MicroRNA-98 regulates osteogenic differentiation of human bone mesenchymal stromal cells by targeting BMP2.

To study the effects of microRNA-98 (miR-98) on human bone mesenchymal stromal cells (hBMSCs). The patients undergoing hip arthroplasty were selected by inclusion/exclusion criteria for this study. The extracted hBMSCs were detected of osteogenic differentiation by alizarin red S staining, and of cell phenotype by flow cytometry. Bioinformatics, dual luciferase report, western blotting, RT-PCR and immunoblotting were used in our study. The hBMSCs were divided into miR-98 mimics, miR-98 negative control (NC), miR-98 inhibitors, Mock and miR-98 inhibitors + siBMP2 groups. Human bone mesenchymal stromal cells were extracted and purified in vitro and had specific cytological morphology, surface markers and abilities of self-renewal and differentiation. Compared with the NC group and Mock group, the miR-98 mimics group showed increased miR-98 level while the miR-98 inhibitors group decreased miR-98 level (both P < 0.01). Dual luciferase reporter showed BMP2 was the target gene of miR-98. The levels of mRNA and protein expression of BMP2, protein expression of RUNX2, alkaline phosphatase activity and osteocalcin content significantly decreased in the miR-98 mimics group while increased in the miR-98 inhibitors group and showed no changes in the NC group and Mock group (all P < 0.05). The miR-98 mimics group showed obviously declined stained red particles and the miR-98 inhibitors group showed opposite result. After lowering the expression of miR-98, osteogenic differentiation ability of hBMSCs rose, which was weakened by the transfection with siBMP2. miR-98 may regulate osteogenic differentiation of hBMSCs by targeting BMP2.

[Epithelial-mesenchymal transition in prostate cancer].

Prostate cancer (PCa) is a common disease in elderly men, its incidence ranking the second among all malignancies in males in Western countries and increasing in China in the last decade. Tumor metastasis is the main cause of death of PCa patients. In the development and progression of tumor, the tumorous cells in the infiltration area interact with their microenvironment, undergo epithelial-mesenchymal transition (EMT) and consequently cause distant metastases. So to study the role of EMT in the development and progression of tumor is of great significance for the treatment of PCa. This article reviews the relevant literature of the last 3 years and gives an overview of the factors affecting EMT in prostate cancer, aiming at a therapeutic target.

EGFRvIII Promotes the Proneural-Mesenchymal Transition of Glioblastoma Multiforme and Reduces Its Sensitivity to Temozolomide by Regulating the NF-κB/ALDH1A3 Axis.

(1) Background: Glioblastoma multiforme (GBM) is the most common and malignant intracranial tumor in adults. At present, temozolomide (TMZ) is recognized as the preferred chemotherapeutic drug for GBM, but some patients have low sensitivity to TMZ or chemotherapy resistance to TMZ. Our previous study found that GBM patients with EGFRvIII (+) have low sensitivity to TMZ. However, the reasons and possible mechanisms of the chemoradiotherapy resistance in GBM patients with EGFRvIII (+) are not clear. (2) Methods: In this study, tissue samples of patients with GBM, GBM cell lines, glioma stem cell lines, and NSG mice were used to explore the causes and possible mechanisms of low sensitivity to TMZ in patients with EGFRvIII (+)-GBM. (3) Results: The study found that EGFRvIII promoted the proneural-mesenchymal transition of GBM and reduced its sensitivity to TMZ, and EGFRvIII regulated of the expression of ALDH1A3. (4) Conclusions: EGFRvIII activated the NF-κB pathway and further regulated the expression of ALDH1A3 to promote the proneural-mesenchymal transition of GBM and reduce its sensitivity to TMZ, which will provide an experimental basis for the selection of clinical drugs for GBM patients with EGFRvIII (+).

[Inhibitory effect of siRNA targeting ADAM17 on the proliferation of prostate cancer PC-3 cells].

