Growth inhibitory effect of paradicsompaprika in cancer cell lines

We investigated whether components of paradicsompaprika have direct antitumor effects or inhibitory effects on cancer growth, using its water extract. We applied collagen gel droplet embedded culture drug sensitivity test (CD-DST) as a screening method, which was developed based on the characteristics of cell culture on collagen matrix. Colon adenocarcinoma cells, epithelial cells of lung cancer, and cervical cancer cells were used. Paradicsompaprika is classified as Capsiucum annume L. var. grossum of Solanaceae. It is the first of the Hungarian species that was planted in Japan. It is available as TOMA-P in Japan. TOMA-P contains abundant carotenoids including capsanthin and beta-carotene. Water extract of paradicsompaprika was added to each cell at each concentration, and the mixture was cultured for 24 h and 7 days. The inhibitory effects against lung cancer and cervical cancer were observed concentration- and time-dependently. The effect was more prominent against lung cancer. The growth of bowel cancer cells was observed after the 7-day exposure of paradicsompaprika at the concentrations below the highest concentration compared to the control. At the highest concentration, the growth inhibition was not different between the 24-h exposure and the 7-day exposure, which suggests that tumor dormancy was induced. Results of the present study suggest that the water extract of paradicsompaprika can be a candidate of a new anticancer agent. Fat soluble component of paradicsompaprika, capsanthin is regarded as an anti-promoter of cancer. Thus, paradicsompaprika possesses chemopreventive and inhibitory effects on cancer cells.     

Growth inhibitory effect of LH-RH analogs on human breast cancer cells

The antiproliferative effect of two LH-RH agonists (Pro 9-LH-RH ethylamide and D Ser(t BU)6 Aza Gly 10-LH-RH, ICI 118630) on the human breast cancer cell line CG5 is reported. Although ineffective when used alone, both analogs inhibited in a dose-dependent fashion the growth stimulatory effect of estradiol. LH-RH analogs did not influence the growth inhibitory effect of tamoxifen and medroxyprogesterone acetate. Likewise, these compounds neither modified basal estrogen and progesterone receptor levels nor prevented estrogen-induced increase of progesterone receptor. A marked antiproliferative effect of the analogs was also seen in cells stimulated with other mitogens, such as insulin and epidermal growth factor.     

青蒿琥酯抗人食管癌作用与调控CDC25A、TGFβ有关

目的:观察青蒿琥酯(Art)对人食管癌Eca109细胞株及裸鼠移植瘤的抑瘤作用,探讨Art诱导肿瘤细胞周期阻滞与CDC25A、TGFβ表达的关系。方法:利用MTT法测定不同浓度Art对Eca109细胞及正常人外周血单个核细胞(hPBMC)增殖的影响;流式细胞术(FCM)测定肿瘤细胞的细胞周期变化;观察Art对裸鼠人食管癌移植瘤的抑制情况;RT-PCR方法检测CDC25A mRNA表达情况,Western blot方法检测CDC25A和TGFβ蛋白表达情况。结果:Art能显著抑制Eca109细胞的增殖,IC50为(68.80±0.76)μmol/L,而对hPBMC的增殖则没有明显抑制作用。低浓度Art可将细胞阻滞于G0/G1期,S期细胞显著减少,当浓度达到100μmol/L时,Art可将细胞阻滞于G2/M期。Art各用药组肿瘤的体积及质量均明显小于模型组,体积抑瘤率最高可达76.4%,质量抑瘤率可达63.2%。Art可显著抑制Eca109细胞CDC25A mRNA及蛋白表达,同时显著上调TGFβ的蛋白表达水平。结论:Art可抑制肿瘤细胞生长,其机制可能为通过上调TGFβ的表达来抑制CDC25A的表达,进而调控细胞周期。     

Growth inhibitory effect of diheptyl diselenide on various human cancer cell lines

We tested the antiproliferative effects of Diheptyl Diselenide (DHDSe) on several different human cancer cell lines. Cells derived from human cancer (CG5), colon cancer (WIDR), laryngeal cancer (Hep-2), ovarian cancer (OV 166, OV 1225) and IM-9 lymphoblastoid cells were used. In all cell lines DHDSe inhibited cell growth in a dose dependent manner. At the highest concentration tested, an inhibition of cell proliferation ranging from 48% to 75% compared with control cells was observed. Our results show that DHDSe exerts a direct antiproliferative effect on human cancer cells in vitro and suggest that it may represent the parent compound of a new group of anticancer agents.     

