微小RNA-30e调控EMT对胃癌侵袭和迁移影响的研究

目的:探讨微小RNA-30e(miR-30e)对胃癌细胞迁移和侵袭能力的影响及可能的作用机制。方法:利用Transwell实验和细胞划痕实验检测胃癌细胞系BGC823侵袭和迁移的能力;以脂质体包裹合成miR-30e转染至BGC823细胞,并设空白载体作为对照组;Real-time PCR分别检测实验组和对照组细胞中miR-30e的表达。RT-PCR检测过表达miR-30e后对上皮细胞间充质转化(EMT)相关标记分子Snail、Vimentin、N-cadherin和E-cadherin表达的影响。结果:miR-30e转染至胃癌细胞后,抑制EMT通路主要因子Snail,Vimentin和N-cadherin m RNA和蛋白质表达,而增加E-cadherin的mRNA和蛋白质表达;miR-30e通过TGF-β对BGC823细胞的侵袭和迁移能力有明显的抑制作用。结论:miR-30e可能是肿瘤细胞EMT过程的关键靶标靶点,阻断EMT过程,可以抑制胃癌细胞的侵袭和迁移能力。     

FOXG1在结直肠癌侵袭及转移中的作用及机制

构建叉头框G1(Forkhead box G1,FOXG1)的慢病毒干扰(shRNA)质粒及表达质粒,通过敲低和过表达FOXG1探讨其对结直肠癌细胞上皮-间质转化EMT的作用及其机制。应用Western blotting检测FOXG1在RKO、SW480、SW620、LOVO、DLD-1五种结直肠癌细胞中蛋白的表达水平,设计并合成FOXG1的shRNA片段(shFOXG1),运用DNA重组技术获得重组质粒,经双酶切技术及测序方法鉴定后进行慢病毒的包装、纯化及稳定转染,经筛选后获得稳定的结直肠癌细胞株,通过Western blotting和qRT-PCR技术检测FOXG1敲低和过表达效率及EMT关键因子E-cadherin、Vimentin、Fibronectin、Snail、Twist mRNA和蛋白的变化,光学显微镜观察敲低后细胞形态学变化,通过划痕实验检测迁移能力变化,Transwell检测侵袭迁移能力的变化。5种结直肠癌细胞中,FOXG1在RKO细胞中蛋白表达量最高,而在DLD-1细胞中表达量最低,与对照组相比较,在RKO细胞中敲低FOXG1,细胞形态由长梭型变成了类圆形或者多边形,细胞极性和紧密连接增加,细胞迁移距离明显降低,侵袭转移穿过小室的细胞数也明显减少,EMT关键因子E-cadherin表达增高,Vimentin、Fibronectin、Snail、Twist表达降低,过表达FOXG1组则相反。FOXG1在结直肠癌中高表达,这种基因的高表达能够促进结直肠癌细胞的侵袭和转移,对结直肠癌细胞的EMT起着重要的调控作用。     

GRP78在食管癌细胞ECA-109增殖过程中的功能研究

食管癌在中国是高发性肿瘤,并具有较高的致死率。肿瘤细胞的持续增殖与细胞增殖失调密切相关。肿瘤细胞在增殖过程中需要合成大量蛋白质,葡萄糖调节蛋白78(glucose regulatedprotein,GRP78)作为分子伴侣,在蛋白质的折叠、组装、修饰和错误折叠蛋白的降解过程中发挥着重要作用。该研究通过构建pGRP78-EGFP-N1重组质粒,瞬时转染ECA-109细胞,研究GRP78过表达对细胞增殖能力的影响;采用RNA干扰技术,瞬时转染靶向GRP78的siRNA,研究敲低GRP78对细胞增殖能力的影响。该研究发现GRP78过表达后,更多的细胞从G1期进入S期和G2/M期,细胞增殖速率加快,细胞克隆形成率亦明显提高;敲低GRP78后,细胞更多地被阻滞在G1期而无法进入S期和G2/M期,细胞增殖速率减慢,细胞克隆形成率降低。GRP78可能通过调节细胞周期而促进ECA-109细胞的增殖。     

