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1.
Cancer Cell Int ; 21(1): 616, 2021 Nov 22.
Article in English | MEDLINE | ID: mdl-34809621

ABSTRACT

BACKGROUND: UCA1 is frequently upregulated in a variety of cancers, including CRC, and it can play an oncogenic role by various mechanisms. However, how UCA1 is regulated in cancer is largely unknown. In this study, we aimed to determine whether RNA methylation at N6-methyladenosine (m6A) can impact UCA1 expression in colorectal cancer (CRC). METHODS: qRT-PCR was performed to detect the level of UCA1 and IGF2BP2 in CRC samples. CRISPR/Cas9 was employed to knockout (KO) UCA1, METTL3 and WTAP in DLD-1 and HCT-116 cells, while rescue experiments were carried out to re-express METTL3 and WTAP in KO cells. Immunoprecipitation using m6A antibody was performed to determine the m6A modification of UCA1. In vivo pulldown assays using S1m tagging combined with site-direct mutagenesis was carried out to confirm the recognition of m6A-modified UCA1 by IGF2BP2. Cell viability was measured by MTT and colony formation assays. The expression of UCA1 and IGF2BP2 in TCGA CRC database was obtained from GEPIA ( http://gepia.cancer-pku.cn ). RESULTS: Our results revealed that IGF2BP2 serves as a reader for m6A modified UCA1 and that adenosine at 1038 of UCA1 is critical to the recognition by IGF2BP2. Importantly, we showed that m6A writers, METTL3 and WTAP positively regulate UCA1 expression. Mechanically, IGF2BP2 increases the stability of m6A-modified UCA1. Clinically, IGF2BP2 is upregulated in CRC tissues compared with normal tissues. CONCLUSION: These results suggest that m6A modification is an important factor contributing to upregulation of UCA1 in CRC tissues.

2.
Genes Dis ; 8(1): 6-7, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33569509

ABSTRACT

Circular RNAs (circRNAs) are playing emerging role in the pathogenesis of cancers, but the mechanisms still unknown. In the recent issue of the Nature Communications, Chen and colleagues have demonstrated that YTHDC1 facilitates N6-methyladenosine modified circNSUN2 cytoplasmic export and the circNSUN2/IGF2BP2/HMGA2 complex stabilizes HMGA2 to promote colorectal liver metastasis. These discoveries not only expand our understanding of circRNAs biology in tumor, but also demonstrate that m6A modification plays a key role for circRNAs in RNA metabolism. Therefore, these findings indicate that circRNAs may be a new approach for therapeutic target of cancers.

3.
Genes Dis ; 7(4): 598-605, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33335959

ABSTRACT

Increasing evidence indicates that mRNAs are often subject to posttranscriptional modifications. Among them, N6-methyladenosine (m6A), which has been shown to play key roles in RNA splicing, stability, nuclear export, and translation, is the most abundant modification of RNA. Extensive studies of m6A modification of mRNAs have been carried out, while little is known about m6A modification of long non-coding RNAs (lncRNAs). Recently, several studies reported m6A modification of lncRNAs. In this review, we focus on these m6A-modified lncRNAs and discuss possible functions of m6A modification.

5.
J Clin Neurosci ; 65: 125-133, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31036506

ABSTRACT

The present study focused on the novel roles and the underlying mechanisms of miR-135b in pyroptosis of MPP+-induced Parkinson's disease (PD). We established an in vitro PD model induced by MPP+. Our results demonstrated miR-135b was lower while FoxO1 was inversely higher in MPP+-treated SH-SY5Y and PC-12 cells. Luciferase reporter assay showed FoxO1 was a downstream target of miR-135b. MiR-135b mimics suppressed MPP+-induced pyroptosis and the upregulation of TXNIP, NLRP3, Caspase-1, ASC, GSDMDNterm and IL-1ß. Moreover, FoxO1 overexpression had no effect on miR-135b but reversed its own downregulation caused by miR-135b mimics. Meanwhile, overexpression of FoxO1 abolished the inhibitory effects of miR-135b on pyroptosis and reversed the downregulation of pyroptotic genes and LDH release. In summary, miR-135b played a protective role in Parkinson's disease via inhibiting pyroptosis by targeting FoxO1. MiR-135b might serve as a potential therapeutic target in the treatment of Parkinson's disease.