Growth inhibitory effect of D-allose on human ovarian carcinoma cells in vitro

BACKGROUND: D-allose is a rare sugar found in nature and, because of its very limited amount and of the high cost associated with its synthesis, its physiological functions remain virtually unknown. The aim of the current study was to investigate the effect of D-allose on the proliferation of human ovarian carcinoma cells in vitro. MATERIALS AND METHODS: Human ovarian carcinoma cells (OVCAR-3 cell line) were exposed to rare sugars including D-allose, D-altrose, D-psicose and D-talitol. Cell growth was evaluated by MTT assay. Cell cycle analysis was carried out by flow cytometric assay. The expression of cell cycle regulatory proteins was determined by Western blot analysis. TUNEL assay was employed for the detection of apoptotic cells. RESULTS: D-allose had a significant inhibitory effect on ovarian cancer cell proliferation in a dose-dependent manner, and caused a moderate G2/M arrest in the cell cycle, up-regulation of Cdk inhibitors p21 and p27 levels, and the induction of apoptosis in OVCAR-3 cells. CONCLUSION: Our results show, for the first time, that D-allose inhibits the growth of ovarian carcinoma cells in vitro. Although the exact mechanisms remain unclear, these findings suggest that D-allose possesses a novel inhibitory property on ovarian carcinoma cell proliferation, and may represent a new class of compounds with possible therapeutic potential.     

葫芦素E对非小细胞肺癌细胞的生长抑制作用

目的:体外观察葫芦素E（cucurbitacin E,CuE）对非小细胞肺癌细胞系A549增殖的影响及分子作用机制。方法:采用MTT法检测不同浓度 CuE（0、1、10、100以及1000nmol/L）处理A549细胞24、48和72小时后的细胞增殖情况。流式细胞仪检测CuE对A549细胞凋亡的影响。 Western blot法检测被处理细胞中p-STAT3、p-Raf-1、p-MEK1/2、p-ERK1/2、Bcl-2、Fas蛋白表达水平的变化。结果:CuE可显著抑制A549细胞的增殖（P＜0.05）,且呈时间和浓度依赖性。流式细胞仪检测显示随着CuE作用浓度的逐渐升高（0、100、200、400nmol/L）,A549细胞凋亡率由（4.63±0.70）%分别提高到（6.80±0.10）%、（20.53±0.49）%、（24.57±0.55）%,差异有统计学意义（P均<0.05）。Western blot结果显示CuE处理A549细胞,可降低p-STAT3、p-Raf-1、p-MEK1/2、p-ERK1/2、Bcl-2蛋白表达水平,增强Fas蛋白表达水平,且上述作用随CuE浓度升高而增强。结论:CuE可显著抑制A549细胞的增殖并诱导凋亡,其作用机制与阻断STAT3和Raf/MEK/ERK信号通路,同时激活Fas信号通路有关。     

EGF对体外培养食管癌细胞增殖及迁徙能力的影响

目的:观察不同浓度表皮生长因子(epi-dermalgrowthfactor,EGF)对食管癌细胞株EC109和EC-1增殖及浸润能力等生物学特性的影响。方法:观察细胞形态,MTT检测细胞增殖活性,单克隆扩散实验和划痕损伤实验检测细胞的浸润迁徙能力,免疫荧光观察细胞骨架的组分微丝的改变。结果:高浓度组2株食管癌细胞形态发生上皮细胞-间叶样变(epithelial-mesenchy-maltransition,EMT);0·01~0·1μg/LEGF对EC109和EC-1食管癌细胞株均有轻微的抑制增殖效应,1~100μg/LEGF能明显抑制EC109和EC-1细胞的增殖,其中EGF的最大抑制效应浓度为10μg/L;单克隆扩散实验和划痕损伤实验表明,高浓度组均有细胞迁出;免疫荧光提示,高浓度EGF能诱导β-actin重新分布,细胞的长极出现较长的应力纤维束。结论:高浓度EGF对食管癌细胞株EC109和EC-1的增殖有一定的抑制作用,并且能促进食管癌细胞发生迁徙,诱导微丝发生明显重组。     

