HLE Cells Research Articles

SiRNA Targeting mTOR Effectively Prevents the Proliferation and Migration of Human Lens Epithelial Cells.

Posterior capsule opacification (PCO) is the most common complication that causes visual decrease after extracapsular cataract surgery. The primary cause of PCO formation is the proliferation of the residual lens epithelial cells (LECs). The mammalian target of rapamycin (mTOR) plays an important role in the growth and migration of LECs. In the current study, we used small interfering RNA (siRNA) to specifically attenuate mTOR in human lens epithelial B3 cells (HLE B3). We aimed to examine the effect of mTOR-siRNA on the proliferation, migration and epithelial-to-mesenchymal transition (EMT) of HLE B3 cells and explore the underlying mechanisms. The mTOR-siRNA was transfected into HLE B3 cells using lipofectamine 2000. The mRNA and protein levels of mTOR were examined to confirm the efficiency of mTOR-siRNA. The levels of mRNA and protein as well as the activity of mTOR down-stream effectors p70 ribosomal protein S6 kinase (p70S6K) and protein kinase B (PKB, AKT) were examined using real-time PCR or Western blot, respectively. The cell proliferation was determined using cell counting kit (CCK) 8 and cell growth curve assay. The cell migration was examined using Transwell system and Scratch assay. MTOR-siRNA effectively eliminated mTOR mRNA and protein. The proliferation and migration were significantly suppressed by mTOR-siRNA transfection. mTOR-siRNA reduced the mRNA of p70S6K and AKT in a time-dependent manner. Furthermore, the phosphorylation of p70S6K and AKT was decreased by mTOR-siRNA. MTOR-siRNA also eliminated the formation of mTORC1 and mTORC2 protein complex and blocked the transforming growth factor (TGF)-β-induced EMT. Our results suggested that mTOR-siRNA could effectively inhibit the proliferation, migration and EMT of HLE B3 cells through the inhibition of p70S6K and AKT. These results indicated that mTOR-siRNA might be an effective agent inhibiting HLE cells growth and EMT following cataract surgery and provide an alternative therapy for preventing PCO.

Alpha fetoprotein antagonises benzyl isothiocyanate inhibition of the malignant behaviors of hepatocellular carcinoma cells.

Benzyl isothiocyanate (BITC) is a dietary isothiocyanate derived from cruciferous vegetables. Recent studies showed that BITC inhibited the growth of many cancer cells, including hepatocellular carcinoma (HCC) cells. Alpha-fetoprotein (AFP) is a important molecule for promoting progression of HCC, in the present investigation, we explore the influence of AFP on the role of BITC in the malignant behaviours of HCC cells, and the potential underlying mechanisms. We found thatBITC inhibited viability, migration, invasion and induced apoptosis of human liver cancer cell lines, Bel 7402(AFP producer) and HLE(non-AFP producer) cells in vitro. The role of BITC involve in promoting actived-caspase-3 and PARP-1 expression, and enhancing caspase-3 activity but decreasing MMP-2/9, survivin and CXCR4 expression. AFP antagonized the effect of BITC. This study suggests that BITC induced significant reductions in the viability of HCC cell lines. BITC may activate caspase-3 signal and inhibit the expression of growth- and metastasis-related proteins; AFP is an pivotal molecule for the HCC chemo-resistance of BITC.

PIN1 in hepatocellular carcinoma is associated with TP53 gene status.

