Berberine induces cell death in human hepatoma cells in vitro by downregulating CD147

The isoquinoline plant alkaloid berberine has anti-tumor effects on a variety of carcinoma cells, mainly through inhibition of cell proliferation, apoptosis induction and cell cycle arrest. However, the mechanisms underlying its role in tumor progression are unknown. In the present study, we investigated the molecular mechanisms involved in berberine-induced cell death in human hepatoma carcinoma cell (HCC) lines HepG2 and SMMC7721. Our results showed that berberine inhibited tumor cell viability in a dose- and time-dependent manner, and induced cell death via apoptosis and autophagy. Moreover, berberine treatment significantly inhibited CD147 expression by HCC cells in a dose-dependent manner. Overexpression of CD147 protein markedly reduced berberine-induced cell death. Our data provide the first experimental evidence that berberine induces cell death in HCC cells via downregulation of CD147 and suggest a new mechanism to explain its anti-tumor effects.     

Downregulation of CD147 expression alters cytoskeleton architecture and inhibits gelatinase production and SAPK pathway in human hepatocellular carcinoma cells

Background

CD147 plays a critical role in the invasive and metastatic activity of hepatocellular carcinoma (HCC) cells by stimulating the surrounding fibroblasts to express matrix metalloproteinases (MMPs). Tumor cells adhesion to extracellular matrix (ECM) proteins is the first step to the tumor metastasis. MMPs degrade the ECM to promote tumor metastasis. The aim of this study is to investigate the effects of small interfering RNA (siRNA) against CD147 (si-CD147) on hepatocellular carcinoma cells' (SMMC-7721) architecture and functions.

Methods

Flow cytometry and western blot assays were employed to detect the transfection efficiency of si-CD147. Confocal microscopy was used to determine the effects of si-CD147 on SMMC-7721 cells' cytoskeleton. Invasion assay, gelatin zymography and cell adhesion assay were employed to investigate the effects of si-CD147 on SMMC-7721 cells' invasion, gelatinase production and cell adhesive abilities. Western blot assay was utilized to detect the effects of si-CD147 on focal adhesion kinase (FAK), vinculiln and mitogen-activated protein kinase (MAPK) expression in SMMC-7721 cells.

Results

Downregulation of CD147 gene induced the alteration of SMMC-7721 cell cytoskeleton including actin, microtubule and vimentin filaments, and inhibited gelatinase production and expression, cells invasion, FAK and vinculin expression. si-CD147 also blocked SMMC-7721 cells adhesion to collagen IV and phosphorylation level of SAPK/JNKs. SAPK/JNKs inhibitor SP600125 inhibited gelatinase production and expression.

Conclusion

CD147 is required for normal tumor cell architecture and cell invasion. Downregulation of CD147 affects HCC cell structure and function. Moreover, the alteration of cell behavior may be related to SAPK/JNK Pathway. siRNA against CD147 may be a possible new approach for HCC gene therapy.     

鱼藤素对肝癌细胞株SMMC-7721增殖抑制和凋亡诱导作用的研究

目的 研究鱼藤素对肝癌细胞株SMMC-7721增殖和凋亡的影响及其作用机制.方法 MTT法检测鱼藤素对SMMC-7721细胞增殖的抑制作用;DNA琼脂糖凝胶电泳观测细胞凋亡情况;采用Western blotting法检测相关蛋白表达水平的变化,探讨其作用机制.结果 鱼藤素呈剂量和时间依赖性抑制SMMC-7721细胞增殖,诱导细胞凋亡致DNA ladder形成,出现相应的形态学改变;鱼藤素可明显降低Akt的磷酸化水平.结论 鱼藤素可通过下调Akt的活性,抑制SMMC-7721的增殖并诱导细胞凋亡,或可成为一种新的抗肝癌药物.     

