4-Methyl-3-nitro-benzoic acid,a migration inhibitor,prevents breast cancer metastasis in SCID mice

Metastasis remains a formidable problem in malignant tumors. In this study, MTT assay revealed that 4-methyl-3-nitro-benzoic acid (MNBA) had no effect on cell viability and did not interfere with cell cycle in any breast cancer cell lines tested. However, treatment with MNBA on breast cancer cells can inhibit EGF-induced migration and chemotaxis in vitro. In vivo assay demonstrated that MNBA and Paclitaxel synergistically inhibited tumor growth and metastasis in breast cancer SCID mice xenografts. These results suggest that MNBA is a potent inhibitor cancer cell chemotaxis and may be developed into a novel anti-metastasis drug.     

舒林酸对胃癌细胞株SGC7901细胞周期调控及凋亡的影响

目的观察舒林酸影响胃癌细胞株SGC7901细胞周期分布,诱导细胞凋亡,探讨其作用机制方法采用MTT比色法观察舒林酸对胃癌SGC7901细胞增殖的影响,采用流式细胞仪检测舒林酸对细胞周期分布的影响,同时结合透射电子显微镜观察舒林酸诱导SGC901细胞凋亡的作用;免疫细胞化学方法观察舒林酸对胃癌细胞周期调控蛋白cyvclinE及P21WAF/CIPI的影响结果舒林酸可抑制胃癌SGC7901细胞的增殖,改变细胞周期分布,使G-0/G1期细胞比例增高,S期比例降低,并对SGC7901细胞有促凋亡作用.上述作用具有剂量和时间依赖性(P＜0.05).舒林酸还可上调P21WAF/CIPI蛋白表达.下调cyolinE蛋白表达.结论舒林酸可改变细胞周期分布,影响细胞周期调控蛋白表达,并可诱导SGC7901细胞凋亡,从而抑制细胞增殖.     

胃癌细胞ｐ１６和ＣＤＫ４的表达及调控的分子机制

目的　通过腺病毒携带ｐ１６基因感染胃癌细胞,研究ｐ１６功能恢复对ＣＤＫ４表达的调节作用。方法　构建携带ｐ１６基因的重组腺病毒ＡｄＣＭＶ-ｐ１６感染胃癌细胞系。Ｗｅｓｔｅｒｎｂｌｏｔｔｉｎｇ检测ｐ１６和ＣＤＫ４的表达,ＭＴＴ法检测癌细胞的增殖活性,ＤＡＰＩ染色计数癌细胞的凋亡比例。结果　胃癌细胞感染腺病毒载体ＡｄＣＭＶ-ｐ１６后获得ｐ１６表达,对细胞整体ＣＤＫ４表达无影响,但可明显降低细胞核ＣＤＫ４的表达量;ＡｄＣＭＶ-ｐ１６感染后引起癌细胞增殖活性下降,当感染复数（ＭＯＩ）为１、１０、２０时,细胞存活率已经分别低于５０％、２０％和５％;ｐ１６表达可诱导癌细胞凋亡,细胞凋亡率达（１３.８６±４.６５）％。结论　ｐ１６功能恢复后核ＣＤＫ４含量减少,可能是诱导细胞周期阻滞和细胞凋亡、抑制癌细胞生长的主要分子机制。     

Tumor-targeting Salmonella typhimurium A1-R prevents experimental human breast cancer bone metastasis in nude mice

Bone metastasis is a lethal and morbid late stage of breast cancer that is currently treatment resistant. More effective mouse models and treatment are necessary. High bone-metastatic variants of human breast cancer cells were selected in nude mice by cardiac injection. After cardiac injection of a high bone-metastatic variant of breast cancer, all untreated mice had bone metastases compared to only 20% with parental cells. Treatment with tumor-targeting Salmonella typhimurium A1-R completely prevented the appearance of bone metastasis of the high metastatic variant in nude mice (P < 0.001). After injection of the highly bone-metastatic breast cancer variant to the tibia of nude mice, S. typhimurium A1-R treatment significantly reduced tumor growth in the bone (P < 0.001). These data indicated that S. typhimurium A1-R is useful to prevent and inhibit breast cancer bone metastasis and should be of future clinical use for breast cancer in the adjuvant setting.     