Phosphorylation of proteins on serine/threonine residues that precede proline (pSer/Thr-Pro) is specifically catalyzed by the peptidyl-prolyl cis-trans isomerase PIN1. PIN1-mediated prolyl-isomerization induces cell cycle arrest and growth inhibition through the regulation of target proteins, including TP53. We examined whether PIN1 acts in a different manner according to TP53 gene status in hepatocellular carcinoma (HCC). We investigated the expression of PIN1 and TP53 proteins in 119HCC tissue samples. We also analyzed PIN1 expression in combination with TP53 gene mutation and its correlation with the clinical outcome. In addition, we used synthetic small interfering RNA to silence PIN1 gene expression in TP53 wild-type and TP53 mutant HCC cell lines, and then evaluated cell proliferation, migration and invasion. Expression of PIN1 was strongly associated with expression of TP53 protein or TP53 mutation of HCC samples. PIN1 and TP53 expression in TP53 mutant HCC cell lines was higher than that in TP53 wild-type HCC cell lines. Silencing of PIN1 in HLE cells containing mutant TP53 significantly decreased cell proliferation, migration and invasion. In contrast to PIN1 silencing in HLE cells, PIN1 silencing in HepG2 cells containing functional wild-type TP53 resulted in enhanced tumor cell proliferation. HCC patients bearing PIN1 expression with wild-type TP53 were predicted to demonstrate favorable relapse-free survival. Our results suggest that PIN1 plays a role in cancer cell proliferation, migration and invasion in a different manner according to the TP53 gene mutation status in HCC. In particular, interaction of PIN1 with mutant TP53 can act as a tumor promoter and increase its oncogenic activities in HCC.

Alpha fetoprotein antagonizes apoptosis induced by paclitaxel in hepatoma cells in vitro.

Hepatocellular carcinoma (HCC) cell resistance to the effects of paclitaxel has not been adequately addressed. In this study, we found that paclitaxel significantly inhibited the viability of HLE, Bel 7402 and L-02 cells in a dose- and time-dependent manner. HLE cells and L-02 cells resisted the cytotoxicity of paclitaxel when transfected with pcDNA3.1-afp vectors. However, Bel 7402 cell sensitivity to paclitaxel was increased when transfected with alpha fetoprotein (AFP)-siRNA. Bel 7402 cell resistance to paclitaxel was associated with the expression of the “stemness” markers CD44 and CD133. Paclitaxel significantly inhibited growth and promoted apoptosis in HLE cells and L-02 cells by inducing fragmentation of caspase-3 and inhibiting the expression of Ras and Survivin, but pcDNA3.1-afp vectors prevented these effects. However, paclitaxel could not significantly promote the cleavage of caspase-3 or suppress the expression of Ras and Survivin in Bel 7402 cells. Silenced expression of AFP may be synergistic with paclitaxel to restrain proliferation and induce apoptosis, enhance cleavage of caspase-3, and suppress the expression of Ras and Survivin. Taken together, AFP may be an important molecule acting against paclitaxel-inhibited proliferation and induced apoptosis in HCC cells via repressing the activity of caspase-3 and stimulating the expression of Ras and Survivin. Targeted inhibition of AFP expression after treatment with paclitaxel is an available strategy for the therapy of patients with HCC.

Des-gamma-carboxy prothrombin antagonizes the effects of Sorafenib on human hepatocellular carcinoma through activation of the Raf/MEK/ERK and PI3K/Akt/mTOR signaling pathways.

Despite significant progress, advanced hepatocellular carcinoma (HCC) remains an incurable disease, and the overall efficacy of targeted therapy by Sorafenib remains moderate. We hypothesized that DCP (des-gamma-carboxy prothrombin), a prothrombin precursor produced in HCC, might be one of the reasons linked to the low efficacy of Sorafenib. We evaluated the efficacy of Sorafenib in HLE and SK-Hep cells, both of which are known DCP-negative HCC cell lines. In the absence of DCP, Sorafenib effectively inhibited the growth of HCC and induced cancer cell apoptosis. In the presence of DCP, HCC was resistant to Sorafenib-induced inhibition and apoptosis, as determined by in vitro assays and in mice xenografted with HLE cells. Molecular analysis of HLE xenografted-nude mice showed that DCP activates the transduction of the Ras/Raf/MEK/ERK and Ras/PI3K/Akt/mTOR cascades. DCP might stimulate the formation of compensatory feedback loops in the intricately connected signaling pathways when kinases are targeted by Sorafenib. Our results indicate that DCP antagonizes the inhibitory effects of Sorafenib on HCC through activation of the Ras/Raf/MEK/ERK and Ras/PI3K/Akt/mTOR signaling pathways. Taken together, our findings define a DCP-mediated mechanism of inhibition of Sorafenib in HCC, which is critical for targeting therapy in advanced HCC.