OBJECTIVE: To study the effect of siRNA targeting ADAM17 (ADAM17-siRNA) on the proliferation of prostate cancer PC-3 cells. METHODS: After transfecting PC-3 cells with ADAM17-siRNA 1 and ADAM17-siRNA 2, we detected the expressions of ADAM17 mRNA and protein by RT- PCR and Western blotting, respectively. We measured the changes in the proliferation and DNA synthesis of PC-3 cells by MTT and bromodeoxyuridine (BrdU) incorporation assay, examined the cell cycle profile by flow cytometry, and determined the expressions of the genes associated with PC-3 cell proliferation by Western blotting. RESULTS: Both ADAM17-siRNA 1 and 2 effectively reduced the expressions of ADAM17 mRNA and protein in the PC-3 cells. Knockdown of ADAM17 with the two siRNAs significantly inhibited cell proliferation as compared with the control group (0.43 +/- 0.57 and 0.44 +/- 0.64 vs 0.80 +/- 0.51, P < 0.05) and down-regulated DNA synthesis (0.48 +/- 0.43 and 0.54 +/- 0.59 vs 0.79 +/- 0.72, P < 0.05). The cell cycle profile showed that the cell population of the G1 phase was markedly higher in both the ADAM17-siRNA groups than in the control ([61.83 +/- 2.41]% and [59.78 +/- 1.92]% vs [41.38 +/- 1.53]%, P < 0.05), but that of the S phase remarkably lower in the former two than in the latter ([23.64 +/- 2.56]% and [25.24 +/- 1.86]% vs [33.51 +/- 1.47]%, P < 0.05), with a concomitant decrease in the expression of the cell cycle protein cyclin D1 and increase in the cyclin-dependent kinase inhibitor p21. CONCLUSION: ADAM17-siRNA can effectively inhibit the proliferation of PC-3 cells by up-regulating cyclin D1 and down-regulating p21 protein, and ADAM17 has a potential value in the gene therapy of prostate cancer.

[Treatment of non-traumatic avascular talar necrosis by transposition of vascularized cuneiform bone flap plus iliac cancellous bone grafting].

OBJECTIVE: To evaluate the outcome of cancellous bone grafting plus iliac cancellous bone in the treatment of non-traumatic avascular talar necrosis. METHODS: Twenty patients, 14 males and six females, eight at stage II, ten at stage III and three at stage IV according to the modified Ficat & Arlet necrosis classification system, were treated with vascularized bone flap from January 2000 to June 2005. RESULTS: All patients were followed up for a mean of 37 months (range: 14 to 68 months). The clinical function outcome evaluated by Kenwright criteria were excellent in 8 cases, good in 10 cases, fair in 1 case and poor in 1 case. Clinical symptom was completely or partially relieved. The necrotic area was filled with newly formed bone and the excellent-to-good rate was 90%. CONCLUSION: Transposition of vascularized cuneiform bone flap plus iliac cancellous bone grafting may be an ideal therapeutic method for non-traumatic avascular talar necrosis. And the clinical outcome is satisfactory.

[Study on ultraviolet upconversion emissions of Gd3+ induced by Tm3+ under 980 nm excitation].

Series of Tm3+/Yb3+ co-doped GdF3 powders were synthesized through an easy and mild hydrothermal method. The phase and purity of powders were characterized by powder X-ray diffraction (XRD) (Rigaku RU-200b). The morphologies of the samples were characterized by field emission scanning electron microscopy (FE SEM) (Hitachi S-4800). The ultraviolet (UV) up-conversion (UC)emission spectra were recorded by a fluorescence spectrophotometer (Hitachi F-4500) with a 980 nm semiconductor continuous wave laser diode as the excitation source. And the luminescent dynamics was measured by excitation with 980 nm using an optical parameter oscillator (OPO) laser pumped by a pulsed Nd : YAG laser with a pulse duration of 10 ns, repetition frequency of 10 Hz, and the signal was recorded by using a monochromator and an oscillograph. Under 980 nm excitation, Gd3+, acting as a kind of host ion in the studied system, and its UV UC emissions were observed and studied. The luminescent dynamics of the characteristic emission of Gd3+ (311.6 nm, 6P7/2 --> 8S7/2) was explored and studied. The luminescent dynamics analysis results indicated that, on UV UC emissions of Gd3+, Yb3+ ions served as primary sensitizer ions successively transferring energy to Tm3+ to populate the 3P2 level. Then, Tm3+ ions served as secondary sensitizer ions transferring energy to populate the multiple 6 I(J) states of Gd3+ 3P2 --> 3H6 (Tm3+): 8S7/2 --> 6 I(J) (Gd3+). Further, 6D(J) levels were populated through other energy transfer processes between Gd3+ and Yb3+ or Tm3+. Finally, UV UC emissions from the excited 6D9/2, 6 I(J), 6P5/2, and 6P7/2 states to the ground state 8S7/2 were observed. Meanwhile, Tm3+ acted as activator in its own UC emissions, and the article did not put emphasis on those except the 3P2 and 1 I6 levels to the ground state 3 H6 transitions. Especially, the dependences of UV UC emissions of Gd3+ on the Yb3+ concentrations, the Tm3+ concentrations, the annealing temperatures, and the excitation power densities of the 980 nm semiconductor continuous wave laser diode were studied, too.

