Objective:Small cell lung carcinoma(SCLC)is considered one of the most aggressive types of lung cancer due to its rapid growth and early metastasis.No tumor markers or therapeutic targets have been demonstrated to be ...Objective:Small cell lung carcinoma(SCLC)is considered one of the most aggressive types of lung cancer due to its rapid growth and early metastasis.No tumor markers or therapeutic targets have been demonstrated to be specific or effective in SCLC to date.This study aims to evaluate the potential of Flotillin1(Flot1)as a target of SCLC treatment.Methods:Flot1 expression level in the tissue of SCLC and other tissue of lung disease was detected using immunohistochemical staining.Transwell and Matrigel assays were employed to examine migration and invasion of cancer cells.Flow cytometry and xCELLigence system were used to evaluate cell apoptosis and cell viability,respectively.Expression levels of Flot1,epithelialmesenchymal transition(EMT)marker E-cadherin,vimentin,cyclinD1,TGF-β-Smad2/3,and p-AKT were examined using Western blot.Furthermore,xenograft tumor in nude mice was used to evaluate the growth and metastasis of NCI-H446 cells in vivo.Results:Our results demonstrated that Flot1 is highly expressed in SCLC samples and that its expression correlates strongly with clinical stage,distant metastasis,and poor survival.The knockdown of Flot1 decreased the growth,migration,and invasiveness of SCLC cells and reversed EMT phenotype in vitro and in vivo,while enhanced Flot1 expression exhibited the opposite behavior.Gene expression profile analysis demonstrated that Flot1-regulated genes frequently mapped to the AKT and TGF-β-Smad2/3pathways.Our results further revealed that Flot1 affected the progression of SCLC via regulation of EMT progression.Conclusions:These findings indicated an oncogenic role of Flot1 via promoting EMT in SCLC and suggested its potential as a tumor marker and prognostic indicator.展开更多
文摘TGF-β/Nodal信号通路在斑马鱼胚胎背腹分化过程中发挥重要作用。为了进一步探究该信号通路的功能及作用机制,文章采用酵母双杂交的方法,以斑马鱼Smad2/3a为诱饵蛋白筛选得到一系列Smad2/3a的互作蛋白,其中之一为Rbb4l(Retinoblastoma binding protein 4,like)。已有的报道表明,Rbb4l的人类同源蛋白RBBP4(Retino blastoma binding protein 4)是染色质修饰相关的复合体的组成成分,但它在脊椎动物胚胎发育过程中的作用还知之甚少。文章通过体外及体内的一系列实验表明,Rbb4l能直接与Smad3a互作,增强TGF-β/Nodal信号。在斑马鱼胚胎中过表达rbb4l导致胚胎的背部化,伴随着背部标记基因表达区域的扩大和腹部标记基因表达区域的缩小。相反,在胚胎中下调rbb4l的表达,可以导致胚胎在24 hpf(hours post-fertilization)左右出现腹部化的表型。文章进一步通过一系列的挽救实验,证明在缺少Nodal信号的情况下,rbb4l的过表达不能引起胚胎的背部化。综上所述,Rbb4l可以增强Nodal/Smad2/3信号,并且这种正向调节的功能依赖于Nodal信号本身。
基金the National Natural Science Foundation of China (Grant No. 81472661, 81490753, 81230047, 81672743, 81772550) Postdoctoral Science Foundation Program of Chinese Academy of Medical Science & Peking Medical College
文摘Objective:Small cell lung carcinoma(SCLC)is considered one of the most aggressive types of lung cancer due to its rapid growth and early metastasis.No tumor markers or therapeutic targets have been demonstrated to be specific or effective in SCLC to date.This study aims to evaluate the potential of Flotillin1(Flot1)as a target of SCLC treatment.Methods:Flot1 expression level in the tissue of SCLC and other tissue of lung disease was detected using immunohistochemical staining.Transwell and Matrigel assays were employed to examine migration and invasion of cancer cells.Flow cytometry and xCELLigence system were used to evaluate cell apoptosis and cell viability,respectively.Expression levels of Flot1,epithelialmesenchymal transition(EMT)marker E-cadherin,vimentin,cyclinD1,TGF-β-Smad2/3,and p-AKT were examined using Western blot.Furthermore,xenograft tumor in nude mice was used to evaluate the growth and metastasis of NCI-H446 cells in vivo.Results:Our results demonstrated that Flot1 is highly expressed in SCLC samples and that its expression correlates strongly with clinical stage,distant metastasis,and poor survival.The knockdown of Flot1 decreased the growth,migration,and invasiveness of SCLC cells and reversed EMT phenotype in vitro and in vivo,while enhanced Flot1 expression exhibited the opposite behavior.Gene expression profile analysis demonstrated that Flot1-regulated genes frequently mapped to the AKT and TGF-β-Smad2/3pathways.Our results further revealed that Flot1 affected the progression of SCLC via regulation of EMT progression.Conclusions:These findings indicated an oncogenic role of Flot1 via promoting EMT in SCLC and suggested its potential as a tumor marker and prognostic indicator.