Downregulation of gastrokine-1 in gastric cancer tissues and restoration of its expression induced gastric cancer cells to apoptosis

ABSTRACT: BACKGROUND: Gastrokine-1 (GKN1), a secreted protein, is specifically expressed in gastric mucosa to protect and maintain the integrity of gastric epithelium. The present study investigated differential expression of GKN1 in normal, precancerous, and cancerous gastric tissues, and explored the biological functions of GKN1 protein in gastric cancer cells. METHODS: RT-PCR, Western blot, and immunohistochemistry were performed to detect GKN1 expression in normal, precancerous, cancerous gastric tissues and seven gastric cancer cell lines. Gene transfection was used to restore GKN1 expression in gastric cancer AGS cells. Phenotypic changes (i.e., cell viability, apoptosis, cell cycle modulation, and sensitivity of gastric cancer cells to fluorouracil (5-FU)) were assayed in the transfected cells. DNA microarrays were used to analyze expression changes of apoptosis-related genes. RESULTS: Significant downregulation or absence of GKN1 expression in seven gastric cancer cell lines were detected and progressive decrease of GKN1 expression from normal mucosa, precancerous tissue, to cancer tissues was observed. Moreover, restoration of GKN1 expression suppressed gastric cancer cell viability and induced the cells to undergo apoptosis. GKN1 expression also enhanced tumor cell sensitivity to 5-FU treatment. Moreover, it was found that GKN1 expression in AGS cells modulated expression of 19 apoptosis-related genes. CONCLUSIONS: Expression of GKN1 is progressively lost from normal mucosa, precancerous to cancerous gastric tissues, while restoration of GKN1 expression induces gastric cancer cells to undergo apoptosis, and enhances sensitivity of gastric cancer cells to 5-FU-induced apoptosis.     

The apoptotic effect of cordycepin on human OEC-M1 oral cancer cell line

Cordycepin (3′-deoxyadenosine), a pure compound of Cordyceps sinensis, has been illustrated with anti-tumor effects. In the present study, the apoptotic effect of cordycepin on OEC-M1, a human oral squamous cancer cell line, was investigated by morphological observations, cell viability assay, annexin V-FITC analysis and flow cytometry methods. Results demonstrated that the number of rounded-up cell increased as treatment duration of cordycepin (100 μM) increased from 3 to 48 h, and the plasma membrane blebbing could be observed after 12 h treatment. In cell viability assay, cell surviving rate significantly decreased as the dosage and duration of cordycepin treatment increased (P < 0.05). Moreover, phosphatidylserine flipping on cell membrane could be detected with 3, 6 and 12 h cordycepin treatment, which indicated an early apoptotic phenomenon. Furthermore, cell cycle studies illustrated that the percentage of G1 phase cell declined as the dosages of cordycepin increased (10 μM to 5 mM), while the percentages of G2M and subG1 phase cell increased (P < 0.05) in 12, 24 and 48 h cordycepin treatment. These results further confirmed the apoptotic event. In conclusion, cordycepin significantly induced cell apoptotsis in OEC-M1 human oral squamous cancer cells. Wei-Ciao Wu and Jenn-Ren Hsiao contributed equally.     

