Biomedical subjects

Yao Wang

Publications and source records attributed to Yao Wang.

At least 19 recordsLinked to original sources

PubMed2026

CoxFormer enables spatial omics inference with multimodal generative modeling.

Gene co-expression maps transcriptome-wide gene-gene relationships, yet high-quality estimates cover less than half the genome. Meanwhile, spatial omics either profiles restricted in situ panels or lacks cellular resolution. Extending co-expression transcriptome-wide could overcome these limitations by inferring unassayed gene expression at subcellular resolution. Here we show that CoxFormer integrates literature-derived gene knowledge with co-expression networks from bulk tissues and large-scale single-cell atlases to learn 512-dimensional representations for 32,016 human genes. These embeddings capture functional gene relationships and serve as a generative prior for spatial inference across platforms and modalities. Without requiring a matched single-cell RNA-sequencing reference, CoxFormer supports four applications beyond measured genes: histology-based expression imputation, gene activity prediction from chromatin accessibility, subcellular super-resolution inference, and pathological region detection. Together, CoxFormer extends gene embedding from gene- and cell-level tasks to whole-transcriptome spatial inference, providing a unified framework for biological analysis beyond the limited gene coverage of current spatial omics technologies.

Humans↗

PubMed2026

Causal effects of cholelithiasis on hepatopancreatobiliary diseases: a multi-cohort Mendelian randomization study.

BACKGROUND: Cholelithiasis is commonly associated with multiple hepatopancreatobiliary diseases, yet whether these relationships reflect causal mechanisms or shared risk factors remains unclear. METHODS: We performed a phenome-oriented two-sample Mendelian randomization (MR) analysis to evaluate the causal impact of genetic liability to cholelithiasis across hepatopancreatobiliary outcomes. Independent genome-wide significant variants were selected as instrumental variables. Primary analyses used inverse variance weighting, complemented by sensitivity analyses, reverse MR, and multivariable MR adjusting for body mass index (BMI). RESULTS: Genetic predisposition to cholelithiasis was associated with increased risk of acute pancreatitis and extrahepatic cholangiocarcinoma (eCCA), with consistent directionality across datasets.The association with acute pancreatitis was interpreted as a positive control, whereas the null association with alcohol-induced acute pancreatitis served as a negative control. No causal association was observed for portal vein thrombosis. Sensitivity analyses, including MR-PRESSO and MR Steiger filtering, supported the robustness and directionality of the causal estimates. Reverse MR analyses showed no consistent evidence supporting reverse causality. Multivariable MR indicated that observed effects were not fully explained by BMI-related pathways. CONCLUSION: These findings suggest that cholelithiasis susceptibility may contribute to the broader hepatopancreatobiliary disease network, extending its clinical relevance beyond a localized biliary disorder.

Mendelian Randomization Analysis↗

PubMed2026

Dual Transcranial Direct Current Stimulation Modulates Hierarchical Functional Network Organization in Post-Stroke Cognitive Impairment: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the clinical efficacy of dual transcranial direct current stimulation (tDCS) in patients with post-stroke cognitive impairment (PSCI) and to explore the effects on the hierarchical organization of functional brain networks, ranging from regional synchronization to inter-regional connectivity and global network topology. METHODS: In this randomized, double-blind, sham-controlled trial, 74 PSCI patients received conventional therapy alongside either active dual-tDCS (n = 38) or sham stimulation (n = 36). Active tDCS targeted the dorsolateral prefrontal cortex (DLPFC) via anodal-left/cathodal-right nodes (2.0 mA, 20 min/day, 20 sessions). The primary outcome was the Montreal Cognitive Assessment (MoCA). Secondary outcomes included the Mini-Mental Status Examination (MMSE), Stroop Test (ST), Trail Making Test (TMT), Wechsler Memory Scale (WMS), and Barthel Index (BI). A subgroup of 36 participants (18 per group) underwent resting-state functional magnetic resonance imaging (rs-fMRI) to analyze regional homogeneity (ReHo), functional connectivity (FC), and network topology. Partial correlations assessed the association between neuroimaging alterations and clinical improvements. RESULTS: The tDCS group showed significantly greater improvements in MoCA scores (tDCS: 5.74 ± 2.76 vs. sham: 2.69 ± 2.69; t = 4.799, p < 0.001) as well as in attention and memory domains compared to the sham group. The rs-fMRI changes included increased ReHo in the right middle temporal gyrus (MTG) and the left inferior frontal gyrus (IFG), and reduced FC between the right MTG-left superior frontal gyrus and left IFG-cerebellum (p < 0.05, FWE-corrected). Additionally, small-worldness and global efficiency increased (p < 0.05) with these alterations correlating with clinical recovery. Adverse events were rare and self-limiting. CONCLUSION: Dual-tDCS over bilateral DLPFC safely improves cognitive recovery in PSCI. These clinical gains are associated with rs-fMRI alterations, specifically in regional synchronization, inter-regional connectivity, and global topology, which suggest a potential biomarker for monitoring tDCS efficacy, offering a rationale for precision neuromodulation in stroke rehabilitation.