TGF-β1对乳腺癌细胞系Snail表达的影响

目的通过TGF-β1诱导乳腺癌MCF-7发生上皮-间质转化(epithelial-mesenchymal transition,EMT)后检测锌指转录因子Snail表达的改变,探讨Snail在EMT及乳腺癌发生发展中的作用。方法常规培养乳腺癌细胞株MCF-7后,用TGF-β1诱导其发生EMT,用Transwell侵袭小室法进行细胞体外侵袭能力检测;用免疫组织化学方法及免疫荧光检测E-cadherin、Vi mentin、Snail的表达;用real ti me PCR检测E-cadherin、Vi mentin、Snail mRNA的表达。结果TGF-β1处理72h后的MCF-7细胞穿透能力明显增强。E-cadherin蛋白及mRNA表达减少,Vi mentin、Snail蛋白及mRNA表达增加。结论E-cadherin、Vi mentin是细胞发生EMT的重要生物学标志,Snail可能在转录水平上调控E-cadherin、Vi mentin蛋白的表达,Snail在EMT和乳腺癌的发生发展中起着重要的作用。     

GJA1在结直肠癌组织中表达及促进侵袭转移的研究

摘要 目的：间隙连接Alpha-1蛋白（Gap Junction Alpha-1,GJA1）是间隙连接中分布最广泛的蛋白,并在多种肿瘤中起促癌作用,但其在结直肠癌发生、发展的作用研究甚少。本实验旨在探究GJA1在结直肠癌组织中的表达情况及其对结直肠癌细胞系侵袭、转移能力的影响,以期为结直肠癌的诊断和预后寻找新的生物标志物。方法：收集92对结直肠癌及其癌旁组织样本,提取组织RNA,利用qRT-PCR检测GJA1相对表达量,并分析GJA1表达与临床病理特征及预后的相关性。在HCT116和HCT8两种结直肠癌细胞系中分别构建GJA1过表达载体和敲减载体,利用qRT-PCR和、Western Blot检测上皮间充质转化（epithelial-mesenchymal transition, EMT）相关蛋白E-Cadherin、N-Cadherin、Vimentin和Snail的表达变化,利用Wound healing和Transwell实验观察其迁移、侵袭能力的变化。结果：相对于癌旁组织,GJA1在结直肠癌组织中显著低表达。并且结直肠癌中低表达的GJA1与肿瘤分化程度、浸润深度、淋巴血管转移相关,低表达GJA1结直肠癌患者显示更差的总体生存率和更低的无病生存率。此外,过表达GJA1后,结直肠癌细胞E-cadherin的表达升高,N-cadherin、Vimentin和Snail的表达降低,划痕愈合减慢,Transwell转移细胞减少;而敲减GJA1后,结直肠癌细胞E-Cadherin的表达降低,N-Cadherin、Vimentin和Snail的表达升高,划痕愈合加快,Transwell转移细胞增多。结论：GJA1在结直肠癌中低表达,其表达降低可通过EMT促进结直肠癌的侵袭、转移并影响病人预后。     

幽门螺杆菌致炎症微环境促进结肠癌SW620细胞发生EMT

该文探讨了幽门螺杆菌(Helicobacter pylori, HP)炎症微环境对结肠癌SW620细胞发生上皮-间质转化(epithelial mesenchymal transformation, EMT)的影响。使用ELISA方法检测HP干预U937细胞后上清中炎症因子MIF、IL-1β等的变化;采用RT-PCR方法检测MIF、IL-1β、NF-κB基因水平的变化;细胞划痕实验检测炎症上清处理SW620细胞后SW620细胞的侵袭迁移能力; CCK-8方法检测HP处理U937细胞后炎症上清对SW620细胞增殖活性的影响;免疫荧光实验检测炎症上清处理SW620细胞后SW620细胞EMT相关蛋白Vimentin的荧光变化; Western blot实验检测脂多糖(LPS)上清干预SW620细胞后EMT相关蛋白Vimentin、E-cadherin和N-cadherin的变化; Western blot实验检测HP干预U937细胞后NF-κB蛋白,炎症上清处理SW620细胞后EMT相关蛋白Vimentin、E-cadherin和N-cadherin的变化。结果显示, HP干预U937细胞后引起巨噬细胞移动抑制因子(MIF)、白细胞介素-1β(IL-1β)和NF-κB等相关炎症因子及基因表达升高; CCK-8结果表明HP干预U937细胞后, U937细胞毒性增强;划痕实验结果表明在12 h、24 h、36 h时,随着时间点的推移, SW620细胞的侵袭迁移能力有所增强;免疫荧光实验结果显示SW620细胞Vimentin绿色点状聚集显著增加; Western blot结果显示在16 h、24 h时间点U937细胞NF-κB蛋白表达明显升高; LPS上清干预SW620细胞后Vimentin蛋白表达无明显变化,N-cadherin蛋白24 h组表达减少, E-cadherin蛋白增多, HP炎症微环境上清干预SW620细胞后12 h、24 h、36 h时,随着时间点推移SW620细胞Vimentin蛋白表达显著增加, E-cadherin和N-cadherin蛋白表达显著减少。该实验研究结果表明,幽门螺杆菌致炎症微环境可以促进SW620细胞发生EMT。     

