Downregulation of alpha-fetoprotein siRNA inhibits proliferation of SMMC-7721 cells

AIM: To study the function of α-fetoprotein (AFP) in SMMC-7721 hepatoma cells.METHODS: A hairpin siRNA expressing plasmid pSilencer3.0-H1-afp was constructed and transfected into SMMC-7721 cells with Lipofectamine 2000. The expression of AFP was monitored by real-time RT-PCR and immunoassays, its effect on SMMC-7721 cell proliferation and cell death was detected by MTT and fluorescenceactivated cell sorter (FACS).RESULTS: The AFP-siRNA expressing plasmid downregulated the expression of AFP obviously (about 34%), and inhibited SMMC-7721 cell proliferation, but did not induce apoptosis.CONCLUSION: Downregulation of AFP siRNA inhibits proliferation of SMMC-7721 cells, but cannot cause apoptosis.

Effects of cytotoxic T lymphocytes on hepatoma cell line SMMC-7721 induced by different subsets of dendritic cells in vitro

BACKGROUND: Dendritic cells (DCs) loaded with complex antigen are always used to induce cytotoxic T lymphocytes (CTLs) which have a specific anti-tumor activity. However, CTLs can assault autologous cells induced by DCs loaded with autologous antigen. This study aimed to explore how to weaken the autoimmune reaction induced by DC vaccine by combining mature DC (mDC) activating immunity and immature DC (imDC) leading to immune tolerance to make hepatocellular carcinoma (HCC) vaccine in vitro. METHODS: DC progenitors derived from human peripheral blood were assigned to two groups. One was cultured to mDC and pulsed with frozen-thawed antigen (FTA) of human HCC cell line SMMC-7721 cells (mDC group), and the other was cultured to imDC and pulsed with FTA of human liver cell line L-02 cells (imDC group). The morphology of DCs was monitored and cells phenotypes including HLA-DR, CD80, CD1α, CD83 were assayed by flowcytometry (FCM). The concentrations of interleukin-12 (IL-12) in the supernatant were assayed by ELISA. Methyl thiazolyl tetrazolium (MTT) was used to evaluate T cell proliferation induced by mDC and imDC and the killing rate of CTL induced by mDC and imDC respectively/together on SMMC-7721 and L-02 cells. RESULTS: Compared with the imDC group, the mDC group was characterized by the following: increased secretion of IL-12 (P【0.05); higher expression of HLA-DR, CDla, CD80, CD83; and stronger activity in stimulating proliferation of isogenic T cells (P【0.05). CTL induced by the mDC group had a significant killing response to SMMC-7721 as well as a higher killing rate for L-02 (P】0.05). CTL induced by mDC and imDC together had a higher killing response to SMMC-7721, but a lower killing rate for L-02(P【0.01). CONCLUSIONS: CTL induced by mDC and imDC together has a higher antigen-specific killing response in vitro than that induced by mDC alone. This may be of greater clinical value.

Positional and expressive alteration of prohibitin during the induced differentiation of human hepatocarcinoma SMMC-7721 cells

AIM： To explore the existence and distribution of prohibitin （PHB） in nuclear matrix and its co-localization with products of some related genes during the differentiation of human hepatocarcinoma SNMC-7721 cells. METHODS： The nuclear matrix of the SMMC-7721 cells cultured with or without 5 × 10^-3 mmol/L hexamethylene bisacetamide （HNBA） was selectively extracted. Western blot was used to analyze the expression of PHB in nuclear matrix; immunofluorescence microscope observation was used to analyze the distribution of PHB in cell. LCSM was used to observe the co-localization of PHB with products of oncogenes and tumor suppressor genes. RESULTS： Western blot analysis showed that PHB existed in the composition of nuclear matrix proteins and was down-regulated by HMBA treatment. Immunofluorescence observation revealed that PHB existed in the nuclear matrix, and its distribution regions and expression levels were altered after HMBA treatment. Laser scanning confocal microscopy revealed the co-localization between PHB and the products of oncogenes or tumor repression genes including c-los, c-myc, p53 and Rb and its alteration of distributive area in the cells treated by HMBA. CONCLUSION： These data confirm that PHB is a nuclear matrix protein, which is located in the nuclear matrix, and the distribution and expression of PHB and its relation with associated genes may play significant roles during the differentiation of SMMC-7721 cells.