Humans↗

PubMed2025

Therapeutic Targeting of Decr1 Ameliorates Cardiomyopathy by Suppressing Mitochondrial Fatty Acid Oxidation in Diabetic Mice.

BACKGROUND: A significant increase in mitochondrial fatty acid oxidation (FAO) is now increasingly recognized as one of the metabolic alterations in diabetic cardiomyopathy (DCM). However, the molecular mechanisms underlying mitochondrial FAO impairment in DCM remain to be fully elucidated. METHODS: A type 2 diabetes (T2D) mouse model was established by a combination of high-fat diet (HFD) and streptozotocin (STZ) injection. Neonatal rat cardiomyocytes were treated with high glucose (HG) and palmitic acid (HP) to simulate diabetic cardiac injury. Gain- and loss-of-function approaches and RNA sequencing were utilized to investigate the role and mechanism of 2,4-dienoyl-CoA reductase 1 (Decr1) in DCM. RESULTS: By integrating the genomic data available in the Gene Expression Omnibus (GEO) with DCM rodents, we found that the transcriptional level of Decr1 was consistently upregulated in DCM (+255% for diabetic heart, p < 0.0001; +281% for diabetic cells, p < 0.0001). Cardiomyocytes-specific knockdown of Decr1 preserved cardiac function (+41% for EF, p < 0.0001; +24% for FS, p = 0.0052), inhibited cardiac hypertrophy (-34%, p < 0.0001), fibrosis (-69%, p < 0.0001), apoptosis (-56%, p < 0.0001) and oxidative damage (-59%, p < 0.0001) in DCM mice, while cardiomyocytes-specific overexpression of Decr1 aggravated DCM (-28% for EF, p = 0.0347; -17% for FS, p = 0.0014). Deletion of Decr1 prevented high glucose/palmitate (HG/HP)-induced hypertrophy (-22%, p = 0.0006), mitochondrial dysfunction and apoptosis (-74%, p < 0.0001) in cultured cardiomyocytes. Furthermore, RNA sequencing and functional analysis showed that Decr1 interacted with and upregulated pyruvate dehydrogenase kinase 4 (PDK4) in injured cardiomyocytes, and overexpression of PDK4 eliminated the benefits of Decr1 downregulation in DCM (-20% for EF, p = 0.0071; -28% for FS, p = 0.0022). Mechanistically, PDK4 acted as a kinase that induced phosphorylation and mitochondrial translocation of HDAC3. In the mitochondria, HDAC3 mediated the deacetylation of dehydrogenase trifunctional multienzyme complex α subunit (HADHA), contributing to excessive mitochondrial FAO and subsequent cardiac injury. From a screening of 256 natural products, we identified Atranorin and Kurarinone as potential inhibitors of Decr1, both demonstrating protective effects against DCM (Atranorin, +21% for EF, p = 0.0134; +24% for FS, p = 0.0006; Kurarinone, +20% for EF, p = 0.0183; +27% for FS, p = 0.0001). CONCLUSIONS: Our study delineates a molecular mechanism by which Decr1 potentiated higher mitochondrial lipid oxidation and cardiac damage by enhancing HADHA deacetylation through the PDK4/HDAC3 signalling pathway.

