KAI1基因对乳腺癌细胞体外增殖的抑制作用

目的研究KAI1基因对乳腺癌细胞体外增殖的抑制作用。方法应用脂质体法将pCMV-KAI1质粒转染人高转移性人乳腺癌细胞株MDA-MB-231中,免疫印迹方法检测蛋白表达;利用四甲基偶氮唑盐(MTT)法、平板克隆形成实验、体外黏附及侵袭力实验判断细胞增殖能力及黏附、侵袭力的变化。流式细胞术检测细胞生长周期的变化。结果获得了稳定表达KAI1基因的MDA- MB-231乳腺癌细胞克隆。MTT法显示,转染KAI1基因组的集落形成率(25.33%±2.36%)较转染前(43.17%±2.75%)明显降低(P<0.05)。体外黏附及侵袭力实验表明,转染组的细胞黏附侵袭能力低于未转染组和转染空载体组(P<0.05)。流式细胞术显示,转染KAI1后,G_0/G_1期细胞数量增高,从36.78%±0.61%升高至64.00%±7.56%;G_2/M期数量降低,由17.88%±0.76%降至7.63%±0.60%,差异有统计学意义。结论KAI1基因可以抑制乳腺癌细胞的增殖黏附和侵袭能力,并可能通过调节细胞周期来影响细胞的增殖。     

KAI1基因转染ATRA诱导对小细胞肺癌细胞株恶性特征的抑制作用

背景与目的:探讨新抑癌基因KAI1与全反式维甲酸(all-trans-retinoic acid,ATRA)对小细胞肺癌NCI-H446细胞株抑制增殖和诱导分化的作用.材料与方法:用脂质体介导的基因转染方法,借助质粒表达载体(PCMV-NEO-XhoI),将抑癌基因KAI1转入小细胞肺癌NCI-H446细胞中,经G418筛选,获得稳定表达的细胞克隆.用10-6mol/L ATRA作用于转染及未转染KAI1基因的小细胞肺癌NCI-H446细胞株,集落形成率检测细胞体外增殖能力,流式细胞仪进行细胞周期和凋亡分析,间接免疫荧光染色结合流式细胞仪检测转染前后细胞CD82蛋白的表达.免疫组化测定MYC的表达,放射免疫测定LN(层连蛋白)表达.结果:ATRA处理脂质体-KAI1基因转染的小细胞肺癌细胞CD82表达降低,细胞增殖能力下降,凋亡增加,更多的细胞被阻止于G1/G0期,MYC及LN表达下降.结论:抑癌基因KAI1与ATRA对抑制小细胞肺癌NCI-H446细胞株的增殖和促分化有协同作用.     

肿瘤转移抑制基因KAI1对子宫内膜癌细胞增殖、侵袭能力的影响

目的:探讨肿瘤转移抑制基因KAI1基因对子宫内膜癌细胞(AN3CA和HEC-1-B)增殖及侵袭能力的影响。方法:脂质体介导pcDNA3-KAI1质粒转染人子宫内膜癌细胞AN3CA和HEC-1-B,采用免疫印迹法和流式细胞术检测转染前后肿瘤细胞KAI1蛋白的表达,MTT比色法、软琼脂克隆形成实验观察KAI1基因对肿瘤细胞增殖能力的影响,Transwell侵袭实验检测转染前后肿瘤细胞侵袭能力的变化。结果:转染pcDNA3-KAI1质粒后AN3CA和HEC-1-B细胞内和细胞表面均可检测到KAI1蛋白的稳定表达。转染空白质粒组细胞形成克隆数量多体积较大,细胞克隆形成率为(54.2±3.1)%和(52.7±4.3)%,细胞的倍增时间为21.3h和20.1h;基因转染pcDNA3-KAI1质粒组细胞形成克隆数少体积较小,细胞克隆形成率为(37.4±5.1)%和(32.1±3.7)%,细胞的倍增时间为43.7h和45.2h;两组间细胞增殖能力和克隆形成能力比较,差异均有统计学意义(P<0.05)。基因转染组细胞的穿膜细胞数为(91±10.7)/HT、(68±10.8)/HT,而空质粒转染组细胞的穿膜细胞数为(292±11.5)/HT、(219 12.7)/HT,两组细胞比较,侵袭能力亦显著下降(P<0.05)。结论:外源性肿瘤转移抑制基因KAI1有效转染可使子宫内膜癌细胞增殖、侵袭能力均下降,KAI1可能成为子宫内膜癌转移的新治疗靶点。     