Subject(s)
Forkhead Box Protein O1/metabolism , Inflammasomes/metabolism , MicroRNAs/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Parkinson Disease/genetics , Pyroptosis/genetics , Carrier Proteins/metabolism , Humans , Intracellular Signaling Peptides and Proteins , Neoplasm Proteins/genetics , Phosphate-Binding Proteins , Up-Regulation
6.
J Biomed Nanotechnol ; 15(5): 1052-1060, 2019 May 01.
Article in English | MEDLINE | ID: mdl-30890235

ABSTRACT

A primerless amplification suitable for enrichment of particular genotype cfDNA which is a one-dimensional material has been developed. This primerless amplification coordinated by two thermostable enzymes of endonuclease and proofreading polymerase, functions as a genotype switch in analyzing cfDNA. The endonuclease digests the wild-typed fragments into mega-primer and discriminately destroys the wild-type DNA alleles. The DNA polymerase proofreads the megaprimer and then extends the mega-primer using the mutant DNA as the template. The prototypes of this technology were applied to two hotspot mutations of APC and EGFR with confirmed by DNA sequencing analysis. Genotype switch was then employed to clinical cfDNA assay targeting PIK3CA. Data from the clinical application suggest its potential in early cancer diagnosis.


Subject(s)
Circulating Tumor DNA/analysis , Neoplasms , DNA , Humans , Mutation
7.
Genes Dis ; 6(1): 6-15, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30906827

ABSTRACT

Accumulating evidence indicates that long non-coding RNAs (lncRNAs) can play a pivotal role in regulation of diverse cellular processes. In particular, lncRNAs can serve as master gene regulators at transcriptional and posttranscriptional levels, leading to tumorigenesis. In this review, we discuss latest developments in lncRNA-meditated gene expression at the post-transcriptional level, including gene splicing, mRNA stability, protein stability and nuclear trafficking.

8.
Cancer Discov ; 7(10): 1116-1135, 2017 10.
Article in English | MEDLINE | ID: mdl-28667006

ABSTRACT

Cholangiocarcinoma (CCA) is a hepatobiliary malignancy exhibiting high incidence in countries with endemic liver-fluke infection. We analyzed 489 CCAs from 10 countries, combining whole-genome (71 cases), targeted/exome, copy-number, gene expression, and DNA methylation information. Integrative clustering defined 4 CCA clusters-fluke-positive CCAs (clusters 1/2) are enriched in ERBB2 amplifications and TP53 mutations; conversely, fluke-negative CCAs (clusters 3/4) exhibit high copy-number alterations and PD-1/PD-L2 expression, or epigenetic mutations (IDH1/2, BAP1) and FGFR/PRKA-related gene rearrangements. Whole-genome analysis highlighted FGFR2 3' untranslated region deletion as a mechanism of FGFR2 upregulation. Integration of noncoding promoter mutations with protein-DNA binding profiles demonstrates pervasive modulation of H3K27me3-associated sites in CCA. Clusters 1 and 4 exhibit distinct DNA hypermethylation patterns targeting either CpG islands or shores-mutation signature and subclonality analysis suggests that these reflect different mutational pathways. Our results exemplify how genetics, epigenetics, and environmental carcinogens can interplay across different geographies to generate distinct molecular subtypes of cancer.Significance: Integrated whole-genome and epigenomic analysis of CCA on an international scale identifies new CCA driver genes, noncoding promoter mutations, and structural variants. CCA molecular landscapes differ radically by etiology, underscoring how distinct cancer subtypes in the same organ may arise through different extrinsic and intrinsic carcinogenic processes. Cancer Discov; 7(10); 1116-35. ©2017 AACR.This article is highlighted in the In This Issue feature, p. 1047.