TSA对人肝癌细胞SMMC-7721的抑制作用及其机制

目的:研究去乙酰化转移酶抑制剂TSA对肝癌细胞SMMC-7721的作用及其机理。方法:利用细胞计数,流式细胞仪分析细胞凋亡及细胞周期,Tunel试验研究TSA对肝癌细胞SMMC-7721的作用;利用western研究TSA对肝癌细胞蛋白表达的影响。结果:TSA可明显抑制肝癌细胞SMMC-7721的生长,并可诱导细胞凋亡。可阻滞肝癌细胞SMMC-7721细胞周期于G0/G1期。可增加p53,p21,bax等基因的表达,降低BCL-2的表达。结论:去乙酰化转移酶抑制剂TSA可明显抑制肝癌细胞SMMC-7721的生长并诱导其凋亡,其主要通过调控一些肿瘤相关基因的表达起作用。     

水飞蓟宾对人肝癌细胞SMMC-7721体外增殖的影响

目的:探讨水飞蓟宾对SMMC-7721细胞的抗增殖作用。方法:MTT法观察对细胞的抑制作用;免疫细胞化学法检测增殖细胞核抗原(PCNA)及Ki-67的表达;流式细胞仪分析细胞周期及凋亡;光镜及透射电镜观察细胞形态学的变化。结果:水飞蓟宾可抑制SMMC-7721的增殖,并降低PCNA、Ki-67的表达及引起细胞G2/M期阻滞,同时诱导凋亡。光镜发现细胞体积缩小,核固缩深染;电镜可见凋亡及凋亡小体。结论:在体外,水飞蓟宾可抑制SMMC-7721细胞的增殖。     

HAb18G/CD147 inhibits starvation-induced autophagy in human hepatoma cell SMMC7721 with an involvement of Beclin 1 down-regulation

HAb18G/CD147, a transmembrane glycoprotein highly expressed in various types of malignant cells, mainly functions as an inducer of matrix metalloproteinases to promote tumor growth, invasion and metastasis. However, whether there are other mechanisms underlying the role of HAb18G/CD147 in tumor progression remains to be elucidated. In this study, we investigated the functional effects of HAb18G/CD147 on autophagy in hepatoma cell line SMMC7721 using immunofluoscence staining, Western blot and transmission electronmicroscopy. Our data showed that specific small interference RNA (siRNA) considerably down-regulated the expression of HAb18G/CD147 in SMMC7721 cells at both messenger RNA (mRNA) and protein levels. The down-regulation of HAb18G/CD147 significantly promoted starvation-induced autophagy in a dose-dependent manner. Using trypan blue exclusion assay, we found that HAb18G/CD147 notably enhanced the survival of SMMC7721 cells through inhibiting starvation-induced autophagy. In addition, we demonstrated that HAb18G/CD147 down-regulated the expression of autophagy-regulating protein Beclin 1 in SMMC7721 cells. Furthermore, our data indicated that HAb18G siRNA-transfected SMMC7721 cells had a significantly decreased level of phosphorylated serine/threonine protein kinase B (pAkt) and the expression of Beclin 1 was inversely associated with the level of pAkt, suggesting that the Class I phosphatidylinositol 3 kinase-Akt pathway may be involved in the down-regulation of Beclin 1 by HAb18G/CD147. Overall, we provide the first experimental evidence to show that HAb18G/CD147 may play an important role in the inhibitory regulation of autophagy. Therefore, our data suggest a new molecular mechanism for HAb18G-mediated hepatoma progression. ( Cancer Sci 2009; 100: 837–843)     

Icariin,a natural flavonol glycoside,induces apoptosis in human hepatoma SMMC-7721 cells via a ROS/JNK-dependent mitochondrial pathway

In this study, the anticancer effect of icariin, a natural flavonol glycoside, against human hepatoma SMMC-7721 cells and the underlying mechanisms were investigated. Icariin triggered the mitochondrial/caspase apoptotic pathway indicated by enhanced Bax-to-Bcl-2 ratio, loss of mitochondrial membrane potential, cytochrome c release, and caspase cascade. Moreover, icariin induced a sustained activation of the phosphorylation of c-Jun N-terminal kinase (JNK) but not p38 and ERK1/2, and SP600125 (an inhibitor of JNK) almost reversed icariin-induced apoptosis in SMMC-7721 cells. In addition, icariin provoked the generation of reactive oxygen species (ROS) in SMMC-7721 cells, while the antioxidant N-acetyl cysteine almost completely blocked icariin-induced JNK activation and apoptosis. Taken together, these findings suggest that icariin induces apoptosis through a ROS/JNK-dependent mitochondrial pathway.     