单链抗体阿霉素结合物对人肺腺癌细胞体外生长的抑制作用

目的观察抗肺腺癌单链抗体(ScFv)2A7-1-阿霉素(ADM)结合物对人肺腺癌细胞体外生长的抑制作用。方法从抗肺癌可溶性ScFv抗体分泌克隆2A7-1E清提取可溶性抗体,浓缩、亲和层析纯化,以分光光度计测定浓度。戊二醛法连接2A7-1、ADM制备结合物,分光光度计测定结合物中所含2A7-1和ADM的浓度,计算结合比例。集落形成试验观察该结合物对肺癌细胞体外生长的抑制作用。结果制备的2A7-1-ADM结合物中,ADM和2A7-1的克分子比为3：1。连接后的2A7-1-ADM免疫结合物仍可特异结合肺腺癌A2细胞,其对肺癌细胞的抑制作用是单纯使用ADM的4倍。结论2A7-1-ADM免疫结合物对肺癌细胞的生长抑制作用明显强于单独使用ADM,具有潜在的临床应用价值。     

Growth inhibitory effect of triple anti-tumor gene transfer using Semliki Forest virus vector in glioblastoma cells

The gene delivery of multiple tumor suppressors can provide an efficient tumor therapy in the case of malignant human glioblastomas containing multiple genetic alteration and inactivation. As such, the current study presents a new delivery system that can simultaneously express three anti-tumor genes using a Semliki Forest virus (SFV) vector in the expectation of combined or synergistic effects of angiogenesis inhibition by angiostatin and apoptosis induction by p53, PTEN and the rSFV particle itself. Recombinant SFV (rSFV) containing three anti-tumor genes (rSFV-Agt/p53/PTEN) were found to efficiently transduce and express each anti-tumor gene in glioblastoma cells. In addition, rSFV-Agt/p53/PTEN also resulted in a more effective induction of apoptosis in vitro and inhibition of tumor growth in nude mice when compared with other rSFVs containing only one or two anti-tumor genes. Accordingly, the current results demonstrate that a triple anti-tumor gene transfer using an rSFV vector would be a powerful strategy for regional cancer gene therapy.     

TGF beta inhibits Go/S-phase transition in primary fibroblasts. Loss of response to the antigrowth effect of TGF beta is observed after immortalization

Transforming growth factor beta (TGF beta) may act as a negative growth regulator in secondary cultures of rodent fibroblasts by preventing quiescent cells from re-entering the cell cycle. Although TGF beta inhibits the serum induced transition from the Go to the S phase it does not inhibit induction of fos, myc, and JE. Actively growing cells are also inhibited in their proliferation by picomolar amounts of TGF beta. In contrast several established cell lines are not inhibited by TGF beta and in these it can cause quiescent cells to resume proliferation. This resistance to TGF beta can be traced back to the early divisions of immortal cells emerging from a senescence crisis, suggesting that alterations in the response of normal fibroblasts to TGF beta are concurrent with an unlimited proliferative potential. Induction of DNA synthesis by TGF beta is preceded in 5 established cell lines by induction of PDGF B chain mRNA as well as of other mRNAs associated with cell replication such as fos, myc, and JE. None of these genes is induced by TGF beta alone in presenescent cells. These results indicate that TGF beta can negatively regulate growth of normal presenescent fibroblasts. Alterations in the responsiveness to TGF beta can be detected immediately after immortalization which may contribute to the increased proliferative potential of these cells.     

Growth inhibitory effect of green tea extract in Ehrlich ascites tumor cells involves cytochrome c release and caspase activation

We reported previously that the mechanism by which Green tea extract (GTE) elicited growth-inhibitory effects in Ehrlich ascites tumor cells involved a decrease in ornithine decarboxylase (ODC) activity and in cell viability. Decrease in ODC activity has been associated with apoptotic cell death and we therefore studied changes in cytochrome c release and caspase activation, which characterize apoptosis. GTE caused a dose- and time-dependent increase in caspase-3-like protease activation, preceded by a release of cytochrome c from the mitochondria. Inhibiting the activation of caspase-3 with acetyl-Asp-Glu-Val-Asp-alpha-aldehyde (caspase inhibitor) caused a reversal in the effect on cell viability.     

Expression of transforming growth factor beta (TGF beta) receptors and expression of TGF beta 1, TGF beta 2 and TGF beta 3 in human small cell lung cancer cell lines.

