[Show abstract][Hide abstract] ABSTRACT: High mobility group box 1 (HMGB1) plays important roles in a large variety of diseases; glycyrrhizin (GL) is recognized as an HMGB1 inhibitor. However, few studies have focused on whether glycyrrhizin can potentially improve the outcome of traumatic pancreatitis (TP) by inhibiting HMGB1.
A total of 60 male Wistar rats were randomly divided into three groups (n = 20 in each): Control group, TP group and TP-GL group. Pancreatic trauma was established with a custom-made biological impact machine-III, and GL was administered at 15 minutes after the accomplishment of operation. To determine survival rates during the first 7 days after injury, another 60 rats (n = 20 in each) were grouped and treated as mentioned above. At 24 hours of induction of TP, the histopathological changes in pancreas were evaluated and serum amylase levels were tested. Serum tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and HMGB1 were measured using enzyme linked immunosorbent assay. HMGB1 expressions in pancreas were measured using immunohistochemical staining, Western blot and Real-Time PCR analysis.
Serum levels of HMGB1, TNF-α and IL-6 were increased dramatically in TP group at 24 hours after induction of TP. However, these indicators were reduced significantly by GL administration in TP-GL group comparing with TP group (P<0.05). Meanwhile, survival analysis showed that the seven-day survival rate in TP-GL group was significantly higher than that in TP group (85% versus 65%, P<0.05). GL treatment significantly decreased the pancreatic protein and mRNA expressions of HMGB1 and ameliorated the pancreatic injury in rats with TP.
Glycyrrhizin might play an important role in improving survival rates and ameliorating pancreatic injury of TP by suppression of the expressions of HMGB1 and other proinflammatory cytokine.
PLoS ONE 12/2014; 9(12):e115982. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: FHL1 is an important tumor-suppressor that is downregulated in multiple tumors by unknown mechanisms. We demonstrated that miR-410 specifically targets the 3'UTR of FHL1. Furthermore, using DNA bisulfite modification and sequencing experiments, we demonstrated that the FHL1 promoter is hypermethylated in cancer cells. FHL1 methylation is increased upon miR-410 expression, suggesting that the regulation of FHL1 by miR-410 occurs by a dual mechanism. Using chromatin immunoprecipitation assays, we observed that miR-410 overexpression results in the increased binding of DNMT3A at the FHL1 promoter, which could explain how miR-410 regulates FHL1 methylation. Importantly, in vitro and in vivo results suggest that miR-410 may have oncogenic properties. Furthermore, both miR-410 and DNMT3A are upregulated in clinical human liver and colorectal tumors cancers. Our results suggest that miR-410 may function as an oncomiR and are consistent with its key function in regulating FHL1 in certain digestive system cancers.
PLoS ONE 10/2014; 9(10):e108708. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The activator protein-1 (AP-1) transcription factor complex plays a crucial role in tumor growth and progression. However, how AP-1 transcriptional activity is repressed is not fully understood. Here, we show that RNA-binding protein with multiple splicing 1 (RBPMS1) physically and functionally interacts with AP-1 in vitro and in vivo. The RNA-recognition motif (RRM) and C-terminus of the RBPMS1 isoforms RBPMS1A and RBPMS1C, but not RBPMS1B, interacted with cFos, a member of the AP-1 family that dimerizes with cJun to stimulate AP-1 transcriptional activity. RBPMS1 did not associate with Jun proteins. RBPMS1A and RBPMS1C bound to the basic leucine zipper (bZIP) domain of cFos that mediates dimerization of AP-1 proteins. In addition, RBPMS1A-C interacted with the transcription factor Smad3, which was shown to interact with cJun and increase AP-1 transcriptional activity. RBPMS1 inhibited c-Fos or Smad3-mediated AP-1 transactivation and the expression of AP-1 target genes known to be the key regulators of cancer growth and progression, including vascular endothelial growth factor (VEGF) and cyclin D1. Mechanistically, RBPMS1 blocks the formation of the cFos/cJun or Smad3/cJun complex as well as the recruitment of cFos or Smad3 to the promoters of AP-1 target genes. In cultured cells and a mouse xenograft model, RBPMS1 inhibited the growth and migration of breast cancer cells through c-Fos or Smad3. These data suggest that RBPMS1 is a critical repressor of AP-1 signaling and RBPMS1 activation may be a useful strategy for cancer treatment.
