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European cells & materials  2014;28:223-235.
Despite extensive research in knee and hip osteoarthritis (OA), the underlying mechanism of temporomandibular joint (TMJ) disorder remains largely unknown. The purpose of this study was to determine whether the constitutive activation of β-catenin in the middle and deep layers of the articular cartilage can compromise the homeostasis of this tissue in the TMJ. Co12CreERT2 transgenic mice were bred with RosamT/mG reporter mice to determine Cre recombination efficiency. Co12CreERT2 mice were then crossed with β-cateninflox (ex3)/+ mice to generate β-catenin conditional activation mice, β-catenin(ex3)Co12ER. TMJ samples were harvested when the mice were 1-, 3- or 6-month-old and evaluated using histology, histomorphometry and immunohistochemistry. β-catenin(ex3)Co12ER mice were further crossed with Mmp13flox/flox and Adamts5−/− mice to generate β-catenin(ex3)/Mmp13)Co12ER and β-catenin(ex3)Co12ER)/Adamts5−/− double mutant mice to investigate the role of Mmp13 and Adamts5 in the development of TMJ disorder. High levels of Cre-recombination were seen in Co12CreERT2;RosamT/mG mice. Progressive TMJ defects developed in 1-, 3- and 6-month-old β-catenin(ex3)Co12ER mice, as revealed by histology and histomorphometry. Results further demonstrated that the defects observed in β-catenin(ex3)Co12ER mice were significantly decelerated after deletion of the Mmp13 or Adamts5 gene in (β-catenin(ex3)/Mmp13)co12ER or β-catenin(ex3)Co12ER/ Adamts5−/− double mutant mice. In summary, we found that β-catenin is a critical gene in the induction of TMJ cartilage degeneration, and over-expressing β-catenin in TMJ cartilage leads to defects assembling an OA-like phenotype. Deletion of Mmp13 and Adamts5 in β-catenin(ex3)Co12ER mice ameliorates the development of TMJ defects. This study suggests that Mmp13 and Adamts5 could be potential therapeutic targets for the treatment of TMJ disorders.
PMCID: PMC4288590  PMID: 25340802
Temporomandibular joint; osteoarthritis; β-catenin; MMP13; Adamts5
2.  Modification of perpendicular magnetic anisotropy and domain wall velocity in Pt/Co/Pt by voltage-induced strain 
Scientific Reports  2015;5:7921.
The perpendicular magnetic anisotropy Keff, magnetization reversal, and field-driven domain wall velocity in the creep regime are modified in Pt/Co(0.85–1.0 nm)/Pt thin films by strain applied via piezoelectric transducers. Keff, measured by the extraordinary Hall effect, is reduced by 10 kJ/m3 by tensile strain out-of-plane εz = 9 × 10−4, independently of the film thickness, indicating a dominant volume contribution to the magnetostriction. The same strain reduces the coercive field by 2–4 Oe, and increases the domain wall velocity measured by wide-field Kerr microscopy by 30-100%, with larger changes observed for thicker Co layers. We consider how strain-induced changes in the perpendicular magnetic anisotropy can modify the coercive field and domain wall velocity.
PMCID: PMC4300497  PMID: 25605499
3.  An anti-leishmanial thiadiazine agent induces multiple myeloma cell apoptosis by suppressing the nuclear factor kappaB signalling pathway 
Chen, G | Han, K | Xu, X | Du, X | Zhang, Z | Tang, J | Shi, M | Wang, M | Li, J | Cao, B | Mao, X
British Journal of Cancer  2013;110(1):63-70.
Nuclear factor κB (NFκB) has a critical role in the pathophysiology of multiple myeloma. Targeting NFκB is an important strategy for anti-myeloma drug discovery.
Luciferase assay was used to evaluate the effects of DETT on NFκB activity. Annexin V–PI double staining and immunoblotting were used to evaluate DETT-induced cell apoptosis and suppression of NFκB signalling. Anti-myeloma activity was studied in nude mice.
DETT downregulated IKKα, β, p65, and p50 expression and inhibited phosphorylation of p65 (Ser536) and IκBα. Simultaneously, DETT increased IκBα, an inhibitor of the p65/p50 heterodimer, even in the presence of stimulants lipopolysaccharide, tumour necrosis factor-α, or interleukin-6. DETT inhibited NFκB transcription activity and downregulated NFκB-targeted genes, including Bcl-2, Bcl-XL, and XIAP as measured by their protein expression. Deregulation of NFκB signalling by DETT resulted in MM cell apoptosis characterised by cleavage of caspase-3, caspase-8, and PARP. Notably, this apoptosis was partly blocked by the activation of NFκB signalling in the presence of TNFα and IL-6. Moreover, DETT delayed myeloma tumour growth in nude mice without overt toxicity.
DETT displays a promising potential for MM therapy as an inhibitor of the NFκB signalling pathway.