Subject(s)
Bile Duct Neoplasms/genetics , Cholangiocarcinoma/genetics , Epigenomics/methods , Genome-Wide Association Study/methods , CpG Islands , DNA Methylation , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , Humans , Receptor, ErbB-2/genetics , Receptor, Fibroblast Growth Factor, Type 2/genetics , Tumor Suppressor Protein p53/genetics
9.
Oncotarget ; 8(20): 33694-33703, 2017 May 16.
Article in English | MEDLINE | ID: mdl-28402270

ABSTRACT

BACKGROUND: Aldo-keto reductase family 1, member B10 (AKR1B10), is known to be significantly induced in the cells of various cancers such as breast cancer. However, the mechanisms of AKR1B10 promoting tumorigenesis in breast cancer remain unclear. In the present study, we demonstrated the potential role and mechanism of AKR1B10 in the invasion and migration of breast cancer cells. METHODS: The expression level of AKR1B10 in breast carcinoma, para-carcinoma and cancer tissues were detected by immunohistochemical evaluation and real-time polymerase chain reaction (RT-PCR), and the correlationships between AKR1B10 expression and clinicopathological features in breast cancer patients (n=131) were investigated. AKR1B10 was ectopically expressed in MCF-7 cells or silenced in BT-20 cells. The roles of AKR1B10 expression in the migration and invasion of MCF-7 cells and BT-20 cells were explored by wound healing assay, transwell migration assay and transwell matrigel invasion assay, and finally the activation level of extracellular signal-regulated kinase 1/2 (EKR1/2) activation and the expression level of matrix metalloproteinase-2 (MMP2) and vimentin in MCF-7 and BT-20 cells were measured by western blot. RESULTS: We found that AKR1B10 expression was increased in malignant tissues, which was correlated positively with tumor size, lymph node metastasis (p<0.05). MCF-7/AKR1B10 cells displayed a higher ability of migration (43.57±1.04%) compared with MCF-7/vector cells (29.12±1.34%) in wound healing assay, and the migrated cell number of MCF-7/AKR1B10 was more (418.43±9.62) than that of MCF-7/vector (222.43±17.75) in transwell migration assay without matrigel. We furtherly confirmed MCF-7/AKR1B10 cells invaded faster compared with MCF-7/vector cells by transwell matrigel invasion assay. Finally, we found AKR1B10 induced the migration and invasion of MCF-7 and BT-20 cells by activating EKR signaling, which promoted the expressions of MMP2 and vimentin. PD98059, a specific inhibitor of the activation of MEK, blocked the migration and invasion by inhibiting the expression of MMP2 and vimentin. CONCLUSIONS: AKR1B10 is overexpressed in breast cancer, and promotes the migration and invasion of MCF-7 and BT-20 cells by activating ERK signaling pathway.


Subject(s)
Aldo-Keto Reductase Family 1 member B10/genetics , Aldo-Keto Reductase Family 1 member B10/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , MAP Kinase Signaling System , Adult , Aged , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Movement , Cell Proliferation , Female , Gene Expression , Humans , MCF-7 Cells , Middle Aged , Neoplasm Grading , Neoplasm Metastasis , Neoplasm Staging
10.
Oncotarget ; 8(9): 16075-16083, 2017 Feb 28.
Article in English | MEDLINE | ID: mdl-28039476

ABSTRACT

Recent development of cutting edge research found that long noncoding RNAs (lncRNAs) plays important roles in carcinogenesis and progression. In Southeast Asia and North Africa, nasopharyngeal carcinoma (NPC) is the most common aggressive squamous cell carcinoma. Nasopharyngeal carcinoma is most frequently occurring in males. However, nasopharyngeal carcinoma is caused by a combination of several factors as viral, environmental factors, and heredity. Till now, the potential pathway or mechanism of NPC is not well known. In our present review, we strongly emphasized on long noncoding RNAs (lncRNAs) and its significant role in nasopharyngeal carcinoma. It has been showed that lncRNAs regulate the development and progression of different types of cancers, including NPC. In addition, it has been found that chromatin organization, transcriptional and post-transcriptional events are regulated by lncRNAs. Our present review summarizes the roles of lncRNAs in nasopharyngeal carcinoma and provides an overview of the feasibility of lncRNAs as diagnosis, prognosis and potential treatment for NPC patients.


