二甲基胂酸抑制胃癌细胞增殖的研究

目的:探讨二甲基胂酸(DMAA)对SGC7901胃癌细胞增殖的抑制作用及其可能的机制.方法:依次用5,10,15,20,25,30mmol/L二甲基胂酸处理培养的SGC7901胃癌细胞24 hrs,在5 mmol/L和10 mmol/L的浓度下分别处理6,12,18.24,30,36,42,48hrs,用MTT计数法测定DMAA对肿瘤细胞增殖的抑制率,用激光共聚焦显微镜检测细胞形态变化以及用DNA凝胶电泳检测细胞凋亡.结果:DMAA在不同浓度下对肿瘤细胞的抑制作用呈现典型的双曲线,即随着浓度的增加DMAA对胃癌细胞的抑制率不断增加并逐渐趋于稳定;在形态学上DMAA在低浓度下引起胃癌细胞的胞膜出泡、核固缩、染色体断裂和凋亡小体等典型的细胞凋亡的变化,而在高浓度下主要引起细胞坏死;DNA凝胶电泳结果显示,在低浓度DMAA作用下胃癌细胞DNA呈现细胞凋亡的梯状带型,而在高浓度下梯状带型则消失.结论:DMAA抑制胃癌细胞的增殖,其在低浓度时能有效诱导胃癌SGC 7901细胞凋亡,而在高浓度时使胃癌细胞坏死而死亡.     

肿瘤血管导向性干扰素IFN-α2a-NGR与5-氟尿嘧啶联合应用对A549细胞增殖的影响

目的:观察重组蛋白肿瘤血管导向性干扰素IFN-α2a-NGR与化疗药物5-氟尿嘧啶联合使用在体外对人非小细胞肺癌细胞株A549的作用,为IFN-α2a-NGR的临床实验设计提供实验依据。方法:不同浓度的肿瘤血管导向性干扰素IFN-α2a-NGR、5-氟尿嘧啶单独及联合作用于细胞株A549,通过MTT法检测单药及联合用药对细胞增殖的影响,经AnnexinⅤ-FITC细胞凋亡检测试剂盒染色、流式细胞术检测细胞凋亡情况,荧光显微镜观察药物作用的细胞形态。结果:IFN-α2a-NGR与5-氟尿嘧啶联合作用于A549细胞株时,其细胞增殖抑制率、细胞凋亡率均较单独作用时高,具有统计学显著性差异(P<0.05);荧光显微镜观察可见药物作用后细胞形态改变。结论:肿瘤血管导向性干扰素IFN-α2a-NGR与5-氟尿嘧啶联合使用具有协同抑制肿瘤细胞增殖的作用。     

STAT2的小分子干扰RNA抑制HeLa细胞增殖

新近研究发现STAT2基因具有致瘤性.前期研究发现:多种肿瘤组织和细胞系高表达STAT2,因此为进一步研究STAT2基因在肿瘤发生发展中的功能,利用RNA基因沉默技术,降低STAT2基因在宫颈癌HeLa细胞系中的内源表达水平,采用XTT实验、软琼脂集落形成实验以及裸鼠体内成瘤实验等研究策略,发现沉默STAT2基因可抑制...     

丹皮酚联合5-氟尿嘧啶对人肝癌SMMC-7721细胞增殖的影响

目的:探讨丹皮酚(Paeonol)单用及联合5-氟尿嘧啶(5-FU)对人肝癌细胞系SMMC-7721的增殖抑制作用。方法:采用MTT法及光镜观察不同浓度Paeonol、5-FU单独和联合应用不同时间对SMMC-7721细胞增殖抑制作用,利用中效原理判定两药合用的效果。结果:两种药物单独应用时对SMMC-7721细胞的抑制作用呈明显的剂量依赖和时间依赖效应关系。两药合用大剂量时(大于中效浓度)为拮抗作用,小剂量(小于中效浓度)时为协同作用;两药给药时间及给药顺序影响效应大小。结论:Paeonol与5-FU均可抑制SMMC-7721细胞的增殖,两药合用大剂量时为拮抗效应,小剂量时为协同效应;给药时间及给药顺序可影响效应大小。     