Animals↗

PubMed2006

First-principles study of interaction of cluster Au32 with CO, H2, and O2.

First-principles calculations are performed to study the interaction of cluster Au(32) with small molecules, such as CO, H(2), and O(2). The cagelike Au(32)(I(h)) shows a higher chemical inertness than the amorphous Au(32)(C(1)) with respect to the interaction with small molecules CO, H(2), and O(2). H(2) can only be physically adsorbed on Au(32)(I(h)), while it can be dissociatively chemisorbed on Au(32)(C(1)). Although CO can be chemically adsorbed on Au(32)(I(h)) and Au(32)(C(1)) with one electron transferred from Au(32) to the antibonding pi* orbit of CO, it is bound more strongly on Au(32)(C(1)) than on Au(32)(I(h)). Spin polarized and spin nonpolarized calculations result almost identical ground state structures of Au(32)(I(h))-O(2) and Au(32)(C(1))-O(2), in which O(2) is dissociatively chemisorbed.

Journal Article↗

PubMed2006

Bcl-2 enhances neurogenesis and inhibits apoptosis of newborn neurons in adult rat brain following a transient middle cerebral artery occlusion.

To determine whether Bcl-2 could influence adult neurogenesis and prevent apoptosis of newborn neurons, we injected Bcl-2 expressing plasmid into the lateral ventricle of rat brain immediately following a 30-min occlusion of the middle cerebral artery (MCAO). We found that Bcl-2 increased neural progenitor cells (BrdU+-DCX+) in the ipsilateral striatum, newborn immature neurons (BrdU+-Tuj-1+) and newborn mature neurons (BrdU+-MAP-2+) in the ipsilateral striatum and frontal cortex at 1 to 4 weeks following MCAO. Bcl-2 overexpression promoted development of newborn neurons into GABAergic and cholinergic neurons in the ipsilateral striatum. Moreover, Bcl-2 significantly decreased the apoptosis of newborn neurons, determined by double staining of Tuj-1 and activated caspase-3 (Tuj-1+-Casp+). These results indicate that overexpression of Bcl-2 in adult rat brain enhances neurogenesis and survival of newborn neurons. Increasing neurogenesis and preventing the death of newborn neuron may be a strategy to aid in the repair of adult brain after stroke.

Animals↗

PubMed2006

Regulation of antiviral responses by a direct and specific interaction between TRAF3 and Cardif.

Upon recognition of viral infection, RIG-I and Helicard recruit a newly identified adapter termed Cardif, which induces type I interferon (IFN)-mediated antiviral responses through an unknown mechanism. Here, we demonstrate that TRAF3, like Cardif, is required for type I interferon production in response to intracellular double-stranded RNA. Cardif-mediated IFNalpha induction occurs through a direct interaction between the TRAF domain of TRAF3 and a TRAF-interaction motif (TIM) within Cardif. Interestingly, while the entire N-terminus of TRAF3 was functionally interchangeable with that of TRAF5, the TRAF domain of TRAF3 was not. Our data suggest that this distinction is due to an inability of the TRAF domain of TRAF5 to bind the TIM of Cardif. Finally, we show that preventing association of TRAF3 with this TIM by mutating two critical amino acids in the TRAF domain also abolishes TRAF3-dependent IFN production following viral infection. Thus, our findings suggest that the direct and specific interaction between the TRAF domain of TRAF3 and the TIM of Cardif is required for optimal Cardif-mediated antiviral responses.

Adaptor Proteins, Signal Transducing↗

PubMed2006

Inhibins differentially antagonize activin and bone morphogenetic protein action in a mouse adrenocortical cell line.