Biochimica et Biophysica Acta (BBA) - Molecular Cell Research 09/2014; · 5.30 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Estrogen receptors ERα and ERβ share considerable sequence homology yet exert opposite effects on breast cancer cell proliferation. While the proliferative role of ERα in breast tumors is well characterized, it is not clear whether the antitumor activity of ERβ can be mobilized in breast cancer cells. Here, we have shown that phosphorylation of a tyrosine residue (Y36) present in ERβ, but not in ERα, dictates ERβ-specific activation of transcription and is required for ERβ-dependent inhibition of cancer cell growth in culture and in murine xenografts. Additionally, the c-ABL tyrosine kinase and EYA2 phosphatase directly and diametrically controlled the phosphorylation status of Y36 and subsequent ERβ function. A nonphosphorylatable, transcriptionally active ERβ mutant retained antitumor activity but circumvented control by upstream regulators. Phosphorylation of Y36 was required for ERβ-mediated coactivator recruitment to ERβ target promoters. In human breast cancer samples, elevated phosphorylation of Y36 in ERβ correlated with high levels of c-ABL but low EYA2 levels. Furthermore, compared with total ERβ, the presence of phosphorylated Y36-specific ERβ was strongly associated with both disease-free and overall survival in patients with stage II and III disease. Together, these data identify a signaling circuitry that regulates ERβ-specific antitumor activity and has potential as both a prognostic tool and a molecular target for cancer therapy.
Journal of Clinical Investigation 06/2014; · 13.77 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Eye absent (Eya) proteins are involved in cell fate determination in a broad spectrum of cells and tissues. Aberrant expression of Eya2 has been documented in a variety of cancers and correlates with clinical outcome. However, whether microRNAs (miRNAs) can regulate Eya2 expression remains unknown. Here, we show that miR-30a represses Eya2 expression by binding to the 3’-untranslated region of Eya2. Overexpression of Eya2 in miR-30a-transfected breast cancer cells effectively rescued the inhibition of cell proliferation and migration caused by miR-30a. Knockdown of Eya2 by small-interfering RNA (siRNA) in breast cancer cells mimicked the effect induced by miR-30a and abolished the ability of miR-30a to regulate breast cancer cell proliferation and migration. The miR-30a/Eya2 axis could regulate G1/S cell cycle progression, accompanied by the modulation of expression of cell cycle-related proteins, including cyclin A, cyclin D1, cyclin E, and c-Myc. Moreover, miR-30a expression was downregulated in breast cancer patients, and negatively correlated with Eya2, which was upregulated in breast cancer patients. These data suggest that the miR-30a/Eya2 axis may play an important role in breast cancer development and progression and that miR-30a activation or Eya2 inhibition may be a useful strategy for cancer treatment.
Biochemical and Biophysical Research Communications 03/2014; · 2.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Annular pancreas (AP) concurrent with pancreaticobiliary maljunction (PBMJ), an unusual coexisted congenital anomaly, often presented symptoms and subjected surgical treatment at the early age of life. We reported the first adult case of concurrent AP with PBMJ presented with symptoms until his twenties, and performed a literature review to analyze the clinicopathological features of such cases comparing with its pediatric counterpart.