Iron depletion enhances the effect of sorafenib in hepatocarcinoma

ABSTACTHuman hepatocellular carcinoma (HCC) is known to have a poor prognosis. Sorafenib, a molecular targeted drug, is most commonly used for HCC treatment. However, its effect on HCC is limited in clinical use and therefore new strategies regarding sorafenib treatment are required. Iron overload is known to be associated with progression of chronic hepatitis and increased risk of HCC. We previously reported that iron depletion inhibited cancer cell proliferation and conversely induced angiogenesis. Indeed iron depletion therapy including iron chelator needs to be combined with anti-angiogenic drug for its anti-cancer effect. Since sorafenib has an anti-angiogenic effect by its inhibitory targeting VEGFR, we hypothesized that sorafenib could complement the anti-cancer effect of iron depletion. We retrospectively analyzed the relationship between the efficacy of sorafenib and serum iron-related markers in clinical HCC patients. In clinical cases, overall survival was prolonged in total iron binding capacity (TIBC) high- and ferritin low-patients. This result suggested that the low iron-pooled patients, who could have a potential of more angiogenic properties in/around HCC tumors, could be adequate for sorafenib treatment. We determined the effect of sorafenib (Nexavar®) and/or deferasirox (EXJADE®) on cancer cell viability, and on cell signaling of human hepatocarcinoma HepG2 and HLE cells. Both iron depletion by deferasirox and sorafenib revealed insufficient cytotoxic effect by each monotherapy, however, on the basis of increased angiogenesis by iron depletion, the addition of deferasirox enhanced anti-proliferative effect of sorafenib. Deferasirox was confirmed to increase vascular endothelial growth factor (VEGF) secretion into cellular supernatants by ELISA analysis. In in vivo study sorafenib combined with deferasirox also enhanced sorafenib-induced apoptosis. These results suggested that sorafenib combined with deferasirox could be a novel combination chemotherapy for HCC.

TAK1 promotes epithelial-mesenchymal transition of lens epithelial cells

Transforming growth factor-β-activated kinase-1 (TAK1) is thought to play a key role in the initiation of Smad-independent TGF-β signaling. This study investigated the role of TAK1 in the epithelial-mesenchymal transition (EMT) lens epithelial cells. TAK1 was overexpressed in the HLE B-3 cell line by transfecting TAK1-pcDNA3 and TAK1-binding protein 1 (TAB1)-pcDNA3 plasmids. The expression levels of TAK1, phospho-TAK1, E-cadherin, and fibronectin were detected by Western blot analysis and immunocytofluorescence to analyze the effects of overexpression. The levels of α-SMA and type I collagen were analyzed by real-time PCR. Quantitative data were analyzed by Student's t test or one-way analysis of variance (ANOVA) (multiple comparisons using LSD test). Western blot analysis showed in the TAK1-pcDNA3 plasmids group, expression of TAK1 proteins (1.00±0.03) with a maximum upregulation of approximately 80% at 24 h than it was in the control group (0.19±0.09)(t=8.02, P< 0.01); Western blot analysis showed in the TAB1-pcDNA3 plasmids group, expression of TAB1 proteins (1.00±0.02) with a maximum upregulation of approximately 78% at 24 h than it was in the control group (0.22±0.08)(t=7.63, P<0.01). The levels of E-cadherin/Beta-actin had significant differences among control, overexpression of TAK1 together with TAB1, overexpression of TAK1, and overexpression of TAB1 (1.00±0.02, 0.12±0.03, 0.98±0.09, 0.92±0.08;F=31.03, P<0.01). The levels of fibronectin/Beta-actin had significant differences among control, overexpression of TAK1 together with TAB1, overexpression of TAK1, and overexpression of TAB1 (0.11±0.03, 1.00±0.05, 0.16±0.04, 0.21±0.05;F=35.12, P<0.01). Overexpression of TAK1 with TAB1 resulted in upregulated expression of fibronectin, and downregulated expression of E-cadherin. The expression of E-cadherin was increased and the expression of fibronectin was decreased by TAK1 siRNA and TAK1 chemical inhibitors in the presence of TGF-β2. These data reveal that TAK1 can induce the EMT of HLE cells, and the inhibition of TAK1 phosphorylation may be a potential novel therapeutic target for the prevention and treatment of posterior capsule opacification. (Chin J Ophthalmol, 2016, 52: 278-284).

