TSA对人肝癌细胞SMMC-7721的抑制作用及其机制

目的：研究去乙酰化转移酶抑制剂TSA对肝癌细胞SMMC-7721的作用及其机理。方法：利用细胞计数,流式细胞仪分析细胞凋亡及细胞周期,Tunel试验研究TSA对肝癌细胞SMMC-7721的作用;利用western研究TSA对肝癌细胞蛋白表达的影响。结果：TSA可明显抑制肝癌细胞SMMC-7721的生长,并可诱导细胞凋亡。可阻滞肝癌细胞SMMC-7721细胞周期于G0/G1期。可增加p53,p21,bax等基因的表达,降低BCL-2的表达。结论：去乙酰化转移酶抑制剂TSA可明显抑制肝癌细胞SMMC-7721的生长并诱导其凋亡,其主要通过调控一些肿瘤相关基因的表达起作用。     

人参皂苷Rg3抗人肝癌细胞株侵袭和转移的实验研究

目的:探讨人参皂苷Rg3抗人肝癌细胞侵袭和转移的作用及其相关机制。方法:选择人类肝癌细胞株SMMC-7721细胞和建株人脐静脉内皮细胞株ECV304作为研究对象,通过细胞抑制实验(MTT法)、细胞粘附试验和免疫组化方法系统地观察人参皂苷Rg3体外对SMMC-7721细胞及ECV304细胞生长的抑制作用、SMMC-7721细胞与纤维粘连蛋白(FN)粘附以及表达nm23、CD44、VEGF基因蛋白的影响。结果:人参皂苷Rg3能够显著地抑制肝癌细胞株SMMC-7721细胞及内皮细胞株ECV304的生长,抑制SMMC-7721细胞与FN粘附及CD44、VEGF的表达,而增强nm23基因的表达。结论:人参皂苷Rg3具有抗人肝癌细胞侵袭和转移的作用,机制可能与其能够抑制肝癌细胞侵袭活力、调节与肝癌细胞侵袭与转移密切相关的基因表达和抗肿瘤血管形成有关。     

Survivin反义寡核苷酸对肝癌细胞增殖和凋亡的影响

目的:观察Survivin反义寡核苷酸对SMMC-7721细胞增殖、凋亡的影响。方法:设计合成特异性Survivin反义寡核苷酸,转染肝癌SMMC-7721细胞,MTT法测定Survivin ASODN对细胞增殖抑制情况的影响,FCM法检测对细胞周期、凋亡及Survivin蛋白表达的影响。结果:Survivin ASODN可抑制SMMC-7721细胞的生长增殖,并呈浓度和时间依赖性。ASODN转染组可诱导SMMC-7721细胞凋亡(P<0.01),细胞周期阻滞于G2/M期(P<0.05)。ASODN转染组Survivin蛋白表达水平显著降低(P<0.01)。结论:Survivin ASODN能下调SMMC-7721细胞Survivin表达,并可抑制其增殖并诱导凋亡。     

反义寡核苷酸抑制survivin基因表达及肝癌细胞生长的研究

目的:采用反义寡核苷酸抑制肝癌细胞中survivin基因的表达,研究其对肝癌细胞生长的作用.方法:采用脂质体介导survivin反义寡核苷酸转染人肝癌细胞株SMMC-7721细胞,Western blot及原位杂交方法检测survivin蛋白及mRNA表达,流式细胞仪检测凋亡细胞比率,检测转染前后细胞贴壁率变化,并绘制细胞生长曲线.结果:survivin反义寡核苷酸转染后,肝癌细胞survivin蛋白及mRNA表达均显著降低,细胞贴壁率显著降低,细胞增殖活性明显受抑,细胞凋亡率显著增加.结论:survivin反义寡核苷酸转染可以有效降低细胞内survivin基因的表达,诱导细胞发生凋亡,抑制肝癌细胞生长.     