The main clinical features of this case were abdominal pain and increased levels of plasma amylase as well as liver function test. A complete type of annular pancreas with duodenal stenosis was found, and dilated common bile duct with high confluence of pancreaticobiliary ducts was also observed. Meanwhile, extremely high levels of bile amylase were detected both in common bile duct and gallbladder. The patient received duodenojejunostomy (side-to-side anastomosis) as well as choledochojejunostomy (Roux-en-Y anastomosis), adnd was discharged in a good condition.
AP concurrent with PBMJ usually presents as duodenal obstruction in infancy, while manifests as pancreatitis in adulthood. Careful long-term follow-up is required for children with AP considering its association with PBMJ which would induce various intractable pathologic conditions in the biliary tract and pancreas.
[Show abstract][Hide abstract] ABSTRACT: Increasing evidence has demonstrated that toll like receptor 4 (TLR4) mediated systemic inflammatory response syndrome (SIRS) accompanied with multiple organ failure, is one of the most common causes of death in patients with severe acute pancreatitis (SAP). Recent reports have revealed that heparan sulfate (HS) proteoglycan, a component of extracellular matrices potentiates the activation of intracellular proinflammatory responses via TLR4, contributing to the aggravation of acute pancreatitis (AP). However, little is known about the participants in the HS/TLR4 mediated inflammatory cascades. Our previous work provided a clue that a membrane potassium channel (MaxiK) is responsible for HS-induced production of inflammatory cytokines. Therefore, in this report we attempted to reveal the roles of MaxiK in the activation of macrophages stimulated by HS. Our results showed that incubation of RAW264.7 cells with HS upregulated MaxiK and TLR4 expression levels. HS could also activate MaxiK channel to promote the efflux of potassium ion from cells, as measured by the elevated activity of caspase-1, whereas it was significantly abolished by the treatment with paxilline, a specific blocker of MaxiK channel. Moreover, it was found that paxilline substantially inhibited HS-induced activation of several different transcription factors in macrophages, including nuclear factor kappaB (NF-κB), p38 and interferon regulatory factor-3 (IRF-3), followed by decreased production of tumor necrosis factor-α (TNF-α) and interferon-β (IFN-β). Taken together, our investigation provides likely evidence that HS/TLR4-mediated intracellular inflammatory cascade depends on the activation of MaxiK, which may offer an important opportunity for a new approach in the therapeutic strategies of SAP. This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Oxidative stress and inflammation play important roles in the progression from simple fatty liver to nonalcoholic steatohepatitis (NASH). The aim of this work was to investigate whether treatment with hydrogen sulfide (H2 S) prevented NASH in rats through abating oxidative stress and suppressing inflammation.
A methionine-choline-deficient (MCD) diet rat model was prepared. Rats were divided into three experimental groups and fed for 8 weeks as follows: (1) control rats; (2) MCD-diet-fed rats; (3) MCD-diet-fed rats treated with NaHS (intraperitoneal injection of 0.1 ml/kg/d of 0.28 mol/l NaHS, a donor of H2 S).
MCD diet impaired hepatic H2 S biosynthesis in rats. Treatment with H2 S prevented MCD-diet-induced NASH, as evidenced by hematoxylin and eosin staining, reduced apoptosis and activities of ALT and AST, and attenuated hepatic fat accumulation in rats. Treatment with H2 S abated MCD-diet-induced oxidative stress through reducing CYP2E1 expression, enhancing HO-1 expression and suppressing mitochondrial ROS formation, and suppressed MCD-diet-induced inflammation through suppressing activated NFκB signaling and reducing IL-6 and TNFα expression. In addition, Treatment of MCD-diet fed rats with H2 S had a beneficial modulation on expression profiles of fatty acid metabolism genes in livers.
Treatment with H2 S prevented NASH induced by MCD diet in rats possibly through abating oxidative stress and suppressing inflammation.