Inhibin, a member of the TGF-beta superfamily, has been proposed to act as an inhibitor of activin and bone morphogenetic protein (BMP) by sequestering their type II receptors in nonsignaling complexes with betaglycan. This mechanism of inhibin action was tested in a mouse adrenocortical (AC) cell line by examining the effects of inhibins A and B on cytochrome P450 17alpha-hydroxylase 17,20-lyase (Cyp17) expression and 17alpha-hydroxylase activity, measured by progesterone 17alpha-hydroxylation, in the absence and presence of activin or BMP isoforms. Cyp17 mRNA endogenously expressed by AC cells was suppressed by activins A and B and BMP-2, -6, and -7, and each ligand accordingly inhibited 17alpha-hydroxyprogesterone production (IC(50) of 0.24, 0.27, 0.4, 0.51, and 2.2 nm, respectively). Neither inhibin A nor inhibin B alone affected Cyp17 expression or 17alpha-hydroxyprogesterone production. Both inhibin A and inhibin B blocked the inhibitory actions of activins A and B in AC cells, supporting the antiactivin model of inhibin action. Inhibin A provided more potent and effective antagonism of both activins than did inhibin B, and activin A was less subject to antagonism by either inhibin than was activin B. In contrast to the major antagonism of activin by both inhibins, only inhibin A antagonized the actions of BMP-2, BMP-6, and BMP-7, whereas inhibin B was ineffective against all tested BMP isoforms except BMP-7 at high concentrations. These results provide limited support for the anti-BMP model of inhibin action and reveal that, relative to inhibin A, inhibin B essentially behaves as a selective activin antagonist in AC cells. In conclusion, inhibins A and B differentially antagonize the actions of activins and BMPs to control adrenocortical C(19) steroid production.

Activins↗

PubMed2006

Improvement of Fe/MgO catalysts by calcination for the growth of single- and double-walled carbon nanotubes.

Calcination at 900-1000 degrees C for 8-12 h of an Fe/MgO catalyst prepared by impregnation was found to result in a uniform MgFe2O4/MgO solid solution that showed a successful settling of well-dispersed iron species into the MgO lattice. During methane reduction, many iron-containing particles with a diameter of about 4 nm were formed on the catalyst surface to provide numerous active sites for the growth of single- and double-walled carbon nanotubes. There was a significant improvement of the Fe/MgO catalyst that resulted in a high yield of impurity-free nanotubes. Using C2H4 cracking at 600 degrees C and transmission electron microscope observations, the Fe species distribution in the catalysts and microscope images of nanotube growth were described in detail. H2 reduction of the calcined Fe/MgO catalyst was found to cause the formation of iron layers on the catalyst surface, which resulted in the growth of only carbon layers. The results are useful for understanding changes in the metal species distribution in the catalysts and the nanotube growth mechanism, and they provide a simple method to improve Fe/MgO catalysts.

Journal Article↗

PubMed2006

Nitric oxide enhances collagen synthesis in cultured human tendon cells.

Collagen deposition is an important process that occurs during wound healing. We and others have shown that nitric oxide (NO) is important in tendon healing. The mechanisms whereby healing is enhanced are, however, undetermined. The aim of this study was to investigate whether NO could enhance collagen synthesis in cultured human tendon cells via exogenous NO and via an adenovirus containing the gene for inducible nitric oxide synthase (Ad-iNOS). Tendon cells from the torn edge of the tendons of patients undergoing rotator cuff repair surgery were cultured following collagenase digestion, and stimulated with exogenous NO (SNAP), transfected with Ad-iNOS, and treated with the NOS inhibitor, L-NMMA. Total protein and collagen synthesis were evaluated by (3)H-proline and collagenase sensitive (3)H-proline incorporation in human tendon cells. High doses of exogenous NO (SNAP) inhibited collagen synthesis. Lower doses enhanced total protein and collagen synthesis of the tendon cells. Ad-iNOS successfully transfected active iNOS into human tendon cells in vitro and also enhanced total protein and collagen synthesis of the tendon cells. The NOS inhibitor, L-NMMA, inhibited the effects of iNOS on the cells. Our studies show for first time that nitric oxide can enhance collagen synthesis in human tendon cells in vitro. These results may explain, in part, at least, the beneficial effects of NO donors in animal models and during the treatment of tendonopathies in human clinical trials. .