SK-7041, a new histone deacetylase inhibitor, induces G2-M cell cycle arrest and apoptosis in pancreatic cancer cell lines

A novel hybrid synthetic histone deacetylase inhibitor, SK-7041, was synthesized from hydroaxamic acid of trichostatin A (TSA) and pyridyl ring of MS-275. TSA and SK-7041 both induced apoptosis and G2-M cell cycle arrest in pancreatic cancer cell lines. The expressions of p21 and cyclin D2 were up-regulated and that of cyclin B1 was down-regulated by TSA or SK-7041. The expression levels of Mcl-1 and Bcl-XL but not those of Bcl-2, Bax, and Bak were suppressed by TSA or SK-7041 treatment. SK-7041 or TSA induced apoptosis and G2-M cell cycle arrest by up-regulating p21 and down-regulating cyclin B1, Mcl-1, and Bcl-XL.     

KRC-408, a novel c-Met inhibitor,suppresses cell proliferation and angiogenesis of gastric cancer

Among many cancer therapeutic targets, c-Met receptor tyrosine kinase has recently given particular attention. This kinase and its ligand, hepatocyte growth factor (HGF), play a central role in cell proliferation and the survival of several human cancers. Thus, we developed KRC-408 as a novel c-Met inhibitor and investigated its anti-cancer effects on human gastric cancer. KRC-408 inhibited the phosphorylation of c-Met and its constitutive downstream effectors such as phosphatidylinositol 3-kinase (PI3K), Akt, Mek, and Erk. This compound was found to exert anti-cancer effects stronger than those of 5-fluorouracil (5-FU) on gastric cancer cells, especially cell lines that overexpressed c-Met. Interestingly, cytotoxicity of KRC-408 was lower than that of 5-FU in normal gastric cells. Apoptosis induced by KRC-408 was accompanied by increased levels of cleaved caspase-3 and PARP as well as DNA condensation and fragmentation. Flow cytometry analysis showed an accumulation of gastric cancer cells in the G2/M phase with concomitant loss of cells in the S phase following treatment with this drug. In the angiogenesis studies, KRC-408 inhibited tube formation and migration of human umbilical vein endothelial cells (HUVECs), and suppressed microvessel sprouting from rat aortic rings ex vivo along with blood vessel formation in a Matrigel plug assay in mice. Results of an in vivo mouse xenograft experiment showed that the administration of KRC-408 significantly delayed tumor growth in a dose-dependent manner, and suppressed Akt and Erk phosphorylation as well CD34 expression in tumor tissues. These findings indicate that KCR-408 may exert anti-tumor effects by directly affecting tumor cell growth or survival via the c-Met receptor tyrosine kinase pathway. We therefore suggest that KRC-408 is a novel therapeutic candidate effective against gastric cancers that overexpress c-Met.     

Hyaluronidase reduces human breast cancer xenografts in SCID mice

A hyaluronan-rich environment often correlate with tumor progression. and may be one mechanism for the invasive behavior of malignancies. Eradication of hyaluronan by hyaluronidase administration could reduce tumor aggressiveness and would provide, therefore, a new anti-cancer strategy. Hyaluronan interaction with its CD44 receptor and the resulting signal transduction events may be among the mechanisms for hyaluronan-associated cancer progression. We have shown previously that hyaluronidase treatment of breast cancer cells in vitro not only eradicates hyaluronan but also modifies expression of CD44 variant exons of tumor cells. We now determine if such effects occur in vivo and if it is accompanied by tumor regression. SCID mice bearing xenografts of human breast carcinomas were given intravenous hyaluronidase. Tumor volumes decreased 50% in 4 days. Tumor sections showed decreased hyaluronan. Intensity of staining for CD44s was not affected, whereas staining for specific CD44 variant exon isoforms was greatly reduced in residual tumors. Necrosis was not evident. Hyaluronidase, used previously as an adjunct in cancer treatment, presumably to enhance penetration of chemotherapeutic drugs, may itself have intrinsic anti-cancer activity. Removing peritumor hyaluronan appears to cause an irreversible change in tumor metabolism. Continuous hyaluronan binding to CD44 variant exon isoforms may also be required to stabilize inherently unstable isoforms that participate perhaps in tumor progression. Further investigation is required to confirm a cause and effect relationship between loss of hyaluronan, changes in CD44 variant exon expression and tumor reduction. If confirmed, hyaluronidase may provide a new class of anti-cancer therapeutics and one without toxic side effects.     