KAI1基因转染协同ATRA诱导对肺腺癌细胞株抑制作用的研究

目的 :探讨新抑癌基因KAI1与全反式维甲酸 (all trans retinoicacid ,ATRA)对肺腺癌A5 49细胞株抑制增殖和诱导分化的作用。方法 :用脂质体介导的基因转染方法 ,借助质粒表达载体 (PCMV NEO XhoI) ,将抑癌基因KAI1转入肺腺癌A5 49细胞中 ,经G418筛选 ,获得稳定表达的细胞克隆。用 10 6mol/LATRA作用于转染及未转染KAI1基因的肺腺癌A5 49细胞株 ,MTT法检测细胞体外增殖能力 ,流式细胞仪进行细胞周期和凋亡分析 ,间接免疫荧光染色结合流式细胞仪检测转染前后细胞CD82 蛋白的表达。免疫组化测定myc、基质金属蛋白酶 (MMP 1)的表达 ,放射免疫测定层连蛋白(LN)表达。结果 :ATRA处理KAI1基因转染的肺腺癌细胞CD82 表达降低 ,细胞增殖能力下降 ,凋亡增加 ,更多的细胞被阻止于G1/G0 期 ,myc、MMP 1及LN表达下降 ,比对照组及单纯转染组细胞差异有统计学意义 ,P <0 0 5。结论 :抑癌基因KAI1与ATRA对抑制肺腺癌A5 49细胞株的增殖浸润转移有协同作用。     

TSLC1基因对食管癌细胞EC109增殖与侵袭能力抑制的实验研究

目的:探讨肺癌抑癌基因1(TSLC1)对食管癌细胞株EC109增殖与侵袭转移能力的影响。方法:采用RT-PCR法获得TSLC1基因全长编码区序列,构建pc DNA3.1-TSLC1真核表达载体并稳定转染食管癌细胞株EC109,以MTT法测定细胞增殖水平,以细胞黏附、侵袭与迁移实验分别检测细胞黏附、侵袭与转移能力。结果:成功构建TSLC1真核表达载体,稳定转染EC109细胞后可显著抑制肿瘤细胞的增殖、黏附、侵袭与迁移能力。结论:过表达TSLC1基因对食管癌细胞的恶性生物学特征显示明显的抑制作用,为进一步研究TSLC1在食管癌发生和进展中的作用奠定了实验基础。     

脂质体介导KAI1基因转染对小细胞肺癌NCI-H446细胞株的抑制作用

 目的　探讨新抑癌基因KAI1对小细胞肺癌NCI H4 4 6细胞株抑制增殖和浸润转移的作用。方法　用脂质体介导的基因转染方法 ,借助真核质粒表达载体 (PCMV NEO XhoI) ,将抑癌基因KAI1转入小细胞肺癌NCI H4 4 6细胞中 ,经G4 18筛选 ,获得稳定表达的细胞克隆。观察NCI H4 4 6细胞的生长 ,MTT法检测细胞体外增殖能力 ,流式细胞仪进行细胞凋亡分析 ,间接免疫荧光染色结合流式细胞仪检测转染前后细胞CD82蛋白的表达。免疫组化测定Myc及MMP 1(基质金属蛋白酶 1)的表达 ,放射免疫测定LN(层黏蛋白 )表达。结果　脂质体 KAI1基因转染的小细胞肺癌细胞CD82表达增加 ,细胞增殖能力下降 ,凋亡增加 ,癌基因Myc ,MMP 1及LN表达下降。 结论　抑癌基因KAI1抑制小细胞肺癌NCI H4 4 6细胞株的增殖 ,降低Myc ,MMP 1及LN的表达。     