根皮素对HepG2肝癌细胞增殖和凋亡影响的实验研究

目的：探讨根皮素对人肝癌HepG2细胞增殖和凋亡的影响。方法：MTT法检测不同浓度（30、40、50 ug/mL）根皮素对肝癌 HepG2 细胞增殖的抑制作用,流式细胞技术检测根皮素对HepG2细胞凋亡的影响,ELISA 法检测不同浓度根皮素干预后细胞中 Bcl-2 和Bax表达的变化,Western blot法检测30 ug/mL根皮素在8,16,24 小时后检测p-AKT 蛋白表达情况。结果：30、40 和50 ug/mL 的根皮素对肝癌HepG2 细胞的增殖均有抑制作用（P＜0.01）,同时,30、40 和50 ug/mL 的根皮素在24 小时后可诱导 HepG2 细胞发生早期凋亡,凋亡率分别为0.1321± 0.0224, 0.2607± 0.0457, 0.3712± 0.0884（P＜0.01）;另外,30、40 和50 ug/mL的 根皮素作用24 小时后细胞内Bcl-2 表达降低,Bax 表达增高（P＜0.01）;最后,30 ug/mL根皮素可以明显减少p-AKT 表达量,这 种作用呈现时间依赖性。结论：根皮素能够抑制肝癌HepG2 细胞的增殖和促进细胞凋亡。     

黄芩素对人口腔鳞癌细胞增殖和侵袭的作用及其机制

目的：研究黄芩素（BAI）抑制口腔鳞癌细胞（TCA8113）增殖与侵袭及与ERK-FAK的可能关系。方法：本研究分为两次实验,每次实验有4个组：control,20 μmol/L BAI,40 μmol/L BAI,80 μmol/L BAI;control,40 μmol/L BAI,MEK抑制剂（0.33 nmol/L）,MEK抑制剂（0.33 nmol/L）+40 μmol/L BAI。每组3个复孔,各组分别处理24 h和48 h。利用CCK8实验检测黄芩素对口腔鳞癌细胞的增殖抑制作用;半定量PCR及Western blot分析黄芩素对E-cadherin和Vimentin的影响;利用Western blot分析黄芩素对ERK,p-ERK,FAK以及p-FAK的调节作用;采用MEK抑制剂（U0126）,利用Western blot分析其对黄芩素的调控作用。结果：黄芩苷处理组的细胞增殖率明显低于对照组（P<0.01）;黄芩素处理组对E-cadherin的mRNA和蛋白水平的上调作用明显高于对照组,对Vimentin的mRNA和蛋白水平的下调作用也明显低于对照组（P<0.01）;黄芩素处理组的p-ERK和p-FAK的蛋白水平明显低于对照组（P<0.01）,但总的ERK与FAK的蛋白水平与对照组相比没有明显的差别（P<0.05）;MEK抑制剂处理组的E-cadherin的蛋白水平明显高于对照组（P<0.01）,Vimentin,p-ERK和p-FAK的蛋白水平明显低于对照组（P<0.01）,但总的ERK与FAK的蛋白水平与对照组相比没有明显的差别（P<0.05）。结论：黄芩素能够抑制口腔鳞癌细胞的增殖以及侵袭,其机制可能与黄芩素抑制ERK-FAK信号通路有关。     