Journal of Gastroenterology and Hepatology 10/2013; · 3.33 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In addition to nuclear estrogen receptor (ER) acting as a transcription factor, extranuclear ER also plays an important role in cancer cell growth regulation through activation of kinase cascades. However, the molecular mechanisms by which extranuclear ER exerts its function are still poorly understood. Here, we report that mediator of ErbB2-driven cell motility (Memo) regulates extranuclear functions of ER. Memo physically and functionally interacted with ER. Through its interaction with the growth factor receptors IGF1R and ErbB2, Memo mediated extranuclear functions of ER, including activation of mitogen-activated protein kinase (MAPK) and protein kinase B/AKT, two important nuclear estrogen receptor growth regulatory protein kinases, and integration of function with nuclear ER. Activation of MAPK and AKT was responsible for Memo modulation of ER phosphorylation and estrogen-responsive gene expression. Moreover, Memo increased anchorage-dependent and -independent growth of ER-positive breast cancer cells in vitro and was required for estrogen-induced breast tumor growth in nude mice. Together, our studies identified Memo as a new component of extranuclear ER signalosome and suggest an essential role for Memo in the regulation of ER-positive breast cancer cell growth.
Journal of Biological Chemistry 07/2013; · 4.60 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Iatrogenic biliary stricture (IBS) is a disastrous complication of cholecystectomy. Although the endoscopic treatments are well accepted as initial attempts for IBS, surgical hepaticojejunostomy (HJ) is often necessary for a considerable proportion of patients. However, the anastomotic stricture after HJ also occurs. METHODS: In the present study, a new procedure, progressive balloon dilation following HJ (HJPBD), was designed and utilized in the IBS treatment. We retrospectively compared HJPBD with the traditional HJ in term of the outcomes when used for IBS treatment. RESULTS: Between January 1997 and December 2009, 112 patients with IBS attributed to cholecystectomy enrolled in our hospital were treated with surgical reconstruction with either HJ (n=58) or HJPBD (n=54). Of the 58 patients in HJ group, 48 patients (82.8%) had a successful outcome, while 52 out of 54 patients (96.3%) in HJPBD group achieved success. The successful surgical reconstruction rates were significantly different between these two groups, with a further improved outcome in patient undergone progressive balloon dilation following HJ. Additionally, 8 of the 10 failure cases in HJ group were successfully rescued by HJPBD procedure. CONCLUSIONS: Our findings suggest that the new procedure of HJPBD could be successfully applied to IBS patients, and significantly improve the outcome of IBS reconstruction.
[Show abstract][Hide abstract] ABSTRACT: MicroRNAs (miRNAs) have been shown to be dysregulated in virus-related cancers; however, miRNA regulation of virus-related cancer development and progression remains poorly understood. Here, we report that miR-148a is repressed by hepatitis B virus (HBV) X protein (HBx) to promote cancer growth and metastasis in a mouse model of hepatocellular carcinoma (HCC). Hematopoietic pre-B cell leukemia transcription factor-interacting protein (HPIP) is an important regulator of cancer cell growth. We used miRNA target prediction programs to identify miR-148a as a regulator of HPIP. Expression of miR-148a in hepatoma cells reduced HPIP expression, leading to repression of AKT and ERK and subsequent inhibition of mTOR through the AKT/ERK/FOXO4/ATF5 pathway. HBx has been shown to play a critical role in the molecular pathogenesis of HBV-related HCC. We found that HBx suppressed p53-mediated activation of miR-148a. Moreover, expression of miR-148a was downregulated in patients with HBV-related liver cancer and negatively correlated with HPIP, which was upregulated in patients with liver cancer. In cultured cells and a mouse xenograft model, miR-148a reduced the growth, epithelial-to-mesenchymal transition, invasion, and metastasis of HBx-expressing hepatocarcinoma cells through inhibition of HPIP-mediated mTOR signaling. Thus, miR-148a activation or HPIP inhibition may be a useful strategy for cancer treatment.