三氧化二砷和胂酸基乙酸体外抗癌作用的比较

背景与目的:近来,有研究表明某些有机砷诱导细胞凋亡的能力强于无机砷,胂酸基乙酸(arsacetyl,ASAC)为有机砷的一种。本研究比较三氧化二砷(As2O3)和ASAC对肝癌细胞的抑制作用及诱导凋亡作用。方法:采用MTT(methythiazolyltetrazolium)法和细胞凋亡检测法观察As2O3和ASAC对SMMC-7721细胞增殖的影响及作用机制;用MTT法检测药物对正常血管内皮细胞(VEC)毒副作用。结果:As2O3和ASAC都明显抑制细胞增殖,抑制作用呈时间和浓度依赖性,且ASAC的抑制作用明显强于As2O3。如药物作用48h,0.1μmol/LAs2O3组抑制率为(14.2±1.5)%,0.1μmol/LASAC组为(27.1±3.0)%。1μmol/LAs2O3和0.1μmol/LASAC对VEC几乎无毒副作用,同样条件下作用于SMMC-7721细胞株,有凋亡小体生成,凝胶电泳出现DNA梯度图谱,流式细胞检查见明显的凋亡峰出现,并使细胞周期阻滞在S+G2/M期。结论:As2O3和ASAC都可以在体外诱导肝癌细胞凋亡,且ASAC诱导凋亡的能力强于As2O3,两者都作用于G0/G1期细胞。     

mDRA-6与尼美舒利对人肝癌细胞系SMMC-7721细胞的协同杀伤效应

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.     

Akt inhibitor shows anticancer and radiosensitizing effects in malignant glioma cells by inducing autophagy

Autophagy, or programmed cell death type II, is one of the responses of cancer cells to various therapies, including ionizing radiation. Recently, we have shown that radiation induces autophagy, but not apoptosis, in various malignant glioma cell lines. Autophagy is mainly regulated by the mammalian target of rapamycin (mTOR) pathway. The Akt/mTOR pathway also mediates oncogenesis and radioresistance. Thus, we hypothesized that inhibiting this pathway has both an anticancer and radiosensitizing effect by activating autophagy. The purpose of our study was therefore to determine whether and by which mechanisms an Akt inhibitor, 1L-6-hydroxymethyl-chiro-inositol 2(R)-2-O-methyl-3-O-octadecylcarbonate, had anticancer and radiosensitizing effects on malignant glioma U87-MG and radioresistant U87-MG cells with a consistitutively active form of epidermal growth factor receptor (U87-MGDeltaEGFR). Treatment with the Akt inhibitor successfully inhibited Akt activity and reduced cell viability in both cell lines. In terms of the mechanism, the Akt inhibitor decreased phosphorylated p70S6 kinase, a downstream target of Akt, and induced autophagy, but not apoptosis. Furthermore, the Akt inhibitor radiosensitized both U87-MG and U87-MGDeltaEGFR cells by enhancing autophagy. Specific inhibition of Akt using the dominant-negative Akt plasmid also resulted in enhanced radiation-induced autophagy. In conclusion, an Akt inhibitor showed anticancer and radiosensitizing effect on U87-MG and U87-MGDeltaEGFR cells by inducing autophagy. Thus, Akt inhibitors may represent a promising new therapy as a single treatment or used in combination with radiation for malignant gliomas, including radioresistant ones that express DeltaEGFR.     

Geraniol induces cooperative interaction of apoptosis and autophagy to elicit cell death in PC-3 prostate cancer cells

Geraniol, an acyclic dietary monoterpene, suppresses prostate cancer growth and enhances docetaxel chemosensitivity in cultured cell or xenograft tumor models. However, the mechanisms of the geraniol action against prostate cancer are largely unknown. In this study, we investigated the cellular and molecular mechanisms of geraniol-induced cell death in PC-3 prostate cancer cells. Among the examined structurally and functionally similar monoterpenes, geraniol potently induced apoptosis and autophagy. Although independent processes, apoptosis and autophagy acted as cooperative partners to elicit geraniol-induced cell death in PC-3 cells. At a molecular level, geraniol inhibited AKT signaling and activated AMPK signaling, resulting in mTOR inhibition. Combined treatment of AKT inhibitor and AMPK activator markedly suppressed cell growth compared to either treatment alone. Our findings provide insight into future investigations that are aimed at elucidating the role of apoptosis and autophagy in prostate cancer therapy and at developing anticancer strategies co-targeting AKT and AMPK.     

