Silibinin causes apoptosis and cell cycle arrest in some human pancreatic cancer cells

Silibinin, an effective anti-cancer and chemopreventive agent in various epithelial cancer models, has been reported to inhibit cancer cell growth through mitogenic signaling pathways. However, whether it can inhibit human pancreatic carcinoma growth and what are the underlying mechanisms is still not well elucidated. Here, we evaluated the inhibitory proliferation effects of Silibinin in pancreatic carcinoma growth and examined whether Silibinin modulates cell cycle and apoptosis. Our results indicate that Silibinin effectively inhibited the pancreatic carcinoma AsPC-1, BxPC-3 and Panc-1 cells' proliferation and caused apoptosis. Silibinin induced a decrease in S phase and cell cycle arrest in G1 phase in AsPC-1 cells, but had no obvious changes in BxPC-3 and Panc-1 cell cycle. Furthermore, these results suggest that Silibinin might be a candidate chemopreventive agent for pancreatic carcinoma therapy.     

Effect of tocotrienols on the growth of a human breast cancer cell line in culture

The tocotrienol-rich fraction (TRF) of palm oil consists of tocotrienols and some α-tocopherol (α-T). Tocotrienols are a form of vitamin E having an unsaturated side-chain, rather than the saturated side-chain of the more common tocopherols. Because palm oil has been shown not to promote chemically-induced mammary carcinogenesis, we tested effects of TRF and α-T on the proliferation, growth, and plating efficiency (PE) of MDA-MB-435 estrogen-receptor-negative human breast cancer cells. TRF inhibited the proliferation of these cells with a concentration required to inhibit cell proliferation by 50% of 180 μg/mL, whereas α-T had no effect at concentrations up to 1000 μg/mL as measured by incorporation of [³H]thymidine. The effects of TRF and α-T also were tested in longer-term growth experiments, using concentrations of 180 and 500 μg/mL. We found that TRF inhibited the growth of these cells by 50%, whereas α-T did not. Their effect on the ability of these cells to form colonies also was studied, and it was found that TRF inhibited PE, whereas α-T had no effect. These results suggest that the inhibition is due to the presence of tocotrienols in TRF rather than α-T. Based on a paper presented at the PORIM International Palm Oil Congress (PIPOC) held in Kuala Lumpur, Malaysia, September 1993.     

Wogonin induces reactive oxygen species production and cell apoptosis in human glioma cancer cells

Glioma is the most common primary adult brain tumor with poor prognosis because of the ease of spreading tumor cells to other regions of the brain. Cell apoptosis is frequently targeted for developing anti-cancer drugs. In the present study, we have assessed wogonin, a flavonoid compound isolated from Scutellaria baicalensis Georgi, induced ROS generation, endoplasmic reticulum (ER) stress and cell apoptosis. Wogonin induced cell death in two different human glioma cells, such as U251 and U87 cells but not in human primary astrocytes (IC 50 > 100 μM). Wogonin-induced apoptotic cell death in glioma cells was measured by propidine iodine (PI) analysis, Tunnel assay and Annexin V staining methods. Furthermore, wogonin also induced caspase-9 and caspase-3 activation as well as up-regulation of cleaved PARP expression. Moreover, treatment of wogonin also increased a number of signature ER stress markers glucose-regulated protein (GRP)-78, GRP-94, Calpain I, and phosphorylation of eukaryotic initiation factor-2α (eIF2α). Treatment of human glioma cells with wogonin was found to induce reactive oxygen species (ROS) generation. Wogonin induced ER stress-related protein expression and cell apoptosis was reduced by the ROS inhibitors apocynin and NAC (N-acetylcysteine). The present study provides evidence to support the fact that wogonin induces human glioma cell apoptosis mediated ROS generation, ER stress activation and cell apoptosis.     

Sorafenib loaded pluronic F127-lithocholic acid micelles for prostate cancer therapy: Formulation,optimization, and in vitro evaluation against LNCaP cells

Abstract

In present study, sorafenib loaded nanomicelles were prepared with synthesized pluronic F127 - lithocholic acid by film hydration method. The optimized micelles were spherical showing particle size of 319.36?nm, zeta potential of -11.96?mV, encapsulation efficiency of 87.31%, loading efficiency of 14.87% and release efficiency of 30.1%. Sorafenib loaded nanomicelles showed negligible hemolysis activity on RBC, indicating excellent hemocompatibility of pluronic F127 - lithocholic acid. The drug free nanomicelles showed no cytotoxicity against L929 cells by using MTT assay. However, micellar sorafenib showed more anti-proliferation effect on LNCaP and DU145 cells as compared with free sorafenib.     