Adenoviridae↗

PubMed2006

Gene expression changes in SNAP-stimulated and iNOS-transfected tenocytes--expression of extracellular matrix genes and its implications for tendon-healing.

Nitric oxide (NO) has a variety of physiological roles, including acting as a key mediator in various phases of tendon healing, but its importance as a modulator of gene expression during tendon healing has not been well studied. The current study used microarray analysis to elucidate global gene expression after transfection with inducible nitric oxide synthase (iNOS) in tenocytes isolated from the injured rotator cuff tendons of human patients. We show that the expression of a wide range of genes is affected by NO, with many activated genes having known roles in healing. Of particular significance is that NOS overexpression stimulates the transcription and translation of a range of extracellular matrix genes important to the structure of connective tissues such as tendons, including collagen Ialpha1, collagen IIIalpha1, collagen IValpha5, biglycan, decorin, laminin, and matrix metalloproteinase 10 (MMP10). These genes were also shown to respond to stimulation by the NO donor S-nitroso-N-acetyl-penicillamine (SNAP) in a dose-dependent manner. We further show that varying levels of NO significantly affect cellular adhesion in tenocytes, a critical process during tendon repair. These findings will be of use when optimizing the dose of NO delivery in further work investigating NO as potential treatment of tendon injuries.

Aged↗

PubMed2006

Rodent adrenocortical cells display high affinity binding sites and proteins for inhibin A, and express components required for autocrine signalling by activins and bone morphogenetic proteins.

Inhibins are expressed in the adrenal cortex, but little is known of their binding or role in the adrenal. The aims of the present study were, first, to establish whether a mouse adrenocortical (AC) cell line expresses inhibins/activins and bone morphogenetic proteins (BMP), along with proteins required for inhibin to antagonise activin and BMP actions and, secondly, to characterise and compare inhibin binding sites and proteins in the rat adrenal gland and AC cells. AC cells were found to: (1) express mRNA for multiple BMPs (BMP-2, -3, -4, -6, -8a), growth/differentiation factors (GDF-1, -3, -5, -9), Lefty A and B, and the inhibin alpha, beta(A) and beta(B) subunits (2) secrete inhibin A and inhibin B and (3) express mRNA encoding the inhibin co-receptor, betaglycan, along with activin and BMP type I (ALK2-7) and type II (ActRII, ActRIIB, BMPRII) receptors, and binding proteins (follistatin, BAMBI, gremlin). When applied to sections of rat adrenal glands, [(125)I]inhibin A specifically bound to cells of the adrenal cortex, mainly in the zona reticularis. Scatchard analyses of in vitro [(125)I]inhibin A binding to dispersed rat adrenal cells and AC cells revealed sites of high affinity (K(d)(1) of 0.18 and 0.15 nM, respectively) and low affinity (K(d)(2) of 2.6 and 1.3 nM, respectively. Competition for [(125)I]inhibin A binding by activin A or B (30 nM) was negligible, whereas BMP-2, -6 and -7 competed for between 21 and 33% of specific inhibin A binding (IC(50) between 0.2 and 0.3 nM). Inhibin B crossreaction with inhibin A binding sites was < 8%. Multiple binding protein complexes (molecular weight ranging from 35 to > 220 kDa) were affinity labelled by [(125)I]inhibin A on both the primary rat adrenal and AC cells. The species of > 220 kDa were shown by immunoprecipitation to include betaglycan, the species of 105 kDa is consistent in size with type II receptors for activin/BMP, and that of 62 kDa co-migrates with the inhibin-follistatin complex. In summary, the results show that inhibin A binds selectively and with both high and low affinity to AC cells via multiple binding proteins, including a single betaglycan-like species. The results support the role of glycosylated betaglycan in the high affinity binding of inhibin A, but provide consistent evidence from two independent sources of adrenal cells that inhibin A interacts with several membrane proteins in addition to those currently understood to mediate the anti-activin/BMP actions of inhibin.

Activins↗

PubMed2006

[Repair of skin soft tissue defects with new overlapping tissue expansion techniques].