蛋白激酶C抑制剂Staurosporine对人胃癌细胞周期的影响

背景与目的:蛋白激酶C(proteinkinaseC,PKC)已成为一个潜在的有价值的抗肿瘤治疗靶点。本研究旨在探讨PKC抑制剂Staurosporine(ST)对人胃癌细胞株MGC-803和SGC-7901的增殖抑制、凋亡诱导及对其细胞周期的影响。方法:在用台盼蓝拒染法检测细胞增殖抑制率的基础上,通过细胞形态学观察凋亡小体,流式细胞仪检测细胞凋亡率及细胞周期变化。结果:ST抑制MGC-803细胞生长,24h的IC50为54ng/ml,48h的IC50为23ng/ml;ST抑制SGC-7901细胞的生长,24h的IC50为61ng/ml,48h的IC50为37ng/ml。40、60、100ng/mlST分别作用MGC-803细胞24h后,发现G0/G1期细胞分别为(23.6±1.8)%、(11.6±0.7)%、(3.3±0.2)%,而对照组为(54.3±3.1)%;G2/M期细胞分别为(22.6±4.0)%、(35.5±0.4)%、(36.8±5.5)%,而对照组为(13.5±0.2)%。40、60、100ng/mlST分别作用于SGC-7901细胞24h后,G0/G1期细胞分别为(27.1±1.4)%、(17.0±3.4)%,(13.7±0.7)%,而对照组为(52.5±4.4)%;G2/M期细胞分别为(21.9±2.6)%、(39.5±4.9)%、(38.4±3.1)%,而对照组为(13.5±2.2)%。实验组细胞与对照组比较,ST使两种细胞G0/G1期明显减少及G2/M期明显增加(P<0.01)。200ng/mlST作用24h后两种细胞的G1期前均出现明显的凋亡峰,可诱导细胞出现典型凋亡小体。结论:ST显著降     

PRMT5在胃癌中的表达及其对胃癌细胞增殖、凋亡、迁移能力的影响

背景与目的:蛋白精氨酸甲基转移酶5(protein arginine methyltransferase 5,PRMT5)是一种能调控细胞周期的酶,对细胞分裂周期有影响,可以通过调控细胞分裂周期影响细胞的增殖与凋亡。探讨PRMT5在胃癌中的表达及对胃癌细胞增殖、凋亡、迁移能力的影响。方法:采用蛋白质印迹法(Western blot)检测2016年5月-2019年1月在海南省肿瘤医院确诊为胃癌并进行手术治疗的患者的胃癌组织及其癌旁组织(距离癌组织>5 cm)标本(共88例)中的PRMT5的表达,分析PRMT5相对表达量与胃癌临床特征的关系;用PRMT5小干扰RNA(PRMT5-siRNA)和阴性对照(siRNA-NC)转染人胃癌细胞系SGC-7901,以未转染的SGC-7901细胞作为对照组。采用实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)和Western blot检测转染后细胞中PRMT5 mRNA表达和蛋白水平;采用细胞计数试剂盒-8(cell counting kit-8,CCK-8)检测细胞增殖;采用流式细胞术(flow cytometry,FCM)检测细胞凋亡;采用划痕实验检测细胞迁移能力;采用Transwell细胞侵袭实验检测细胞侵袭能力;采用Western blot检测cleaved caspase 3、磷脂酰肌醇3激酶(phosphoinositide 3-kinase,PI3K)、蛋白激酶B(protein kinase B,AKT)和磷酸化AKT(phosphorylated-AKT,p-AKT)蛋白表达。结果:PRMT5在胃癌组织中的表达高于癌旁组织(P<0.01);PRMT5表达水平与胃癌的病理学分级、分期、淋巴结转移有关(P均<0.05);转染后siRNA-NC组和对照组PRMT5 mRNA和蛋白表达量、胃癌细胞的增殖率、凋亡率、cleaved caspase 3、PI3K、AKT、p-AKT蛋白表达量、划痕愈合率、细胞侵袭数差异均无统计学意义(P>0.05),转染后siRNA-NC组和对照组PRMT5 mRNA和蛋白表达量、胃癌细胞增殖率、PI3K、p-AKT、AKT蛋白表达量、划痕愈合率、细胞侵袭数均高于PRMT5-siRNA组,而凋亡率、cleaved caspase 3低于PRMT5-siRNA组(P均<0.05)。结论:PRMT5在胃癌组织中表达明显升高,其表达水平与胃癌的发生、发展、转移恶化密切相关,下调PRMT5的表达可明显减弱胃癌细胞的增殖、迁移能力,同时促进胃癌细胞的凋亡。     

