Estrogen Receptor Levels and Tumor Growth in a Series of Pituitary Clonal Cell Lines in Rats

Four kinds of in vitro clonal pituitary tumor cell lines named MtT/Se, MtT/SM, MtT/S and MtT/ E, each of which shows different sensitivity to estrogen on proliferation, were inoculated into fat pad of ovariectomized rats and estrogen-loaded ovariectomized rats at 10⁵ and 10⁶ cells/site. They formed tumor with average latency ranging from 30 to 71 in ovariectomized rats and 13 to 63 days in estrogenized rats inoculated with 106 cells. MtT/Se was highly sensitive to estrogen for growth, and MtT/SM also grew well in estrogenized rats. With MtT/S and MtT/E, there was no significant shortening of average tumor latency in estrogenized rats. In vivo , the cytosolic estrogen receptor (ER) levels of MtT/Se, SM, S and E were measured to be 452 ±66, 370 ±115, 260 ±16 and 83 ±8 fmol/ mg protein, respectively. In vitro , however, the lowest ER level was noted in MtT/Se. Histologically, all four tumors grown in rats were composed of homogeneous round cells, and MtT/Se contained particularly large nucleated cells. In MtT/E, the cells appeared to be changing into ftbromatous cells. Three cell lines except MtT/E maintained the function of hormonal secretion in vivo as well as in vitro . Serum GH level was increased in rats with MtT/Se and MtT/S. Increased levels of both prolactin and growth hormone were measured in sera of rats with MtT/SM. Increases of hormones as well as tumor sizes were promoted by the estrogen.     

Selenium Causes Growth Inhibition and Apoptosis in Human Brain Tumor Cell Lines

We examined the effect of the trace element selenium on human glioma cell lines: T98G, U373MG, and U87MG, in addition to dermal fibroblast cells. Cultures were incubated with sodium selenite, and the following parameters were studied: cell growth, mitochondrial function, and ultrastructure. Cell growth was assayed by counting the number of viable cells after treatment with selenium. Mitochondrial function was analyzed using the MTT (tetrazolium salt reduction) assay. Apoptosis was determined by evaluating nuclear chromatin condensation by electron microscopy.The results indicated that selenium had a significant inhibitory effect on the growth of the tumor cells but had little effect upon dermal fibroblasts which had been passaged numerous times. Selenium also induced mitochondrial damage as shown by MTT assay in two brain tumor cell lines and in minimally passaged fibroblasts, but it had little effect upon the high-passage fibroblasts. Ultrastructurally, mitochondria had electron-dense inclusions resulting from selenium treatment. High rates of apoptosis were induced by selenium in the tumor cell lines and in the minimally passaged fibroblasts, whereas the fibroblasts with a high number of passages had some resistance to selenium treatment. This study correlates the adverse effects of selenium on mitochondrial function, inhibition of cell growth, and apoptosis and shows that selenium similarly affects three different brain tumor cell lines and minimally passaged fibroblasts. Further, the results with fibroblasts show that some types of cells after repeated passages can develop resistance to selenium damage.     

丁酸钠对人子宫内膜癌细胞系HHUA细胞增殖影响的研究

目的 :探讨丁酸钠 (NaB)对人子宫内膜癌细胞系HHUA细胞体外增殖的影响及机制。方法 :不同浓度的NaB作用于体外培养的人子宫内膜癌细胞系HHUA ,通过绘制细胞生长曲线观察NaB对细胞生长的抑制作用 ;用流式细胞仪定量分析细胞周期分布 ;用WesternBlot分析p2 1、p5 3、pRb和E2F1蛋白表达。结果 :NaB能诱导HHUA细胞周期G1期阻滞 ,上调p2 1蛋白表达 ,促进pRb去磷酸化 ,下调E2F1和p5 3蛋白表达。结论 :NaB能抑制HHUA细胞体外生长 ,其诱导细胞周期G1期阻滞可能与p2 1等细胞周期调节蛋白的表达改变有关。     

全反式维甲酸对卵巢癌细胞系黏附分子表达的影响

目的:探讨ATRA作用于两种细胞系(3AO,ES2)后两种粘附分子E-cad、CD44在mRNA水平和蛋白水平上的变化.方法:用RT-PCR检测3AO,ES2两种细胞系经ATRA作用后E-cad,CD44在mRNA水平的变化,应用Western blot检测3AO,Es2两种细胞系经ATRA作用后E-cad,CD44在蛋白水平上的变化.结果:两种细胞系经ATRA处理后,E-cad在mRNA水平及蛋白水平上表达均增加,统计学差异有显著性P<0.05;CD44在mRNA水平上表达减少,统计学显示差异有显著性,P<0.05;在蛋白水平上的表达有下降趋势,但未显示出明显的统计学差异,P>0.05.结论:ATRA可能通过改变癌细胞表面的粘附分子来抑制卵巢癌细胞的侵袭和远处转移.     