PMCID: PMC3887303  PMID: 24231956
3,5-diethyl-1,3,5-thiadiazinane-2-thione (DETT); NFκB; multiple myeloma; apoptosis
4.  Cognitive changes preceding clinical symptom onset of mild cognitive impairment and relationship to ApoE genotype 
Current Alzheimer research  2014;11(8):773-784.
This study had two goals (1) to evaluate changes in neuropsychological performance among cognitively normal individuals that might precede the onset of clinical symptoms, and (2) to examine the impact of Apolipoprotein E (ApoE) genotype on these changes.
Longitudinal neuropsychological, clinical assessments and consensus diagnoses were completed prospectively in 268 cognitively normal individuals. The mean duration of follow-up was 9.2 years (+/− 3.3). 208 participants remained normal and 60 developed cognitive decline, consistent with a diagnosis of MCI or dementia. Cox regression analyses were completed, for both baseline scores and rate of change in scores, in relation to time to onset of clinical symptoms. Analyses were completed both with and without ApoE-4 status included. Interactions with ApoE-4 status were also examined.
Lower baseline test scores, as well as greater rate of change in test scores, were associated with time to onset of clinical symptoms (p<0.001). The mean time from baseline to onset of clinical symptoms was 6.15 (+/− 3.4) years. The presence of an ApoE-4 allele doubled the risk of progression. The rate of change in two of the test scores was significantly different in ApoE-4 carriers vs. non-carriers.
Cognitive performance declines prior to the onset of clinical symptoms that are a harbinger of a diagnosis of MCI. Cognitive changes in normal individuals who will subsequently decline may be observed at least 6.5 years prior to symptom onset. In addition, the risk of decline is doubled among individuals with an ApoE-4 allele.
PMCID: PMC4163954  PMID: 25212916
preclinical Alzheimer's disease; cognitive decline; Apolipoprotein E genotype; mild cognitive impairment; episodic memory; longitudinal follow-up
5.  Direct targeting of SUZ12/ROCK2 by miR-200b/c inhibits cholangiocarcinoma tumourigenesis and metastasis 
Peng, F | Jiang, J | Yu, Y | Tian, R | Guo, X | Li, X | Shen, M | Xu, M | Zhu, F | Shi, C | Hu, J | Wang, M | Qin, R
British Journal of Cancer  2013;109(12):3092-3104.
The multidrug resistance and distant metastasis of cholangiocarcinoma result in high postoperative recurrence and low long-term survival rates. It has been demonstrated that the ectopic expression of miR-200 suppresses the multidrug resistance and metastasis of cancer. However, the expression and function of miR-200 in cholangiocarcinoma has not yet been described.
In this study, we identified dysregulated microRNAs (miRNAs, miR) in cholangiocarcinoma tissue by microarray analysis, and subsequent real-time PCR and northern blot analyses validated the expression of candidate miR. We performed functional analyses and investigated the relationship between miR-200b/c expression and the properties of cholangiocarcinoma cells. A dual luciferase assay was applied to examine the effect of miRNAs on the 3′-UTR of target genes, and we demonstrated the function of the target gene by siRNA transfection identifying the downstream pathway via western blotting.
We found significantly downregulated expression of four miR-200 family members (miR-200a/b/c/429) and then confirmed that ectopic miR-200b/200c inhibits the migration and invasion of cholangiocarcinoma cells both in vitro and in vivo. We found that miR-200b/c influenced the tumourigenesis of cholangiocarcinoma cells including their tumour-initiating capacity, sphere formation, and drug resistance. We further found that miR-200b/c regulated migration and invasion capacities by directly targeting rho-kinase 2 and regulated tumorigenic properties by directly targeting SUZ12 (a subunit of a polycomb repressor complex).
Our study shows that miR-200b/c has a critical role in the regulation of the tumorigenic and metastatic capacity of cholangiocarcinoma and reveals the probable underlying mechanisms.
PMCID: PMC3859942  PMID: 24169343
cholangiocarcinoma; microRNA; tumourigenesis; metastasis
6.  Role of hepcidin in murine brain iron metabolism 
Brain iron homeostasis is maintained by a balance of both iron uptake and release, and accumulating evidence has revealed that brain iron concentrations increase with aging. Hepcidin, an iron regulatory hormone produced by hepatocytes in response to inflammatory stimuli, iron, and hypoxia, has been shown to be the long-sought hormone responsible for the regulation of body iron balance and recycling in mammals. In this study, we report that hepcidin is widely expressed in the murine brain. In cerebral cortex, hippocampus and striatum, hepcidin mRNA levels increased with aging. Injection of hepcidin into the lateral cerebral ventricle resulted in decreased Fpn1 protein levels in cerebral cortex, hippocampus, and striatum. Additionally, treatment of primary cultured neurons with hepcidin caused decreased neuronal iron release and Fpn1 protein levels. Together, our data provide further evidence that hepcidin may be involved in the regulation of brain iron metabolism.