α-干扰素对肝癌多药耐药株SMMC-7221/ADM的逆转及其机制研究

目的:研究α－干扰素对人肝癌多药耐药细胞株ＳＭＭＣ－７２２１/ＡＤＭ的逆转作用。方法:用ＭＴＴ法检测常用化疗药物对ＳＭＭＣ－７２２１/ＡＤＭ的毒性。用流式细胞仪(ＦＣＭ)检测ＳＭＭＣ－７２２１/ＡＤＭ细胞的Ｐ－糖蛋白(Ｐ－ｇｐ)的表达及细胞内柔红霉素的相对浓度。结果:α－干扰素可提高ＳＭＭＣ－７２２１/ＡＤＭ细胞内化疗药物的浓度,增加阿霉素等化疗药物对ＳＭＭＣ－７２２１/ＡＤＭ的毒性作用。结论:α－干扰素可逆转人肝癌多药耐药株ＳＭＭＣ－７２２１/ＡＤＭ。

复方苦参注射液对人肝癌SMMC-7221细胞体外增殖、转移和侵袭的抑制作用及其机制

目的探讨复方苦参注射液(CKI)对体外培养的人肝癌SMMC-7221细胞增殖、转移和侵袭的抑制作用及机制。方法用不同稀释百分比〔0.0%(细胞对照组),2.5%,5.0%和10.0%〕的CKI与SMMC-7221细胞共孵育24 h,分别采用MTT法检测细胞存活,采用划痕修复实验和Transwell实验观察细胞迁移和侵袭能力。用5.0%和10.0%的CKI处理SMMC-7221细胞12或24 h后,RT-PCR及Western印迹法分别检测细胞NF-κB mRNA和蛋白的表达水平。结果经2.5%,5.0%和10.0%CKI处理24 h后,SMMC-7221细胞存活率分别为细胞对照组的(92±8)%,(77±5)%(P<0.01)和(56±7)%(P<0.01);细胞迁移率分别为(90±7)%,(50±10)%(P<0.01)和(25±5)%(P<0.01);体外细胞侵袭率分别为(98±7)%,(51±10)%(P<0.01)和(20±5)%(P<0.01)。另外,5.0%和10.0%CKI处理细胞12 h后,NF-κB mRNA水平分别降低至细胞对照组的(42±9)%和(46±10)%(P<0.01),而5.0%和10.0%CKI处理24 h后,NF-κB蛋白表达水平分别降低至(67±16)%和(27±11)%(P<0.01)。结论 CKI具有抑制SMMC-7221细胞增殖、体外转移和侵袭的能力,其机制可能与抑制NF-κB信号通路有关。

Activity Determination of 8 Chinese Herbs against Hepatoma Cell SMMC-7721 in Vitro by MTT Method

[Objective] The aim was to build up a set of efficient and rapid models for laboratory to screen anti-hepatocellular carcinoma active substance in vitro. [ Method] By using MTT method, the activities of anti-hepatocellular carcinoma SMMC-7721 in vitro from Cymbopogon distans, Lobelia chinensis, Buddleja offlcinalis, Glycyrrhiza uralensis, Sanguisorba officinalis, Bupleurum chinense, Apium graveolen and Curuma zedoaria were tested. The growth curve of hepatoma cell was described, and the growth status in different periods were observed by inverted microscope. [ Result] Cells induced by active substance would be condensing, clear brim, which have significant differences from normal SMMC- 7721 cells. The results suggested that ESCG, ESCC, ESCB could inhibit proliferation of SMMC-7721 cells at the concentration of 1.0 -1.5 mg/ml, and the inhibition rate were 51.6%, 48.5%, 52.9% respectively. With the increasing of concentration, the inhibition strengthened. [ Conclusion] MTT method could be used as a basic model for screening important anti-hepatoma.