Effect of Human Epidermal Growth Factor on Cell Growth and Its Receptor in Human Gastric Carcinoma Cell Lines

The effect of human epidermal growth factor (hEGF) on the growthof various histological types of six human gastric carcinomacell lines was examined. The cell lines had relatively highaffinity EGF receptors (dissociation constant Kd = 10^–9to 10^–10 M). One gastric cancer cell line, MKN-74 (welldifferentiated adenocarcinoma) showed no response to hEGF, incell growth, DNA synthesis or ¹²⁵I-hEGF cell binding. Therewere no apparent correlations between histological type andcell growth, DNA synthesis or number of EGF receptors in thesecells. The number of EGF receptors and the Kd value of the gastriccarcinoma cell lines varied with their internal and externalenvironments. hEGF concentrations corresponding to maximum stimulationin DNA synthesis varied between cell lines. The results suggestsome gastric carcinoma cells to have EGF receptors and theirgrowth seemingly to be stimulated by EGF in vitro. There are,however, no obvious correlations between the effect of hEGFon the growth of human gastric carcinoma cell lines or theirhistological type.     

p53 Antisense Oligonucleotide Inhibits Growth of Human Colon Tumor and Normal Cell Lines

We examined the relationship between the expression of mutant p53 proteins and tumor cell growth using a p53 antisense oligonucleotide (5'-CCCTGCTCCCCCCTGGCTCC-3'). The oligonucleotide inhibited the growth of three human colon tumor cell lines (DLD-1, SW620 and WiDr), which produce only mutant p53 proteins with different mutation sites. Treatment of DLD-1 cells with the p53 antisense oligonucleotide caused a decrease in the level of p53 mutant protein. Synthesis of DNA in DLD-1 and SW620 cells was inhibited more potently than that of RNA or protein after antisense treatment. Furthermore, these cells were accumulated in the S phase when DNA synthesis was inhibited. Meanwhile, the antisense oligonucleotide also inhibited the growth of three human normal cell lines (WI-38, TIG-1 and Intestine 407). While treatment of WI-38 and TIG-1 cells with the antisense oligonucleotide inhibited synthesis of DNA more potently than that of RNA or protein, these normal cells were accumulated in the G0/G1 phase. These results suggest that p53 proteins, either with or without mutation, play a pivotal role in the growth of tumor and normal cells, but that mutant and wild-type p53 proteins may function differently in cell growth.     

全反式维甲酸联合顺铂在诱导人头颈癌 TCA8113细胞凋亡中的作用

目的：研究全反式维甲酸（ATRA）与顺铂对人头颈癌 TCA8113细胞凋亡的影响。方法 ATRA 和顺铂单独及联合作用于 TCA8113细胞,采用 MTT 法检测细胞生长,并观察细胞形态变化;使用流式细胞仪检测细胞周期及凋亡;通过 western blot 实验检测 caspase-3表达情况。结果 ATRA 作用于 TCA8113细胞后,细胞生长明显受到抑制,细胞形态发生改变,细胞凋亡比例明显增加,caspase-3蛋白表达下调,ATRA 与顺铂联合作用于肿瘤细胞后,其抑癌作用加强。结论 ATRA 联合顺铂对人头颈癌 TCA8113细胞具有协同抑癌作用。     

Procoagulant Activity of Human Neuroblastoma Cell Lines, in Relation to Cell Growth, Differentiation and Cytogenetic Abnormalities

Procoagulant activity (PCA) was investigated in relation to cell growth, differentiation, and cytogenetics in seven human neuroblastoma cell lines. Before 5-bromodeoxyuridine (BrdUrd) treatment, PCA was notably heterogeneous, with the highest activity in NCG (S-type in morphology) 40-to 100-fold greater than the lowest activity in SK-N-D2 (N-type). PCA was not related to 1p abnormalities. After BrdUrd treatment at 5 μg/ml for 6 days, PCA increased 6.8-fold in GOTO and 2.7-fold in SK-N-DZ with associated growth inhibition and morphological changes (I-type morphology converted to S-type in GOTO and N-type converted to an advanced N-type in SK-N-DZ). In contrast, only growth suppression was observed in 2 other cell lines, and no changes in PCA, growth or morphology were induced in the remaining 3 cell lines.     