PMCID: PMC4225129  PMID: 19898775
Hepcidin; Ferroportin1; Brain iron metabolism; Aging; Murine
7.  Imaging molecular adsorption and desorption dynamics on graphene using terahertz emission spectroscopy 
Scientific Reports  2014;4:6046.
Being an atomically thin material, graphene is known to be extremely susceptible to its environment, including defects and phonons in the substrate on which it is placed as well as gas molecules that surround it. Thus, any device design using graphene has to take into consideration all surrounding components, and device performance needs to be evaluated in terms of environmental influence. However, no methods have been established to date to readily measure the density and distribution of external perturbations in a quantitative and non-destructive manner. Here, we present a rapid and non-contact method for visualizing the distribution of molecular adsorbates on graphene semi-quantitatively using terahertz time-domain spectroscopy and imaging. We found that the waveform of terahertz bursts emitted from graphene-coated InP sensitively changes with the type of atmospheric gas, laser irradiation time, and ultraviolet light illumination. The terahertz waveform change is explained through band structure modifications in the InP surface depletion layer due to the presence of localized electric dipoles induced by adsorbed oxygen. These results demonstrate that terahertz emission serves as a local probe for monitoring adsorption and desorption processes on graphene films and devices, suggesting a novel two-dimensional sensor for detecting local chemical reactions.
PMCID: PMC4131213  PMID: 25116593
8.  Reducing dietary loading decreases mouse temporomandibular joint degradation induced by anterior crossbite prosthesis 
Dietary loading has been reported to have an effect on temporomandibular joint (TMJ) remodeling via periodontal-muscular reflex. We therefore examined whether reducing dietary loading decreased TMJ degradation induced by the unilateral anterior crossbite prosthesis as we recently reported.
Forty 6-week-old female C57BL/6J mice were randomly divided into two experimental and two control groups. One experimental and one control group received small-size diet and the other two groups received large-size diet. Unilateral anterior crossbite prosthesis was created in the two experimental groups. The TMJ samples were collected 3 weeks after experimental operation. Histological changes in condylar cartilage and subchondral bone were assessed by Hematoxylin & Eosin, toluidine blue, Safranin O and tartrate-resistant acid phosphatase staining. Real-time polymerase chain reaction (PCR) and/or immunohistochemistry were performed to evaluate the expression levels of Collagen II, Aggrecan, a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5) and RANKL/RANK/OPG in TMJ condylar cartilage and/or subchondral bone.
Thinner and degraded cartilage, reduced cartilage cellular density, decreased expression levels of Collagen II and Aggrecan, loss of subchondral bone and enhanced osteoclast activity were observed in TMJs of both experimental groups. However, the cartilage degradation phenotype was less severe and cartilage ADAMTS-5 mRNA was lower while OPG/RANKL ratio in cartilage and subchondral bone was higher in the small-size than large-size diet experimental group. No differences of histomorphology and the tested molecules were found between the two control groups.
The current findings suggest that a lower level of functional loading by providing small-size diet could reduce TMJ degradation induced by the biomechanical stimulation from abnormal occlusion.
PMCID: PMC4111231  PMID: 24316289
Temporomandibular joint; Dental occlusion; Dietary loading; Osteoarthritis; Cartilage; Subchondral bone
9.  Phase II trial of high-dose topotecan, melphalan and CY with autologous stem cell support for multiple myeloma 
Bone marrow transplantation  2010;46(4):510-515.
In spite of high-dose chemotherapy followed by autologous hematopoietic SCT multiple myeloma (MM) eventually recurs, highlighting the need for more effective treatment approaches. Patients received topotecan 3.5 mg/m2 intravenously on days −6 to −2, melphalan 70 mg/m2 intravenously on days −3 and −2 and CY 1 g/m2 intravenously on days −6, −5 and −4. Overall response rate (ORR) consisting of complete response and partial response (CR + PR, PFS, OS and toxicity are reported. Between August 2002 to March 2004, 60 patients (34 men and 26 women) with a median age of 61 years (range 45–72) were enrolled. Forty-one patients were treated for consolidation of first remission, while 19 patients had relapsed/refractory disease. ORR was 85% (CR 12%, very good PR 43% and PR 30%). Median time to neutrophil (ANC>0.5 × 109/L) and plt engraftment (>20 × 109/L) was 10 (range 7–12 days) and 9 days (range 6–79 days), respectively. A majority of the common adverse events were grade 1–3 mucositis/stomatitis (65%), grade 1 or 2 nausea (59%) and grade 1 or 2 diarrhea (41%). Median PFS was 18.5 months and median OS has yet not been reached. In conclusion, topotecan, melphalan and CY is a safe and active conditioning regimen for auto hematopoietic SCT in MM. The ORR and PFS were comparable to high-dose melphalan.