OBJECTIVE: To improve the efficiency of skin soft tissue expansion with the overlapping tissue expansion techniques. METHODS: From June 2003 to March 2005, 5 cases of skin soft tissue defects were treated with the overlapping tissue expansion technique-two overlapped expanders in one soft tissue pocket, which was different from the traditional technique--one expander in one soft tissue pocket. Five patients included 3 males and 2 females, aging from 11 to 28 years. The defect was caused by scar of forearm in 2 cases, by melanotic nevus in 1 case and by cicatricial baldness in 2 cases. The disease course was 1.5 to 24 years. The defect size ranged from 12 cm X 5 cm to 13 cm X 12 cm. RESULTS: Skin expansion process was satisfactory and skin defect was completely repaired with the expanded skin tissue in one operation in 5 cases. After operation, the wound of donor-recipient site healed by first intention. All patients were followed up from 3 to 15 months, no contracture, pigmentation and scar occurred at the expanded skin area. The long-term appearances were satisfactory. CONCLUSION: Compare with the traditional tissue expansion techniques, the new overlapping tissue expansion techniques can apparently improve the efficiency of skin soft tissue expansion. It is suitable for the patients whose expandable skin is limited or no more skin tissue can be dissected near the skin defect and who need more expandable skin to repair skin defect.

Adolescent↗

PubMed2006

[Preparation and structural characterization of ZnTHPP/TiO2 hybrid material].

Using sol-gel method to make tetra-meso (hydroxylphenyl) zinc porphyrin (ZnTHPP) trapped in inorganic networks of TiO2, a new organic/inorganic hybrid material was prepared. The structures and morphology of this material were characterized by thermogravimetric analyses (TGA), infrared spectrum (FTIR), UV-Vis spectrum (UV), diffuse reflectance spectroscopy (DRS), and scanning electron microscopy (SEM), indicating that ZnTHPP/TiO2 hybrid material possessed excellent thermostability, and ZnTHPP was trapped in TiO2 network with chemical bonds. In addition, ZnTHPP embedding can enlarge the absorption range of light for TiO2 effectivelly.

English Abstract↗

PubMed2005

Controlled growth and photocatalytic properties of CdS nanocrystals implanted in layered metal hydroxide matrixes.

Layered double hydroxide Cd(1)(-)(x)()Al(x)()(OH)(2)(DS)(x)().3.0H(2)O (CdAlDS) and a related hydroxide salt compound Cd(2)(OH)(3)(DS).2.5H(2)O (CdDS), where DS stands for dodecyl sulfate sandwiched between two adjacent inorganic layers, have been synthesized and used as precursors for CdS nanoparticle growth. Through a gas/solid reaction, CdS nanocrystals implanted in the layer matrixes of the layered double hydroxides are grown, and the sizes of the nanocrystals vary in the range of 3-6 nm in diameter. The presence of trivalent Al cations in the layered double hydroxide can be taken advantage of to control the size of the CdS nanocrystals, and it also helps to prevent the formed nanocrystals from extraction from the solid matrixes. The nano-CdS implanted composite exhibits high photocatalytic activity for degradation of the nonbiodegradable rhodamine B under both UV and visible irradiations.

Journal Article↗

PubMed2005

Functional basis for the overlap in ligand interactions and substrate specificities of matrix metalloproteinases-9 and -2.