Hyperglycemia Enhances the Production of Amyloid β1-42 in the Lenses of Otsuka Long-Evans Tokushima Fatty Rats, a Model of Human Type 2 Diabetes.

It has been reported that the accumulation of amyloid β1-42 (Aβ1-42) in human lenses can cause some forms of lens opacification. However, the factors leading to changes in the accumulation of Aβ in the lens remain obscure. In this study, we investigate the effect of hyperglycemia on Aβ1-42 accumulation in lenses. Otsuka Long-Evans Tokushima Fatty (OLETF) rats and the human lens epithelial cell line SRA 01/04 (HLE cells) were used. The expression of mRNA was determined using a quantitative real-time RT-PCR method; Aβ1-42 levels were analyzed by an ELISA method. Otsuka Long-Evans Tokushima Fatty rats at more than 20 weeks of age develop diabetes mellitus with hyperglycemia. Additionally, the levels of the mRNAs for Aβ1-42, amyloid precursor proteins (APP), β-(BACE1), and·γ-secretase (PS) rise in the lenses of OLETF rats with age; high Aβ1-42 levels are observed in the lens capsule-epithelium and cortex. The enhanced expression of the genes for APP, BACE1, and PS in the lenses of OLETF rats is prevented by food restriction (25 g/d/rat). When the effect of glucose levels on the production of Aβ1-42 was investigated in the human lens epithelial cell line SRA 01/04 (HLE cells), the mRNA levels for APP, BACE1, and PS, as well as Aβ1-42 protein levels, were significantly higher under high glucose conditions (20 mM) than under normal glucose conditions (5.6 mM). High glucose leads to the increased expression of genes related to Aβ production, resulting in the accumulation of Aβ in the lens.

Polymorphism rs7278468 is associated with Age-related cataract through decreasing transcriptional activity of the CRYAA promoter.

CRYAA plays critical functional roles in lens transparency and opacity, and polymorphisms near CRYAA have been associated with age-related cataract (ARC). This study examines polymorphisms in the CRYAA promoter region for association with ARC and elucidates the mechanisms of this association. Three SNPs nominally associated with ARC were identified in the promoter region of CRYAA: rs3761382 (P = 0.06, OR (Odds ratio) = 1.5), rs13053109 (P = 0.04, OR = 1.6), rs7278468 (P = 0.007, OR = 0.6). The C-G-T haplotype increased the risk for ARC overall (P = 0.005, OR = 1.8), and both alleles and haplotypes show a stronger association with cortical cataract (rs3761382, P = 0.002, OR = 2.1; rs13053109, P = 0.002, OR = 2.1; rs7278468, P = 0.0007, OR = 0.5; C-G-T haplotype, P = 0.0003, OR = 2.2). The C-G-T risk haplotype decreased transcriptional activity through rs7278468, which lies in a consensus binding site for the transcription repressor KLF10. KLF10 binding inhibited CRYAA transcription, and both binding and inhibition were greater with the T rs7278468 allele. Knockdown of KLF10 in HLE cells partially rescued the transcriptional activity of CRYAA with rs7278468 T allele, but did not affect activity with the G allele. Thus, our data suggest that the T allele of rs7278468 in the CRYAA promoter is associated with ARC through increasing binding of KLF-10 and thus decreasing CRYAA transcription.

Selenoprotein R Protects Human Lens Epithelial Cells against D-Galactose-Induced Apoptosis by Regulating Oxidative Stress and Endoplasmic Reticulum Stress.