A panel of 21 small cell lung cancer cell (SCLC) lines were examined for the presence of Transforming growth factor beta receptors (TGF beta-r) and the expression of TGF beta mRNAs. By the radioreceptor assay we found high affinity receptors to be expressed in six cell lines. scatchard analysis of the binding data demonstrated that the cells bound between 4.5 and 27.5 fmol mg-1 protein with a KD ranging from 16 to 40 pM. TGF beta 1 binding to the receptors was confirmed by cross-linking TGF beta 1 to the TGF beta-r. Three classes of TGF beta-r were demonstrated, type I and type II receptors with M(r) = 65,000 and 90,000 and the betaglycan (type III) with M(r) = 280,000. Northern blotting showed expression of TGF beta 1 mRNA in ten, TGF beta 2 mRNA in two and TGF beta 3 mRNA in seven cell lines. Our results provide, for the first time, evidence that a large proportion of a broad panel of SCLC cell lines express TGF beta-receptors and also produce TGF beta mRNAs.     

TGF alpha in normal physiology

This paper reviews our work on the localization of transforming growth factor-alpha (TGF alpha) in normal adult tissues and the regulation of its synthesis and that of its receptor. We detected TGF alpha immunohistochemically in brain neurons and showed the TGF alpha mRNA derived from the human brain stem is virtually identical to the mRNA derived from human renal tumour cells. In cells derived from anterior pituitary glands, another site of TGF alpha expression, TGF alpha secretion and mRNA levels can be regulated by phorbol esters. The expression of the epidermal growth factor (EGF) receptor, which is also the TGF alpha receptor, is also stimulated by phorbol esters. Similar stimulation of receptor and ligand expression in human breast cancer cells was shown in response to phorbol esters and EGF. The ability of ligand to stimulate its own synthesis and that of its receptor suggests the presence of an autocrine positive feedback loop, however we were unable to break this loop in the breast cancer cells by antibodies that blocked the interaction of TGF alpha with the EGF receptor. The ability of EGF to stimulate EGF receptor and TGF alpha expression appears to require protein kinase C, since inhibition of this enzyme blocked the ability of EGF to stimulate these genes. These studies raise the possibility that hormones capable of activating protein kinase C could stimulate EGF receptor and TGF alpha expression.     

Growth inhibitory effect of N-(phosphonacetyl)-L-aspartic acid on human myeloid leukemia-derived cell lines and modulation by dipyridamole

Dipyridamole (DIP) inhibited the uptake of tritiated thymidine (TdR), deoxyuridine (UdR) and uridine (UR) in myeloid leukemia-derived cell lines, PL-21 and KCL-22. DIP also inhibited the growth of PL-21 (50% inhibitory concentrations, IC50, 15 microM) and KCL-22 (IC50, 3.0 microM). PALA inhibited the growth of PL-21 (IC50, 68 microM) and KCL-22 (IC50, 62 microM). The growth inhibition by PALA was significantly enhanced by the addition of 1 microM (PL-21) and 0.1 microM (KCL-22) of DIP. The inhibitory effect of PALA or PALA with DIP was completely abolished by the addition of 50 microM of UR in both cell cultures. Clinical evaluation of PALA in combination with DIP is warranted for the treatment of myeloid leukemia.     

TGFβ-induced fibrogenesis of the pancreas

The biological cause of fibrosis is the accumulation of excessive amounts of extracellular matrix (ECM) which leads to tissue dysfunction and organ failure. A strong correlation can be found between pancreatic diseases and fibrotic processes, in particular chronic pancreatitis and pancreatic cancer. There is growing evidence that pancreatic fibrosis represents a dysregulation of the normal repair processes after injury. This concept is based on the findings that fibrosis and tissue repair involve similar biological reactions regulated by the same group of molecules. The best characterized example for these regulatory molecules are the members of the transforming growth factor beta family (TGFβ). TGFβ1 represents the prototype of this family of highly similar growth factors, with the unique ability to stimulate the expression and deposition of extracellular matrix and to inhibit its degradation. Growth factor-induced fibrotic events are targeted by a myofibroblast-like cell called pancreatic stellate cell (PSC). These cells show enhanced expression of all-important ECM proteins after TGFβ stimulation including collagen, fibronectin and proteoglycans. At the same time TGFβ inhibits the degradation of ECM by blocking the secretion of proteases and stimulating the production of naturally occurring protease inhibitors.     