PMCID: PMC4080410  PMID: 20581887
topotecan; melphalan; CY; multiple myeloma; autologous stem cell transplant
10.  InPBi Single Crystals Grown by Molecular Beam Epitaxy 
Scientific Reports  2014;4:5449.
InPBi was predicted to be the most robust infrared optoelectronic material but also the most difficult to synthesize within In-VBi (V = P, As and Sb) 25 years ago. We report the first successful growth of InPBi single crystals with Bi concentration far beyond the doping level by gas source molecular beam epitaxy. The InPBi thin films reveal excellent surface, structural and optical qualities making it a promising new III–V compound family member for heterostructures. The Bi concentration is found to be 2.4 ± 0.4% with 94 ± 5% Bi atoms at substitutional sites. Optical absorption indicates a band gap of 1.23 eV at room temperature while photoluminescence shows unexpectedly strong and broad light emission at 1.4–2.7 μm which can't be explained by the existing theory.
PMCID: PMC4071318  PMID: 24965260
11.  Four pairs of gene–gene interactions associated with increased risk for type 2 diabetes (CDKN2BAS–KCNJ11), obesity (SLC2A9–IGF2BP2, FTO–APOA5), and hypertension (MC4R–IGF2BP2) in Chinese women 
Meta Gene  2014;2:384-391.
Metabolic disorders including type 2 diabetes, obesity and hypertension have growing prevalence globally every year. Genome-wide association studies have successfully identified many genetic markers associated to these diseases, but few studied their interaction effects. In this study, twenty candidate SNPs from sixteen genes are selected, and a lasso-multiple regression approach is implemented to consider the SNP–SNP interactions among them in an Asian population. It is found out that the main effects of the markers are weak but the interactions among the candidates showed a significant association to diseases. SNPs from genes CDKN2BAS and KCNJ11 are significantly associated to risk for developing diabetes, and SNPs from FTO and APOA5 might interact to play an important role for the onset of hypertension.
PMCID: PMC4287808  PMID: 25606423
Metabolic disorder; Candidate genes; Interaction effects
12.  Non-viral FoxM1 gene delivery to hepatocytes enhances liver repopulation 
Cell Death & Disease  2014;5(5):e1252-.
Hepatocyte transplantation as a substitute strategy of orthotopic liver transplantation is being studied for treating end-stage liver diseases. Several technical hurdles must be overcome in order to achieve the therapeutic liver repopulation, such as the problem of insufficient expansion of the transplanted hepatocytes in recipient livers. In this study, we analyzed the application of FoxM1, a cell-cycle regulator, to enhance the proliferation capacity of hepatocytes. The non-viral sleeping beauty (SB) transposon vector carrying FoxM1 gene was constructed for delivering FoxM1 into the hepatocytes. The proliferation capacities of hepatocytes with FoxM1 expression were examined both in vivo and in vitro. Results indicated that the hepatocytes with FoxM1 expression had a higher proliferation rate than wild-type (WT) hepatocytes in vitro. In comparison with WT hepatocytes, the hepatocytes with FoxM1 expression had an enhanced level of liver repopulation in the recipient livers at both sub-acute injury (fumaryl acetoacetate hydrolase (Fah)–/– mice model) and acute injury (2/3 partial hepatectomy mice model). Importantly, there was no increased risk of tumorigenicity with FoxM1 expression in recipients even after serial transplantation. In conclusion, expression of FoxM1 in hepatocytes enhanced the capacity of liver repopulation without inducing tumorigenesis. FoxM1 gene delivered by non-viral SB vector into hepatocytes may be a viable approach to promote therapeutic repopulation after hepatocyte transplantation.
PMCID: PMC4047909  PMID: 24853430
FoxM1; sleeping beauty transposon; non-viral; hepatocyte transplantation; liver repopulation
13.  Elf3 drives β-catenin transactivation and associates with poor prognosis in colorectal cancer 
Cell Death & Disease  2014;5(5):e1263-.
Aberrant regulation of the Wnt/β-catenin pathway plays important roles in colorectal carcinogenesis, with over 90% of cases of sporadic colon cancer featuring β-catenin accumulation. While ubiquitination-mediated degradation is widely accepted as a major route for β-catenin protein turnover, little is known about the regulation of β-catenin in transcriptional level. Here we show that Elf3, a member of the E-twenty-six family of transcription factors, drives β-catenin transactivation and associates with poor survival of colorectal cancer (CRC) patients. We first found recurrent amplification and upregulation of Elf3 in CRC tissues, and further Gene Set Enrichment Analysis identified significant association between Elf3 expression and activity of WNT/β-catenin pathway. Chromatin immunoprecipitation and electrophoretic mobility shift assay consistently revealed that Elf3 binds to and transactivates β-catenin promoter. Ectopic expression of Elf3 induces accumulation of β-catenin in both nucleus and cytoplasm, causing subsequent upregulation of several effector genes including c-Myc, VEGF, CCND1, MMP-7 and c-Jun. Suppressing Elf3 in CRC cells attenuates β-catenin signaling and decreases cell proliferation, migration and survival. Targeting Elf3 in xenograft tumors suppressed tumor progression in vivo. Taken together, our data identify Elf3 as a pivotal driver for β-catenin signaling in CRC, and highlight potential prognostic and therapeutic significance of Elf3 in CRC.