mDRA-6与尼美舒利对人肝癌细胞系SMMC-7721细胞的协同杀伤效应

背景与目的:mDRA-6为本实验室制备的具有肿瘤细胞杀伤作用的抗人死亡受体5(death receptor5,DR5)的单克隆抗体,尼美舒利作为特异性环氧合酶-2(cyclooxygenase-2,COX-2)抑制剂,近年来发现其对某些肿瘤细胞系的细胞具有促凋亡作用,本研究探讨mDRA-6与尼美舒利对肝癌细胞系SMMC-7721的杀伤作用,及二者有无协同效应。方法:流式细胞术检测细胞表面DR5的表达率;分别用一定浓度的mDRA-6、尼美舒利、mDRA-6联合200μmol/L尼美舒利处理SMMC-7721细胞,MTT法检测细胞毒性作用,Hoechst33258染色观察SMMC-7721细胞核形态变化,流式细胞术定量分析凋亡细胞率。结果:SMMC-7721细胞表面DR5的表达率为95.0%,mDRA-6能够诱导SMMC-7721细胞凋亡,存在浓度依赖性(r=0.984,P=0.002),25ng/mL作用12h可杀伤10.5%的细胞,1600ng/mL作用12h可杀伤35.0%的细胞。尼美舒利能够诱导SMMC-7721细胞凋亡,200μmol/L作用12h可使5.0%的细胞凋亡,800μmol/L作用12h可杀伤34.0%的细胞,存在浓度依赖性(r=0.929,P=0.002)。尼美舒利与mDRA-6联合对SMMC-7721细胞具有协同杀伤作用(q=1.23),200μmol/L的尼美舒利协同25ng/mL与1600ng/mL的mDRA-6作用12h可分别杀伤31.2%与91.1%的SMMC-7721细胞,Hoechst33258染色和Annexin V/PI染色证实杀伤作用是通过诱导细胞凋亡实现的。结论:mDRA-6与尼美舒利均有杀伤SMMC-7721细胞的作用,二者具有协同作用,该作用是通过诱导凋亡实现的。     

Curcumin induces apoptosis involving bax/bcl-2 in human hepatoma SMMC-7721 cells

Curcumin is a major active component of Curcuma aromatica salisb, which has been shown to inhibit proliferation of a wide variety of tumor cells. In this study, the molecular mechanisms of curcumin inducing apoptosis in human hepatoma SMMC-7721 cells were examined. We find that curcumin inhibits the growth of SMMC-7721 cells significantly in a concentration-depenent manner, with typical apoptotic morphological changes of cellular nuclei. Annexin-V/PI double staining detected by flow cytometry and expression of the relative apoptotic proteins (Bax, Bcl-2 and caspase-3) revealed a strong apoptosis-inducing competent of curcumin in SMMC-7721 cells. Curcumin increased the expression of bax protein while decreasing that of bc1-2 protein significantly. The results suggest that curcumin induction of apoptosis involves modulation of bax/bcl-2 in SMMC-7721 cells and provide a molecular basis for the development of naturally compounds as novel anticancer agents for human hepatomas.     

塞来昔布抑制肝癌细胞株增殖及其机制的实验研究

目的:研究特异性环氧化酶-2(COX-2)抑制剂塞来昔布对人肝癌细胞株SMMC-7721是否有抑制增殖、诱导凋亡作用并初步探讨其作用机制。方法:采用四氮唑盐比色法(MTT法)观察不同浓度的塞来昔布作用后细胞增殖活力改变;流式细胞仪检测细胞凋亡百分率及细胞周期变化;免疫组化观察Bcl-2蛋白和Bax蛋白表达情况。结果:MTT法显示随着塞来昔布浓度和作用时间增加,细胞增殖抑制率上升;流式细胞仪测定空白对照组未见明显凋亡峰,塞来昔布组出现凋亡峰,凋亡率随着时间及药物浓度变化而变化,二者呈正相关;免疫组化显示经塞来昔布干预后,凋亡蛋白Bax表达增加,而Bcl-2表达减少,并随时间和药物浓度变化而明显。结论:塞来昔布抑制SMMC-7721细胞增殖,促进SMMC-7721细胞凋亡,并呈剂量和时间依赖性。其作用机制之一可能是通过减少Bcl-2的表达,增加Bax的表达,从而启动细胞凋亡途径。     

Resveratrol induces apoptosis via ROS-triggered autophagy in human colon cancer cells