Survivin基因干扰和过表达对人乳腺癌MCF-7细胞凋亡的影响

目的观察凋亡抑制蛋白Survivin基因干扰和过表达对人乳腺癌MCF-7细胞凋亡的影响。方法将Survivin基因shRNA干扰质粒和过表达质粒pcDNA3.1-GFP-Survivin在脂质体介导下转染MCF-7细胞,并设空白对照组和脂质体对照组,转染后48 h,荧光显微镜下观察转染效率;荧光定量RT-PCR法检测转染细胞中Survivin基因mRNA的转录水平;MTT法检测转染细胞的凋亡率。结果转染MCF-7细胞后48 h,Survivin基因RNAi质粒和过表达质粒的转染效率为50%～60%;shRNA质粒转染组MCF-7细胞中Survivin基因mRNA的转录水平明显低于空白对照组和脂质体对照组,而过表达质粒转染组明显高于空白对照组和脂质体对照组(P<0.05);shRNA质粒转染组MCF-7细胞的凋亡率明显高于空白对照组和脂质体对照组,而过表达质粒转染组明显低于空白对照组和脂质体对照组(P<0.05)。结论 Survivin基因对人乳腺癌MCF-7细胞的凋亡具有一定的抑制作用,可作为人乳腺癌生物治疗的候选基因。     

大豆多肽对前列腺癌PC-3细胞增殖及凋亡的影响

目的探讨大豆多肽对前列腺癌PC-3细胞增殖及凋亡的影响,为临床应用大豆多肽治疗前列腺癌提供实验依据。方法用不同浓度的大豆多肽(5、10、15、20μmol/L)处理前列腺癌PC-3细胞不同时间(24、48、72 h),采用MTT法检测细胞的增殖活力,倒置显微镜观察细胞的形态,流式细胞术检测细胞凋亡率及细胞周期。结果大豆多肽可抑制前列腺癌PC-3细胞的增殖,将细胞周期阻滞在G2/M期,诱导细胞凋亡,中晚期细胞凋亡趋势明显,且呈明显的剂量与时间依赖性;随着大豆多肽浓度的增加,前列腺癌PC-3细胞密度逐渐降低,边缘趋于圆滑,细胞间隙逐渐增大,局部可见部分已固缩的细胞及死亡的细胞碎片。结论大豆多肽可抑制前列腺癌PC-3细胞增殖,诱导细胞凋亡,在临床治疗前列腺癌方面具有广阔的应用前景。     

Derivatives of Iressa, a specific epidermal growth factor receptor inhibitor, are powerful apoptosis inducers in PC3 prostatic cancer cells

The tyrosine kinase activity of the epidermal growth factor receptor (EGFR) is widely involved in signaling pathways and often deregulated in cancer. Its role in the development of prostate cancer is well established, and therapeutic strategies such as blockade of the intracellular tyrosine kinase domain with small-molecule tyrosine kinase inhibitors have been proposed. Herein we describe the synthesis and in vitro pharmacological properties of C6- and C7-substituted 4-anilinoquinazolines, analogues of Iressa and powerful proapoptotic inducers in hormone-independent prostate cancer PC3 cell lines.     

Stability of Minor Lipid Components with Emphasis on Phytosterols During Chemical Interesterification of a Blend of Refined Olive Oil and Palm Stearin

Minor compounds such as tocopherols and phytosterols in vegetable oils play an important role in their stability and nutritional value. This study monitored the effects of chemical interesterification on the levels of tocopherols, tocotrienols, phytosterols and phytosterol oxidation products (POPs) in an olive oil and palm stearin blend (50/50 w/w). Tocopherols and tocotrienols were dominated by α-tocopherol (192 ppm) and γ-tocotrienol (70 ppm) and decreased during interesterification. Among the tocopherols, δ-tocotrienol had the highest decrease (35%) at 120 °C. During interesterification at 90 and 120 °C, total sterol content in the oil blend (509 ppm) declined slightly, by 3 and 5%, respectively. Phytosterols were esterified at a higher level at 120 °C (7%) than at 90 °C (4%) during this process. Distribution of fatty acids in the esterified sterols followed the fatty acid composition of the oil blend. Total POP content was 4.3 ppm, and remained generally unchanged during interesterification. Among the nine POPs tentatively identified by their mass spectra, 6-hydroxysitostanol and 6-hydroxycampestanol dominated in the oil blend and in the interesterified product. The formation pathways of these saturated di-hydroxyphytosterols have yet to be identified. Although the interesterification process comprised several treatments, there were only minor losses of tocopherols and phytosterols and virtually no increases in the POPs.     