Protein profile of human hepatocarcinoma cell line SMMC-7721:Identification and functional analysis

AIM： TO investigate the protein profile of human hepatocarcinoma cell line SMMC-7721, to analyze the specific functions of abundant expressed proteins in the processes of hepatocarcinoma genesis, growth and metastasis, to identify the hepatocarcinoma-specific biomarkers for the early prediction in diagnosis, and to explore the new drug targets for liver cancer therapy. METHODS： Total proteins from human hepatocarcinoma cell line SMMC-7721 were separated by two-dimensional electrophoresis （2DE）. The silver-stained gel was analyzed by 2DE software Image Master 2D Elite. Interesting protein spots were identified by peptide mass fingerprinting based on matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry （MALDI-TOF-MS） and database searching. RESULTS： We obtained protein profile of human hepatocarcinoma cell line SMMC-7721. Among the twenty-one successfully identified proteins, mitofilin, endoplasmic reticulum protein ERp29, ubiquinol-cytochrome C reductase complex core protein I, peroxisomal enoyl CoA hydratase, peroxiredoxin-4 and probable 3-oxoacid CoA transferase 1 precursor were the six novel proteins identified in human hepatocarcinoma cells or tissues. Specific functions of the identified heat-shock proteins were analyzed in detail, and the results suggested that these proteins might promote tumorigenesis via inhibiting cell death induced by several cancer-related stresses or via inhibiting apoptosis at multiple points in the apoptotic signal pathway. Other identified chaperones and cancer-related proteins were also analyzed.CONCLUSION： Based on the protein profile of SMMC-7721 cells, functional analysis suggests that the identified chaperones and cancer-related proteins have their own pathways to contribute to the tumorigenesis, tumor growth and metastasis of liver cancer. Furthermore, proteomic analysis is indicated to be feasible in the cancer study.

High-density lipoprotein as a potential carrier for delivery of a lipophilic antitumoral drug into hepatoma cells

AIM: To investigate the possibility of recombinant highdensity lipoprotein (rHDL) being a carrier for delivering antitumoral drug to hepatoma cells. METHODS: Recombinant complex of HDL and aclacinomycin (rHDL-ACM) was prepared by cosonication of apoproteins from HDL (Apo HDL) and ACM as well as phosphatidylcholine. Characteristics of the rHDL-ACM were elucidated by electrophoretic mobility, including the size of particles, morphology and entrapment efficiency. Binding activity of rHDL-ACM to human hepatoma cells was determined by competition assay in the presence of excess native HDL. The cytotoxicity of rHDL-ACM was assessed by MTT method. RESULTS: The density range of rHDL-ACM was 1.063-1.210 g/mL, and the same as that of native HDL. The purity of all rHDL-ACM preparations was more than 92%. Encapsulated efficiencies of rHDL-ACM were more than 90%. rHDL-ACM particles were typical sphere model of lipoproteins and heterogeneous in particle size. The average diameter was 31.26±5.62 nm by measure of 110 rHDL-ACM particles in the range of diameter of lipoproteins. rHDL-ACM could bind on SMMC-7721 cells, and such binding could be competed against in the presence of excess native HDL. rHDL-ACM had same binding capacity as native HDL. The cellular uptake of rHDL-ACM by SMMC-7721 hepatoma cells was significantly higher than that of free ACM at the concentration range of 0.5-10 μg/mL (P<0.01). Cytotoxicity of rHDL-ACM to SMMC-7721 cells was significantly higher than that of free ACM at concentration range of less than 5 ug/mL (P<0.01) and IC50 of rHDL-ACM was lower than IC50 of free ACM (1.68 nmol/L vs3 nmol/L). Compared to L02 hepatocytes, a normal liver cell line, the cellular uptake of rHDL-ACM by SMMC-7721 cells was significantly higher (P<0.01) and in a dose-dependent manner at the concentration range of 0.5-10 μg/mL.Cytotoxicity of the rHDL-ACM to SMMC- 7721 cells was significantly higher than that to L02 cells at concentration range of 1-7.5μg/mL (P<0.01). IC50 for SMMC-7721 cells (1.68 nmol/L) was lower than that for L02 cells (5.68 nmol/L), showing a preferential cytotoxicity of rHDL-ACM for SMMC-7721 cells. CONCLUSION: rHDL-ACM complex keeps the basic physical and biological binding properties of native HDL and shows a preferential cytotoxicity for SMMC-7721 hepatoma to normal L02 hepatocytes, HDL is a potential carrier for delivering lipophilic antitumoral drug to hepatoma cells.

