Rab11a通过PI3K/AKT和Ras/MEK/ERK信号通路调节胰腺癌细胞凋亡和侵袭

目的:探究Rab11a在胰腺癌中的表达模式及其对肿瘤生长和转移的影响.方法:通过免疫组织化学法、RT-PCR和Western blot检测60例胰腺癌患者的癌组织和癌旁组织中Rab11a的表达.通过对人胰腺癌细胞系PANC1转染靶向Rab11a的小干扰RNA或过表达Rab11a的pcDNA3.1质粒考察Rab11a对细...     

miR-20a靶向CCND1作用PI3K/AKT信号通路抑制皮肤鳞状细胞癌的发展

摘要 目的：探究miR-20a与CCND1蛋白在皮肤鳞状细胞癌（CSCC）中的作用关系,以及其可能涉及的信号通路分子机制。方法：分别收集皮肤鳞状细胞癌患者的皮肤癌组织及其邻近正常皮肤组织,采用qRT-PCR分析组织中miR-20a和CCND1基因表达水平。为探究miR-20a对CSCC细胞的影响,将SCL-1细胞分为对照组（不转染）、miR-NC组（转染miR-NC）和miR-20a mimics组（转染miR-20a mimics）;为探究CCND1与PI3K/AKT信号通路的关系,将SCL-1细胞分为对照组（不转染）、si-NC组（转染si-NC）和si-CCND1组（转染si-CCND1）;为探究miR-20a与CCND1间的作用关系及对CSCC细胞的影响,将SCL-1细胞分为miR-NC组（转染miR-NC）、miR-20a mimics组（转染miR-20a mimics）、mimics+pcDNA组（共转染miR-20a mimics和pcDNA）和mimics+CCND1组（共转染miR-20a mimics和pcDNA-CCND1）。采用Western blot分析p-AKT、AKT、p-PI3K、PI3K和GSK-3β蛋白表达水平;采用MTT检测细胞增殖情况;采用流式细胞术检测细胞凋亡情况;采用Transwell分析细胞迁移和侵袭情况;采用双荧光素酶报告基因检测分析miR-20a与CCND1的靶向关系。结果：CSCC癌组织和SCL-1中miR-20a均低表达,CCND1高表达。与对照组和miR-NC组比较,miR-20a mimics组SCL-1细胞增殖水平以及侵袭和迁移数量均降低（P<0.05）,SCL-1细胞凋亡水平升高（P<0.05）,PI3K和AKT蛋白磷酸化水平降低（P<0.05）。TargetScanHuman数据库分析和双荧光素酶报告基因检测结果显示miR-20a与CCND1存在靶向作用关系。与对照组和si-NC组比较,si-CCND1组SCL-1细胞中CCND1和GSK-3β蛋白表达水平以及PI3K和AKT蛋白磷酸化水平均降低（P<0.01）。与miR-20a mimics组或mimics+pcDNA组比较,mimics+CCND1组SCL-1细胞增殖水平以及侵袭和迁移数量均升高（P<0.05）,SCL-1细胞凋亡水平降低（P<0.05）,PI3K和AKT蛋白磷酸化水平均升高（P<0.05）。结论：过表达miR-20a可能通过靶向抑制CCND1的表达而抑制PI3K/AKT信号通路的激活,从而抑制CSCC细胞的增殖、侵袭和迁移,并促进癌细胞凋亡。     

(E)-3-(3,4,5-Trimethoxyphenyl)-1-(pyridin-4-yl)prop-2-en-1-one,a heterocyclic chalcone is a potent and selective CYP1A1 inhibitor and cancer chemopreventive agent