RNA干扰整合素连接激酶基因表达对人舌鳞癌Tb细胞生长、迁移和侵袭能力的影响

目的探讨沉默整合素连接激酶(integrin-linked kinase,ILK)基因表达对人舌鳞癌Tb细胞生长、迁移和侵袭能力的影响。方法将ILK siRNA表达质粒和阴性对照质粒在脂质体介导下转染人舌鳞癌Tb细胞,稳定表达细胞株分别命名为Tb siILK和Tb vector组,并设正常Tb细胞对照组(Tb组)。Western blot法检测细胞中ILK蛋白的表达;细胞免疫荧光法检测细胞中ILK、p-Akt和p-GSK3β的表达;光镜和HE染色观察细胞的形态学变化;划痕试验检测细胞的迁移能力;Transwell法检测细胞的侵袭能力;流式细胞术检测细胞的细胞周期和凋亡情况;MTT法检测细胞的增殖活力;Western blot法检测沉默ILK基因后细胞中p-Akt、Akt、p-GSK3β、GSK3α/β、Snail的表达。结果与Tb和Tb vector组相比,Tb siILK组细胞中ILK蛋白的表达水平显著降低(P<0.01);ILK、p-Akt、p-GSK3β在胞质中的荧光信号明显减弱;大部分细胞的上皮形态特征更为明显;细胞的迁移距离和侵袭细胞数显著减少(P<0.05);G2-M期和G0-G1期细胞比例均显著增加(P<0.01);细胞的增殖活力显著减低;ILK基因沉默后,细胞中p-Akt、p-GSK3β和Snail蛋白的表达水平显著降低(P<0.05)。3组细胞的凋亡率差异无统计学意义(P>0.05)。结论抑制ILK基因的表达可通过Akt/GSK3β/Snail途径显著抑制人舌鳞癌Tb细胞的生长、迁移和侵袭能力,ILK有望作为治疗人舌鳞癌的靶基因。     

T-cadherin基因在前列腺癌组织中的表达及其对前列腺癌细胞DU145增殖的影响

目的探讨T-cadherin基因在前列腺癌组织中的表达及其对前列腺癌细胞DU145增殖的影响。方法采用RT-PCR法检测40份前列腺癌及相应癌旁组织中T-cadherin基因mRNA的表达。分别用10 ml滴度为1.6×10~(12)pdf/ml的GFP-T-cadherin腺病毒(Ad-GFP-T-cadherin)和GFP腺病毒(Ad-GFP)感染前列腺癌DU145细胞后,MTT法检测T-cadherin对前列腺癌DU145细胞增殖的影响,Western blot法检测T-cadherin对P21和cyclin D1蛋白表达水平的影响,同时设空白对照组(未感染病毒)。结果 T-cadherin在38/40(95%)的前列腺癌中表达下调(P0.01),其表达与前列腺癌的分期、格里森评分及分化有关。Ad-GFP-T-cadherin组DU145细胞中P21蛋白表达水平明显高于Ad-GFP组及空白对照组(P0.01),而cyclin D1蛋白表达水平及增殖活性明显低于Ad-GFP组及空白对照组(P0.01);空白对照组DU145细胞的增殖活性及细胞中P21、cyclin D1蛋白表达水平与Ad-GFP组比较,差异无统计学意义(P0.05)。结论 T-cadherin的表达与前列腺癌的发生密切相关,且可通过上调P21和下调cyclin D1蛋白的表达抑制前列腺癌DU145细胞的增殖。     

乳癌组织中人类表皮生长因子受体2蛋白的纯化及鉴定

目的建立乳腺癌组织中人类表皮生长因子受体2(human epidermal growth factor receptor 2,HER2)蛋白的纯化方法。方法采用新鲜的乳腺癌组织制备匀浆液,经60%饱和硫酸铵盐析沉淀法进行乳腺癌组织蛋白的粗提;再通过DEAE-Sephadex A-50离子交换层析和两次Sephacryl S-200分子筛层析进一步纯化HER2蛋白;纯化蛋白进行SDS-PAGE和Western blot鉴定。结果纯化后HER2蛋白相对分子质量为185 000;HER2蛋白可与兔抗人HER2多克隆抗体发生特异性结合。结论建立的纯化方法获得了具有免疫学活性的HER2蛋白,为HER2单克隆抗体的制备奠定了基础。     