Subject(s)
Carcinoma , Nasopharyngeal Neoplasms , RNA, Long Noncoding , Humans , Carcinogenesis/genetics , Carcinoma/genetics , Cell Line, Tumor , Disease Progression , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/genetics , Prognosis , RNA, Long Noncoding/genetics
11.
Int J Ophthalmol ; 9(8): 1200-6, 2016.
Article in English | MEDLINE | ID: mdl-27588276

ABSTRACT

AIM: To investigate choroidal thickness in pregnant women and compare the measurements with those of normal nonpregnant women. METHODS: Using enhanced depth imaging optical coherence tomography (EDI-OCT), choroidal thickness was measured at the fovea and at 1 mm and 3 mm superior, inferior, temporal, and nasal to the fovea in both healthy pregnant women and nonpregnant women. Pearson correlation analysis was performed to evaluate the relationships between subfoveal choroidal thickness (SFCT) and the demographic and ocular parameters. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed-effects model when Meta-analyses were conducted. RESULTS: Comparison of choroidal thickness between the groups showed that it was significantly greater in healthy pregnant women's eyes than in normal nonpregnant women's eyes at all locations except at 3 mm superior and 3 mm temporal from the fovea (P<0.05). The mean SFCT was 344.13±50.94 µm in healthy pregnant women's eyes and 315.03±60.57 µm in normal nonpregnant women's eyes, with a statistically significant difference (P=0.008). Pearson correlation analysis showed that age and axial length were significantly related to SFCT in healthy pregnant women, normal nonpregnant women, and all subjects. The results of our cross-sectional study were consistent with the results of the further Meta-analysis, with a pooled weighted mean difference (WMD) of 33.66 µm (95% CI: 26.16 to 41.15) for SFCT. CONCLUSION: Our results, along with the comprehensive Meta-analysis, suggest that choroidal thickness in healthy pregnant women is greater than that in normal nonpregnant women.

12.
Int J Clin Exp Pathol ; 7(7): 3791-9, 2014.
Article in English | MEDLINE | ID: mdl-25120755

ABSTRACT

Mouse aldo-keto reductase family 1 member B8 (AKR1B8) has the highest similarity to human aldo-keto reductase family 1 member B10 (AKR1B10), a secretory protein through lysosomes-mediated non-classical secretory pathway. To identify whether AKR1B8 is secreted through the same pathway, we carried out this study. Self-developed sandwich ELISA and western blot were used to detect AKR1B8 in cells and culture medium of CT-26 murine colon carcinoma cells. AKR1B8 releases in an independent manner to Brefeldin A, an inhibitor of ER-to-Golgi classical secretion pathway. Several factors, which are involved in the non-classical secretion pathway, such as temperature, ATP and calcium ion, regulated AKR1B8 secretion from mouse colorectal cancer cells CT-26. Lysosomotropic NH4Cl increased AKR1B8 secretion, and AKR1B8 was located in isolated lysosomes. Therefore, AKR1B8 is a new secretory protein through the lysosomes-mediated non-classical pathway.


Subject(s)
Aldehyde Reductase/metabolism , Colonic Neoplasms/enzymology , Colonic Neoplasms/metabolism , Lysosomes/metabolism , Aldo-Keto Reductases , Animals , Blotting, Western , Cell Line, Tumor , Enzyme-Linked Immunosorbent Assay , Mice , Recombinant Proteins/metabolism
13.
Int J Ophthalmol ; 7(1): 51-6, 2014.
Article in English | MEDLINE | ID: mdl-24634863