IGF-1R表达下调抑制肾癌786-0细胞的增殖、迁移、侵袭和细胞周期G1/S期转变

目的:观察小干扰RNA (siRNA)介导的胰岛素样生长因子1受体(IGF-1R)基因沉默对肾癌细胞786-0增殖、迁移、侵袭和细胞周期的影响.方法:采用实时定量PCR(real-time PCR)和蛋白印迹法(West-ern blot)测定转染后肾癌细胞IGF-lR及下游相关产物的表达;采用Cell counting kit-8(CCK-8)检测细胞增殖能力;Transwell实验及划痕实验检测细胞迁移及侵袭能力;流式细胞仪检测细胞凋亡及周期改变.结果:IGF-1R基因的siRNA可有效抑制IGF-1R mRNA及蛋白的表达(P＜0.01);细胞增殖实验结果显示IGF-1R-siRNA转染组增殖能力显著减弱(P＜0.01);Transwell实验及划痕实验结果显示IGF-1R-siRNA转染组侵袭及迁移能力明显降低(P＜0.01);流式细胞术检测到转染后细胞G1期细胞数明显升高,发生G1/S期阻滞(P＜0.05);IGF-1R下游蛋白p-IRS1、p-IRS2、p-SHC水平显著降低.结论:IGF-1R表达下调可以抑制肾癌786-0细胞的生长、增殖、迁移和侵袭的能力,并可以使肾癌786-0细胞G1/S期细胞周期停滞.     

GSTP1基因对人肝癌细胞系HepG2增殖和侵袭能力的影响

目的 探讨过表达/沉默GSTP1基因对人肝癌细胞系HepG2增殖及侵袭能力的影响。 方法 采用腺病毒载体转染人肝癌细胞系HepG2,获得过表达/沉默GSTP1基因的HepG2细胞。实时荧光定量PCR（qPCR）法检测细胞中GSTP1 mRNA表达水平;CCK-8法和Transwell小室法分别检测细胞的细胞活力和侵袭能力;免疫印迹法（Western blot）检测细胞中Akt、mTOR、p-Akt和p-mTOR的蛋白表达。 结果 经腺病毒载体转染后,成功获得过表达/沉默GSTP1基因的HepG2细胞;过表达GSTP1 基因后,HepG2细胞的细胞活力和侵袭能力显著降低（P<0.05）,而沉默GSTP1基因后,HepG2细胞的细胞活力和侵袭能力则显著增高（P<0.05）;过表达GSTP1基因后,p-Akt和p-mTOR的蛋白表达水平显著降低（P<0.05）,而沉默GSTP1基因的结果则相反。 结论 过表达GSTP1基因可抑制HepG2细胞的增殖和侵袭能力,沉默GSTP1基因则促进HepG2细胞的增殖和侵袭能力,其作用机制可能与Akt/mTOR信号通路有关。     

KAI1/CD82通过Wnt/β-catenin通路对肾癌调控机制的研究

目的:检测KAI1/CD82和p-catenin在肾癌组织及细胞中的表达情况,探讨KAI1/CD82通过Wnt/β-catenin通路对肾癌的调控机制.方法:通过Western blotting检测我院近2年收集的30例肾癌及癌旁组织中CD82及β-catenin的表达;构建KAI1/CD82低表达质粒,转染肾透明细胞癌细胞系786-0和OSRC,划痕实验检测细胞迁移能力;CCK-8法检测细胞增殖能力;Transwell检测细胞侵袭能力;Western blotting检测β-catenin、Axin2、GSK-3β的表达.结果:肾癌组织中CD82表达低于癌旁组织,β-catenin的表达高于癌旁组织.PLTHR-SHKAI1质粒转染786-0和OSRC后,肾癌细胞的迁移、增殖、侵袭能力增强,β-catenin表达增高,Axin2、GSK-3β表达降低.结论:KAI1/CD82和β-catenin在肾癌组织中表达负相关,KAI1抑制肾癌细胞的迁移、增殖、侵袭能力;KAI1/CD82通过Wnt/β-catenin通路相关上游蛋白调控肾癌的发生、发展和转移.     