曲古霉素A对肺腺癌细胞株NCI-H1299增殖的抑制作用及其机制

背景与目的：曲古霉素A（trichostatin A,TSA）是具有组蛋白去乙酰化酶（histone deacetylases,HDAC@强效非竞争性抑制剂,对血液系统肿瘤和实质性肿瘤均有较强的生长抑制作用。本文观察HDACs抑制剂TSA对体外培养的肺腺癌NCI-H1299细胞株的增殖、凋亡和周期以及相关基因表达的影响,并探讨其可能的作用机制。方法：MTT法检测不同浓度（0.1、0.2、0.4、2.0μmol/L@的TSA对人肺腺癌NCI-H1299细胞株体外增殖的影响,流式细胞术检测药物处理后细胞周期及凋亡率的变化;Western blot法检测细胞内组蛋白H4乙酰化水平的变化;Real-time PCR检测NCI-H1299细胞内p21、CyclinB1、Bcl-2和Bax的基因表达。结果：TSA能明显抑制NCI-H1299细胞的体外生长,其抑制作用呈明显的剂量和时间依赖性。TSA诱导后,流式细胞术检测结果显示细胞阻滞于G2/M期,细胞凋亡增加。TSA可明显提高NCI-H1299细胞内组蛋白H4的乙酰化水平,诱导p21和Bax的mRNA表达增加,同时抑制Bcl-2和CyclinB1表达。结论：TSA可通过诱导细胞凋亡及阻滞细胞周期而发挥体外抗肺腺癌细胞生长的作用,其机制可能与组蛋白乙酰化水平的提高以及调控相关基因p21、Bax、Bcl-2和CyclinB1的表达变化有关。     

珠子参体外诱导人肝癌细胞凋亡效应及机制研究

目的观察珠子参体外诱导人肝癌细胞凋亡效应并初探其分子机制。方法体外细胞培养采用人肝癌细胞株SMMC-7721,分为对照(BL)组、珠子参(PJ)组、二甲基亚砜(DMSO)组及5-FU组,采用电镜观察作用后肝癌细胞超微结构改变;流式细胞仪检测肝癌细胞周期和凋亡率;RT-PCR法检测癌基因c-myc、c-fos和抑癌基因p53、p21表达的变化。结果与对照组比较,电镜下珠子参组SMMC-7721细胞染色质浓缩,分解成大小不一有膜包绕团块,内含有新月形DNA物质及细胞器,形成凋亡小体;周期分析可见G0/G1期细胞阻滞,阻止了细胞向S期的转换,并引起细胞凋亡,凋亡率达38.34%;RT-PCR半定量分析珠子参能降低癌基因c-myc表达(P<0.05),增高抑癌基因p53和p21表达(P<0.05)。结论珠子参能诱导人肝癌细胞SMMC-7721凋亡,部分作用机制可能与阻滞细胞停留在G0/G1,降低癌基因c-myc和c-fos表达,增高抑癌基因p53和p21表达有关。     

薏苡仁油注射液对人体肝癌SMMC-7721细胞株体外抗肿瘤作用及机制研究

目的：研究薏苡仁油注射液（KLT）对人体肝癌SMMC-7721的体外抗肿瘤作用及机制。方法：在人肝癌SMMC-7721细胞模型上采用CCK-8细胞增殖试验、划痕试验、Transwell小室穿膜试验、Matrigel克隆形成试验观察KLT对细胞增殖、迁移及侵袭的影响;应用流式细胞术检测KLT对肿瘤细胞周期及细胞凋亡的影响;Western blot检测KLT对肿瘤细胞中目的基因的表达情况。结果：经KLT作用后的人肝癌细胞生长、迁移及侵袭功能被抑制;流式细胞术检测发现KLT处理的肝癌细胞阻滞于G2/M期,细胞晚期凋亡较明显;KLT上调了cyclin B1的表达,下调了cyclin D1、cyclin E的表达。结论：KLT在体外对肝癌细胞具有良好的抗肿瘤活性,其作用机制可能与其诱导的细胞周期阻滞、细胞凋亡、抑癌基因的上调、癌基因的下调有关。     