miR-124-3p availability is antagonized by LncRNA-MALAT1 for Slug-induced tumor metastasis in hepatocellular carcinoma.

BACKGROUND: As an oncogene, long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) can promote tumor metastasis. Hyperexpression of MALAT1 has been observed in many malignant tumors, including hepatocellular carcinoma (HCC). However, the role and mechanism of MALAT1 in HCC remain unclear. METHODS: Thirty human HCC and paracancerous tissue specimens were collected, and the human hepatoma cell lines Huh7 and HepG2 were cultured according to standard methods. MALAT1 and Snail family zinc finger (Slug) expression were measured by real-time PCR, immunohistochemistry, and western blotting. Luciferase reporter assay and RNA immunoprecipitation (RIP) assay verified the direct interaction between miR-124-3p and Slug(SNAI2) or MALAT1. Wound healing and transwell assays were performed to examine invasion and migration, and a subcutaneous tumor model was established to measure tumor progression in vivo. RESULTS: MALAT1 expression was upregulated in HCC tissues and positively correlated with Slug expression. MALAT1 and miR-124-3p bind directly and reversibly to each other. MALAT1 silencing inhibited cell migration and invasion. miR-124-3p inhibited HCC metastasis by targeting Slug. CONCLUSIONS: MALAT1 regulates Slug through miR-124-3p, affecting HCC cell metastasis. Thus, the MALAT1/miR-124-3p/Slug axis plays an important role in HCC.

[Detection of ABO genotype genetic polymorphism by multiplex-PCR based sequencing and application in forensic medicine].

Multiplex PCR-direct sequencing method was established to detect 9 different SNPs in exon 6 and exon 7 of ABO genes and could identify at least 28 different ABO genotypes. Population study was carried out in a sample of 80 unrelated Chinese Tibetan minority individual dwelled in Qinghai Province. The method was also applied to forensic cases. A variety of degeneration forensic samples, including blood stain, hair root, swab, bone and mixed stain were successfully identified by this efficient method and in conformance with serological typing. There were no significant deviations from Hardy-Weinberg equilibrium in ABO genotypes of Tibetan population. The heterozygosity, polymorphic information content, discrimination power, paternity of exclusion, and probability of genetic identity were 0.675, 0.672, 0.874, 0.391, and 0.126 respectively. The gene frequency of ABO was O>B>A. The multiplex PCR-directed sequencing method can accurately and reliably detect ABO genotypes in many kinds of samples, and it improves personal identification efficiency. The ABO genotype is high variance in Qinghai Tibetan minority group, and it can be applied in forensic medicine and population genetic study.

Bioinspired Flexible and Highly Responsive Dual-Mode Strain/Magnetism Composite Sensor.

The mimicry of human skin to detect both oncoming and physical-contacting object is of great importance in the fields of manufacturing, artificial robots and vehicles, etc. Herein, a novel bioinspired flexible and highly responsive dual-mode strain/magnetism composite sensor, which works via both contact and contactless modes, is first fabricated by incorporating Fe3O4/silicone system into a carbon fiber aerogel (CFA). The distance dependence of magnetic field endorses the CFA/Fe3O4/silicone composite possible for spatial sensing due to the introduction of Fe3O4 magnetic nanoparticles. As a result, the as-prepared flexible sensor exhibits precise and real-time response not only to direct-contact compression as usual but also to contactless magnetic field in a wide frequency range from 0.1 to 10 Hz, achieving the maximum variance of 68% and 86% in relative electrical resistance, respectively. The contact and contactless sensing modes of the strain/magnetism sensor are clearly demonstrated by recording the speeds of bicycle riding and walking, respectively. Interestingly, this dual-mode composite sensor exhibits the capacity of identifying the contact and contactless state, which is the first report for flexible sensors. The current protocol is eco-friendly, facile, and thought-provoking for the fabrication of multifunctional sensors.