FUT4-siRNA增强5-aza-dC对鳞癌细胞增殖和迁移的抑制

岩藻糖基转移酶IV（fucosyltransferase IV,FUT4）是催化蛋白质岩藻糖基化的关键酶．已经证明,FUT4-siRNA能够抑制鳞癌细胞的增殖．5-氮杂-2-脱氧胞苷（5-aza-dC）是临床常用化疗药物,但5-aza-dC是否对鳞癌有治疗作用,以及与FUT4-siRNA联合使用能否加强对鳞癌细胞增殖和迁移的抑制尚不清楚．本研究以鳞癌细胞系A431和SCC12为对象,探讨5-aza-dC及其与FUT4-siRNA联合使用对细胞增殖和迁移的影响．MTT结合流式细胞周期分析显示,5-aza-dC处理A431和SCC12细胞4 d后,细胞增殖被明显抑制,抑制率分别为18%和20% (P<0.05);与对照组比较,加药处理组G1期细胞数量减少,S期细胞数量明显增加．Western印迹结果揭示,A431细胞FUT4表达水平较SCC12细胞高．经5-aza-dC处理后SCC12细胞FUT4表达有所增加,但仍低于A431细胞中的表达．FUT4-siRNA转染结合台盼蓝活细胞记数证明,FUT4-siRNA明显降低细胞FUT4表达,5-aza-dC处理同时转染FUT4-siRNA的A431和SCC12细胞增殖进一步被抑制,抑制率分别为54%和60% (P<0.05)．细胞划痕法显示,5-aza-dC与FUT4-siRNA联合使用,对细胞迁移能力的抑制作用比5-aza-dC单独使用增强．上述结果提示,5-aza-dC通过诱导细胞S期阻滞抑制鳞癌细胞增殖,FUT4-siRNA与5-aza+dC联合使用可加强对细胞增殖和迁移的抑制．     

低分子量核桃仁蛋白酶水解物抑制MCF-7细胞增殖

摘要：用木瓜蛋白酶制备核桃仁蛋白酶水解物,通过细胞增殖分析试验,研究其对人乳腺癌细胞（MCF-7）增殖的影响,结果显示：水解物具有明显的抑制细胞生长作用,IC50值为1.62mg/mL。用超滤方法将核桃仁蛋白酶水解物,分为10～5kDa、5～3kDa和＜3kDa3个组分,研究不同分子量范围的组分对MCF-7细胞增殖影响的结果表明,MW＜3kDa的低分子量组分具有较强的增殖抑制作用。对3个不同组分进行氨基酸含量分析,结果表明：具有较强抑制癌细胞生长作用的低分子量组分中,疏水性氨基酸及中性极性氨基酸含量较高,酸性极性氨基酸含量少于其他组分。     

CRKL promotes cell proliferation in gastric cancer and is negatively regulated by miR-126

V-crk avian sarcoma virus CT10 oncogene homolog-like (CRKL) is a member of CRK family and act as an adaptor protein participating in intra-cellular signal transduction. The role of CRKL in gastric cancer (GC) remains unclear. In this study, we show that CRKL was aberrantly highly expressed in both GC tumor specimens and cell lines (SGC-7901, MKN-45, MKN-28 and SUN-16). The expression of CRKL was significantly correlated with GC clinicopathologic features including tumor size, local invasion, lymph node metastasis and TNM stages. Knock-down of CRKL in SGC-7901 cells induced a suppression of cell proliferation along with a significant arrest of cell cycle in G0/G1 phase, however, no significant influence was observed on cell apoptosis. We validate that miR-126, a suppressor in GC, was a negative regulator of CRKL by directly combining with the 3′ untranslated region of CRKL mRNA, and over-expression of miR-126 inhibited the protein expression of CRKL significantly. These results suggest that CRKL may function as an oncogene in GC by promoting the GC cell proliferation, which provides us a likely biomarker and a potential target for GC prevention, diagnosis and therapeutic treatment. Moreover, the targeting relationship between CRKL and miR-126 partly reveals the mechanism of miR-126 on GC suppression.     

脂联素对人胃癌细胞HGC27生长和迁移能力的影响

目的 探讨脂联素对胃癌细胞HGC27的生长和迁移能力的影响.方法 应用Western blot方法检测脂联素受体adipoR1和adipoR2在HGC27细胞中的表达.以不同浓度脂联素干预细胞,MTT法检测细胞生长情况,应用细胞划痕试验检测脂联素干预对细胞迁移能力的影响.结果 两种脂联素受体在HGC27细胞中均有表达,随着脂联素浓度的升高和培养时间的延长HGC27细胞的生长受到抑制,脂联素可以抑制细胞的迁移能力.结论 脂联素可抑制HGC27细胞生长和迁移能力,其机制可能是通过与受体结合完成的.     