棘霉素对肝癌SMMC7721细胞凋亡相关基因影响的研究

目的:探讨棘霉素诱导肝癌SMMC7721细胞的凋亡作用及对转录因子Twist、p53、Survivin和hTERT(人端粒酶)基因的影响.方法:采用MTT法测定棘霉素对肝癌细胞的生长抑制率;半定量逆转录聚合酶链反应(RT-PCR)检测与肝癌的发生和转移密切相关的转录因子Twist,与细胞增殖和凋亡联系紧密的p53、Survivin和hTERT的mRNA表达水平的改变;利用Western blot方法分析棘霉素治疗后上述基因的蛋白表达情况.结果:体外实验证实,棘霉素浓度＞10.0 ng/mL各组对细胞的生长抑制均显著增加,P<0.05,随棘霉素药物浓度增加,细胞抑制率明显增大.棘霉素抑制肝癌细胞株SMMC7721的作用呈剂量-时间依赖性. RT-PCR 方法证实,随着棘霉素剂量的增加,肝癌SMMC7721细胞株中Twist、Survivin和hTERT mRNA表达水平逐渐下调,P<0.01,p53 mRNA表达水平微弱上调,P<0.05.Western blot检测显示,Twist、 Survivin和hTERT蛋白的表达量呈递减趋势,P<0.01,p53蛋白的表达微弱上调,P<0.01.结论:随着棘霉素剂量的增加,细胞凋亡率显著增加.棘霉素能够抑制与肝癌生长密切相关基因的Twist、Survivin和hTERT mRNA表达,促进p53 mRNA表达上调,相应蛋白的表达呈下调和上调.棘霉素可能通过抑制肝癌细胞的生长、转移和促进肝癌细胞的凋亡起到抑制肿瘤生长的作用.     

多烯紫杉醇抑制SMMC-7721肝癌细胞的研究

目的探索多烯紫杉醇对在体和离体SMMC-7721肝癌的生长抑制作用及其机制.方法(1)将SMMC-7721肝癌细胞种植于培养皿,贴壁后给予不同浓度的多烯紫杉醇作用24小时,10天后观察多烯紫杉醇对集落形成率的抑制作用;(2)多烯紫杉醇作用于SMMC-7721肝癌细胞24小时后,利用电子显微镜观察细胞凋亡的形态学特征,用流式细胞仪测定细胞周期的变化;(3)制备SMMC-7721肝癌荷瘤鼠模型,观察多烯紫杉醇诱导对在体SMMC-7721肝癌生长曲线和相对生长速率的影响.结果(1)多烯紫杉醇对离体和在体SMMC-7721肝癌细胞生长具有明显抑制作用,并且存在剂量依赖性;(2)多烯紫杉醇可以通过将肝癌细胞阻滞于G2-M期来发挥抗癌作用.结论多烯紫杉醇通过将肝癌细胞阻滞于G2-M期并且诱导肝癌细胞凋亡来发挥抗癌作用,是很有潜力的抗肝癌药物.     

重组腺病毒介导突变型p27基因转移对肝癌细胞SMMC-7721生长的影响

 目的 探讨突变型p27基因（p27mt）对肝癌细胞SMMC-7721的细胞增生和凋亡的调节作用。方法 利用重组体腺病毒Ad-p27mt转染培养的人肝癌细胞SMMC-7721，用3H -TdR掺入法检测细胞增生；流式细胞术、DNA片段分析法、TUNEL法检测细胞凋亡。结果 重组体腺病毒Ad-p27mt在MOI≥ 50时， 可达到100 %的转导效率。Ad-p27mt转染肝癌细胞后，3H -TdR掺入检测发现细胞增生抑制；流式细胞术检测在G1期前出现亚二倍体凋亡峰；细胞DNA抽提电泳后发现凋亡特征性梯带。Ad-p27mt组及空白对照组TUNEL法检测凋亡指数分别为58.6±4.3及4.5±1.6，差异有统计学意义（P＜0.01）。结论 重组腺病毒介导的p27mt基因转移可抑制肝癌SMMC-7721细胞增生并诱导其凋亡。     

The histone deacetylase inhibitor trichostatin A induces cell cycle arrest and apoptosis in colorectal cancer cells via p53-dependent and -independent pathways

Many chemotherapeutic agents induce apoptosis via a p53-dependent pathway. However, up to 50% of human cancers have p53 mutation and loss of p53 function. Histone deacetylase inhibitors (HDACIs) are emerging as a potentially important new class of anticancer agents. Here, we report that, Trichostatin A (TSA), a pan-HDAC inhibitor, could induce G2/M cell cycle arrest and apoptosis in both colorectal cancer cell lines with wild-type p53 (HT116 cells) and mutant p53 (HT29 cells), although HCT116 cells had more apoptotic cells than HT29 cells. TSA induces apoptosis in both cell lines via the mitochondrial pathway as indicated by decrease of the mitochondrial membrane potential (MMP) and activation of caspase-3. Additionally, TSA induces expression of the pro-apoptotic protein Bax and decreases the expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL in both cell lines. Bax knockdown by siRNA significantly impaired TSA-induced apoptosis in both cell lines. These data suggest that TSA induces G2/M cell cycle arrest and Bax-dependent apoptosis in colorectal cancer cells (HCT116 cells and HT29 cells) by both p53-dependent and -independent mechanisms. However, cells with normal p53 function are more sensitive to TSA-induced apoptosis.     