ABSTRACT

AIM: To investigate the effect of 5-Aza-2'-deoxycytidine (5-Aza-CdR), a DNA methyltransferase (DNMT) inhibitor, on the growth and survival of the Chinese retinoblastoma (RB) cell line HXO-RB44. METHODS: The DNA methylation status of the Ras association domain family (RASSF1A) promoter in the presence of 5-Aza-CdR at different concentrations was analyzed by methylation-specific polymerase chain reaction (MSP). RASSF1A mRNA and protein levels were measured by semiquantitative RT-PCR and immunohistochemistry staining, respectively, when cells were treated with 5.0µmol/L of 5-Aza-CdR. The effect of 5.0µmol/L 5-Aza-CdR on the proliferation and viability of HXO-RB44 cells was examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. RESULTS: 5-Aza-CdR efficiently induced cell cycle arrest at G0/G1 and apoptotic death in HXO-RB44 cells. MSP analysis showed that unmethylated RASSF1A DNA increased and methylated RASSF1A decreased in a dose-dependent manner in a range of 0.5-5.0µmol/L 5-Aza-CdR. Accordingly, RASSF1A expression was reactivated at both mRNA and protein levels. Incubation time of 5-Aza-CdR treatment also functioned as a factor for the demethylation status of RASSF1A promoter DNA, with a plateau on day four. 5-Aza-CdR at 5.0µmol/L completely demethylated the RASSF1A promoter in HXO-RB44 cells on day four, and as a result, RASSF1A expression increased significantly from day 4 to day 7. CONCLUSION: 5-Aza-CdR inhibits the growth of the HXO-RB44 RB cell line and induces apoptosis by demethylating the RASSF1A gene.

14.
Int J Cancer ; 131(6): E862-71, 2012 Sep 15.
Article in English | MEDLINE | ID: mdl-22539036

ABSTRACT

Aldo-keto reductase 1B10 (AKR1B10) is a secretory protein that is upregulated with tumorigenic transformation of human mammary epithelial cells. This study demonstrated that AKR1B10 was overexpressed in 20 (71.4%) of 28 ductal carcinomas in situ, 184 (83.6%) of 220 infiltrating carcinomas and 28 (87.5%) of 32 recurrent tumors. AKR1B10 expression in breast cancer was correlated positively with tumor size (p = 0.0012) and lymph node metastasis (p = 0.0123) but inversely with disease-related survival (p = 0.0120). Univariate (p = 0.0077) and multivariate (p = 0.0192) analyses both suggested that AKR1B10, alone or together with tumor size and node status, is a significant prognostic factor for breast cancer. Silencing of AKR1B10 in BT-20 human breast cancer cells inhibited cell growth in culture and tumorigenesis in female nude mice. Importantly, AKR1B10 in the serum of breast cancer patients was significantly increased to 15.18 ± 9.08 ng/ml [n = 50; 95% confidence interval (CI), 12.60-17.76], with a high level up to 58.4 ng/ml, compared to 3.34 ± 2.27 ng/ml in healthy donors (n = 60; 95% CI, 2.78-3.90). In these patients, AKR1B10 levels in serum were correlated with its expression in tumors (r = 0.8066; p < 0.0001). Together our data suggests that AKR1B10 is overexpressed in breast cancer and may be a novel prognostic factor and serum marker for this deadly disease.


Subject(s)
Aldehyde Reductase/physiology , Biomarkers, Tumor/blood , Breast Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Aldehyde Reductase/antagonists & inhibitors , Aldehyde Reductase/blood , Aldo-Keto Reductases , Animals , Breast Neoplasms/mortality , Cell Line, Tumor , Female , Humans , Lymphatic Metastasis , Mice , Mice, Nude , Middle Aged , Tissue Array Analysis
15.
Recent Pat Anticancer Drug Discov ; 7(2): 168-84, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22339356

ABSTRACT

Acetyl-CoA carboxylases (ACCs) play a rate-limiting role in fatty acid biosynthesis in plants, microbes, mammals and humans. ACCs have the activity of both biotin carboxylase (BC) and carboxyltransferase (CT), catalyzing carboxylation of Acetyl-CoA to malonyl-CoA. In the past years, ACCs have been used as targets for herbicides in agriculture and for drug discovery and development of human diseases, such as microbial infections, diabetes, obesity and cancer. A great number of small molecule ACC inhibitors have been developed, including natural and non-natural (artificial) products. These chemicals target BC reaction, CT reaction or ACC phosphorylation. This article provides a comprehensive review and updates of ACC inhibitors, with a focus on their therapeutic application in metabolic syndromes and malignant diseases. The patent status of common ACC inhibitors is discussed.