水苏碱调节CXCL12/CXCR4轴对子宫内膜癌细胞增殖、迁移和侵袭的影响

该研究主要探讨水苏碱(STA)对子宫内膜癌(EC)细胞增殖、侵袭和迁移的影响以及对CXCL12/CXCR4轴的调节机制。将EC细胞分为对照组(Control组)、CXCL12/CXCR4抑制剂组(AMD 3100组)、STA-L组(STA-L)、STA-H组(STA-H)、STA-H+CXCL12组。采用CCK-8检测细胞增殖情况;克隆形成实验检测细胞克隆能力;流式细胞术检测细胞凋亡情况; Transwell实验检测细胞的迁移和侵袭能力; Western blot检测细胞中上皮钙黏蛋白(E-cadherin)、波形蛋白(Vimentin)、CXCL12、CXCR4蛋白的表达情况;建立小鼠EC移植瘤模型并观察各组小鼠的肿瘤生长情况。结果发现与Control组相比, AMD 3100组和STA处理组细胞增殖活性、克隆数量、迁移和侵袭数以及Vimentin、CXCL12、CXCR4蛋白表达水平降低,细胞凋亡率和E-cadherin蛋白表达水平升高(P<0.05);与STA-H组相比, STA-H+CXCL12组细胞的增殖活性、克隆数量、迁移和侵袭数以及Vimentin、CXCL12、C...     

HIF-2α/Notch3通路介导CoCl_2诱导的乳腺癌MCF-7细胞迁移和侵袭

本研究旨在探究HIF-2α和Notch3在CoCl_2诱导的乳腺癌MCF-7细胞迁移和侵袭中的作用。使用CoCl_2于体外建立化学性低氧模型;采用sh RNA技术沉默MCF-7细胞中HIF-2α和Notch3基因;采用RT-PCR法检测MCF-7细胞中HIF-2α、Notch3和Hey1的m RNA水平;采用Western blot方法检测MCF-7细胞中HIF-2α、Notch3、Hey1、Snail和E-cadherin蛋白的表达水平;采用划痕实验和Transwell实验分别检测CoCl_2诱导的MCF-7细胞迁移和侵袭。结果显示,CoCl_2处理可使MCF细胞中HIF-2α、Notch3、Hey1和Snail蛋白表达水平升高(P0.05),E-cadherin蛋白表达水平下降(P0.05),促进MCF-7细胞迁移和侵袭(P0.05);沉默HIF-2α基因表达可抑制CoCl_2诱导的Notch3和Hey1的m RNA和蛋白表达(P0.05);抑制Notch3基因表达后,CoCl_2诱导的MCF-7细胞迁移和侵袭以及CoCl_2对Snail和E-cadherin蛋白表达的调节随之受到抑制(P0.05)。以上结果表明,在CoCl_2化学性低氧环境下,HIF-2α可通过强化Notch3信号通路,进而导致Snail蛋白水平升高和E-cadherin蛋白水平下降,最终提高乳腺癌MCF-7细胞的迁移和侵袭能力。     