Resveratrol (Res; 3,4',5-trihydroxy-trans-stilbene), which is a polyphenol found in grapes, can block cell proliferation and induce growth arrest and/or cell death in several types of cancer cells. However, the precise mechanisms by which Res exerts anticancer effects remain poorly understood. Res blocked both anchorage-dependent and -independent growth of HT-29 and COLO 201 human colon cancer cells in a dose- and time-dependent manner. Annexin V staining and Western blot analysis revealed that Res induced apoptosis accompanied by an increase in Caspase-8 and Caspase-3 cleavage. In HT-29 cells, Res caused autophagy as characterized by the appearance of autophagic vacuoles by electron microscopy and elevation of microtubule-associated protein 1 light chain 3 (LC3)-II by immunoblotting, which was associated with the punctuate pattern of LC3 detected by fluorescein microscopy. Inhibition of Res-induced autophagy by the autophagy inhibitor 3-methyladenine caused a significant decrease in apoptosis accompanied by decreased cleavage of Casapse-8 and Caspase-3, indicating that Res-induced autophagy was cytotoxic. However, inhibition of Res-induced apoptosis by the pan-caspase inhibitor Z-VAD(OMe)-FMK did not decrease autophagy but elevated LC3-II levels. Interestingly, Res increased the intracellular reactive oxygen species (ROS) level, which correlated to the induction of Casapse-8 and Caspase-3 cleavage and the elevation of LC3-II; treatment with ROS scavenger N-acetyl cysteine diminished this effect. Therefore, the effect of Res on the induction of apoptosis via autophagy is mediated through ROS in human colon cancer cells.     

23,24-Dihydrocucurbitacin B induces G2/M cell-cycle arrest and mitochondria-dependent apoptosis in human breast cancer cells (Bcap37)

23,24-Dihydrocucurbitacin B (DHCB), a cucurbitacin-derived compound known to posses anticancer and anti-inflammatory activities. In this study, DHCB, isolated from roots of Trichosanthes kirilowli which is a traditional Chinese herb medicine used as treatments for cancer and other diseases, has been found to inhibit the proliferation of human cancer cell lines Bcap37, HeLa, SW620, SMMC-7721, K562 and MCF-7 in a dose- and time-dependent manner, and induce apoptosis in human breast cancer cell line Bcap37 at low concentration. DHCB-induced Bcap37 apoptosis was characterized with the changes in nuclear morphology, DNA fragmentation, activation of caspase-like activities, poly(ADP-ribose) polymerase cleavage, release of cytochrome c into cytosol. The cell death was partly prevented by a caspase-family inhibitor Z-VAD-FMK. The results suggest that DHCB-induced Bcap37 apoptosis through mitochondrial dependent pathway. Flow cytometric analysis revealed that at the lower dose of 1.8 and 3.6muM, DHCB-induced cancer cell lines death via an apoptotic process rather than necrotic one; whereas, the higher dose of 8.9, 17.9 and 35.7muM induced cell death via the necrotic process. Cell-cycle analysis demonstrated DHCB induction of G(2)/M phase cell-cycle arrest and apoptosis. The overall results suggest that DHCB might have the therapeutic value against human cancer cell lines, especially the breast cancer cell lines.     

沙利度胺对人肝癌细胞株SMMC-7721体外生长的抑制作用

目的 研究沙利度胺对人肝癌细胞株SMMC-7721体外生长的抑制作用及其可能的机制.方法 将不同浓度的沙利度胺作用于人肝癌细胞株SMMC-7721,采用四甲摹偶氮唑蓝(MTT)法检测沙利度胺对SMMC-7721细胞的增殖抑制作用.将SMMC-7721细胞培养至对数生长期,采用DNA琼脂糖凝胶电泳、荧光显微镜观察、流式细胞仪检测等方法 观察沙利度胺处理后SMMC-7721细胞的凋亡梯度、形态学变化和凋亡率,并对凋亡调控蛋白caspase-3的表达进行测定.采用酶联免疫吸附(ELISA)法测定不同浓度的沙利度胺处理后SMMC-7721细胞表达血管内皮生长因子(VEGF)的变化.结果 沙利度胺的浓度从3.125μg/ml增至200μg/ml时,其对SMMC-7721细胞的增殖抑制率从11.7%增至34.2%;当沙利度胺的浓度>25 μg/ml时,其对SMMC-7721细胞的增殖抑制作用明显强于空白对照组(P<0.05).200 μg/ml的沙利度胺处理SMMC-7721细胞24 h后,行琼脂糖凝胶电泳,可见到DNA梯形条带;48 h后梯形条带更明显,并且在荧光显微镜下可见SMMC-7721细胞出现核固缩和核裂解现象.200μg/ml的沙利度胺处理SMMC-7721细胞12、24、48和72 h时,碘化丙啶(PI)法检测SMMC-7721细胞的凋亡率分别为3.1%±0.5%、8.4%±1.3%、19.4%±3.5%和25.8%±2.1%,24 h起的凋亡率均明显高于空白对照组SMMC-7721细胞48 h的自然凋亡率(1.6%±0.6%,均P<0.05).50、100和200μg/ml的沙利度胺处理SMMC-7721细胞48 h时,Annexin V-FITC/PI双标法检测SMMC-7721细胞的凋亡率分别为8.7%±1.2%、16.8%±2.5%和25.4%±4.5%,均明显高于空白对照组SMMC-7721细胞48 h的自然凋亡率(2.1%±0.5%,均P<0.05).随着沙利度胺浓度的增加,表达caspase-3蛋白的SMMC-7721细胞数量不断增加,而SMMC-7721细胞中VEGF的含量却逐渐下降.结论 沙利度胺可能通过诱导肝癌细胞的凋亡、抑制肿瘤血管的生成而发挥双重抗肿瘤生长的作用.     