Subject(s)
Acetyl-CoA Carboxylase/antagonists & inhibitors , Enzyme Inhibitors/therapeutic use , Metabolic Diseases/drug therapy , Neoplasms/drug therapy , Acetyl-CoA Carboxylase/chemistry , Animals , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/therapeutic use , Antineoplastic Agents/metabolism , Antineoplastic Agents/therapeutic use , Bacterial Infections/drug therapy , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Female , Herbicides/chemistry , Herbicides/metabolism , Humans , Mice , Mycoses/drug therapy , Obesity/drug therapy , Patents as Topic , Rats
16.
Biochem J ; 442(2): 273-82, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22329800

ABSTRACT

AKR1B10 (aldo-keto reductase 1B10) is overexpressed in liver and lung cancer, and plays a critical role in tumour development and progression through promoting lipogenesis and eliminating cytotoxic carbonyls. AKR1B10 is a secretory protein and potential tumour marker; however, little is known about the regulatory mechanism of AKR1B10 expression. The present study showed that AKR1B10 is induced by mitogen EGF (epidermal growth factor) and insulin through the AP-1 (activator protein-1) signalling pathway. In human HCC (hepatocellular carcinoma) cells (HepG2 and Hep3B), EGF (50 ng/ml) and insulin (10 nM) stimulated endogenous AKR1B10 expression and promoter activity. In the AKR1B10 promoter, a putative AP-1 element was found at bp -222 to -212. Deletion or mutation of this AP-1 element abrogated the basal promoter activity and response to EGF and AP-1 proteins. This AP-1 element bound to nuclear proteins extracted from HepG2 cells, and this binding was stimulated by EGF and insulin in a dose-dependent manner. Chromatin immunoprecipitation showed that the AP-1 proteins c-Fos and c-Jun were the predominant factors bound to the AP-1 consensus sequence, followed by JunD and then JunB. The same order was followed in the stimulation of endogenous AKR1B10 expression by AP-1 proteins. Furthermore, c-Fos shRNA (short hairpin RNA) and AP-1 inhibitors/antagonists (U0126 and Tanshinone IIA) inhibited endogenous AKR1B10 expression and promoter activity in HepG2 cells cultured in vitro or inoculated subcutaneously in nude mice. U0126 also inhibited AKR1B10 expression induced by EGF. Taken together, these results suggest that AKR1B10 is up-regulated by EGF and insulin through AP-1 mitogenic signalling and may be implicated in hepatocarcinogenesis.


Subject(s)
Aldehyde Reductase/metabolism , Carcinoma, Hepatocellular/metabolism , Epidermal Growth Factor/pharmacology , Liver Neoplasms/metabolism , Transcription Factor AP-1/metabolism , Aldehyde Reductase/genetics , Aldo-Keto Reductases , Animals , Base Sequence , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , DNA Primers/genetics , Female , Genes, fos , Hep G2 Cells , Humans , Insulin/pharmacology , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Mice , Mice, Nude , Promoter Regions, Genetic , RNA, Small Interfering/genetics , Signal Transduction/drug effects , Transcription Factor AP-1/antagonists & inhibitors , Transcription Factor AP-1/genetics , Up-Regulation/drug effects
17.
Arch Virol ; 157(3): 413-21, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22160624

ABSTRACT

This study aimed to identify the characteristics of recombinant-adenovirus-modified PBMC-derived dendritic cells and their resistance to HIV-1 infection by integrating the CCR5∆32, CCR5siRNA, HIV-1 pol and HIV-1 int genes into a recombinant adenovirus vector using the AdEasy system. Dendritic cells (DCs) were isolated from human PBMCs from blood of healthy donors. The expression of CCR5∆32, CCR5, CXCR4 and HIV-1 p24 in PBMCs or modified cells was measured by western blot, p24 expression in cell lysates was measured by ELISA, and HIV-1 entry was measured by ß-galactosidase assay. Furthermore, T-cell immunity induced by the recombinant adenovirus was measured by ELISPOT assay. After the cells were modified by Ad-R5∆32siRNA, the expression of CCR5∆32 increased, while the expression of CCR5 and CXCR4 decreased. There was no adverse effect of adenoviral gene transfer on DC development. CD83 expression on the surface of mature DCs did not change after gene transfer. The expression of p24 remained at low levels in modified cells when challenged by HIV-1. The modified cells showed resistance to HIV-1 infection. Results indicated that recombinant-adenovirus-modified cells demonstrated good resistance to HIV-1 infection. Modification of HSC-derived immune cells, such as DCs, may be a potent strategy to resist HIV-1 infection.