长链非编码RNA Hotair通过调控巨噬细胞表型转换促进胃癌细胞增殖与侵袭

目的探讨胃癌细胞是否通过长链非编码RNA Hotair作用于巨噬细胞,将其转化为癌症支持细胞,进而促进胃癌的增殖与侵袭。 方法实验分为对照组与AGS细胞共培养组,转染实验分为对照组、Hotair过表达组和RNA干扰组胃癌细胞与巨噬细胞共培养实验检测巨噬细胞表型转换。进行原位杂交实验对M2型巨噬细胞与lncRNA Hotair共定位。通过RT-?PCR实验检测并筛选出促进巨噬细胞表型转换的关键lncRNA。通过RNA干扰技术敲低胃癌细胞lncRNA水平并进行共培养实验。随后通过CCK-8实验与Transwell实验检测转型后的癌症相关巨噬细胞对胃癌细胞增殖与侵袭能力的影响。两组间均数比较采用t检验,多组均数间比较采用单因素方差分析,组间多重比较采用SNK-q检验。 结果共培养实验结果表明,相比于对照组（5.63±1.97）个,AGS细胞组中含有更多的CD206阳性M2型癌症相关巨噬细胞（32.51±5.44）个,两者比较差异有统计学意义（t =25.742,P = 0.001）;ELISA实验也证明AGS细胞组的巨噬细胞分泌更多的抑炎因子[TGF-β：（163.45±54.91）pg/ml,对照组：（87.32±19.24）?pg/ml;IL-4：（156.83±69.25）pg/ml,对照组：（49.94±17.55）pg/ml;IL-10：（385.65±24.75）pg/ml,对照组：（98.82±46.26）pg/ml],两组间比较差异有统计学意义（t?= 7.167,8.203,29.991,P均< 0.05）。GEO数据库鉴定并使用RT-PCR筛选出Hotair为关键lncRNA,随后的RNA干扰实验表明,Hotair敲低会抑制巨噬细胞的转变（CD206阳性细胞数量由41.12±6.91变为21.45±2.19）,进而降低胃癌细胞的增殖与侵袭能力。 结论胃癌细胞的lncRNA Hotair会被巨噬细胞摄取,将其转化为癌症相关巨噬细胞,进而促进胃癌细胞的增殖与侵袭能力,这为胃癌的治疗提供了新的可能的靶点。     

Upregulation of MicroRNA-107 induces proliferation in human gastric cancer cells by targeting the transcription factor FOXO1

MicroRNA-107 (miR-107) has been demonstrated to regulate proliferation and apoptosis in many types of cancers. Nevertheless, its biological function in gastric cancer remains largely unexplored. Here, we found that the expression level of miR-107 was increased in gastric cancer in comparison with the adjacent normal tissues. The enforced expression of miR-107 was able to promote cell proliferation in NCI-N87 and AGS cells, while miR-107 antisense oligonucleotides (antisense miR-107) blocked cell proliferation. At the molecular level, our results further revealed that expression of FOXO1 was negatively regulated by miR-107. Therefore, the data reported here demonstrate that miR-107 is an important regulator in gastric cancer, which will contribute to a better understanding of the important mis-regulated miRNAs in gastric cancer.     