Selenium is an essential micronutrient for humans. Much of selenium’s beneficial influence on health is attributed to its presence within 25 selenoproteins. Selenoprotein R (SelR), known as methionine sulfoxide reductase B1 (MsrB1), is a selenium-dependent enzyme that, like other Msrs, is required for lens cell viability. In order to investigate the roles of SelR in protecting human lens epithelial (hLE) cells against damage, the influences of SelR gene knockdown on d-galactose-induced apoptosis in hLE cells were studied. The results showed that both d-galactose and SelR gene knockdown by siRNA independently induced oxidative stress. When SelR-gene-silenced hLE cells were exposed to d-galactose, glucose-regulated protein 78 (GRP78) protein level was further increased, mitochondrial membrane potential was significantly decreased and accompanied by a release of mitochondrial cytochrome c. At the same time, the apoptosis cells percentage and the caspase-3 activity were visibly elevated in hLE cells. These results suggested that SelR might protect hLE cell mitochondria and mitigating apoptosis in hLE cells against oxidative stress and endoplasmic reticulum (ER) stress induced by d-galactose, implying that selenium as a micronutrient may play important roles in hLE cells.

Alpha fetoprotein plays a critical role in promoting metastasis of hepatocellular carcinoma cells

A high level of serum alpha fetoprotein (AFP) is positively associated with human hepatocellular carcinoma (HCC) carcinogenesis and metastasis; however, the function of AFP in HCC metastasis is unknown. This study has explored the effects of AFP on regulating metastatic and invasive capacity of human HCC cells. Forty-seven clinical patients' liver samples were collected and diagnosed; HCC cells line, Bel 7402 cells (AFP-producing) and liver cancer cell line cells (non-AFP-producing) were selected to analyse the role of AFP in the metastasis of HCC cells. The results indicated that high serum concentration of AFP was positively correlated with HCC intrahepatic, lymph nodes and lung metastasis. Repressed expression of AFP significantly inhibited the capability of migration and invasion of Bel 7402 cells, expression of keratin 19 (K19), epithelial cell adhesion molecule (EpCAM), matrix metalloproteinase 2/9 (MMP2/9) and CXC chemokine receptor 4 (CXCR4) were also down-regulated in Bel 7402 cells; migration and invasion, expression of K19, EpCAM, MMP2/9 and CXCR4 were significantly enhanced when HLE cells were transfected with AFP-expressed vector. The results demonstrated that AFP plays a critical role in promoting metastasis of HCC; AFP promoted HCC cell invasion and metastasis via up-regulating expression of metastasis-related proteins. Thus, AFP may be used as a novel therapeutic target for treating HCC patients.

Recreating the Human Limbal Epithelial Stem Cell Niche with Bioengineered Limbal Crypts

ABSTRACTPurpose: Creation of an in vitro model incorporating specific features that characterize a particular stem niche would allow researchers to study stem cell behavior in a more physiological environment.Materials and methods: We have developed a tissue engineering process (RAFT) that rapidly and reliably creates bioengineered limbal crypts (BLCs) in the surface of collagen-based tissue equivalents (TEs). These BLCs mimic the three-dimensional topography of the limbal crypts (LCs), located in the limbal region of the human cornea, which are home to a population of limbal epithelial stem cells (LESCs).Results: Human limbal epithelial (hLE) cells occupying our BLCs expressed putative LESC markers such as ΔNp63α and Bmi1 and produced basement membrane proteins such as laminin β1 and laminin γ3; expression patterns are very similar to those seen in native LCs. Human limbal stromal cells elongate and align along the edge of native LCs and in our RAFT TEs, human limbal fibroblasts (hLFs) also appeared to exhibit this alignment and elongation behavior in response to the BLC topography.Conclusions: We have demonstrated that we can maintain an immature population of hLE cells and aligned stromal cells in our BLCs to mimic some elements of the complexity of the human LESC niche.