miR-145通过下调PLCε抑制膀胱癌EMT和迁移及其机制研究

目的:探讨miR-145调控PLCε对膀胱癌细胞T24上皮间质转化(EMT)和迁移的影响及可能的分子机制。方法:(1)腺病毒感染T24细胞,划痕实验和Transwell检测细胞的迁移能力;RTPCR、Western blot分别检测PLCε及EMT相关分子的表达;为探究其分子机制,Western blot检测GSK-3β磷酸化(Ser9位点)和Snail的表达情况。(2)利用生物信息学技术预测可能调控PLCε的miRNA,结合文献报道的膀胱癌microRNA表达谱结果筛选出miR-145;转染miR-145 mimics至T24,q PCR检测miR-145、PLCε的表达,Western blot检测PLCε的表达。(3)转染miR-145 mimics,Western blot检测EMT相关分子及p-GSK-3β、Snail;划痕实验、Transwell检测过表达miR-145后细胞的迁移能力。结果:(1)干扰PLCε表达能显著抑制细胞的迁移,同时,使T24细胞中E-cadherin表达上调,N-cadherin和Vimentin表达下调;干扰PLCε后,GSK-3β磷酸化(Ser9位点)水平下降,Snail表达降低。(2)转染miR-145 mimics可使T24细胞中miR-145表达增高,且明显抑制T24细胞中PLCε的表达。(3)在T24中过表达miR-145,细胞迁移能力显著下降,EMT标志分子的表达情况与沉默PLCε结果一致。同时,与阴性对照组相比,转染miR-145 mimics组p-GSK-3β和Snail表达显著减少。结论:PLCε通过GSK-3β/Snail信号通路促进膀胱癌细胞T24发生EMT及迁移,miR-145可以逆转PLCε诱导膀胱癌EMT的发生,从而阻止膀胱癌细胞的迁移。     

肝星形细胞分泌的趋化因子CXCL1在肝癌转归中的作用

该文探讨了人肝星形细胞(hepatic stellate cells,HSC)对肝癌细胞(Hep G2、SMMC-7721)的迁移、侵袭能力和上皮–间质转化(epithelial-msenchymal transition,EMT)的影响及其机制。采用条件培养法培养肝癌细胞,利用细胞划痕和Transwell实验分析肝星形细胞对肝癌细胞的迁移和侵袭作用。Western blot分析肝星形细胞自身及其分泌到培养液中趋化因子CXCL1[chemokine(C-X-C motif)ligand 1]和肝癌细胞的CXCL1受体2—CXCR2(CXCL1 receptor 2)的表达量,以及条件培养下肝癌细胞中p-PI3K、p-AKT、p-GSK-3β和Snail的表达变化。激光共聚焦显微术和Western blot检测肝癌细胞上皮标志物E-cadherin、间质标志物N-cadherin和Vimentin的表达变化。结果显示,在HSC中大量表达并分泌趋化因子CXCL1,而肝癌细胞Hep G2、SMMC-7721中高表达CXCR2。肝癌细胞通过条件培养后,细胞形态改变,细胞黏附下降,细胞迁移和侵袭能力增强,上皮标志物E-cadherin蛋白表达下调、间质标志物N-cadherin蛋白和Vimentin蛋白表达上调,PI3K/AKT信号通路中的关键成员PI3K和AKT磷酸化水平上调,p-GSK-3β和转录因子Snail表达上调。在肝癌细胞条件培养下加入CXCR2受体的特异性抑制剂(SB265610)后,肝癌细胞上皮标志物E-cadherin蛋白表达上调、间质标志物N-cadherin蛋白和Vimentin蛋白表达下调,p-PI3K、p-AKT、p-GSK-3β和Snail的表达下调。以上结果说明,肝星形细胞可能通过CXCL1/CXCR2轴活化PI3K/AKT信号通路并最终促进肝癌细胞上皮–间质转化。     

Cell separation with horizontal cell electrophoresis under near-isopycnic conditions on a “density cushion”

This report describes an improvement made to the horizontal cell electrophoresis methodology. It involves using two liquid layers differing in density to produce an interface described as a "density cushion". The electrophoretic system that employed an anti-convective porous matrix to separate red blood cells (RBC) and charged dyes effectively was found to be unsuitable for some other mammalian cells. The "density cushion" method was found to be more versatile and applicable to studies on the separation of a variety of cell types. The experiments described show the differences between the electrophoretic mobilities of a human eosinophilic leukaemia cell line (Eol-1) and RBC, both with and without the modification of the cell surface properties.     