PMCID: PMC4047871  PMID: 24874735
Elf3; β-catenin; transactivation; colorectal cancer; prognosis
14.  A novel semiconductor compatible path for nano-graphene synthesis using CBr4 precursor and Ga catalyst 
Scientific Reports  2014;4:4653.
We propose a novel semiconductor compatible path for nano-graphene synthesis using precursors containing C-Br bonding and liquid catalyst. The unique combination of CBr4 as precursor and Ga as catalyst leads to efficient C precipitation at a synthesis temperature of 200°C or lower. The non-wetting nature of liquid Ga on tested substrates limits nano-scale graphene to form on Ga droplets and substrate surfaces at low synthesis temperatures of T ≤ 450°C and at droplet/substrate interfaces by C diffusion via droplet edges when T ≥ 400°C. Good quality interface nano-graphene is demonstrated and the quality can be further improved by optimization of synthesis conditions and proper selection of substrate type and orientation. The proposed method provides a scalable and transfer-free route to synthesize graphene/semiconductor heterostructures, graphene quantum dots as well as patterned graphene nano-structures at a medium temperature range of 400–700°C suitable for most important elementary and compound semiconductors.
PMCID: PMC3983675  PMID: 24722194
Biology of Sport  2014;31(1):69-72.
The beneficial effect of magnesium supplementation on exercise performance has been reported by many researchers. In the present study, the effect of nigari, a concentrate of deep seawater containing high magnesium levels, on exercise performance, was examined. Gerbils were given double-distilled water or nigari (18 mg · kg−1, po) orally 30 min before exercise. All animals were subjected to forced exercise on a treadmill for 90 min at three successive speeds of 10, 15, and 20 m · min−1. The retention numbers were recorded. The retention numbers were 85.0 ± 21.0, 46.0 ± 9.7, and 48.0 ± 14.2 in the control group, and 44.0 ± 10.9, 23.0 ± 8.4, and 13.0 ± 4.8 in the nigari-treated group at the three speeds, respectively. The retention numbers were significantly reduced at higher speeds (by 50% at 15 and 73% at 20 m · min−1, respectively) in the nigari-treated group when compared to those of the control group, respectively. Thus, nigari administration appeared to reduce retention numbers and enhance exercise performance in gerbils.
PMCID: PMC3994588  PMID: 24917692
Nigari; concentrated deep seawater; Mg2+; retention number; treadmill exercise
16.  Clinical efficacy of a medically supervised outpatient high-protein, low-calorie diet program is equivalent in prediabetic, diabetic and normoglycemic obese patients 
Nutrition & Diabetes  2014;4(2):e105-.
Type 2 diabetes mellitus (T2DM) affects approximately 10% of Americans, while 79 million Americans are estimated to have glucose intolerance or prediabetes (pre-DM). The present study was designed to determine whether obese patients with pre-DM or T2DM would lose weight as effectively as obese normoglycemic patients, in a medically supervised high-protein, low-calorie-weight management program.
Patients enrolled in a self-paid, university-based, outpatient weight loss program using prescribed very-low-calorie diet (VLCD) (500–800 cal per day) or LCD diet (800–1200 cal per day), recommended exercise and group behavioral counseling were studied retrospectively. Patients entering the program for the first time and attending weekly clinic visits for more than 4 weeks were included in the analysis.
A total of 2093 obese patients, of whom 583 patients with pre-DM (fasting glucose ⩾100 and <126 mg dl−1), 367 patients with T2DM and 1143 normoglycemic patients entered the program from 1991 to 2010, who met all the inclusion criteria were included in the analysis. The body weight at baseline was 104.0±20.0 kg for DM, 101.4±18.4 for pre-DM and 99.0±18.8 kg for non-DM. Weight loss and percent of weight loss within 12 months were analyzed using a linear mixed-effects model. There was no significant difference in weight loss between DM vs non-DM (P=0.4597) and pre-DM vs non-DM (P=0.6006) in 12 months. The length of enrollment in the program was positively correlated to weight loss rates in all patients (P<0.001).
This study demonstrates that obese, pre-DM and DM patients all lost weight as effectively with VLCD or LCD over 12 months. Given the impact of weight loss on the progression of comorbid conditions, these data support the hypothesis that medically supervised diets, including VLCD and LCD, should be more widely used in the prevention and treatment of obese patients with pre-DM or T2DM.