Bufalin, a traditional oriental medicine, induces apoptosis in human cancer cells

Bufalin is a traditional oriental medicines which induces apoptosis in some lines of human tumor cells. It constitutes the major digoxin-like immunoreactive component of Chan Su, obtained from the skin and parotid venom glands of toads. Bufalin is cardioactive C-24 steroids that exhibits a variety of biological activities, such as cardiotonic, anaesthetic, blood pressure stimulatory, respiratory and antineoplastic effects. In terms of its anti-tumor activity, bufalin has been demonstrated to inhibit the growth of tumors, such as endometrial and ovarian cancers. This commentary introduces biologic and therapeutic effects of bufalin in treating some cancers. The compound is able to mediate inhibition of cell growth, cell cycle arrest, apoptosis, and expression of genes related to the malignant phenotype in human cancer cells.     

三氧化二砷诱导卵巢癌OVCAR-3细胞周期阻滞及凋亡

目的探讨As2O3对卵巢癌细胞增殖的抑制作用及对细胞周期和凋亡的影响.方法采用MTT法及集落形成实验测定细胞的增殖活力,通过细胞形态学观察细胞分裂及凋亡,应用流式细胞仪进行细胞周期解析、凋亡及bcl-2蛋白表达的检测.结果As2O3呈剂量依赖性抑制OVCAR-3细胞增殖,抑制50%细胞生长的药物浓度(IC50)为2μmol/L.0.5～5μmol/L的As2O3作用7天,集落抑制率均在40%以上(P＜0.01).2μmol/L与5μmol/L的As2O3作用12 h后,细胞周期出现了G2/M期阻滞及亚二倍体凋亡峰,随着作用时间的延长,凋亡细胞随G2/M期细胞减少而逐渐增多.细胞形态学观察可见分裂期细胞及凋亡细胞明显增加.0.5～5μmol/L的As2O3均能下调bcl-2蛋白的表达.结论As2O3能够抑制卵巢癌OVCAR-3细胞的增殖,诱导M期阻滞及细胞凋亡.     

Induction of apoptosis and cell cycle arrest by a specific c-Jun NH2-terminal kinase (JNK) inhibitor, SP-600125, in gastrointestinal cancers

The c-Jun NH(2)-terminal kinase (JNK) is activated in several tumor cell lines. The aim of this study was to determine the effects of SP-600125, a specific JNK inhibitor, on the viability, apoptosis, cell cycle distribution of gastrointestinal cancer cells, and the potential anti-tumor mechanisms. Three gastric cancer cell lines, AGS, BCG-823 and MKN-45, and three colorectal cancer cell lines, SW1116, COLO205 and HT-29, were used. Cells were treated with SP-600125, and cell viability, apoptosis and cell cycle distribution, caspase-3 activity, expression of JNK and apoptosis related proteins were detected. SP-600125 inhibited cell proliferation by 10-80% for the different cell lines, and increased apoptosis by 1.5-4.5 folds for COLO205, BCG-823, MKN-45, AGS cells. Caspase-8 and caspase-3 were involved in the induction of apoptosis. SP-600125 caused G2/M cell cycle arrest and elevation of cyclin B1 and p27(kip). The differential response in cells to SP-600125 was associated with the basal level of phosphorylated JNK2. It is concluded that SP-600125 inhibits proliferation, induces apoptosis and causes cell cycle arrest in gastrointestinal cancer cells, indicating that JNK inhibitors have an anti-tumor effect and are potential therapeutic agents for cancers.     