Growth inhibitory effects of diallyl disulfide on human breast cancer cell lines

Diallyl disulfide (DADS) is an oil-soluble organosulfur compound found in garlic. The effect of synthetic DADS on the growth of estrogen receptor (ER)-positive (KPL-1 and MCF-7) and -negative (MDA-MB-231 and MKL-F) human breast cancer cell lines was examined. In an in vitro MTT assay, regardless of ER status, DADS at an IC(50) of 1.8-18.1 microM after 72 h incubation caused inhibition of growth in all four cell lines examined. Growth inhibition was due to apoptosis as seen by the appearance of a sub G1 fraction. In MDA-MB-231 cells, the apoptosis cascade comprised up-regulation of Bax protein (142%), down-regulation of Bcl-X(L) protein (38%) and activation of caspase-3 (438%) compared with controls. In an in vivo assay by orthotopic (right thoracic mammary fat pad) transplantation of KPL-1 cells in female nude mice, intraperitoneal injection of 1 or 2 mg DADS three times a week from the day of tumor cell inoculation until the end of the experiment (after 35 days) caused growth retardation and 43% reductions in primary tumor weight, respectively, compared with DADS-untreated mice without apparent side effects. Cell proliferation as evaluated by proliferating cell nuclear antigen (PCNA)-labeling in transplanted tumor of DADS-untreated mice was 59.6%, and 1 and 2 mg DADS-treated mice was 44.6 and 44.5%, respectively. In MDA-MB-231 cells, DADS antagonized the effect of linoleic acid (LA), a potent breast cancer cell stimulator (at DADS = 1.8 microM and LA > or = 6.5x10(2) microM concentration), and synergized the effect of eicosapentaenoic acid (EPA), a potent breast cancer cell suppressor (at DADS >3 x 10(-3) microM and EPA > 6.3 x 10(-1) microM concentration). Thus, DADS could be a promising anticancer agent for both hormone-dependent and -independent breast cancers, and may harmonize with polyunsaturated fatty acids known as modulators of breast cancer cell growth.     

Growth inhibitory effect of alk(en)yl thiosulfates derived from onion and garlic in human immortalized and tumor cell lines

Two alk(en)yl thiosulfates, sodium n-propyl thiosulfate (NPTS) and sodium 2-propenyl thiosulfate (2PTS), are natural constituents of onion and garlic, respectively, which were identified originally as causative agents of onion- and garlic-induced hemolytic anemia in dogs. As a continuation of our studies on the beneficial functions of NPTS and 2PTS, in the present study, we investigated the antitumor effects of these compounds. They were shown to inhibit the in vitro proliferation of three human tumorigenic cell lines, WiDr, 293 and HL-60, in a dose-dependent manner. Overall, NPTS seemed to have weak activity for inhibiting cell growth compared with 2PTS, though not in WiDr cells, which were sensitive to both compounds. NPTS and 2PTS caused oxidative damage to HL-60 cells and induced apoptosis. The extent of apoptosis was approximately proportional to that of the oxidative damage and also to that of the cytotoxicity caused by these compounds. These results suggest that the alk(en)yl thiosulfates have an antitumor effect through the induction of apoptosis initiated by oxidative stress.     

TGF-α与绿脓杆菌外毒素融合蛋白的表达、纯化及对肿瘤细胞的杀伤作用

目的： 表达并纯化转化生长因子α与绿脓杆菌外毒素融合蛋白（TGFαPE40）,探讨其对EGF受体（EGFR）阳性肿瘤细胞的靶向杀伤作用。方法：用pET28a表达载体构建表达TGFαPE40蛋白的重组体pV28,IPTG诱导其表达后,提取包涵体蛋白并用Ni柱纯化,MTT法观察复性融合蛋白对肿瘤细胞A431和SKOV3的杀伤效用。结果：成功构建基因重组质粒pV28,纯化后的包涵体蛋白中TGFαPE40蛋白纯度达98％以上,这种活性毒素蛋白对EGFR高表达的A431癌细胞抑制率为50％（IC50）时所需蛋白浓度为(0.86±0.07)μg/ml,低于EGFR低表达的SKOV3癌细胞的IC50 (6.37±2.18μg/ml),差异显著（P<0.05）。结论： 融合蛋白 TGFαPE40 对肿瘤细胞的毒性与肿瘤细胞表面表达的EGFR数量成正相关,可选择性杀伤肿瘤细胞。