VEGFR-3 siRNA对人结肠癌细胞黏附力和侵袭性的抑制作用

目的:探讨VEGFR-3对人结肠癌细胞黏附力和侵袭性的影响.方法:构建携靶向 VEGFR-3基因siRNA(small interfering RNA)表达载体,转染人结肠癌LoVo细胞, 半定量RT-PCR和Western blotting检测转染前后LoVo细胞VEGFR-3 mRNA和蛋白表达的变化,基质-黏附实验检测细胞转染后的黏附能力,细胞侵袭实验检测转染后肿瘤细胞侵袭性的改变.结果: 携靶向VEGFR-3基因siRNA的表达载体成功构建,RT-PCR检测转染siRNA后LoVo细胞VEGFR-3 mRNA表达水平降低;Western blotting检测转染siRNA后72 h LoVo细胞VEGFR-3蛋白表达下降,其表达相对值由(1.26±0.19)降至(0.39±0.12)(P<0.05).转染siRNA 72 h后LoVo细胞的黏附能力显著下降[(0.626±0.047)vs (0.407±0.029), P＜0.05];LoVo细胞穿膜细胞数(6.38±3.25)明显低于空白对照组(24.82±3.44)、非特异性对照组(23.58±3.73) (P＜0.05).结论:siRNA能够在LoVo细胞中引发RNA干扰效应,下调VEGFR-3基因的表达,进而抑制LoVo细胞的黏附能力和侵袭性.     

乳腺癌转移抑制基因1抑制肿瘤转移的作用机制

乳腺癌转移抑制基因1 (BRMS1)在多种恶性肿瘤细胞中表达降低或缺失,具有明显降低癌细胞侵袭和转移的作用.BRMS1基因通过磷酸肌醇信号及核转录因子-κB(NF-κB)信号通路等调节基因转录和蛋白翻译,还可与mSin3-组蛋白去乙酰化酶(HDAC)复合体、雌激素受体等蛋白相互作用、修复细胞间隙通讯等途径抑制肿瘤细胞的侵袭及转移.BRMS1基因将可能成为有效抑制肿瘤转移基因治疗的新靶点.     

乳腺癌转移抑制基因1抑制肿瘤转移的机制

乳腺癌转移抑制基因1(BRMS1)具有抑制肿瘤细胞转移的能力,可明显减少转移灶的发生,但不影响肿瘤的生长.其作用机制复杂,与细胞间通讯、磷酸肌醇信号转导以及与转录核因子-KB(NF-KB)的相互作用等有关.故探讨BRMS1抑制肿瘤转移的机制,希望用于肿瘤基因治疗.     

Downregulation of osteopontin contributes to metastasis suppression by breast cancer metastasis suppressor 1

Breast cancer metastasis suppressor 1 (BRMS1) inhibits the ability of multiple human and murine cancer cell lines to metastasize to lymph nodes, bones and lungs. Comparison of mRNA expression in metastatic MDA-MB-435 human carcinoma cells (435) and metastasis-suppressed BRMS1 transfectants (435/BRMS1) showed a marked (>90%) reduction of osteopontin (OPN) mRNA and protein expression in BRMS1-overexpressing cells. OPN expression is associated with disease progression in patients, with higher levels of OPN produced by cancer cells associated with poorer patient survival. Furthermore, OPN has been suggested to promote survival of cancer cells in response to stress, although the mechanisms by which this may occur remain poorly understood. This study tested the hypothesis that re-expression of OPN in metastasis-suppressed 435/BRMS1 cells would reverse metastasis suppression and confer protection from stress-induced apoptosis. A stable pooled population of OPN overexpressing 435/BRMS1 cells was created (435/BRMS1/OPN). OPN re-expression did not affect in vitro cell growth rates; however, increased anchorage independent growth/survival and protection from hypoxia-induced apoptosis was observed (p < 0.05). In vivo, OPN re-expression in BRMS1 transfected cells did not affect in vivo primary tumor growth but did increase the incidence of spontaneous metastasis to lymph nodes and lungs in mice. These novel findings suggest that OPN downregulation by BRMS1 may be responsible, at least in part, for BRMS1-mediated metastasis suppression by sensitizing cancer cells to stress induced apoptosis. These studies clarify one mechanism by which BRMS1 can suppress metastasis.     

