutrophil gelatinase‐associated load changes in lipoprotein (NGAL) levels were significantly increased in the dry‐heat environment group (P < .05); inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) expression and malondialdehyde (MDA) and related inflammatory factor levels were increased in the kidney tissue. Superoxide dismutase (SOD) and catalase (CAT) levels were decreased. However, following all curcumin pretreatment, the serum levels of kidney injury indicators and NGAL were decreased in the urine compared to those in the NS and CMCNa groups (P < .05), whereas renal SOD and CAT activities were increased and MDA was decreased (P < .05). Renal tissues of the 150‐minute group showed obvious pathological changes. Compared to the NS group, pathological changes in the renal tissues of the 100‐ and 200‐mg/kg curcumin groups were significantly reduced. Furthermore, iNOS and COX‐2 expression and inflammatory factor levels were decreased after curcumin treatment. Curcumin exerted renoprotective effects that were likely mediated by its antioxidant and anti‐inflammatory effects in a dry‐heat environment rat model. 相似文献
994.
995.
Peng Xue Tao Jiang Juan Zhu Meixian Wang Qiaoling Zhao Jinshan Huang Shunming Tang Xingjia Shen 《Journal of Asia》2021,24(1):42-49
N6-methyladeosine (m6A) plays an important role in virus infection and replication. Bombyx mori nuclear polyhedrosis is caused by Bombyx mori nucleopolyhedrovirus (BmNPV) infection. Expression levels of m6A-modification-related genes after the infection of BmNPV were detected at first. Then, expression levels of BmNPV nucleocapsid protein gene VP39 and envelope fusion protein gene GP64 after knockdown of METTL3in vitro were quantified to identify the effect of m6A modification on BmNPV. BmNPV firstly infects the larval midgut in case of oral infection. Subsequently, to clarify the relationship between m6A modification and resistance of the silkworm to BmNPV, we detected the expression levels of m6A-modification-related genes invivo before and after infection of BmNPV. The results indicated that low METTL3 level hindered the proliferation of BmNPV to some extent, and silkworm strain with low METTL3 level showed stronger resistance against BmNPV. This study will accumulate new experimental data for elucidating the resistance mechanism of silkworm against BmNPV. 相似文献
996.
Muhammad Nasir Chen-chen Zhao Jun-yu Luo Xiang-zhen Zhu Xue-ke Gao Mazher F. Iqbal Ji-chao Ji Shuai Zhang Jin-jie Cui 《Journal of Asia》2021,24(1):297-307
The genetically modified cotton holding Bt proteins, is noxious to bollworms larvae but very little is known about its impact on population of non-target spiders within the field. Studies conducted with the aim to identify spiders along with their abundance, prevalence pattern, preying habit on insect pests in Bt cotton (L280, Cry2Ab4) and commonness of symbiotic bacteria in these spiders. Spiders collections were made via vial tapping/jarring, from May to end of October (2018). In total, 13,342 spiders were recorded during the entire cropping season. Least relative abundance was in May (0.28%), highest in August (30.39%) while ahead decline was observed, reached to 12% in October. The 27 species were verified, least richness was in May (3 species), high in August (19 species), later in the end, reduced to 7 species. High abundance was of Hylyphantes graminicola (68.56%) and Neoscona theisi (19.98%). Existence of H. graminicola and Pardosa astrigera observed during the whole cropping season. Presence of seven guilds among spiders had a diverse nature of hunting insect pests and on number of species existed in the crop, maximum was from direct hunting habit. Composition and community structure of microbiota varied as of spider species. Proteobacteria was the most abundant bacterial phylum and topmost genus was Wolbachia in observed spiders. Five groups of bacteria distinguished across 4 clusters of spiders depending on core community of symbiotic bacterial genera. This effort is an initial step to get knowhow about spiders in Bt cotton, which will facilitate future research studies concerning spiders. 相似文献
997.
Gou Xue Xu Dan Li Fengyang Hou Kai Fang Weirong Li Yunman 《Journal of physiology and biochemistry》2021,77(4):511-529
Journal of Physiology and Biochemistry - Stroke is a common disease with high mortality and disability worldwide. Different forms of cell deaths, including apoptosis and necrosis, occur in ischemic... 相似文献
998.
Jiao Yan Zhao Dandan Gao Fuhua Hu Xiaoyan Hu Xinxin Li Mei Cui Ying Wei Xiaoqing Xie Ce Zhao Ying Gao Ying 《Journal of physiology and biochemistry》2021,77(1):47-61
Journal of Physiology and Biochemistry - Endothelial injury, which can cause endothelial inflammation and dysfunction, is an important mechanism for the development of atherosclerotic plaque. This... 相似文献
999.
Jibing Li Chunling Luo Dayi Zhang Xuan Zhao Yeliang Dai Xixi Cai Gan Zhang 《Environmental microbiology》2021,23(11):7042-7055
Rhizoremediation is a potential technique for polycyclic aromatic hydrocarbon (PAH) remediation; however, the catabolic pathways of in situ rhizosphere PAH degraders and the main factors driving PAH rhizoremediation remain unclear. To address these issues, stable-isotope-probing coupled with metagenomics and molecular ecological network analyses were first used to investigate the phenanthrene rhizoremediation by three different prairie grasses in this study. All rhizospheres exhibited a significant increase in phenanthrene removal and markedly modified the diversity of phenanthrene degraders by increasing their populations and interactions with other microbes. Of all the active phenanthrene degraders, Marinobacter and Enterobacteriaceae dominated in the bare and switchgrass rhizosphere respectively; Achromobacter was markedly enriched in ryegrass and tall fescue rhizospheres. Metagenomes of 13C-DNA illustrated several complete pathways of phenanthrene degradation for each rhizosphere, which clearly explained their unique rhizoremediation mechanisms. Additionally, propanoate and inositol phosphate of carbohydrates were identified as the dominant factors that drove PAH rhizoremediation by strengthening the ecological networks of soil microbial communities. This was verified by the results of rhizospheric and non-rhizospheric treatments supplemented with these two substances, further confirming their key roles in PAH removal and in situ PAH rhizoremediation. Our study offers novel insights into the mechanisms of in situ rhizoremediation at PAH-contaminated sites. 相似文献