PMCID: PMC3940825  PMID: 24513578
VLCD; diabetes mellitus; weight loss; obesity; prediabetes
17.  Tumor suppressor NDRG2 tips the balance of oncogenic TGF-β via EMT inhibition in colorectal cancer 
Shen, L | Qu, X | Ma, Y | Zheng, J | Chu, D | Liu, B | Li, X | Wang, M | Xu, C | Liu, N | Yao, L | Zhang, J
Oncogenesis  2014;3(2):e86-.
Transforming growth factor-beta (TGF-β), a pluripotent cytokine expressed in the colon, has a crucial but paradoxical role in colorectal cancer (CRC). TGF-β is a potent proliferation inhibitor of normal colon epithelial cells and acts as a tumor suppressor. However, TGF-β also promotes invasion and metastasis during late-stage CRC, thereby acting as an oncogene. Thus, understanding the factors behind the paradoxical roles of TGF-β and elucidating the mechanisms by which TGF-β-induced proliferation inhibition is impaired in CRC are necessary. Here, we found that the N-Myc tumor suppressor gene downstream-regulated gene NDRG2 (N-Myc downstream-regulated gene 2), which is a TGF-β-responsive gene, abrogated TGF-β-induced epithelial–mesenchymal transition (EMT) and further inhibited the invasion and migration of CRC cells. TGF-β positively induced NDRG2 expression through direct transactivation mediated by Sp1 and by abrogation of the repressive c-Myc/Miz-1 complex on NDRG2 promoter in normal epithelial cells. Aberrant hypermethylation of NDRG2, which could respond to TGF-β growth inhibition signaling, abrogated the inhibitory effect of NDRG2 in TGF-β-induced EMT in CRCs. Reduced NDRG2 expression was highly correlated with the invasion stage and metastasis of CRC. Our study establishes that NDRG2 is a new tumor suppressor gene that responds to TGF-β anti-proliferative signaling and tips the balance of oncogenic TGF-β during late-stage CRC.
PMCID: PMC3940918  PMID: 24492480
colorectal cancer; TGF-β; NDRG2; EMT; methylation
18.  TXNL1-XRCC1 pathway regulates cisplatin-induced cell death and contributes to resistance in human gastric cancer 
Xu, W | Wang, S | Chen, Q | Zhang, Y | Ni, P | Wu, X | Zhang, J | Qiang, F | Li, A | Røe, O D | Xu, S | Wang, M | Zhang, R | Zhou, J
Cell Death & Disease  2014;5(2):e1055-.
Cisplatin is a cytotoxic platinum compound that triggers DNA crosslinking induced cell death, and is one of the reference drugs used in the treatment of several types of human cancers including gastric cancer. However, intrinsic or acquired drug resistance to cisplatin is very common, and leading to treatment failure. We have recently shown that reduced expression of base excision repair protein XRCC1 (X-ray repair cross complementing group1) in gastric cancerous tissues correlates with a significant survival benefit from adjuvant first-line platinum-based chemotherapy. In this study, we demonstrated the role of XRCC1 in repair of cisplatin-induced DNA lesions and acquired cisplatin resistance in gastric cancer by using cisplatin-sensitive gastric cancer cell lines BGC823 and the cisplatin-resistant gastric cancer cell lines BGC823/cis-diamminedichloridoplatinum(II) (DDP). Our results indicated that the protein expression of XRCC1 was significantly increased in cisplatin-resistant cells and independently contributed to cisplatin resistance. Irinotecan, another chemotherapeutic agent to induce DNA damaging used to treat patients with advanced gastric cancer that progressed on cisplatin, was found to inhibit the expression of XRCC1 effectively, and leading to an increase in the sensitivity of resistant cells to cisplatin. Our proteomic studies further identified a cofactor of 26S proteasome, the thioredoxin-like protein 1 (TXNL1) that downregulated XRCC1 in BGC823/DDP cells via the ubiquitin-proteasome pathway. In conclusion, the TXNL1-XRCC1 is a novel regulatory pathway that has an independent role in cisplatin resistance, indicating a putative drug target for reversing cisplatin resistance in gastric cancer.
PMCID: PMC3944244  PMID: 24525731
cisplatin; gastric cancer; drug resistance; XRCC1; TXNL1
19.  Decacationic [70]Fullerene Approach for Efficient Photokilling of Infectious Bacteria and Cancer Cells 
ECS transactions  2013;45(20):10.1149/04520.0065ecst.
Photodynamic inactivation of pathogenic bacteria and cancer cells by novel water-soluble decacationic fullerene monoadducts, C60[>M(C3N6+C3)2] and C70[>M(C3N6+C3)2], were investigated. In the presence of a high number of electron-donating iodide anions as parts of quaternary ammonium salts in the arm region, we found that C70[>M(C3N6+C3)2] produced more highly reactive HO• radical than C60[>M(C3N6+C3)2], in addition to singlet oxygen (1O2). This finding offers an explanation of the preferential killing of Gram-positive and Gram-negative bacteria by C60[>M(C3N6+C3)2] and C70[>M(C3N6+C3)2], respectively. The hypothesis is that 1O2 can diffuse more easily into porous cell walls of Gram-positive bacteria to reach sensitive sites, while the less permeable Gram-negative bacterial cell wall needs the more reactive HO• to cause real damage.