MicroRNA-182 downregulates metastasis suppressor 1 and contributes to metastasis of hepatocellular carcinoma

ABSTRACT: BACKGROUND: miR-182 is one of the most significantly up-regulated miRNAs in hepatocellular carcinoma (HCC). Metastasis suppressor 1 (MTSS1), one target gene of miR-182, plays an important role in the metastasis of cancers. However, it remains unclear that the exact function and mechanism of miR-182 and MTSS1 in HCC. METHODS: miR-182 expression was tested in 86 cases of paired HCC and normal tissues by real-time PCR and the relationships between miR-182 expression and clinicopathological parameters were analyzed. The expression of MTSS1 was evaluated by immunohistochemistry and western blot in the above tissues and its correlation with miR-182 expression was analyzed. Moreover, western blot and invasion assay were performed after transfection of pre-miR-182 or anti-miR-182 in HCC cell lines. In addition, luciferase assay and rescue experiment were performed in HCC cell lines. RESULTS: Compared with normal tissue, miR-182 was up-expression and MTSS1 was down-expression in HCC tissues. Moreover, the over-expression of miR-182 was correlated with intrahepatic metastasis (p=0.034) and poor prognosis (p=0.039) of HCC patients. There was a negative correlation between miR-182 and MTSS1 expression both in HCC tissues (r =-0.688, p<0.01) and HCC cell lines (r =-0.931, p=0.021). Furthermore, the up-regulation of miR-182 resulted in the down-expression of MTSS1 and increased invasive potential of HUH-1, and reverse results were also confirmed when the expression of miR-182 was inhibited. In addition, the results of luciferase assay demonstrated the targeted regulation of miR-182 on MTSS1. CONCLUSIONS: miR-182 could promote metastasis of HCC through the down-regulation of its target gene MTSS1. miR-182 and MTSS1 were potential prognostic markers and/or therapeutic targets in HCC.     

GAP-independent functions of DLC1 in metastasis

Metastases are responsible for most cancer-related deaths. One of the hallmarks of metastatic cells is increased motility and migration through extracellular matrixes. These processes rely on specific small GTPases, in particular those of the Rho family. Deleted in liver cancer-1 (DLC1) is a tumor suppressor that bears a RhoGAP activity. This protein is lost in most cancers, allowing malignant cells to proliferate and disseminate in a Rho-dependent manner. However, DLC1 is also a scaffold protein involved in alternative pathways leading to tumor and metastasis suppressor activities. Recently, substantial information has been gathered on these mechanisms and this review is aiming at describing the potential and known alternative GAP-independent mechanisms allowing DLC1 to impair migration, invasion, and metastasis formation.     

乳腺癌转移抑制基因作用机制

乳腺癌转移抑制基因（BRMS1）在人乳腺癌、黑色素瘤、膀胱癌、卵巢癌、嗜铬细胞瘤中具有抑制肿瘤细胞转移的能力，可明显减少转移灶的发生，作用机制复杂多样而又非典型，成为研究抑制肿瘤转移的新靶点。     

乳腺癌转移抑制基因作用机制

乳腺癌转移抑制基因(BRMS1)在人乳腺癌、黑色素瘤、膀胱癌、卵巢癌、嗜铬细胞瘤中具有抑制肿瘤细胞转移的能力,可明显减少转移灶的发生,作用机制复杂多样而又非典型,成为研究抑制肿瘤转移的新靶点。     

Suppression of murine mammary carcinoma metastasis by the murine ortholog of breast cancer metastasis suppressor 1 (Brms1)

The murine ortholog (Brms1) of human breast cancer metastasis suppressor 1 shares 95% identity to the human metastasis suppressor, BRMS1, in amino acid structure. We tested Brms1 for suppression of metastasis of mouse mammary carcinoma cell line 4T1 in syngenic BALB/c mice, using orthotopic (mammary fat pad) injection as well as intravenous injection. As observed for BRMS1, transfection with Brms1 did not inhibit 4T1 primary tumor formation, but significantly suppressed lung colonization. We also show that Brms1 protein interacts with histone deacetylases, indicating involvement of Brms1 in murine Sin3-HDAC complex, like its human counterpart. Thus, because of similarities with its human ortholog, the results suggest that Brms1 will be useful as a model for studying mechanism of action of BRMS1.     

Kiss-1 基因与恶性肿瘤转移

Kiss-1基因是与人类多种恶性肿瘤发生发展相关的肿瘤转移抑制基因,在恶性肿瘤的浸润和转移过程中发挥重要作用.Kiss-1基因与黑色素瘤、乳腺癌、胃癌、食管癌及分化型甲状腺癌等恶性肿瘤的转移密切相关,但其作用机制尚未完全清楚.通过检测恶性肿瘤患者肿瘤组织中Kiss-l基因的表达情况,将有助于恶性肿瘤患者的治疗和预后评估.