The Journal of clinical investigation 01/2013; · 15.39 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: As it is often difficult for a transplant pathologist to make a definite diagnosis of acute cellular rejection (ACR) by routine morphological analysis of liver allograft biopsy, supplementary methods and objective markers are needed to facilitate this determination. METHODS: To evaluate the diagnostic value of cytotoxic molecules in ACR episodes, immunohistochemical staining for perforin, granzyme B and T-cell intracellular antigen-1 (TIA-1) were performed in liver allograft biopsies. The positive cells in the portal tract area and lobules were counted separately to investigate the distribution of the cytotoxic molecules. RESULTS: The immunohistochemical study showed that the overall positive rates for the three markers were not significantly different between the ACR and non-ACR groups. However, in the portal tract area, perforin-, granzyme B- and TIA-1-positive cells in the ACR group were significantly more than those in the non-ACR groups. In the lobules, perforin- and granzyme B-positive cells in the ACR group were significantly more than those in the biliary complication and opportunistic infection groups, while TIA-1-positive cells was significantly fewer than those in non-ACR groups. The numbers of positive cells in the portal tract area correlated with the rejection activity index of ACR. CONCLUSIONS: These results indicate that, though the overall positive rates have nonsense in ACR diagnosis, the quantification and local distribution analysis of cytotoxic molecule positive cells in liver tissue is helpful for differential diagnosis and severity evaluation of ACR following liver transplantation.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2292255038100487.
[Show abstract][Hide abstract] ABSTRACT: The initiation of breast cancer is associated with increased expression of tumor-promoting estrogen receptor α (ERα) protein and decreased expression of tumor-suppressive ERβ protein. However, the mechanism underlying this process is unknown. Here we show that PES1 (also known as Pescadillo), an estrogen-inducible protein that is overexpressed in breast cancer, can regulate the balance between ERα and ERβ. We found that PES1 modulated many estrogen-responsive genes by enhancing the transcriptional activity of ERα while inhibiting transcriptional activity of ERβ. Consistent with this regulation of ERα and ERβ transcriptional activity, PES1 increased the stability of the ERα protein and decreased that of ERβ through the ubiquitin-proteasome pathway, mediated by the carboxyl terminus of Hsc70-interacting protein (CHIP). Moreover, PES1 transformed normal human mammary epithelial cells and was required for estrogen-induced breast tumor growth in nude mice. Further analysis of clinical samples showed that expression of PES1 correlated positively with ERα expression and negatively with ERβ expression and predicted good clinical outcome in breast cancer. Our data demonstrate that PES1 contributes to breast tumor growth through regulating the balance between ERα and ERβ and may be a better target for the development of drugs that selectively regulate ERα and ERβ activities.
The Journal of clinical investigation 07/2012; 122(8):2857-70. · 15.39 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Recent studies have revealed that the epithelial-mesenchymal transition (EMT) of bile duct epithelial cells is engaged in hepatic fibrogenesis. However, the association between etiological factors of liver disease such as virus or bacterial infection and EMT remains to be investigated. The present study focuses on the inductive role of endotoxin, the main component of the cell wall's ectoblast of gram-negative bacteria, in the EMT of human intrahepatic biliary epithelial cells (HIBEpiCs).
The expressions of E-cadherin, S100A4, α-SMA, TGF-β1, and Smad2/3 in HIBEpiCs cultured with or without lipopolysaccharide LPS, were detected by real-time PCR and Western blotting. We blocked the expression of TGF-β1 using paclitaxel and knocked down Smad2/3 by siRNA to explore the role of TGF-β1/Smad2/3 pathway in the EMT of HIBEpiCs.
Resting HIBEpiCs showed epithelioid cobblestone morphology, and underwent a phenotypic change to produce bipolar cells with a fibroblastic morphology when co-cultured with LPS. After LPS stimulation and the up-regulation of mRNA and protein expression of TGF-β1 and Smad2/Smad3, the mRNA and protein expression of mesenchymal markers (S100A and α-SMA) increased significantly. Paclitaxel inhibited the mRNA and protein expression of TGF-β1 in vitro. Knock-down of Smad2/3 by siRNA led to up-regulation of epithelial markers E-cadherin and down-regulation of S100A and α-SMA, indicating a reversal of the EMT.