PMCID: PMC3880553  PMID: 24396566
20.  OCT4 as a target of miR-34a stimulates p63 but inhibits p53 to promote human cell transformation 
Cell Death & Disease  2014;5(1):e1024-.
Human cell transformation is a key step for oncogenic development, which involves multiple pathways; however, the mechanism remains unclear. To test our hypothesis whether cell oncogenic transformation shares some mechanisms with the process of reprogramming non-stem cells to induced pluripotent stem cells (iPSC), we studied the relationship among the key factors for promoting or inhibiting iPSC in radiation-transformed human epithelial cell lines derived from different tissues (lung, breast and colon). We unexpectedly found that p63 and OCT4 were highly expressed (accompanied by low expressed p53 and miR-34a) in all transformed cell lines examined when compared with their non-transformed counterparts. We further elucidated the relationship of these factors: the 3p strand of miR-34a directly targeted OCT4 by binding to the 3′ untranslated region (3′-UTR) of OCT4 and, OCT4, in turn, stimulated p63 but inhibited p53 expression by binding to a specific region of the p63 or p53 promoter. Moreover, we revealed that the effects of OCT4 on promoting cell oncogenic transformation were by affecting p63 and p53. These results support that a positive loop exists in human cells: OCT4 upregulation as a consequence of inhibition of miR-34a, promotes p63 but suppresses p53 expression, which further stimulates OCT4 upregulation by downregulating miR-34a. This functional loop contributes significantly to cell transformation and, most likely, also to the iPSC process.
PMCID: PMC4040665  PMID: 24457968
Cell Transformation; OCT4; miR-34a; p53; p63
21.  miR-1207-5p and miR-1266 suppress gastric cancer growth and invasion by targeting telomerase reverse transcriptase 
Cell Death & Disease  2014;5(1):e1034-.
hTERT is the catalytic subunit of the telomerase complex. Elevated expression of hTERT is associated with the expansion and metastasis of gastric tumor. In this study, we aimed to identify novel tumor suppressor miRNAs that restrain hTERT expression. We began our screen for hTERT-targeting miRNAs with a miRNA microarray. miRNA candidates were further filtered by bioinformatic analysis, general expression pattern in different cell lines, gain-of-function effects on hTERT protein and the potential of these effects to suppress hTERT 3′ untranslated region (3′UTR) luciferase activity. The clinical relevance of two miRNAs (miR-1207-5p and miR-1266) was evaluated by real-time RT-PCR. The effects of these miRNAs on cell growth, cell cycle and invasion of gastric cancer cells were measured with CCK-8, flow cytometry and transwell assays. Finally, the ability of these miRNAs to suppress the transplanted tumors was also investigated. Fourteen miRNAs were identified using a combination of bioinformatics and miRNA microarray analysis. Of these fourteen miRNAs, nine were expressed at significantly lower levels in hTERT-positive cell lines compared with hTERT-negative cell lines and five could downregulate hTERT protein expression. Only miR-1207-5p and miR-1266 interacted with the 3′ UTR of hTERT and the expression levels of these two miRNAs were significantly decreased in gastric cancer tissues. These two miRNAs also inhibited gastric tumor growth in vitro and in vivo. Altogether, miR-1207-5p and miR-1266 were determined to be hTERT suppressors in gastric cancer, and the delivery of these two miRNAs represents a novel therapeutic strategy for gastric cancer treatment.
PMCID: PMC4040688  PMID: 24481448
tumor-suppressor miRNA; hTERT; gastric cancer
22.  A modified fractal zone plate with extended depth of focus in spectral domain optical coherence tomography 
Journal of optics (2010)  2011;13(5):10.1088/2040-8978/13/5/055301.
In optical coherence tomography (OCT) systems, there is a trade-off between the depth of focus (DOF) and lateral resolution when conventional lenses are used. We propose a new method that employs a modified fractal generalized zone plate (MFraGZP) combined with a conventional lens to improve the trade-off effect, with an extended DOF of about 2.5 mm (14 times larger) while the lateral resolution is maintained at ~9.5 μm. As an example, images of the calibration microspheres are obtained and demonstrated with the extended DOF in a spectral domain OCT system.
PMCID: PMC3864818  PMID: 24353894
optical coherence tomography; depth of focus; fractal zone plate
23.  An SNP linkage scan identifies significant Crohn's disease loci on chromosomes 13q13.3 and, in Jewish families, on 1p35.2 and 3q29 
Genes and immunity  2008;9(2):10.1038/sj.gene.6364460.