The overexpression of CYP1 family of enzymes is reported to be associated with development of human carcinomas. It has been well reported that CYP1A1 specific inhibitors prevents carcinogenesis. Herein, thirteen pyridine-4-yl series of chalcones were synthesized and screened for inhibition of CYP1 isoforms 1A1, 1B1 and 1A2 in Sacchrosomes? and live human HEK293 cells. The structure-activity relationship analysis indicated that chalcones bearing tri-alkoxy groups (8a and 8k) on non-heterocyclic ring displayed selective inhibition of CYP1A1 enzyme, with IC₅₀ values of 58 and 65?nM, respectively. The 3,4,5-trimethoxy substituted derivative 8a have shown >10-fold selectivity towards CYP1A1 with respect to other enzymes of the CYP1 sub-family and >100-fold selectivity with respect to CYP2 and CYP3 family of enzymes. The potent and selective CYP1A1 inhibitor 8a displayed antagonism of B[a]P mediated activation of aromatic hydrocarbon receptor (AhR) in yeast cells, and also protected human cells from CYP1A1-mediated B[a]P toxicity in human cells. This potent and selective inhibitor of CYP1A1 enzyme have a potential for development as cancer chemopreventive agent.     

沉默脂肪细胞增强子结合蛋白2通过PI3K/Akt途径抑制肝癌细胞增殖和迁移

脂肪细胞增强子结合蛋白2(AEBP2)作为多梳抑制复合物2(PRC2)的组成蛋白质,参与多种肿瘤细胞的增殖和迁移,然而其在肝癌中的作用尚不清楚。本研究基于UALCAN和Kaplan-Meier Plotter数据库分析发现,AEBP2在肝癌组织中高表达,并且与患者的不良预后呈正相关。实时荧光定量PCR和蛋白质印迹结果证实,AEBP2在肝癌细胞中的表达高于正常肝细胞。在HepG2和Huh-7细胞中转染AEBP2 siRNA,平板克隆、CCK-8、流式细胞术、划痕愈合和Transwell结果显示,沉默AEBP2可以抑制肝癌细胞增殖、迁移和侵袭,并促进细胞凋亡(P＜0.05)。免疫荧光检测和蛋白质印迹结果显示,沉默AEBP2能够抑制肝癌细胞上皮-间质转化(EMT)(P＜0.05)。生物信息学分析结果表明,AEBP2参与调控PI3K/Akt信号通路。蛋白质印迹结果证实,沉默AEBP2能下调PI3K、p-AKT (S473)、mTOR、MMP-2和MMP-9的蛋白质表达水平(P＜0.05)。此外,沉默AEBP2对HepG2细胞迁移和侵袭的影响可被PI3K/Akt通路激动剂胰岛素样生长因子1(IGF-1)部分逆转(P＜0.01)。综上所述,AEBP2可能通过调节PI3K/Akt途径促进肝癌细胞增殖和迁移。本研究为AEBP2在肝癌中的作用提供理论依据。     

Retracted: Downregulated microRNA-135a ameliorates rheumatoid arthritis by inactivation of the phosphatidylinositol 3-kinase/AKT signaling pathway via phosphatidylinositol 3-kinase regulatory subunit 2

Synovial fibroblasts (SFs) of rheumatoid arthritis (RA) are phenotypically aggressive, typically progressing into arthritic cartilage degradation. Throughout our study, we made explorations into the effects of microRNA-135a (miR-135a) on the SFs involved in RA by mediating the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway via regulation of phosphatidylinositol 3-kinase regulatory subunit 2 (PIK3R2). The expression of PI3K was higher, the expression of PIK3R2 was lower, and AKT was phosphorylated in the RA synovial tissues, relative to the levels found in the normal synovial tissues. We predicted miR-135a to be a candidate miR targeting PIK3R2 using an online website, microRNA.org, which was verified with a dual-luciferase reporter gene assay. Subsequently, high miR-135a expression was observed in RA synovial tissues. To study the effect of the interaction between miR-135a and PIK3R2 in RA, the SFs isolated from RA samples were cultured and transfected with mimic, inhibitor, and small interfering RNA. The proliferation, invasion, and apoptosis of the SFs were detected after the transfection. The cells transfected with miR-135a inhibitor showed inhibited cell proliferation, migration, and invasion, while also displaying promoted cell apoptosis, G0/G1 cell ratio, and decreased S cell ratio, through upregulation of PIK3R2 and inactivation of the PI3K/AKT signaling pathway. These findings provided evidence that downregulation of miR-135a inhibits proliferation, migration, and invasion and promotes apoptosis of SFs in RA by upregulating the PIK3R2 coupled with inactivating the PI3K/AKT signaling pathway. The downregulation of miR-135a might be a potential target in the treatment of RA.     