TRICHOSTATIN A INHIBITS PROLIFERATION, INDUCES APOPTOSIS AND CELL CYCLE ARREST IN HELA CELLS

Objective： The histone deacetylase inhibitors （HDACIS） have been shown to inhibit cancer cell proliferation, stimulate apoptosis, an induce cell cycle arrest. Our purpose was to investigate the antiproliferative effects of a HDACI, trichostatin A （TSA）, against human cervical cancer cells （HeLa）. Methods： HeLa cells were treated in vitro with various concentrations of TSA. The inhibitory effect of TSA on the growth of HeLa cells was measured by MTT assay. To detect the characteristic of apoptosis chromatin condensation, HeLa cells were stained with Hoechst 33258 in the presence of TSA. Induction of cell cycle arrest was studied by flow cytometry. Changes in gene expression of p53, p21wafl and p27Kipl were studied by semiquantitative RT-PCR. Results： TSA inhibited cell growth in a time- and dose-dependent manner. Hoechst 33258 staining assay showed that TSA induced apoptosis. Cell cycle analysis indicated that treatment with TSA decreased the proportion of cells in S phase and increased the proportion of cells in G0/G1 and/or G2/M phases of the cell cycle. This was concomitant with overexpression of genes related to malignant phenotype, including an increase in p53, p21wall and p27Kipl. Conclusion： These results suggest that TSA is effective in inhibiting growth of HeLa cells in vitro. The findings raise the possibility that TSA may prove particularly effective in treatment of cervical cancers.     

Curcumin induces apoptosis involving bax/bcl-2 in human hepatoma SMMC-7721 cells

Curcumin is a major active component of Curcuma aromatica salisb, which has been shown to inhibit proliferation of a wide variety of tumor cells. In this study, the molecular mechanisms of curcumin inducing apoptosis in human hepatoma SMMC-7721 cells were examined. We find that curcumin inhibits the growth of SMMC-7721 cells significantly in a concentration-depenent manner, with typical apoptotic morphological changes of cellular nuclei. Annexin-V/PI double staining detected by flow cytometry and expression of the relative apoptotic proteins (Bax, Bcl-2 and caspase-3) revealed a strong apoptosis-inducing competent of curcumin in SMMC-7721 cells. Curcumin increased the expression of bax protein while decreasing that of bc1-2 protein significantly. The results suggest that curcumin induction of apoptosis involves modulation of bax/bcl-2 in SMMC-7721 cells and provide a molecular basis for the development of naturally compounds as novel anticancer agents for human hepatomas.     

Induction and superinduction of growth arrest and DNA damage gene 45 (GADD45) alpha and beta messenger RNAs by histone deacetylase inhibitors trichostatin A (TSA) and butyrate in SW620 human colon carcinoma cells

Histone deacetylase (HDAC) inhibitors such as trichostatin (TSA) and butyrate have been shown to inhibit cancer cell proliferation, induce apoptosis and regulate the expression of genes involved in cell cycle. Although the precise mechanism underlying HDAC inhibitor-induced cell growth arrest is not fully understood, induction of cell cycle related genes such as p21(cip/waf), is thought to be important. Here we showed that in the SW620 human colon cancer cell line, TSA and butyrate induced the growth arrest and DNA damage gene 45alpha (GADD45alpha) and GADD45beta. Furthermore, GADD45beta and p21(cip/waf) messenger RNA were induced in the absence of protein synthesis, indicating that both genes were immediate target genes for TSA. Cyclohexamide and TSA super-induced the expression of GADD45alpha and beta, but not p21(cip/waf). Interestingly while mitogen-activated kinase (MEK) inhibitor PD98059 and p38 kinase inhibitor SB242235 were unable to affect GADD45 induction, two serine/threonine protein kinase inhibitors (H7 and H8) as well as curcumin completely blocked the super-induction. Concomitant to the inhibition of GADD45 induction, H7 and H8 also blocked TSA-induced apoptosis. Taken together, these results suggest that GADD45 induction may play important role in TSA-induced cellular effects.     