土槿乙酸增强9顺式维甲酸对白血病细胞生长的抑制作用

目的观察过氧化物酶体激活物活化受体γ (PPARγ)的配体土槿乙酸(PLAB)联合维甲类X受体α (RXRα)的配体9-顺式维甲酸(9-cis RA)对白血病细胞生长的影响。方法应用MTT 法检测细胞生长抑制率,流式细胞术和Hoechst33342/PI染色分析HL-60细胞凋亡及细胞周期变化,RT-PCR检测PPARγ和RXRα mRNA表达。结果HL-60细胞系上有PPARγ和RXRα的表达,经配体联合作用后能明显抑制细胞生长,呈剂量依赖关系;细胞出现明显凋亡形态学改变和亚G₁峰;PPARγ和RXRα mRNA表达明显增强。结论PLAB能显著增强9-cis RA对HL-60细胞的生长抑制作用,其机制与凋亡诱导效应有关。     

维甲酸和甘草酸联合对人肺癌细胞增殖和侵袭抑制作用的研究

目的　探讨全反式维甲酸和甘草酸单独及联合作用对高转移人肺癌细胞 (PGCL3 )增殖和侵袭的抑制作用。方法　用维甲酸和甘草酸处理PGCL3细胞 ,通过细胞增殖抑制试验、软琼脂集落形成试验、侵袭、运动和黏附试验、以及组织蛋白酶B活性的测定 ,观察PGCL3细胞增殖和侵袭能力的变化。结果　维甲酸和甘草酸可减弱PGCL3细胞增殖能力 ,并呈剂量依赖性 ,半抑制浓度IC50 分别为 12 .6μmol/L和 1.8mmol/L。 2 .5 μmol/L和 5 .0 μmol/L维甲酸、0 .5mmol/L和 1.0mmol/L甘草酸能抑制PGCL3细胞的侵袭能力 (P <0 .0 5和P <0 .0 1) ,且有剂量依赖性。 5 .0 μmol/L维甲酸和 0 .5mmol/L甘草酸联合作用对PGCL3细胞的侵袭抑制率高于两药单独作用之和 ,呈协同作用。上述浓度甘草酸对细胞的运动、黏附、组织蛋白酶B分泌和软琼脂集落形成率均有显著抑制作用 (P <0 .0 1)。结论　维甲酸和甘草酸对PGCL3细胞的增殖和侵袭有抑制作用 ,两药有协同作用 ,甘草酸抗侵袭机理不是对侵袭的某一环节的阻断 ,而是对侵袭各个基本环节都有抑制作用     

不同剂量贝伐单抗联合伊立替康对荷人结肠癌DLD-1裸鼠皮下移植瘤生长的影响

[目的]观察不同剂量贝伐单抗与伊立替康联合对人结肠癌裸鼠皮下移植瘤生长及肿瘤血管生成的影响。[方法]接种人结肠癌DLD-1细胞的裸鼠21只,随机分为4组:无菌生理盐水对照组(A组),5mg/kg贝伐单抗联合伊立替康化疗组(B组),10mg/kg贝伐单抗联合伊立替康化疗组(C组)和单纯伊立替康化疗组(D组)(A、B、C组每组各5只,D组6只,各组伊立替康剂量均为66.7mg/kg)。于d1,5,9(q4d×3)分别给药,治疗第10d处死裸鼠,观察肿瘤生长情况,计算抑瘤率,免疫组化法检测肿瘤组织微血管密度(MVD),评价肿瘤坏死情况。[结果]A、B、C、D组肿瘤体积分别为:646.24±397.33mm3、240.11±147.44mm3、346.21±298.59mm3、399.11±254.09mm3。B、C两组比较,肿瘤体积差异未达统计学意义(P=0.208)。与A组比较,B、C、D组抑瘤率分别为62.85%、47.91%、39.59%。A、B、C、D各组微血管密度(microvesseldensity,MVD)分别为7.000±0.71、4.940±0.58、5.080±1.25、5.557±2.04,经Dunnett检验,与A组比,B、C组肿瘤MVD均有显著性差异(P值分别为0.028、0.039),而D组与A组,及B组与C组在MVD表达上差异未达到统计学意义(P值分别为0.086、0.083)。移植瘤组织HE染色后发现各组肿瘤组织内均有不同程度的坏死。其中,对照组多以轻中度坏死为主,用药后坏死面积均增加,各组坏死分级经秩和检验,χ2=4.73,P=0.193。两两间比较,P值均大于0.05,各治疗组间的坏死差异并不明显。治疗组肿瘤细胞的凋亡较明显。[结论]不同剂量贝伐单抗联合伊立替康对荷DLD-1裸鼠移植瘤有抑制作用,联合用药有显著协同作用,推测其作用机制可能与抑制肿瘤微血管形成、诱导细胞凋亡和死亡增加有关。5mg/kg及10mg/kg贝伐单抗对移植瘤体积及MVD上的作用差异不显著。     