Inflammatory bowel disease (IBD) is a complex genetic disorder of two major phenotypes, Crohn's disease (CD) and ulcerative colitis (UC), with increased risk in Ashkenazi Jews. Twelve genome-wide linkage screens have identified multiple loci, but these screens have been of modest size and have used low-density microsatellite markers. We, therefore, performed a high-density single-nucleotide polymorphism (SNP) genome-wide linkage study of 993 IBD multiply affected pedigrees (25% Jewish ancestry) that contained 1709 IBD-affected relative pairs, including 919 CD–CD pairs and 312 UC–UC pairs. We identified a significant novel CD locus on chromosome 13p13.3 (peak logarithm of the odds (LOD) score = 3.98) in all pedigrees, significant linkage evidence on chromosomes 1p35.1 (peak LOD score = 3.5) and 3q29 (peak LOD score = 3.19) in Jewish CD pedigrees, and suggestive loci for Jewish IBD on chromosome 10q22 (peak LOD score = 2.57) and Jewish UC on chromosome 2q24 (peak LOD score = 2.69). Nominal or greater linkage evidence was present for most previously designated IBD loci (IBD1–9), notably, IBD1 for CD families at chromosome 16q12.1 (peak LOD score = 4.86) and IBD6 in non-Jewish UC families at chromosome 19p12 (peak LOD score = 2.67). This study demonstrates the ability of high information content adequately powered SNP genome-wide linkage studies to identify loci not observed in multiple microsatellite-based studies in smaller cohorts.
PMCID: PMC3858857  PMID: 18246054
Crohn's disease; ulcerative colitis; linkage; genetics
24.  Novel amidines and analogues as promising agents against intracellular parasites: a systematic review 
Parasitology  2013;140(8):10.1017/S0031182013000292.
Parasitic protozoa comprise diverse aetiological agents responsible for important diseases in humans and animals including sleeping sickness, Chagas disease, leishmaniasis, malaria, toxoplasmosis and others. They are major causes of mortality and morbidity in tropical and subtropical countries, and are also responsible for important economic losses. However, up to now, for most of these parasitic diseases, effective vaccines are lacking and the approved chemotherapeutic compounds present high toxicity, increasing resistance, limited efficacy and require long periods of treatment. Many of these parasitic illnesses predominantly affect low-income populations of developing countries for which new pharmaceutical alternatives are urgently needed. Thus, very low research funding is available. Amidine-containing compounds such as pentamidine are DNA minor groove binders with a broad spectrum of activities against human and veterinary pathogens. Due to their promising microbicidal activity but their rather poor bioavailability and high toxicity, many analogues and derivatives, including pro-drugs, have been synthesized and screened in vitro and in vivo in order to improve their selectivity and pharmacological properties. This review summarizes the knowledge on amidines and analogues with respect to their synthesis, pharmacological profile, mechanistic and biological effects upon a range of intracellular protozoan parasites. The bulk of these data may contribute to the future design and structure optimization of new aromatic dicationic compounds as novel antiparasitic drug candidates.
PMCID: PMC3815587  PMID: 23561006
intracellular parasites; chemotherapy; aromatic amidines; arylimidamides
25.  A set of microRNAs mediate direct conversion of human umbilical cord lining-derived mesenchymal stem cells into hepatocytes 
Cui, L | Shi, Y | Zhou, X | Wang, X | Wang, J | Lan, Y | Wang, M | Zheng, L | Li, H | Wu, Q | Zhang, J | Fan, D | Han, Y
Cell Death & Disease  2013;4(11):e918-.
In a previous study, we elucidated the specific microRNA (miRNA) profile of hepatic differentiation. In this study, we aimed to clarify the instructive role of six overexpressed miRNAs (miR-1246, miR-1290, miR-148a, miR-30a, miR-424 and miR-542-5p) during hepatic differentiation of human umbilical cord lining-derived mesenchymal stem cells (hMSCs) and to test whether overexpression of any of these miRNAs is sufficient to induce differentiation of the hMSCs into hepatocyte-like cells. Before hepatic differentiation, hMSCs were infected with a lentivirus containing a miRNA inhibitor sequence. We found that downregulation of any one of the six hepatic differentiation-specific miRNAs can inhibit HGF-induced hepatic differentiation including albumin expression and LDL uptake. Although overexpression of any one of the six miRNAs alone or liver-enriched miR-122 cannot initiate hepatic differentiation, ectopic overexpression of seven miRNAs (miR-1246, miR-1290, miR-148a, miR-30a, miR-424, miR-542-5p and miR-122) together can stimulate hMSC conversion into functionally mature induced hepatocytes (iHep). Additionally, after transplantation of the iHep cells into mice with CCL4-induced liver injury, we found that iHep not only can improve liver function but it also can restore injured livers. The findings from this study indicate that miRNAs have the capability of directly converting hMSCs to a hepatocyte phenotype in vitro.
PMCID: PMC3847311  PMID: 24232094
miRNA; mesenchymal stem cells; hepatic differentiation; hepatocytes

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