Subject(s)
Adenoviridae/genetics , Dendritic Cells/virology , Genetic Vectors , HIV-1/pathogenicity , Virus Attachment , Virus Replication , Gene Silencing , HIV Integrase/biosynthesis , HIV Integrase/genetics , Humans , Receptors, CCR5/biosynthesis , Receptors, CCR5/genetics , Receptors, HIV/biosynthesis , Receptors, HIV/genetics , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , pol Gene Products, Human Immunodeficiency Virus/biosynthesis , pol Gene Products, Human Immunodeficiency Virus/genetics
18.
Mol Cell Biochem ; 357(1-2): 255-62, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21638027

ABSTRACT

Insulin-like growth factor-1 (IGF-1) plays the role in cellular lipid synthesis and cell proliferation. However, the role of IGF-1 on the growth of colon cancer cell line HCT-8 is not clear. In this study, HCT-8 cells were exposed to IGF-1 at 0, 10, 50, or 100 ng/ml in serum-free medium. Fatty acid/lipid synthesis in HCT-8 cells was examined by 2-14C-acetate incorporation. HCT-8 cell growth and proliferation were determined by MTT assay and Trypan blue exclusive viable cell counting. We found that in serum starvation conditions, IGF-1 at 10-100 ng/ml induced dose-dependent down regulation of both the ACCα expression and the phosphorylation in HCT-8 cells, maintaining a balance in ACCα activity and lipid synthesis. IGF-1 reduced p-ATM, p-AMPK, and then p-ACCα protein levels in HCT-8 cells. IGF-1 increased p-Akt levels, but decreased p-ERK1/2 levels, leading to the decrease in ACCα protein and mRNA levels. Similarly, ERK1/2 inhibitor PD98059 reduced ACCα expression. IGF-1 influences neither HCT-8 cell growth nor their p53 protein levels and PARP cleavage. In a word, IGF-1 reduced ACCα phosphorylation via an ATM/AMPK signaling pathway and suppressed ACCα expression through an ERK1/2 transduction, playing a dual role in regulating ACCα activity and lipogenesis. This may render a cell with survival advantages under a serum starvation crisis, representing a novel mitogenic role of IGF-1.


Subject(s)
Acetyl-CoA Carboxylase/metabolism , Cell Cycle Proteins/metabolism , Colonic Neoplasms/metabolism , DNA-Binding Proteins/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Insulin-Like Growth Factor I/metabolism , MAP Kinase Signaling System/genetics , Protein Serine-Threonine Kinases/metabolism , Tumor Suppressor Proteins/metabolism , Acetyl-CoA Carboxylase/genetics , Ataxia Telangiectasia Mutated Proteins , Cell Cycle Proteins/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival , Culture Media, Serum-Free , DNA-Binding Proteins/genetics , Fatty Acids/biosynthesis , Flavonoids/pharmacology , Humans , Insulin-Like Growth Factor I/pharmacology , Phosphorylation , Protein Serine-Threonine Kinases/genetics , Signal Transduction/drug effects , Signal Transduction/genetics , Tumor Suppressor Proteins/genetics
19.
Biochem J ; 438(1): 71-80, 2011 Aug 15.
Article in English | MEDLINE | ID: mdl-21585341