Alpha Fetoprotein Plays Antagonistic Role in Benzyl-Isothiocyanate Arresting Cell Cycle in Liver Cancer Cells

Background: To investigate the effect of alpha fetoprotein (AFP) on benzyl-isothiocyanate (BITC) arresting cell cycle in human liver cancer cells line in vitro, and explore the possible role mechanism of BITC inhibited proliferation of hepatocellular carcinoma (HCC) cells. Methods: In this study, we selected HCC cells lines, Bel 7402 and HLE for test. Fluorescent microscopy and Western blotting were applied to observe the transfected effect and expression of proteins; MTT assay the proliferation of HCC cells; Flow cytometry method was used to detect the cellular cycle; RNA interference was used to test and expressed vector constructed technology were performed to silence and induce expression of AFP, respectively. Results: Analysis showed BITC had a significant inhibitory effect on the proliferation of HCC cells in dosedependent manner, inhibitory effect was enhanced while Bel 7402 cells were transfected with AFP-siRNA vectors but attenuated in HLE cells while transfected with pcDNA3.1-afp vectors. The growth ratio of AFP-siRNA transfected Bel 7402 cells and pcDNA3.1-afp transfected HLE cells followed treated with 80 μmol/L BITC were (42.43 ± 4.92)% (P<0.05 vs Bel 7402 cells group) and (40.13 ± 4.99)% (P<0.05 vs HLE cells group). BITC could obviously induce cell cycle G2/M phase arrest in theses HCC cells; The induction effect was enhanced in AFP-siRNA transfected Bel 7402 cells but attenuated in pcDNA3.1-afp transfected HLE cells. BITC inhibited the expression of cell cycle related proteins, cyclin B1, CDK1, Cdc25c but stimulated expression of Weel in Bel 7402 cells and HLE cells, and such effect was enhanced in AFP-siRNA transfected Bel 7402 cells but attenuated in pcDNA3.1-afp transfected HLE cells. Conclusions: BITC could inhibit the growth of HCC cells and induce cell cycle G2/M phase arrest through down regulating the expression of cyclin B1, CDK1, Cdc25c and up regulating the expression of Weel; AFP played an antagonistic role in BITC arresting cell cycle in HCC cells.

Epigenetic regulation of proliferation and invasion in hepatocellular carcinoma cells by CBP/p300 histone acetyltransferase activity.

Altered epigenetic control of gene expression plays a substantial role in tumor development and progression. Accumulating studies suggest that somatic mutations of CREB binding proteins (CBP)/p300 occur in some cancer cells. CBP/p300 possess histone acetyltransferase (HAT) activity, and are involved in many cellular processes. In this study, we investigated the expression and functional role of CBP/p300 in hepatocellular carcinoma (HCC) using the specific inhibitor C646 of CBP/p300 HAT activity. We examined its effect on several apoptosis-related proteins and invasion-related genes. The results showed that CBP/p300 were highly expressed in HCC tissues and that expression of p300, but not of CBP, was strongly correlated with the malignant character of HCC. C646 inhibited proliferation of HCC cell lines in a dose dependent manner. C646 significantly augmented TRAIL-induced apoptotic sensitivity, which was accompanied by reduced levels of survivin, in HepG2, HLE and SK-HEP1 cells. C646 significantly inhibited invasion of Huh7, HLE and SK-HEP1 cells. The level of matrix metallopeptidase 15 (MMP15) mRNA expression was significantly reduced, whereas the level of laminin alpha 3 (LAMA3) and secreted phosphoprotein 1 (SPP1) mRNA expression was significantly increased in Huh7 cells following exposure to C646. In conclusion, our results suggest that CBP/p300 HAT activity has an important role in malignant transformation, proliferation, apoptotic sensitivity and invasion in HCC. CBP/p300 could be a promising therapeutic target in HCC.

Knockdown of 15-kDa selenoprotein (Sep15) increases hLE cells' susceptibility to tunicamycin-induced apoptosis.