Atractylenolide I-mediated Notch pathway inhibition attenuates gastric cancer stem cell traits

Atractylenolide I (AT-I), one of the main naturally occurring compounds of Rhizoma Atractylodis Macrocephalae, has remarkable anti-cancer effects on various cancers. However, its effects on the treatment of gastric cancer remain unclear. Via multiple cellular and molecular approaches, we demonstrated that AT-I could potently inhibit cancer cell proliferation and induce apoptosis through inactivating Notch pathway. AT-I treatment led to the reduction of expressions of Notch1, Jagged1, and its downstream Hes1/ Hey1. Our results showed that AT-I inhibited the self-renewal capacity of gastric stem-like cells (GCSLCs) by suppression of their sphere formation capacity and cell viability. AT-I attenuated gastric cancer stem cell (GCSC) traits partly through inactivating Notch1, leading to reducing the expressions of its downstream target Hes1, Hey1 and CD44 in vitro. Collectively, our results suggest that AT-I might develop as a potential therapeutic drug for the treatment of gastric cancer.     

Connexin32 inhibits gastric carcinogenesis through cell cycle arrest and altered expression of p21Cip1 and p27Kip1

Gap junctions and their structural proteins, connexins (Cxs), have been implicated in carcinogenesis. To explore the involvement of Cx32 in gastric carcinogenesis, immunochemical analysis of Cx32 and proliferation marker Ki67 using tissue-microarrayed human gastric cancer and normal tissues was performed. In addition, after Cx32 overexpression in the human gastric cancer cell line AGS, cell proliferation, cell cycle analyses, and p21^Cip1 and p27^Kip1 expression levels were examined by bromodeoxyuridine assay, flow cytometry, real-time RT-PCR, and western blotting. Immunohistochemical study noted a strong inverse correlation between Cx32 and Ki67 expression pattern as well as their location. In vitro, overexpression of Cx32 in AGS cells inhibited cell proliferation significantly. G₁ arrest, up-regulation of cell cycle-regulatory proteins p21^Cip1 and p27^Kip1 was also found at both mRNA and protein levels. Taken together, Cx32 plays some roles in gastric cancer development by inhibiting gastric cancer cell proliferation through cell cycle arrest and cell cycle regulatory proteins. [BMB Reports 2013; 46(1): 25-30]     

Matrix metalloproteinase 11 depletion inhibits cell proliferation in gastric cancer cells

Our previous study has shown that matrix metalloproteinase 11 (MMP11) is highly expressed in tumor cell lines and primary tumor of gastric cancer (GC). In order to reveal the correlation between expression of MMP11 and biological features of GC cell, we have constructed the recombinant plasmids producing hairpin small interfering RNA (siRNA) to target MMP11 mRNA using a vector-based RNA interference technology. Stable transfection of recombinants into GC cell line BGC823 specifically depleted the mRNA and protein of MMP11 as demonstrated by RT-PCR and Western blotting analysis. The siRNA-treated cells exhibited significantly decreased growth ability compared with mock transfectants and parental BGC823 cells. Furthermore, colony formation of MMP11 deficient cells was dramatically inhibited in soft agar and tumorigenicity was reduced in nude mice, respectively. These results provide new insights into the function of MMP11 and suggest that MMP11 may play an important role in the control of cell proliferation and tumor development in GC.     

Effects of thyroid hormones on human breast cancer cell proliferation

The involvement of estrogens in breast cancer development and growth has been well established. However, the effects of thyroid hormones and their combined effects with estrogens are not well studied. We investigated the response of human breast cancer cells to thyroid hormone, particularly the role of T3 in mediating cell proliferation and gene expression. We demonstrated that 17β-estradiol (E2) or triiodothyronine (T3) promoted cell proliferation in a dose-dependent manner in both MCF-7 and T47-D cell lines. The E2- or T3-dependent cell proliferation was suppressed by co-administration of the ER antagonist ICI. We also demonstrated that T3 could enhance the effect of E2 on cell proliferation in T47-D cells. Using an estrogen response element (ERE)-mediated luciferase assay, we determined that T3 was able to induce the activation of ERE-mediated gene expression in MCF-7 cells, although the effects were much weaker than that induced by E2. These results suggest that T3 can promote breast cancer cell proliferation and increase the effect of E2 on cell proliferation in some breast cancer cell lines and thus that T3 may play a role in breast cancer development and progression.