人剪切修复基因XPD转染对人肝癌细胞SMMC-7721的生物学影响

目的 将人剪切修复基因XPD稳定转染人SMMC-7721肝癌细胞,观察转染后细胞内野生型p53、XPD、周期素依赖性蛋白激酶(CDK)7、c-myc等基因表达的变化以及对细胞生长的影响,探讨野生型XPD基因与p53、CDK7、c-myc的相互作用及细胞凋亡机制.方法 将表达绿色荧光蛋白并含有人类全长野生型XPD的pEGFP-N2-XPD重组体质粒稳定转染人SMMC-7721肝癌细胞中,选择培养基筛选单克隆稳定转染重组质粒的人SMMC-7721肝癌细胞(SMMC-7721-pEGFP-N2-XPD)和稳定转染空载质粒的人SMMC-7721肝癌细胞(SMMC.7721-pEGFP-N2),并将人SMMC-7721肝癌细胞作为空白对照,利用荧光显微镜观测绿色荧光蛋白表达,用逆转录-聚合酶链反应(RT-PCR)、Westem blot法检测转染XPD基因后细胞内XPD、p53、CDK7、c-myc的表达量变化,并用细胞增殖力检测(MTT)法及流式细胞仪分别检测细胞增殖及凋亡和细胞周期变化.结果 ①免疫荧光显微镜下,SMMC.7721.pEGFP.N2.XPD和SMMC-7721-pEGFP-N2细胞中观察到绿色荧光蛋白表达,说明pEGFP-N2-XPD重组质粒和pEGFP-N2空载质粒成功转染.②RT-PCR检测:SMMC-7721-pEGFP-N2-XPD中p53 mRNA、XPD mR-NA表达量与SMMC-7721-pEGFP-N2和SMMC-7721相比均明显增高(P<0.01),CDK7 mRNA、c-myc mRNA在SMMC-7721-pEGFP-N2-XPD的表达量比两对照组明显降低(P<0.01),而两对照组各个基因的表达没有明显差异(P>0.05).③Western blot检测:SMMC-7721-pEGFP-N2-XPD细胞的p53、XPD蛋白表达最较两对照组升高(P<0.01),CDK7、c-myc的蛋白相对表达量比两对照组降低(P<0.01),两对照组差异没有统计学意义(P>0.05).④M1Tr检测:SMMC-7721-pEGFP-N2-XPD的细胞增殖力较对照组减弱(P<0.05),两对照组筹异没有统计学意义(P>0.05).⑤流式细胞仪检测:SMMC-7721-pEGFP-N2-XPD细胞进入s期出现障碍,停滞在G1期的细胞增多.结论 将XPD成功稳定转染到人SMMC-7721肝癌细胞中,XPD、p53在转录和蛋白水平的表达明显升高,CDK7、c-myc表达明显降低,野生型XPD基因的过表达可能抑制CDK7、c-myc表达,改变细胞周期,并促进p53抑制肝癌细胞增长,促进细胞凋亡.     

Cell cycle arrest and lytic induction of EBV-transformed B lymphoblastoid cells by a histone deacetylase inhibitor, Trichostatin A

Latent infection of the Epstein-Barr virus (EBV) is strongly associated with the pathogenesis of several human tumor types. The restricted expression of the latent EBV antigens is critical for EBV-associated tumors to escape from immune surveillance. EBV lytic replication can be triggered by various treatments and the induced lytic genes cause strong cytotoxic T lymphocyte (CTL) responses. Histone acetylation or deacetylation is associated with chromatin remodeling and regulates gene expression. Histone deacetylase (HDAC) inhibitors affect cell cycle progression as well as gene expression in a wide variety of transformed cells. We examined whether an HDAC inhibitor, TSA, can affect cell cycle progression and induce EBV lytic replication in EBV-transformed lymphoblastoid cell lines (LCLs). TSA caused cell cycle arrest at low concentrations and induced apoptosis at higher (>300 nM) concentrations in the LCLs and EBV negative BJAB cells. To clarify the underlying mechanism of TSA-induced cell cycle arrest, expression of cell cycle regulatory factors was examined by RNase protection assay and Western blot analysis. Following TSA treatment, a reduced expression of cyclin D2 and an induction of p21 may have played an essential role for G1 arrest in LCLs, while p21 induction might have arrested BJAB cells in G1 phase. A Cdk inhibitor, p57, was increased by 300 nM TSA in both LCLs and BJAB cells, indicating its role in apoptosis. Moreover, immunofluorescene assay and Western blotting showed that TSA induced EBV lytic replication in LCL cells. These results suggest that TSA may exert an enhanced anti-tumor effect for EBV-associated tumors not only by inducing a cell cycle arrest and apoptosis, but also by triggering an EBV lytic cycle.     