Holotransferrin Enhances Selective Anticancer Activity of Artemisinin against Human Hepatocellular Carcinoma Cells

Artemisinin, also termed qinghaosu, is extracted from the traditional Chinese medicine ar- temesia annua L. （the blue-green herb） in the early 1970s, which has been confirmed for effectively treating malaria, Additionally, emerging data prove that artemisinin exhibits anti-cancer effects against many types of cancers such as leukemia, melanoma, etc. Artemisinin becomes cytotoxic in the presence of ferrous iron. Since iron influx is high in cancer cells, artemisinin and its analogs selectively kill can- cer cells with increased intracellular iron concentrations. This study is aimed to investigate the selective inhibitory effects of artemisinin on SMMC-7721 cells in vitro and determine the effect of holotransfer- fin, which increases the concentration of ferrous iron in cancer cells, combined with artemisinin on the anticancer activity. MTT assay was used for assessing the proliferation of SMMC-7721 cells treated with artemisinin. The induction of apoptosis and inhibition of colony formation in SMMC-7721 cells treated with artemisinin were determined by TdT-mediated dUTP nick end labeling （TUNEL） and col- ony formation assay, respectively. The results showed that artemisinin at various concentrations signifi- cantly inhibited growth, colony formation and cell viability of SMMC-7721 cells （P〈0.05）, likely due to induction of apoptosis of SMMC-7721 cells. Of interest, it was found that incubation of artemisinin combined with holotransferrin sensitized the growth inhibitory effect of artemisinin on SMMC-7721 cells （P〈0.01）. Our data suggest that treatment with artemisinin leads to inhibition of viability and pro- liferation, and apoptosis of SMMC-7721 ceils. Furthermore, we observed that holotransferrin signifi- cantly enhanced the anti-cancer activity of artemisinin. This study may provide a potential therapeutic choice for liver cancer.

Docetaxel shows radiosensitization in human hepatocellular carcinoma cells

AIM: To determine the radiosensitizing potential of docetaxel in human hepatocellular carcinoma SMMC-7721 cells and its mechanisms.METHODS: SMMC-7721 cells were incubated with docetaxel at 0.125, 0.25, and 0.5 nmoL/L for 24 h and at 0.125 and 0.25 nmol/L for 48 h before irradiation. Radiation doses were given from 0 to 10 Gy. Cell survival was measured by a standard clonogenic assay after a 9-d incubation. The reactive oxygen species (ROS) and glutathione (GSH) are detected after being given the same dose of docetaxel for the same time. RESULTS: The sensitization enhancement ratios (SER) for SMMC-7721 cells determined at the 50% survival level were 1.15, 1.21 and 1.49 at 0.125, 0.25, and 0.5 nmol/L for pre-incubation of 24 h, respectively; the SER were 1.42, 1.67 at 0.125 and 0.25 nmol/L, for pre-incubation of 48 h, respectively. The ROS of SMMC-7721 cells increased and GSH decreased after pretreatment with the same doses of docetaxel for 24 or 48 h.CONCLUSION: A radiosensitizing effect of docetaxel could be demonstrated unambiguously in this cell line used. In addition, our data showed that the mechanism of radiopotentiation by docetaxel probably does not involve a G2/M block in SMMC-7721 cells, and ROS generation and GSH deletion may play a key role in the radiosensitizing effect of docetaxel.

Combined anti-tumor effects of mDRA-6 and nimesulide on human hepatocellular cancer cell line SMMC-7721