In this work, we investigated the effect of Sep15 gene knockdown on apoptosis in human lens epithelial (hLE) cells, trying to understand the relevance of Sep15 to cataract formation in the Sep15 knockout (KO) mice. The results showed that sole knockdown of Sep15 by RNA interference did not result in apoptosis; however, reduction of Sep15 expression aggravated tunicamycin (Tm)-induced cell apoptosis and caspases activation. Furthermore, Tm-induced mitochondrial dysfunction was also exacerbated under the Sep15 knockdown condition by measurement of mitochondrial membrane potential decrease and human cytochrome c release into cytosol. Interestingly, the knockdown of Sep15 exacerbated Tm-induced oxidative stress while endoplasmic reticulum (ER) stress was not correspondingly elevated. These results suggest that the protective role of Sep15 against Tm-induced apoptosis in hLE cells is operated via inhibiting oxidative stress rather than regulating Tm-induced ER stress, and the protective role becomes dependent on Sep15 only in acute stress condition.

MicroRNA profiles in cisplatin-induced apoptosis of hepatocellular carcinoma cells.

Cisplatin [cis-diamminedichloroplatinum (II)], is a platinum coordination compound that is commonly used to treat hepatocellular carcinoma (HCC). It is also one of the most compelling anticancer drugs. Recent studies suggest that cisplatin may reduce cancer risk and improve prognosis. However, the antitumor mechanism of cisplatin in several types of cancers, including HCC, has not been elucidated. The goal of the present study was to evaluate the effects of cisplatin on the proliferation of HCC cells in vitro and to determine which microRNAs (miRNAs) are associated with the anticancer effects of cisplatin in vitro. We used various human HCC-derived cell lines to study the effects of cisplatin on human HCC cells. Cisplatin led to a strong dose- and time- dependent inhibition of cell proliferation in HLE, HLF, HuH7, Li-7, Hep3B and HepG2 cells in vitro. Cisplatin also blocked the progression of the cell cycle in the G0/G1 phase, which inhibited cyclin D1 and induced apoptosis. In addition, miRNA expression was markedly altered by treatment with cisplatin in vitro. Therefore, various miRNAs induced by cisplatin may also contribute to the suppression of cellular proliferation and apoptosis. Our results demonstrate that cisplatin inhibits the growth of HCC, possibly through the induction of G1 cell cycle arrest and apoptosis through the alteration of microRNA expression.

Galectin-9 suppresses the growth of hepatocellular carcinoma via apoptosis in vitro and in vivo.

Galectin-9, a soluble β-galactoside-binding animal lectin, evokes apoptosis in various human cancer cell lines. The galectin-9 antitumor effect against hepatocellular carcinoma (HCC) is, however, unknown. We investigated whether galectin-9 suppresses HCC growth in vitro and in vivo. We assessed the antitumor effect of galectin-9 on HCC cells by conducting WST-8 assay in vitro and xenograft model analysis in vivo. Galectin-9-induced apoptosis was evaluated by FACS and ELISA in vitro and by TUNEL stain in vivo. Cell cycle alteration was profiled by FACS. Caspases were profiled by colorimetry. MicroRNAs related to the galectin-9 antitumor effects were determined using microarrays, and their antitumor effect was confirmed in a transfection study in vitro. The expression levels of the target proteins of the miRNAs extracted above were analyzed by western blot analysis. To summarize the results, galectin-9 inhibited the growth of the HCC cell lines HLE and Li-7 in vitro and Li-7 in vivo inducing apoptosis. Cell cycle turnover was not arrested in HLE and Li-7 cells in vitro. miR-1246 was similarly extracted both in vitro and in vivo, which sensitized Li-7 cells to apoptosis when transfected into the cells. DYRK1A, a target protein of miR-1246 was downregulated in Li-7 cells. Caspase-9 was upregulated in Li-7 cells in vitro and in vivo. In conclusion, galectin-9 inhibited the growth of HCC cells by apoptosis, but not cell cycle arrest, in vitro and in vivo. miR-1246 mediated signals of galectin-9, possibly through miR-1246-DYRK1A-caspase-9 axis. Galectin-9 might be a candidate agent for HCC chemotherapy.

Effect of the anti-diabetic drug metformin in hepatocellular carcinoma in vitro and in vivo.