Cell electrophoresis — a method for cell separation and research into cell surface properties

In this paper, we discuss the application of various methods of cell electrophoresis in research into cell surface properties (analytical methods), and the separation of uniform cell subpopulations from cell mixtures (preparative methods). The emphasis is on the prospects of the development of simplified and versatile methodologies, i.e. microcapillary cell electrophoresis and horizontal cell electrophoresis under near-isopycnic conditions. New perspectives are considered on the use of analytical and preparative cell electrophoresis in research on cell differentiation, neoplastic transformation, cell-cell interactions and the biology of stem cells. Paper authored by participants of the international conference: XXXIV Winter School of the Faculty of Biochemistry, Biophysics and Biotechnology of Jagiellonian University, Zakopane, March 7–11, 2007, “The Cell and Its Environment”. Publication cost was covered by the organisers of this meeting.     

Polarization and Migration of Hematopoietic Stem and Progenitor Cells Rely on the RhoA/ROCK I Pathway and an Active Reorganization of the Microtubule Network

Understanding the physiological migration of hematopoietic progenitors is important, not only for basic stem cell research, but also in view of their therapeutic relevance. Here, we investigated the role of the Rho kinase pathway in the morphology and migration of hematopoietic progenitors using an ex vivo co-culture consisting of human primary CD34⁺ progenitors and mesenchymal stromal cells. The addition of the Rho kinase inhibitor Y-27632 led to the abolishment of the uropod and microvillar-like structures of hematopoietic progenitors, concomitant with a redistribution of proteins found therein (prominin-1 and ezrin). Y-27632-treated cells displayed a deficiency in migration. Time-lapse video microscopy revealed impairment of the rear pole retraction. Interestingly, the knockdown of ROCK I, but not ROCK II, using RNA interference (RNAi) was sufficient to cause the referred morphological and migrational changes. Unexpectedly, the addition of nocodazole to either Y-27632- or ROCK I RNAi-treated cells could restore their polarized morphology and migration suggesting an active role for the microtubule network in tail retraction. Finally, we could demonstrate using RNAi that RhoA, the upstream regulator of ROCK, is involved in these processes. Collectively, our data provide new insights regarding the role of RhoA/ROCK I and the microtubules in the migration of stem cells.     

Expanisns

Biochemical dissection of the “acid-growth” process of plant cell walls led to the isolation of a new class of wall loosening proteins, called expansins. These proteins affect the rheology of growing walls by permitting the microfibril-matrix network to slide, thereby enabling the wall to expand. Molecular sequence analysis suggests that expansins might have a cryptic glycosyl transferase activity, but biochemical results suggest that expansins disrupt noncovalent bonding between microfibrils and the matrix. Recent discoveries of a new expansin family and gene expression in fruit, meristerms and cotton fibers have enlarged our view of the developmental functions of this group of wall loosening proteins.     

酸性磷酸酶法检测体外培养细胞数

利用小鼠成纤维细胞系(NIH3T3)、小鼠骨髓瘤细胞系(SP2/0)、人大肠癌细胞系(LO-VO)和人白血病细胞系(K562),评价酸性磷酸酶(APA)法用于检测体外各类型细胞的增殖和杀伤作用。用直线回归分析光吸收度与每孔活细胞数的关系。结果表明,APA法能准确地反映检测的活细胞数(相关系数均>0.99)。本方法不仅能很好地检测表皮生长因子对细胞的增殖作用,也能够检测顺铂对体外细胞的杀伤作用。结果表明APA法简单、灵敏,可以用于上皮和间质等贴壁和悬浮生长的细胞计数。     

An overview of the KIN1/PAR-1/MARK kinase family

Members of the KIN1/PAR-1/MARK kinase family are conserved from yeast to humans and share a similar primary structural organization. Several kinases of this family appear to be at the crossroads of various biological functions including cell polarity, cell cycle control, intracellular signalisation, microtubules stability and protein stability. Here we present an overview of known roles of KIN1/PAR-1/MARK kinases including pEg3 a newly identified member which is regulated during the cell cycle and is a potential regulator of the cell cycle progression. Some common modes of action can be deciphered for this protein kinase family.     