Objective: The aim of this work was to evaluate anti-tumor effects of mDRA-6 plus nimesulide on a human hepatocellular cancer cell line, SMMC-7721, and study the main mechanisms. Methods: The DR5 receptor of SMMC-7721 cells was detected by flow cytometry (FCM). For further experimental application, SMMC-7721 cells were treated with proper dose of mDRA-6, nimesulide, or mDRA-6 plus 200 μmol/L nimesulide; untreated SMMC-7721 cells were comparably set as control. Cytotoxicity was tested by MTT assay; cell morphology was examined using Hoechst 33258 staining; and apoptosis was determined by FCM. Results: The positive rate of DR5 on SMMC-7721 was 95.0%. Either mDRA-6 or nimesulide alone induces SMMC-7721 cell death in a dose-dependent manner. Treatment of 1,600 ng/mL mDRA-6 for 12h led to a cell-death rate of 35.0%, while an increased cell-death rate (91.1%) was found under the same condition of mDRA-6 treatment supple- mented with 200 μmol/L nimesulide. Hoechst 33258 and Annexin V/PI staining confirmed apoptosis as the main cause of this anti-tumor response. Conclusion: Both mDRA-6 and nimesulide can induce apoptosis of SMMC-7721 cells, and they have synergistic anti-tumor activities against SMMC-7721.

Modulating effects of survivin antisense oligonucleotide on changes of apoptosis and cell cycle of human hepatocellular carcinoma cell line SMMC-7721

To investigate the modulating effects of survivn antisense oligonucletode (ASODN) on the cell cycle and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721 and explore its mechanism.Methods Survivin ASODN was transfected into SMMC-7721 cells mediated by DOTAP liposomal reagent.Electron microscopy,flow cytometry and RT-PCR were used to detect the changes in cell ultrastructure,apoptosis,cell cycle and the expression of cyclinB1 mRNA,respectively.Results After transfection of survivin ASODN,the expression of cyclinB1 mRNA in the cells significantly increased and increase in G2-M arrest and apoptosis appeared.Meanwhile,the cell ultrastructure had apoptotic changes such as chromatin condensation and apoptotic body formation.Conclusion Survivin ASODN can induce the expression of cyclinB1 that may result in G2-M arrest.Consequently,apoptosis is triggered.Survivin ASODN transfection might be an improtant new treatment for HCC.14 refs,2 figs,1 tab.

苦参碱对SMMC-7721细胞周期及凋亡的影响

目的:研究苦参碱对肝癌细胞周期和凋亡的影响。方法:体外培养SMMC-7221细胞,采用MTT法观察不同浓度苦参碱对SMMC-7721细胞抑制情况,应用免疫组化法观察激活型Caspase-3蛋白表达,采用流式细胞术PI单染观察细胞周期。结果:苦参碱抑制SMMC-7221细胞增殖,抑制率呈浓度依赖关系,IC50为1.1 g/L,0.8 g/L和1.2 g/L苦参碱作用48 h,SMMC-7221细胞激活型Caspase-3表达增强,引起G1期阻滞。结论:苦参碱能够抑制肝癌增殖,诱导其凋亡。

脱落酸对SMMC-7721人肝癌细胞诱导分化作用的研究

目的探讨脱落酸(abscisicacid,ABA)对SMMC-7721人肝癌细胞的诱导分化作用.方法采用细胞培养方法,分别以RPMI-1640培养液、HMBA以及不同浓度ABA处理细胞,以改良MTT法检测细胞抑制率,流式细胞仪检测细胞周期,观察各组细胞的超微结构.结果除0.1μg/mLABA的浓度以外,其它浓度都能抑制细胞增殖且抑制率随时间延长和浓度的增加而增高.细胞阻滞于G0/G1期,细胞超微结构向正常方向逆转.结论ABA对SMMC-7721人肝癌细胞具有抗增殖、促分化作用.

Expression of aquaporin-1 in SMMC-7221 liver carcinoma cells promotes cell migration

Migration of tumor cells is a crucial step in tumor invasion and metastasis. Here we provide evidence that aquaporin expression is involved in tumor cell migration. RT-PCR, immunofluorescence and Western blot analysis demonstrated the AQP1 protein expression on the plasma membrane of SMMC-7221 human hepatoma cells. SMMC-7221 cell clones with high (SMMC-7221hPf) and low (SMMC-7221lPf) water permeability were identified by functional assays with corresponding high and low AQP1 expression. Cell migration rate was remarka- bly higher in SMMC-7221hPf cells than SMMC-7221l Pf cells, assessed by Boyden chamber and wound healing assays, whereas cell growth and adhesion were not different. Adenovirus-mediated AQP1 ex- pression in SMMC-7221lPf cells increased their water permeability and migration rate. These results pro- vide the first evidence that aquaporin-mediated membrane water permeability enhances tumor cell migration and may be associated with tumor invasion and metastasis.