Increase in the Level of P-Glycoprotein mRNA Expression in Multidrug-resistant K562 Cell Lines Treated with Sodium Butyrate Is Not Accompanied with Erythroid Differentiation

We examined the effects of hemin, sodium butyrate and mitomycin C on levels of P-glycoprotein mRNA in human myelogenous K562 cells by northern blot analysis. After treatment with sodium butyrate a dose-dependent increase of P-glycoprotein mRNA expression was observed in the adriamycin-resistant K562 and vincristine-resistant K562 lines. With 10 m M sodium butyrate, the level of P-glycoprotein mRNA reached 20 times that of control adriamycin-resistant K562 and with 30 m M sodium butyrate, it exceeded 5 times that of control vincristine-resistant K562. In contrast, hemin and mitomycin C had almost no effect on P-glycoprotein mRNA. In this experiment, since expression of P-glycoprotein mRNA was not necessarily accompanied with induction of erythroid differentiation, the increased amount of P-glycoprotein mRNA is unlikely to be a result of differentiation.     

载体对癌胚抗原DNA疫苗在小鼠体内表达CEA及诱导体液免疫应答的影响

目的　比较用pcDNA3和pCI-neo做载体构建的癌胚抗原 (CEA)真核表达质粒在小鼠体内表达CEA及诱导体液免疫应答的差别。方法　将两套重组质粒分别肌注BABL/c小鼠 ,ELISA法检测二者在小鼠体内表达CEA及抗 -CEA水平。结果　以pCI -CEA免疫的小鼠体内表达CEA量高于pcDNA3-CEA组 ,二者OD值分别为 0 65和 0 35 ;抗体量的表达前者OD值为 0 89,后者为0 70 ,比较差异有显著性 (P <0 .0 5 )。结论　表达载体的结构对抗原的表达及抗体的产生具有重要作用     

单用TAM及联合应用5-FU对结肠癌细胞株生长抑制作用及增殖凋亡的影响

目的探讨他莫昔芬(tamoxifen,TAM)单独或联合5-FU化疗对结肠癌细胞株生长抑制作用及凋亡的影响.方法应用MTT法,比较单纯应用TAM和TAM与5-FU联合对SW480、HT29细胞株生长抑制作用,通过药物量-效关系曲线,观察TAM有无化疗增敏作用,同时检测PCNA和AI,探讨TAM联合5-FU对增殖、凋亡的影响.结果单独应用TAM对SW480、HT29细胞株无生长抑制作用;TAM联合5-FU在一定浓度时可抑制SW480和HT29细胞的生长,提高对5-FU的敏感性,起到化疗增敏作用.通过对PCNA和AI 2个指标的检测,随着浓度的增加和时间的延长,TAM联合5-FU抑制细胞的增殖和促进细胞的凋亡均呈上升趋势.结论一定浓度的TAM能增加人结肠癌细胞株SW480、HT29对化疗药物5-FU的敏感性,抑制细胞增殖,促进细胞凋亡.     