LPS can induce the expression of TGF-ß1 and a subsequent EMT in HIBEpiCs, and the inhibition of TGF-ß1 or Smad 2/3 could reverse this EMT, suggesting that LPS may play a potential role in the EMT of HIBEpiCs.
Journal of Surgical Research 12/2011; 171(2):819-25. · 2.12 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Nonanastomotic biliary strictures represent a serious complication after orthotopic liver transplantation (OLT). This study investigates the potential role of mucins in bile duct injury after OLT.
Sprague-Dawley rats were divided into four groups: normal group (Normal, n=5), sham-operated group (Sham, n=20), OLT group with 1 hr donor cold ischemic time (n=20), and OLT group with 12 hr donor cold ischemic time (OLTn=20). Expression of mucins and GATA factors in bile ducts was examined by real-time polymerase chain reaction, immunohistochemistry, and immunoblotting. Bile was collected for biochemical analysis, and the histological changes associated with bile duct injury were evaluated.
In normal bile ducts, Muc1, Muc2, Muc3A, Muc4, and Muc6 mRNA were expressed, whereas Muc5AC mRNA was undetectable. The expression of Muc1, Muc3A, and Muc4 but not Muc2 and Muc6 at mRNA level in graft bile ducts decreased remarkably early after OLT. The decreased expression of Muc1 and Muc4 was further confirmed at protein level by immunohistochemistry and immunoblotting. Downregulation of Muc1 and Muc3A expression by prolonged cold ischemic time was significantly associated with the injury severity scores of large but not small bile ducts. Among six GATA factors, GATA3, GATA4, and GATA6 mRNA were expressed in normal bile ducts. GATA4 and GATA6 mRNA levels decreased significantly after OLT.
Downregulation of Muc1 and Muc3A expression by prolonged cold ischemic time may play a potential role in large bile duct injury early after OLT.
[Show abstract][Hide abstract] ABSTRACT: To investigate whether progesterone receptor B (PRB) can be sumoylated by SUMO-2/3 and the effect of sumoylation on PRB transcriptional activity.
SUMO-2/3 cDNA was amplified from MCF-7 cDNA and cloned into the eukaryotic expression vector pcDNA3-FLAG. The plasmid pXJ40-myc-PRB was cotransfected with pcDNA3FLAG-SUMO2, pcDNA3FLAG-SUMO3 or the mock control into 293T cells, and PRB sumoylation was detected by immunoprecipitation and Western blotting. The effect of PRB sumoylation on its transcriptional activity was determined using reporter luciferase assay.
pcDNA3FLAG-SUMO2 and pcDNA3FLAG-SUMO3 vectors were successfully constructed. SUMO-2/3 could bind covalently to PRB and increase its transcriptional dependent on the presence of progesterone.
PRB can be sumoylated by SUMO-2/3 and its function is regulated by this modification.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 09/2011; 31(9):1493-7.
[Show abstract][Hide abstract] ABSTRACT: Four and a half LIM domain (FHL) protein 3 is a member of the FHL protein family that plays roles in the regulation of signal transduction, cell adhesion, survival, and mobility. FHL3 has been implicated in the development and progression of liver cancer. However, the biological function of FHL3 in other cancers remains unclear. Here, we show that FHL3 is downregulated in breast cancer patients. Using small interfering RNA (siRNA) knockdown and/or overexpression experiments, we demonstrated that FHL3 suppressed anchorage-dependent and -independent growth of human breast cancer cells. The antiproliferative effects of FHL3 on breast cancer cell growth were associated with both the G1 and the G2/M cell cycle arrest, which was accompanied by a marked inhibition of the G1-phase marker cyclin D1 and the G2/M-phase marker cyclin B1 as well as the induction of the cyclin dependent kinase inhibitor p21 (WAF1/CIP1), a negative regulator of cell cycle progression at G1 and G2. These results suggest that FHL3 may play a role in the development and progression of breast cancer, and thereby may be a potential target for human breast cancer gene therapy.