The MMPs (matrix metalloproteinases) MMP-9 and -2 each possess a unique CBD (collagen-binding domain) containing three fibronectin type II-like modules. The present experiments investigated whether the contributions to ligand interactions and enzymatic activities by the CBD of MMP-9 (CBD-9) corresponded to those of CBD in MMP-2 (CBD-2). The interactions of recombinant CBD-9 with a series of collagen types and extracellular matrix molecules were characterized by protein-protein binding assays. CBD-9 bound native and denatured type I, II, III, IV and V collagen, as well as Matrigel and laminin, with apparent K(d) values of (0.1-6.8)x10(-7) M, which were similar to the K(d) values for CBD-2 [(0.2-3.7)x10(-7) M]. However, CBD-9 bound neither native nor denatured type VI collagen. We also generated two modified MMPs, MMP-9(E402A) and MMP-2(E404A), by site-specific mutations in the active sites to obtain enzymes with intact ligand binding, but abrogated catalytic properties. In subsequent competitive binding assays, CBD-9 and MMP-9(E402A) inhibited the interactions of MMP-2(E404A) and, conversely, CBD-2 and MMP-2(E404A) competed with MMP-9(E402A) binding to native and denatured type I collagens, pointing to shared binding sites. Importantly, the capacity of CBD-9 to disrupt the MMP-9 and MMP-2 binding of collagen translated to inhibition of the gelatinolytic activity of the enzymes. Collectively, these results emphasize the essential contribution of CBD-9 to MMP-9 substrate binding and gelatinolysis, and demonstrate that the CBDs of MMP-9 and MMP-2 bind the same or closely positioned sites on type I collagen.

Animals↗

PubMed2005

Inhibition of human lens epithelial B-3 cell proliferation by adenovirus-mediated transfer of antisense c-myc construct.

PURPOSE: To investigate the effects of adenovirus-mediated transfer of antisense c-myc construct on human lens epithelial B-3 (HLE B-3) cell proliferation, apoptosis and cell cycle. METHODS: HLE B-3 cell cultures were transduced with replication-defective adenovirus bearing either a nuclear-targeted beta-galactosidase (Ad-lacZ) or an antisense c-myc construct (Ad-AS-myc). The presence of beta-galactosidase activity in the transduced cultures was detected by immunohistochemical X-Gal staining, while c-myc mRNA and protein expression levels were evaluated by RT-PCR and Western blot analysis. HLE B-3 cell proliferation within 96 h after the transduction was analyzed by cell counting and MTT colorimetric assay. Apoptosis and cell cycle of the HLE-B3 cells were examined by flow-cytometric analysis. RESULTS: The mean transduction efficiency was 80% for HLE B-3 cells. Downregulation of c-myc mRNA and protein expression was noticed at 48, 96 and 144 h after the transduction with Ad-AS-myc. Cytostatic effects of Ad-AS-myc in HLE B-3 cells were obvious within 96 h after the transduction. An increased incidence of apoptosis and G1-phase arrest was identified in the Ad-AS-myc-transduced HLE B-3 cells. CONCLUSIONS: HLE B-3 cells were successfully transduced with adenovirus-mediated antisense c-myc construct. Ad-AS-myc transduction could significantly inhibit cell proliferation and induce cell apoptosis and G1-phase arrest in HLE B-3 cells. It may provide a novel approach for prevention of posterior capsular opacification.

Adenoviruses, Human↗

PubMed2005

Matrix metalloproteinase-2 contributes to cancer cell migration on collagen.

Matrix metalloproteinases (MMP) are central to tissue penetration by cancer cells, as tumors expand and form metastases, but the mechanism by which MMP-2 contributes to cancer cell migration is not well understood. In the present experiments, both a broad-spectrum MMP inhibitor and the isolated collagen binding domain (CBD) from MMP-2 inhibited cell migration on native type I collagen. These results verified the involvement of MMPs in general and showed that MMP-2, specifically, contributes to cell migration by a mechanism involving MMP-2 interaction with collagen. To exclude potential overlapping effects of MMP-9, additional experiments showed that MMP-2 also contributed to migration of MMP-9-/- cells. To investigate whether the homologous CBD from human fibronectin also inhibited cell migration, we first showed that fragmentation of fibronectin is a feature of breast cancer tumors and that several fragments contained the CBD. However, the recombinant fibronectin domain did not alter cell migration on collagen. This lack of effect on cell migration was explored in competitive protein-protein binding assays, which showed that the affinity of MMP-2 for collagen exceeds that of fibronectin. Furthermore, whereas the isolated MMP-2 CBD inhibited the gelatinolytic activities of MMP-2 and tumor extracts, such an inhibition was not characteristic of the corresponding fibronectin domain. Together, our results provide evidence that MMP-2 is an important determinant of cancer cell behavior but is not inhibited by the collagen binding segment of fibronectin.

Binding Sites↗