犬皮肤成纤维细胞的分离、培养及鉴定

目的探索和建立适用于犬皮肤成纤维细胞的体外分离、培养及鉴定的技术方法。方法采用组织贴块培养法和胰蛋白酶、胶原酶Ⅰ联合消化法对犬皮肤成纤维细胞进行体外培养、传代。并对所培养的细胞进行倒置显微镜观察和苏木素-伊红染色,观察成纤维细胞形态,并对培养细胞行波形蛋白免疫荧光染色。结果倒置相差显微镜下可见长梭形细胞生长,苏木素-伊红染色可见细胞呈漩涡状、平行排列,第5代细胞免疫荧光检测波形蛋白(vimentin)表达阳性。结论建立了高效快速分离和稳定培养成纤维细胞的方法,为诱导犬心房纤维化提供了充足的种子细胞。     

A Scalable Approach to Prevent Teratoma Formation of Human Embryonic Stem Cells

As the renewable source of all cell types in the body, human embryonic stem cells (hESCs) hold great promise for human cell therapy. However, one major bottleneck that hinders the clinic application of hESCs is that hESCs remaining with their differentiated derivatives pose cancer risk by forming teratomas after transplantation. NANOG is a critical pluripotency factor specifically expressed in hESCs but rarely in their differentiated derivatives. By introducing a hyperactive variant of herpes simplex virus thymidine kinase gene into the 3′-untranslated region of the endogenous NANOG gene of hESCs through homologous recombination, we developed a safe and highly scalable approach to efficiently eliminate the teratoma risk associated with hESCs without apparent negative impact on their differentiated cell types. As thymidine kinase is widely used in human gene therapy trials and is the therapeutic target of U. S. Food and Drug Administration-approved drugs, our strategy could be effectively applied to the clinic development of hESC-based human cell therapy.     

The plant cell body: a cytoskeletal tool for cellular development and morphogenesis

Summary Certain aspects of cellular behaviour in relation to growth and development of plants can be understood in terms of the cell body concept proposed by Daniel Mazia in 1993. During the interphase of the mitotic cell cycle, the plant cell body is held to consist of a nucleus and a perinuclear microtubule-organizing centre from which microtubules radiate into the cytoplasm. During mitosis and cytokinesis in meristematic cells, and also during the period of growth in post-mitotic cells immediately beyond the meristem, the plant cell body undergoes various characteristic morphological transformations, many of which are proposed as being related to changing structural connections with the actin-based component of the cytoskeleton and with specialized, plasma-membrane-associated sites at the cell periphery. In post-mitotic cells, these transformations of the plant cell body coincide with, and probably provide conditions for, the various pathways of development which such cells follow. They are also responsible, for the acquisition of new cellular polarities. Events in which the plant cell body participates include the formation of a mitotic spindle, phragmoplast, and new cell division wall, the rearrangement of a diffuse type of cell wall growth into tip growth (as occurs, e.g., during the initiation and subsequent development of root hairs), and the growth and division that occurs in reactivated vacuolate cells. If more evidence can be marshalled in support of the existence and properties of the plant cell body, then this concept could prove useful in interpreting the cytological bases of a range of developmental events in plants.Abbreviations CMT cortical microtubule - EMT endoplasmic microtubule - ER endoplasmic reticulum - MF microfilament - MT microtubule - MTOC microtubule-organizing centre - PPB preprophase band (of microtubules) - QC quiescent centre - VSC vesicle supply centre     

Molecular basis for T cell response induced by altered peptide ligand of type II collagen

Mounting evidence from animal models has demonstrated that alterations in peptide-MHC interactions with the T cell receptor (TCR) can lead to dramatically different T cell outcomes. We have developed an altered peptide ligand of type II collagen, referred to as A9, which differentially regulates TCR signaling in murine T cells leading to suppression of arthritis in the experimental model of collagen-induced arthritis. This study delineates the T cell signaling pathway used by T cells stimulated by the A9·I-A(q) complex. We have found that T cells activated by A9 bypass the requirement for Zap-70 and CD3-ζ and signal via FcRγ and Syk. Using collagen-specific T cell hybridomas engineered to overexpress either Syk, Zap-70, TCR-FcRγ, or CD3-ζ, we demonstrate that A9·I-A(q) preferentially activates FcRγ/Syk but not CD3-ζ/Zap-70. Moreover, a genetic absence of Syk or FcRγ significantly reduces the altered peptide ligand induction of the nuclear factor GATA3. By dissecting the molecular mechanism of A9-induced T cell signaling we have defined a new alternate pathway that is dependent upon FcRγ and Syk to secrete immunoregulatory cytokines. Given the interest in using Syk inhibitors to treat patients with rheumatoid arthritis, understanding this pathway may be critical for the proper application of this therapy.