International Union of Biochemistry and Molecular Biology Life 09/2011; 63(9):764-71. · 2.79 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Four and a half Lin-11, Isl-1, Mac-3 (LIM) protein 1 (FHL1) has been linked to carcinogenesis. However, the role of FHL1 in lung cancer remains unclear and the detailed mechanism underlying its tumor suppressive role is poorly understood. The purpose of this study was to examine FHL1 expression in lung cancer patients and to investigate how it was associated with lung cancer cell growth. Immunoblotting and immunohistochemistry showed that FHL1 protein was downregulated in over 90% of 80 lung cancer patients. FHL1 expression was strongly correlated with tumor histological types (p < 10(-4) ) and the differentiation of the tumor (p = 0.002). FHL1 inhibited anchorage-dependent and -independent growth of human lung cancer cell lines. The inhibitory effects of FHL1 on lung cancer cell growth were associated with both the G1 and the G2/M cell cycle arrest concomitant with a marked inhibition of cyclin A, cyclin B1 and cyclin D as well as the induction of the cyclin dependent kinase inhibitors p21 (WAF1/CIP1) and p27 (Kip1). Direct intratumoral injection of an adenovirus expressing FHL1 dramatically suppressed the growth of A549 lung cancer cells in nude mice. Our data suggest that reduced expression of FHL1 may play an important role in the development and progression of lung cancer and that FHL1 may be a useful target for lung cancer gene therapy.
International Journal of Cancer 06/2011; 130(11):2549-56. · 6.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Secreted growth factors have been shown to stimulate the transcriptional activity of estrogen receptors (ER) that are responsible for many biological processes. However, whether these growth factors physically interact with ER remains unclear. Here, we show for the first time that connective tissue growth factor (CTGF) physically and functionally associates with ER. CTGF interacted with ER both in vitro and in vivo. CTGF interacted with ER DNA-binding domain. ER interaction region in CTGF was mapped to the thrombospondin type I repeat, a cell attachment motif. Overexpression of CTGF inhibited ER transcriptional activity as well as the expression of estrogen-responsive genes, including pS2 and cathepsin D. Reduction of endogenous CTGF with CTGF small interfering RNA enhanced ER transcriptional activity. The interaction between CTGF and ER is required for the repression of estrogen-responsive transcription by CTGF. Moreover, CTGF reduced ER protein expression, whereas the CTGF mutant that did not repress ER transcriptional activity also did not alter ER protein levels. The results suggested the transcriptional regulation of estrogen signaling through interaction between CTGF and ER, and thus may provide a novel mechanism by which cross-talk between secreted growth factor and ER signaling pathways occurs.
PLoS ONE 05/2011; 6(5):e20028. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To construct a vector of ErbB2 small interfering RNA(siRNA), and to investigate its effect on ErbB2 expression and the growth of ZR75-1 breast cancer cells.
Two ErbB2-siRNAs were designed and inserted into the pSliencer 2.1-U6 neo vector. After confirmed by restriction and DNA sequencing, siRNA vectors were co-transfected with the FLAG-ErbB2 expression vector into human embryonic kidney 293T cells, or transfected into SKBR3 and ZR75-1 breast cancer cells. The effects of siRNAs on the expression of ErbB2 were identified by Western blot and the proliferation of ZR75-1 cells was repressed.
Two siRNAs could effectively inhibit the expression of exogenous and endogenous ErbB2 proteins, and could repress the growth of ZR75-1 cells.
ErbB2 siRNAs effectively inhibit the expression of ErbB2, thus repressing the growth of ZR75-1 cells.
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 03/2011; 27(3):257-9.