Alreration of nuclear matrix-intermediate filament system and differential expression of nuclear matrix proteins during human hepatocarcinoma cell differentiation

AIM： To investigate the association between the configurational and compositional changes of nuclear matrix and the differentiation of carcinoma cells. METHODS： Cells cultured with or without 5 × 10^-3 mmol/L of hexamethylene bisacetamide （HMBA） on Nickel grids were treated by selective extraction and prepared for whole mount observation under electron microscopy. The samples were examined under transmission electron microscope. Nuclear matrix proteins were selectively extracted and subjected to subcellular proteomics study. The protein expression patterns were analyzed by PDQuest software. Spots of differentially expressed nuclear matrix proteins were excised and subjected to in situ digestion with trypsin. The peptides were analyzed by matrix-assisted laser- desorption/ionization time of flight mass spectrometry （MALDI-TOF-MS）. Data were submitted for database searching using Mascot tool （www.matrixscience.com）. RESULTS： The nuclear matrix （NM） and intermediate filament （IF） in SMMC-7721 hepatocarcinoma cells were found relatively sparse and arranged irregularly. The nuclear lamina was non-uniform, and two kinds of filaments were not tightly connected. After induction for differentiation by HMBA, the NM-IF filaments were concentrated and distributed uniformly. The heterogeneous population of filaments, including highly branched utrathin filaments could also be seen in the regular meshwork. The connection between the two kinds of filaments and the relatively thin, condensed and sharply demarcated lamina composed of intermediate- sized filaments was relatively fastened. Meanwhile, 21 NM proteins changed remarkably during SMMC-7721 cell differentiation. Four proteins, i.e. mutant Pystl, hypothetical protein, nucleophosminl, and LBP were downregulated, whereas four other proteins, eIF6, p44 subunit, 13-tubulin, and SIN3B were upregulated with the last one, SR2/ASF found only in the differentiated SMMC-7721 cells. CONCLUSION： The induced differentiation of SMMC-7721 cells by HMBA is accompanied by the configurational changes of nuclear matrix-intermediate filament （NM-IF） system and the compositional changes of nuclear matrix protein expression. These changes may be important morphological or functional indications of the cancer cell reversion.

健脾化瘀方对人肝癌细胞SMMC-7721增殖和凋亡的影响

[目的]探讨健脾化瘀方对人肝癌细胞系SMMC-7721的抑制率及药物浓度和作用时间对细胞抑制率的影响,以及IC_(50)药物浓度下对SMMC-7721凋亡的影响。[方法]采用MTT法,观察不同浓度的健脾化瘀方对人肝癌细胞株SMMC-7721增殖的影响及与药物作用时间之间的关系。用AnnexinV/PI双染色法,用流式细胞仪检测健脾化瘀方对肝癌细胞株SMMC-7721凋亡的影响。[结果]健脾化瘀方浓度在5mg/mL时,对SMMC-7721细胞的增殖有明显的抑制作用,呈剂量依赖和时间依赖效应关系。健脾化瘀方对人肝癌细胞SMMC-7721作用24h后,肝癌细胞凋亡率升高,并有一定的浓度依赖性。[结论]健脾化瘀方有抑制SMMC-7721细胞的增殖,能诱导人肝癌细胞株SMMC-7721的凋亡。