Ａｄ-ＩＮＧ４抑制裸鼠人肝癌移植瘤生长的体内实验研究

目的　研究携带ＩＮＧ４基因的重组腺病毒（Ａｄ-ＩＮＧ４）对人肝癌细胞株ＳＭＭＣ-７７２１移植瘤生长的抑制作用及其潜在的分子机制。方法　将扩增的Ａｄ-ＩＮＧ４感染ＳＭＭＣ-７７２１细胞,Ｗｅｓｔｅｒｎｂｌｏｔ法检测Ａｄ-ＩＮＧ４在ＳＭＭＣ-７７２１细胞中的转录。用ＳＭＭＣ-７７２１细胞建立裸鼠人肝癌移植瘤模型,予Ａｄ-ＩＮＧ４（１×１０^９ｐｆｕ／ｍｌ）５０μｌ对移植瘤瘤体注射治疗,观察肿瘤生长变化;３周后处死裸鼠,摘除瘤体,称瘤重;免疫组化法检测ｐ２１、ＣＯＸ-２、Ｆａｓ、Ｂｃｌ-２、Ｂａx、Ｃａｓｐａｓｅ-３、ＶＥＧＦ、ＣＤ３４等因子的表达。结果　Ａｄ-ＩＮＧ４在ＳＭＭＣ-７７２１细胞中成功表达;Ａｄ-ＩＮＧ４对裸鼠人肝癌移植瘤有明显的生长抑制作用,Ａｄ-ＩＮＧ４组瘤体显著减小（Ｐ＜０.０１）,抑瘤率达４１.６４％;免疫组化检测显示,Ａｄ-ＩＮＧ４抑癌的分子机制可能与上调ｐ２１、Ｆａｓ、Ｂａｘ和Ｃａｓｐａｓｅ-３的表达及下调ＣＯＸ-２、Ｂｃｌ-２、ＶＥＧＦ和ＣＤ３４的表达有关。结论　Ａｄ-ＩＮＧ４能有效抑制ＳＭＭＣ-７７２１裸鼠人肝癌移植瘤的生长,其机制可能通过抑制肿瘤细胞生长、血管形成和激活细胞凋亡等多个途径共同发挥抑癌效应。     

Iso-suillin Isolated from Suillus luteus,Induces G1 Phase Arrest and Apoptosis in Human Hepatoma SMMC-7721 Cells

Iso-suillin, a natural product isolated from Suillus luteus, has been shown to inhibit the growth of somecancer cell lines. However, the molecular mechanisms of action of this compound are poorly understood. Thepurpose of this study was to investigate how iso-suillin inhibits proliferation and induces apoptosis in a humanhepatoma cell line (SMMC-7721). We demonstrated the effects of iso-suillin on cell proliferation and apoptosisin SMMC-7721 cells, with no apparent toxicity in normal human lymphocytes, using colony formation assaysand 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis. Western blotting was usedto examine the expression of G1 phase-regulated and apoptosis-associated protein levels in iso-suillin treatedSMMC-7721 cells. The results indicated that iso-suillin significantly decreased viability, induced G1 phase arrestand triggered apoptosis in SMMC-7721cells. Taken together, these results suggest the potential of iso-suillin asa candidate for liver cancer treatment.