Metformin is a commonly used oral anti-hyperglycemic agent of the biguanide family. Recent studies suggest that metformin may reduce cancer risk and improve prognosis. However, the antitumor mechanism of metformin in several types of cancers, including hepatocellular carcinoma (HCC), has not been elucidated. The goal of the present study was to evaluate the effects of metformin on HCC cell proliferation in vitro and in vivo, and to study microRNAs (miRNAs) associated with the antitumor effect of metformin in vitro. We used the cell lines Alex, HLE and Huh7, and normal hepatocytes to study the effects of metformin on human HCC cells. In an in vivo study, athymic nude mice bearing xenograft tumors were treated with metformin or left untreated. Tumor growth was recorded after 4 weeks, and the expression of cell cycle-related proteins was determined. Metformin inhibited the proliferation of Alex, HLE and Huh7 cells in vitro and in vivo. Metformin blocked the cell cycle in G0/G1 in vitro and in vivo. This blockade was accompanied by a strong decrease of G1 cyclins, especially cyclin D1, cyclin E and cyclin-dependent kinase 4 (Cdk4). In addition, microRNA (miRNA) expression was markedly altered by the treatment with metformin in vitro and in vivo. In addition, various miRNAs induced by metformin also may contribute to the suppression of tumor growth. Our results demonstrate that metformin inhibits the growth of HCC, possibly by inducing G1 cell cycle arrest through the alteration of microRNAs.

Effect of the anti-diabetic drug metformin in hepatocellular carcinoma invitro and invivo.

Metformin is a commonly used oral anti-hyperglycemic agent of the biguanide family. Recent studies suggest that metformin may reduce cancer risk and improve prognosis. However, the antitumor mechanism of metformin in several types of cancers, including hepatocellular carcinoma (HCC), has not been elucidated. The goal of the present study was to evaluate the effects of metformin on HCC cell proliferation invitro and invivo, and to study microRNAs (miRNAs) associated with the antitumor effect of metformin invitro. We used the cell lines Alex, HLE and Huh7, and normal hepatocytes to study the effects of metformin on human HCC cells. In an invivo study, athymic nude mice bearing xenograft tumors were treated with metformin or left untreated. Tumor growth was recorded after 4weeks, and the expression of cell cycle‑related proteins was determined. Metformin inhibited the proliferation of Alex, HLE and Huh7 cells invitro and invivo. Metformin blocked the cell cycle in G0/G1 invitro and invivo. This blockade was accompanied by a strong decrease of G1 cyclins, especially cyclinD1, cyclinE and cyclin-dependent kinase4 (Cdk4). In addition, microRNA (miRNA) expression was markedly altered by the treatment with metformin invitro and invivo. In addition, various miRNAs induced by metformin also may contribute to the suppression of tumor growth. Our results demonstrate that metformin inhibits the growth of HCC, possibly by inducing G1 cell cycle arrest through the alteration of microRNAs.

Effect of methionine sulfoxide reductase B1 (SelR) gene silencing on peroxynitrite-induced F-actin disruption in human lens epithelial cells

F-actin plays a crucial role in fundamental cellular processes, and is extremely susceptible to peroxynitrite attack due to the high abundance of tyrosine in the peptide. Methionine sulfoxide reductase (Msr) B1 is a selenium-dependent enzyme (selenoprotein R) that may act as a reactive oxygen species (ROS) scavenger. However, its function in coping with reactive nitrogen species (RNS)-mediated stress and the physiological significance remain unclear. Thus, the present study was conducted to elucidate the role and mechanism of MsrB1 in protecting human lens epithelial (hLE) cells against peroxynitrite-induced F-actin disruption. While exposure to high concentrations of peroxynitrite and gene silencing of MsrB1 by siRNA alone caused disassembly of F-actin via inactivation of extracellular signal-regulated kinase (ERK) in hLE cells, the latter substantially aggravated the disassembly of F-actin triggered by the former. This aggravation concurred with elevated nitration of F-actin and inactivation of ERK compared with that induced by the peroxynitrite treatment alone. In conclusion, MsrB1 protected hLE cells against the peroxynitrite-induced F-actin disruption, and the protection was mediated by inhibiting the resultant nitration of F-actin and inactivation of ERKs.