Differential Proteomics in Malignant and Normal Liver Cell Lines

Objective： To detect differential protein expression in malignant and normal liver cell lines in vitro using the SELDI ProteinChip platform, for investigating the pathogenesis of liver cancer. Methods： Two cell lines, human normal liver cell line L02 and hepatoma cell line SMMC-7721 were cultured routinely, harvested in good condition and lysed. After quantification, the supernatant of the lysate was tested by IMAC3 （Immobilized Mental Affinity Capture） and WCX2 （Weak Cation Exchange） chips on the SELDI-TOF-MS ProteinChip reader. Results： Protein expression differed between the malignant and normal liver cell lines. A total of 20 differentially expressed proteins were found, among which, 7 were captured by the IMAC3 chip and 14 by the WCX2 chip. Peaks at 5,419, 7,979 and 11,265 Da were higher and at 8,103, 8,492, 10,160 and 11,304 Da lower in SMMC-7721 cells by the IMAC3 chip; peaks at 7,517, 7,945 and 7,979 Da were higher and at 5,061, 5,551, 5,818, 7,439, 9,401,10,100, 10,312, 11,621, 11,662, 11,830 and 12,772 Da lower in SMMC-7721 cells by the WCX2 chip. Interestingly, both chips captured the 7,979 Da peak. In addition, the 11,081 Da peak corresponded precisely with the molecular mass of the calcium binding protein S100A10, which may participate in the formation of liver cancer in association with p36. Conclusion： Detecting differential protein expression in malignant and normal liver cell lines using the SELDI ProteinChip platform was simple, sensitive and repeatable. The results we obtained can serve as a basis for investigating the pathogenesis of liver cancer and aid the discovery of new therapeutic targets.

Mechanism Analyses for Elucidating the Role of LOXL2 Silencing in Hepatocellular Carcinoma

The paper aimed to study the effect of lysyl oxidase-like 2 （LOXL2） on hepatocellular carcinoma （HCC） and explore the biological mechanisms of tumorigenicity and progression in HCC. The authors used four HCC cell lines to identify LOXL2. A lentiviral vector containing LOXL2-siRNA was constructed to silence the LOXL2 gene in SMMC-7721 cell line, and mRNA of the target gene was detected by real-time polymerase chain reaction （RT-PCR）. The effect of LOXL2 silencing on the growth of SMMC-7721 cells was explored with flow cytometry profiling and BrdU labeling. Downstream genes of LOXL2 were selected by microarray and verified by Western Blotting. In the results, LOXL2 expression was significantly up-regulated in four types of HCC cell lines, therefore, SMMC-7721 cell line was selected for further exploration. When SMMC-7721 cell line was infected with LOXL2-siRNA, the expression of LOXL2 mRNA decreased. The silencing of LOXL2 resulted in the cell cycle arrest at the G 1-phase, the increased apoptosis and the decreased growth of SMMC-7721 cells on the indicated days by BrdU. Moreover, the MDM2, BIRC3, CDC42, FOS and TGFBR2 genes were selected and verified to be the downstream genes of LOXL2. In conclusion, LOXL2 contributes to the genesis and progression of HCC cells and works by regulating downstream genes of LOXL2 in certain pathways. Therefore, LOXL2 may play an important role in the progression and prognosis of HCC.

PI3K/AKT信号转导通路在肝癌细胞生长和黏附中的作用

目的:探讨PI3K/AKT(磷脂酰肌醇-3-激酶/蛋白激酶B)信号转导通路在人肝癌细胞株SMMC-7221生长和黏附中的作用机制.方法:应用LY294002作用于SMMC-7221细胞,并设对照组和实验组(LY294002:5、10、20、40μmol/L),MTT法检测LY294002作用24、48、72、96h后,对SMMC-7221细胞增殖的影响;采用肿瘤细胞-基质黏附实验检测对照组和干预组SMMC-7221黏附能力的变化;流式细胞仪检测肝癌细胞黏附分子CD44s表达情况;细胞免疫化学S-P法检测SMMC-7221细胞血管内皮生长因子(vascular endothelial growth factor,VEGF)和CD44V6蛋白表达.结果:LY294002对SMMC-7221细胞的增殖有抑制作用,呈剂量和时间依赖性;5、10mol/L的LY294002作用于肝癌细胞后与对照组相比CD44s,VEGF,CD44V6蛋白表达下降(CD44s:42.84%±6.35%,20.21%±4.5%vs89.23%±3.91%,P<0.01;VEGF:103.11±18.60,68.99±15.99vs137.84±22.50,P<0.01;CD44V6:47.33±6.15,33.09±5.23vs61.36±7.39,P<0.01);5、10μmol/L的LY294002干预后与对照组相比SMMC-7221黏附能力下降(0.498±0.024,0.407±0.029vs0.616±0.080,P<0.01).结论:阻断PI3K/AKT信号传导通路,肝癌细胞生长受到抑制、黏附能力下降.LY294002抑制肝癌细胞黏附力的作用机制与通过降低CD44V6、CD44s和VEGF水平有关.