A novel imidazopyridine analogue as a phosphatidylinositol 3-kinase inhibitor against human breast cancer

Potentiation of anti-breast cancer activity of an imidazopyridine-based PI3Kα inhibitor, HS-104, was investigated in human breast cancer cells. HS-104 shows strong inhibitory activity against recombinant PI3Kα isoform and the PI3K signaling pathway, resulting in anti-proliferative activity in breast cancer cells. It also induced cell cycle arrest at the G(2)/M phase as well as apoptosis. Furthermore, oral administration of HS-104 significantly inhibited the growth of tumor in SkBr3 mouse xenograft models. Therefore, HS-104 could be considered as a potential candidate for the treatment of human breast cancer.     

Inhibition of cell proliferation through cell cycle arrest and apoptosis by thio-Cl-IB-MECA, a novel A3 adenosine receptor agonist, in human lung cancer cells

Human A₃ adenosine receptor (A₃AR) agonists showed the anti-tumor activity in various in vitro and in vivo studies. The present study investigates the anti-proliferative effect of a novel adenosine analog 2-chloro-N⁶-(3-iodobenzyl)-4′-thioadenosine-5′-N-methyluronamide (thio-Cl-IB-MECA) in A549 human lung cancer cells. Thio-Cl-IB-MECA induced arrest of cell cycle progression in G0/G1 phase at lower concentrations (up to 20 μM) and apoptotic cell death at a higher concentration (80 μM), which were manifested by down-regulation of cyclin D1, c-myc, and CDK4, activation of caspase-3 and -9, and cleavage of poly(ADP-ribose) polymerase (PARP). The activation of Akt-mediated signaling was also inhibited by treatment with thio-Cl-IB-MECA. These data might suggest the potential therapeutic value of an adenosine analog in the treatment of human lung cancer.     

Induction of Apoptosis and Cell Cycle Arrest by Dorema Glabrum Root Extracts in a Gastric Adenocarcinoma (AGS) Cell Line

Objective: Dorema glabrum Fisch. & C.A. Mey is a perennial plant that has several curative properties. Anti-proliferative activity of seeds of this plant has been demonstrated in a mouse fibrosarcoma cell line. The aim of the present study was to evaluate cytotoxicity of D. glabrum root extracts in a human gastric adenocarcinoma (AGS) cell line and explore mechanisms of apoptosis induction, cell cycle arrest and altered gene expression in cancer cells. Materials and Methods: The MTT assay was used to evaluate IC50 values, EB/AO staining to analyze the mode of cell death, and flow cytometry to assess the cell cycle. Quantitative real-time polymerase chain reaction (qRT-PCR) amplification was performed with apoptosis and cell cycle-related gene primers, for cyclin D1, c-myc, survivin, VEGF, Bcl-2, Bax, and caspase-3 to determine alteration of gene expression. Results: Our results showed that n-hexane and chloroform extracts had greatest toxic effects on gastric cancer cells with IC50 values of 6.4 μg/ml and 4.6 μg/ml, respectively, after 72 h. Cell cycle analysis revealed that the population of treated cells in the G1 phase was increased in comparison to controls. Cellular morphological changes indicated induction of apoptosis. In addition, mRNA expression levels of Bax and caspase-3 were increased, and of bcl-2 survivin, VEGF, c-myc and cyclin D1 were decreased. Conclusion: Our study results suggest that D. glabrum has cytotoxic effects on AGS cells, characterized by enhanced apoptosis, reduced cell viability and arrest of cell cycling.     

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.