ABSTRACT

AKR1B10 (aldo-keto reductase family 1, member B10) protein is primarily expressed in normal human small intestine and colon, but overexpressed in several types of human cancers and considered as a tumour marker. In the present study, we found that AKR1B10 protein is secreted from normal intestinal epithelium and cultured cancer cells, as detected by a newly developed sandwich ELISA and Western blotting. The secretion of AKR1B10 was not affected by the protein-synthesis inhibitor cycloheximide and the classical protein-secretion pathway inhibitor brefeldin A, but was stimulated by temperature, ATP, Ca(2+) and the Ca(2+) carrier ionomycin, lysosomotropic NH(4)Cl, the G-protein activator GTPγS and the G-protein coupling receptor N-formylmethionyl-leucyl-phenylalanine. The ADP-ribosylation factor inhibitor 2-(4-fluorobenzoylamino)-benzoic acid methyl ester and the phospholipase C inhibitor U73122 inhibited the secretion of AKR1B10. In cultured cells, AKR1B10 was present in lysosomes and was secreted with cathepsin D, a lysosomal marker. In the intestine, AKR1B10 was specifically expressed in mature epithelial cells and secreted into the lumen at 188.6-535.7 ng/ml of ileal fluids (mean=298.1 ng/ml, n=11). Taken together, our results demonstrate that AKR1B10 is a new secretory protein belonging to a lysosome-mediated non-classical protein-secretion pathway and is a potential serum marker.


Subject(s)
Adenocarcinoma/metabolism , Aldehyde Reductase/metabolism , Breast Neoplasms/metabolism , Carcinoma, Basal Cell/metabolism , Colorectal Neoplasms/metabolism , Lysosomes/metabolism , Adenosine Triphosphate/pharmacology , Aldo-Keto Reductases , Blotting, Western , Calcium/pharmacology , Culture Media/metabolism , Enzyme-Linked Immunosorbent Assay , Exocytosis , Female , Humans , Immunoenzyme Techniques , Intestines/cytology , Intestines/enzymology , Kidney/cytology , Kidney/enzymology
20.
Biochem Biophys Res Commun ; 403(1): 52-8, 2010 Dec 03.
Article in English | MEDLINE | ID: mdl-21036148

ABSTRACT

OBJECTIVE: To investigate the effect of static pressure on cholesterol accumulation in vascular smooth muscle cells (VSMCs) and its mechanism. METHODS: Rat-derived VSMC cell line A10 treated with 50mg/L ox-LDL and different static pressures (0, 60, 90, 120, 150, 180 mm Hg) in a custom-made pressure incubator for 48 h. Intracellular lipid droplets and lipid levels were assayed by oil red O staining and HPLC; The mRNA levels of caveolin-1 and ABCA1, the protein levels of caveolin-1 SREBP-1 and mature SREBP-1 were respectively detected by RT-PCR or western blot. ALLN, an inhibitor of SREBP metabolism, was used to elevate SREBP-1 protein level in VSMCs treated with static pressure. RESULTS: Static pressures significantly not only increase intracellular lipid droplets in VSMCs, but also elevate cellular lipid content in a pressure-dependent manner. Intracellular free cholesterol (FC), cholesterol ester (CE), total cholesterol (TC) were respectively increased from 60.5 ± 2.8 mg/g, 31.8 ± 0.7 mg/g, 92.3 ± 2.1mg/g at atmosphere pressure (ATM, 0 mm Hg) to 150.8 ± 9.4 mg/g, 235.9 ± 3.0mg/g, 386.7 ± 6.4 mg/g at 180 mm Hg. At the same time, static pressures decrease the mRNA and protein levels of caveolin-1, and induce the activation and nuclear translocation of SREBP-1. ALLN increases the protein level of mature SREBP-1 and decreases caveolin-1 expression, so that cellular lipid levels were upregulated. CONCLUSION: Static pressures stimulate ox-LDL-induced cholesterol accumulation in cultured VSMCs through decreasing caveolin-1 expression via inducing the maturation and nuclear translocation of SREBP-1.


Subject(s)
Caveolin 1/metabolism , Cholesterol/metabolism , Muscle, Smooth, Vascular/metabolism , Sterol Regulatory Element Binding Protein 1/metabolism , Animals , Cells, Cultured , Down-Regulation , Lipoproteins, LDL/pharmacology , Muscle, Smooth, Vascular/drug effects , Pressure , Rats , Sterol Regulatory Element Binding Protein 1/antagonists & inhibitors
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