PS-ODN对结肠癌细胞生长及端粒酶活性影响的研究

目的：观察全硫化修饰的抗端粒酶反义寡核苷酸（PS-ODN）对结肠癌LS-174T细胞的抑制作用,探讨端粒酶抑制剂PS-ODN对结肠癌细胞的抑制作用机制.方法：采用反义技术在逆转录水平阻断端粒酶模板,从而诱导细胞凋亡,通过电镜、FCM、PCR-Elisa等方法评估抑制效果.结果：PS-ODN的最佳剂量为10 μmol/L;作用10天后,PS-ODN组LS-174T细胞集落形成率明显低于CPS-ODN组和对照组（P＜0.01）;PS-ODN组细胞有明显的形态学改变;作用72 h后PS-ODN组细胞出现凋亡峰,而对照组未出现;PS-ODN组细胞端粒酶活性明显低于CPS-ODN组和对照组相（P＜0.01）.结论：特定的核苷酸序列可抑制端粒酶活性,诱导细胞凋亡,为肿瘤的治疗提出新手段和新思路奠定了实验基础.     

Celecoxib对肺癌细胞生物学行为影响的研究

目的:探讨Celecoxib对高、低不同转移能力的肺腺癌细胞株(Anip973、AGZY83-a)增殖的抑制作用及对细胞周期、形态、粘附、浸润、趋化运动能力的影响.方法:用不同浓度的Celecoxib培养液终浓度为(5、10、20、40、80、160μmol/L)处理不同肺癌细胞株,采用四唑氮蓝试验(MTT Assay)法测定其对细胞增长的抑制情况,采用碘化丙啶(PI)染色,流式细胞(FCM)技术,观察Celecoxib作用不同肺癌细胞株后对细胞生长周期的影响,并应用Transwell小室观察对细胞运动、浸润能力及对粘附能力的影响.结果:Celecoxib在一定范围内(10、20、40、80、160μmol/L)可有效地抑制Anip973、AGZY83-a肺癌细胞生长,并存在时间和剂量依赖性(P＜0.01);Celecoxib在40μmol/L浓度时培养24h对细胞周期无明显影响(P＞0.01);对肺癌细胞粘附、浸润、趋化运动能力明显抑制(P＜0.01);Celecoxib作用不同肺癌细胞后形态学有明显的改变.结论:Celecoxib对不同转移能力的肺癌细胞系Anip973、AGZY83-a具有明显的抑制作用,存在时间依赖性和在一定范围内剂量依赖性,对肺癌细胞粘附、浸润、趋化运动能力有明显抑制作用.     

FTY720抑制裸鼠人肝癌细胞系MHCC-97H移植瘤生长的实验研究

目的 探讨不同浓度FTY720对裸鼠人肝癌MHCC-97H移植瘤的抑制作用。方法建立裸鼠肝脏的人肝癌细胞系MHCC-97H移植瘤模型,然后腹腔注射不同浓度的FTY720,治疗1个月后观察肿瘤的抑制效应,采用免疫组化法检测肿瘤细胞的增殖细胞水平。结果FTY720治疗组（5mg／kg和10mg／kg）能明显抑制肿瘤的生长,尤以10mg／kg更显著．FTY720治疗组的P13K—Akt信号通路被抑制,Caspase-3表达水平上调,提示FTY720明显促进肿瘤细胞凋亡。结论免疫抑制剂FTY720是1种有效抑制肝脏移植瘤的抗肿瘤分子,其可能与抑制P13K—Akt信号通路、上调Caspase-3表达水平,进而诱导细胞凋亡密切相关。     

Stimulatory Effects of Retinoic Acid on Tumor Growth and Serum Insulin-like Growth Factor-1 in Rats Bearing Estrogen-responsive Pituitary Tumor MtT/Se

MtT/Se is one of 4 cell lines derived from an estrogen-dependent pituitary tumor, MtT/F84. The main difference between these tumor types is that MtT/F84 secretes both growth hormone (GH) and prolactin (PRL) whereas MtT/Se secretes only GH. MtT/Se grew slowly in ovariectomized (ovex) rats, but tumor growth was much faster in estrogen-treated ovex rats. Effects of dietary retinoic acid (RA) on tumor growth, serum GH and insulin-like growth factor-1 (IGF-1) levels were examined in ovex rats. Latency of tumor growth was shortened, and tumor take and weight were promoted by all- trans RA both in the presence and absence of exogenous estrogen. Serum GH and IGF-1 levels became increased in tumor-hearing rats whereas PRL levels remained unchanged. Serum IGF-1 levels exhibited a good correlation with tumor weights ( r =0.84). Our results suggest a close relationship between increase of tumor weight and stimulation of serum IGF-1 level by RA in tumor-bearing rats.