联氨基姜黄素对乳腺癌细胞MCF-7增殖和凋亡的影响及其机制

目的探讨联氨基姜黄素对人乳腺癌细胞MCF-7增殖和凋亡的影响及其机制。方法采用MTT法检测联氨基姜黄素对MCF-7细胞的抗增殖效应,Hochest33258染色观察细胞形态学变化,流式细胞术分析细胞的周期分布和凋亡情况,Western blot检测MCF-7细胞中Bcl-2、Bax、Cyclin D1和Survivin蛋白的表达变化。结果联氨基姜黄素可抑制MCF-7细胞的增殖,IC50为2.56μmol/L,而姜黄素的IC50为21.22μmol/L;联氨基姜黄素染色24 h后,MCF-7细胞出现核荧光强度增强、颗粒状荧光等凋亡特征;凋亡细胞比率明显增加,并可阻滞细胞周期于G1期,且呈一定的剂量依赖性;联氨基姜黄素可使MCF-7细胞中Bcl-2、Cyclin D1、Survivin蛋白表达水平明显降低,而Bax表达增加。结论联氨基姜黄素具有抑制MCF-7细胞增殖、促进凋亡、阻滞细胞周期于G1期的作用,其机制可能与Bcl-2、Bax、Cyclin D1、Survivin蛋白的表达改变有关。     

野生型着丝粒蛋白-E基因沉默对人结肠癌HCT116细胞增殖、凋亡、迁移和侵袭能力的影响

目的利用RNA干扰技术下调野生型着丝粒蛋白E(Wild type centromere protein E,CENP-EWT)基因的表达,观察CENP-EWT基因沉默对结肠癌HCT116细胞增殖、凋亡、迁移和侵袭能力的影响。方法将HCT116细胞分为空白对照组、空载体转染组和CENP-EWT shRNA转染组,转染48 h后,采用巢式PCR检测细胞中CENP-EWT基因mRNA的转录水平;MTT法检测细胞的增殖活力;Hoechst法检测细胞的凋亡比例;Transwell小室试验检测细胞的迁移和侵袭能力。结果与空白对照组和空载体转染组相比,CENP-EWT shRNA转染组可有效抑制CENP-EWT基因的转录水平(P<0.05);CENP-EWT shRNA转染组细胞的增殖活力明显下降(P<0.05);细胞凋亡比例明显增加(P<0.01),细胞的迁移和侵袭能力明显增强(P<0.01)。结论 CENP-EWT基因沉默能够抑制人结肠癌HCT116细胞增殖,诱导细胞凋亡,但同时能增强细胞的迁移和侵袭能力。     

The compound 13-D selectively induces apoptosis in white blood cancers versus other cancer cell types

As general cytotoxins are still the backbone of anticancer chemotherapy, the identification of selective inducers of cell death in defined cancer types and subtypes is one of the major goals of modern oncology research. Thus, compounds identified with such selectivity have utility as probes of cancer-type-specific biological pathways, and optimized versions have potential in targeted anticancer therapy. Described herein is the discovery that compound 13-D selectively induces apoptotic cell death in white blood cancer cell lines but not in other cancer cell lines. Further experiments indicate that this selectivity is not simply due to selective cell permeability. The compound localizes to both the nucleus and cytoplasm and arrests cells in the prophase/prometaphase of the cell cycle, and there is a very sharp dependence of activity on compound structure, with the trans-alpha,beta-unsaturated amide of 13-D being critical for inducing cell death. The macromolecular target of 13-D could be involved in white blood cell-specific oncogenic pathways.     

丹皮酚对人卵巢癌SKOV3细胞凋亡的影响及其可能的机制

目的探讨丹皮酚对人卵巢癌SKOV3细胞的促凋亡作用及其可能的机制。方法用25、50、100、200、400μg/ml丹皮酚处理SKOV3细胞,设未经丹皮酚处理的细胞为对照组,24 h后,采用MTT法检测细胞增殖情况;用50、100、200μg/ml丹皮酚处理SKOV3细胞,设未经丹皮酚处理的细胞为对照组,24 h后,采用流式细胞术(flow cytometry,FCM)、Hoechst染色法检测细胞凋亡情况,Western blot法检测caspase3及survivin蛋白的表达情况。结果与对照组相比,各浓度丹皮酚对SKOV3细胞的增殖均有明显的抑制作用,呈浓度依赖性(P<0.05),IC50值为200.06μg/ml;100、200μg/ml浓度组中SKOV3细胞凋亡率分别为(35.33±1.32)%、(39.56±1.27)%,与对照组[(9.01±1.21)%]相比明显增加(P<0.05);丹皮酚100、200μg/ml浓度组中发生凋亡的细胞数量较对照组多;丹皮酚处理后细胞凋亡相关蛋白survivin表达降低,而caspase3表达增加,高浓度组与低浓度组相比,差异均有统计学意义(P<0.05)。结论丹皮酚能显著抑制人卵巢癌SKOV3细胞增殖,促进细胞凋亡,其机制可能与其调控凋亡相关蛋白survivin、caspase3表达变化有关。