Antitumor activity of histone deacetylase inhibitor trichostatin A in osteosarcoma cells

Background: Histone deacetylase (HDAC) inhibitors have been reported to induce cell growth arrest,apoptosis and differentiation of tumor cells. The present study aimed to examine the effects of trichostatin A(TSA), one such inhibitor, on the cell cycle, apoptosis and invasiveness of osteosarcoma cells. Methods: MG-63 cells were treated with TSA at various concentrations. Then, cell growth and apoptosis were determinedby 3-(4, 5-dimethyl-2-thiazolyl)-2H-tetrazolium bromide (MTT) and TUNEL assays, respectively; cell cyclingwas assessed by flow cytometry; invasion assays were performed with the transwell Boyden Chamber system.Results: MTT assays revealed that TSA significantly inhibited the growth of MG-63 cells in a concentrationand time dependent manner. TSA treated cells demonstrated morphological changes indicative of apoptosisand TUNEL assays revealed increased apoptosis of MG-63 cells after TSA treatment. Flow cytometry showedthat TSA arrested the cell cycle in G1/G2 phase and annexin V positive apoptotic cells increased markedly. Inaddition, the invasiveness of MG-63 cells was inhibited by TSA in a concentration dependent manner. Conclusion:Our findings demonstrate that TSA inhibits the proliferation, induces apoptosis and inhibits invasiveness ofosteosarcoma cells in vitro. HDAC inhibitors may thus have promise to become new therapeutic agents againstosteosarcoma.     

塞来昔布抑制肝癌细胞株增殖及其机制的实验研究

目的:研究特异性环氧化酶-2(COX-2)抑制剂塞来昔布对人肝癌细胞株SMMC-7721是否有抑制增殖、诱导凋亡作用并初步探讨其作用机制。方法:采用四氮唑盐比色法(MTT法)观察不同浓度的塞来昔布作用后细胞增殖活力改变;流式细胞仪检测细胞凋亡百分率及细胞周期变化;免疫组化观察Bcl-2蛋白和Bax蛋白表达情况。结果:MTT法显示随着塞来昔布浓度和作用时间增加,细胞增殖抑制率上升;流式细胞仪测定空白对照组未见明显凋亡峰,塞来昔布组出现凋亡峰,凋亡率随着时间及药物浓度变化而变化,二者呈正相关;免疫组化显示经塞来昔布干预后,凋亡蛋白Bax表达增加,而Bcl-2表达减少,并随时间和药物浓度变化而明显。结论:塞来昔布抑制SMMC-7721细胞增殖,促进SMMC-7721细胞凋亡,并呈剂量和时间依赖性。其作用机制之一可能是通过减少Bcl-2的表达,增加Bax的表达,从而启动细胞凋亡途径。     

曲古抑菌素A抑制人脑肿瘤细胞增殖及提高p21和p27蛋白表达

背景和目的：研究提示组蛋白乙酰化酶抑制剂曲古抑菌素A能诱导细胞凋亡,本研究拟探讨曲古抑菌素A对人脑肿瘤细胞的杀伤作用和机制。材料和方法：选用两种人脑肿瘤细胞株,一株为p53突变型的人胶质瘤细胞株T98G,另一株为p53野生型的人神经母细胞瘤细胞株SKNSH;采用SRB细胞毒测定方法检测TSA作用后肿瘤细胞的增殖状态,用琼脂糖凝胶DNA电泳和流式细胞仪定性和定量分析肿瘤细胞凋亡情况,应用Western印迹分析TSA作用前后,肿瘤细胞中高度乙酰化的组蛋白H3,H4,内源性p53蛋白,乙酰化p53蛋白,以及细胞周期相关蛋白p21,p27的变化。结果：TSA在纳摩尔级浓度即能有效抑制肿瘤细胞增殖,并引起高度乙酰化的组蛋白分子H3和H4集聚;用320nM的TSA作用肿瘤细胞24小时,即发生显著的肿瘤细胞凋亡;TSA刺激肿瘤细胞48小时内,p21和p27蛋白表达显著增强,其中p21蛋白水平在4小时后时即明显升高,8小时达高峰;p27蛋白水平升高发生在8小时后,而内源性p53蛋白水平和乙酰化的p53蛋白水平未发生变化。结论：TSA在体外能有效抑制对传统化疗耐药的人脑肿瘤细胞生长,其抗肿瘤生长机理可能是通过上调p21和p27蛋白水平实现的,而不受内源性p53基因状态和蛋白改变的影响。