1,7-Bis(4-hydroxyphenyl)-1,4-heptadien-3-one induces lung cancer cell apoptosis via the PI3K/Akt and ERK1/2 pathways

1,7-Bis(4-hydroxyphenyl)-1,4-heptadien-3-one (EB30) is a diarylheptanoid-like compound isolated from Viscum coloratum. This curcumin analog exhibits significant cytotoxic activity against HeLa, SGC-7901, and MCF-7 cells. However, little is known about the anticancer effects and mechanisms of EB30 in human lung cancer. The current study reports that EB30 significantly reduced the cell viability of A549 and NCI-H292 human lung cancer cells. Further examination revealed that EB30 not only induced cell cycle arrest and promoted the generation of reactive oxygen species (ROS) but also induced cell apoptosis through the intrinsic and extrinsic signaling pathways. Furthermore, EB30 upregulated the expression levels of p-ERK1/2 and p-P90RSK, whereas downregulating the phosphorylation of Akt and P70RSK. Cell viability was further inhibited by the combination of EB30 with LY294002 (a specific PI3K inhibitor) or U0126 (a MEK inhibitor). The current study indicates that EB30 is a potential anticancer agent that induces cell apoptosis via suppression of the PI3K/Akt pathway and activation of the ERK1/2 pathway.     

ASIC1a stimulates the resistance of human hepatocellular carcinoma by promoting EMT via the AKT/GSK3β/Snail pathway driven by TGFβ/Smad signals

Multidrug resistance is the main obstacle to curing hepatocellular carcinoma (HCC). Acid‐sensing ion channel 1a (ASIC1a) has critical roles in all stages of cancer progression, especially invasion and metastasis, and in resistance to therapy. Epithelial to mesenchymal transition (EMT) transforms epithelial cells into mesenchymal cells after being stimulated by extracellular factors and is closely related to tumour infiltration and resistance. We used Western blotting, immunofluorescence, qRT‐PCR, immunohistochemical staining, MTT, colony formation and scratch healing assay to determine ASIC1a levels and its relationship to cell proliferation, migration and invasion. ASIC1a is overexpressed in HCC tissues, and the amount increased in resistant HCC cells. EMT occurred more frequently in drug‐resistant cells than in parental cells. Inactivation of ASIC1a inhibited cell migration and invasion and increased the chemosensitivity of cells through EMT. Overexpression of ASIC1a upregulated EMT and increased the cells’ proliferation, migration and invasion and induced drug resistance; knocking down ASIC1a with shRNA had the opposite effects. ASIC1a increased cell migration and invasion through EMT by regulating α and β‐catenin, vimentin and fibronectin expression via the AKT/GSK‐3β/Snail pathway driven by TGFβ/Smad signals. ASIC1a mediates drug resistance of HCC through EMT via the AKT/GSK‐3β/Snail pathway.     

Discovery of (1R,6S)-5-[4-(1-cyclobutyl-piperidin-4-yloxy)-phenyl]-3,4-diaza-bicyclo[4.1.0]hept-4-en-2-one (R,S-4a): Histamine H3 receptor inverse agonist demonstrating potent cognitive enhancing and wake promoting activity

A series of fused cyclopropyl-4,5-dihydropyridazin-3-one (3,4-diaza-bicyclo[4.1.0]hept-4-en-2-one) phenoxypiperidine analogs was designed and synthesized, leading to the identification of (1R,6S)-5-[4-(1-cyclobutyl-piperidin-4-yloxy)-phenyl]-3,4-diaza-bicyclo[4.1.0]hept-4-en-2-one (R,S-4a) as a second-generation pyridazin-3-one H₃R antagonist. Compound R,S-4a was a potent H₃R functional antagonist in vivo in the rat dipsogenia model, demonstrated potent wake activity in the rat EEG/EMG model, and enhanced short-term memory in the rat social recognition memory model at doses as low as 0.03–0.3 mg/kg po.