Genetic analysis of 15 STR loci in Chinese Han population from West China.

Allele frequencies for 15 short tandem repeat (STR) loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA) were obtained from 7,636 unrelated individuals of Chinese Han population living in Qinghai and Chongqing, China. Totally 206 alleles were observed, with the corresponding allele frequencies ranging from 0.0001-0.4982. Chi-square test showed that all of the STR loci agreed with the Hardy-Weinberg equilibrium. We also compared our data with previously published population data of other ethnics or areas. The results are valuable for human identification and paternity testing in Chinese Han population.

[Construction and identification of bait recombinant vector of pGBKT7-tumor necrosis factor-alpha converting enzyme cytoplasmic tail in the yeast two-hybrid system].

OBJECTIVE: To construct the bait vector pGBKT7-TACEc (cytoplasmic tail of tumor necrosis factor-alpha converting enzyme) of Macthmaker GAL4 Two-hybrid System 3, and to test whether it has self-activation and toxic action. METHODS: TACEc gene was amplified by RT-PCR from the mouse testis, and the EcoRI and BamHI sites were introduced into it. The TACEc gene, after sequenced, was cloned into pGBKT7. Self-activation and toxic action of the recombination vector pGBKT7-TACEc was tested. RESULTS: The pGBKT7-TACEc vector was successfully constructed and proved of no self-activation and toxic action. CONCLUSION: The pGBKT7-TACEc can be applied to the screening of the mouse testis cDNA library in the yeast two-hybrid system.

[PDCD5 induces the apoptosis of human prostate cancer cells PC-3M-1E8].

OBJECTIVE: To investigate the apoptosis-promoting effect of PDCD5 on human prostate cancer cells PC-3M-1E8. METHODS: PCI-neo and PCI-neo-PDCD5 were transfected into PC-3M-1E8 cells by Lipofectamine 2000, the viability of the cells was analyzed by MTT assay 16 hours after removal of the serum, and the apoptosis was determined by in situ end-labeling and electron microscopy. RESULTS: The viability and growing speed of the transfected cells were significantly decreased and their apoptotic indexes significantly increased as compared with the control group (P < 0.001). CONCLUSION: PDCD5 may significantly inhibit the in vitro growth and promote the apoptosis of human prostate cancer cells PC-3M-1E8.

[Effects of interferon-gamma and tumor necrosis factor-alpha on the fertilizing capacity of human sperm and their mechanisms].

OBJECTIVE: To investigate the effects of interferon-gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-gamma) on the sperm acrosin activity and the rate of acrosome reaction and to probe into their mechanisms. METHODS: Thirty-six nearly normal semen samples were treated with IFN-gamma and/or TNF-alpha after isolated by 75% Percoll. The sperm acrosin activity was tested by the method of BAEE/ADH Unity, the rate of acrosome reaction observed by Triple-stain technique, the NO concentration measured by HPLC and the activities of Na+ -K+ -ATPase, Ca2+ -ATPase and SOD assayed by kit method. RESULTS: Both IFN-gamma and TNF-gamma could decrease sperm acrosin activity and acrosome reaction (P < 0.05 or P < 0.01). TNF-alpha showed stronger inhibiting effect, IFN-gamma markedly reduced the activities of Na+ -K+ -ATPase, Ca2+ -ATPase and SOD in sperm (P < 0.01), and their synergistic action was weaker. However TNF-alpha produced hardly any effect on Na+ -K+ -ATPase and Ca2+ -ATPase. The NO concentration in sperm was significantly increased by IFN-gamma and/or TNF-alpha (P < 0.01). CONCLUSION: IFN-gamma and TNF-alpha have some inhibiting effect on sperm acrosin activity and the rate of acrosome reaction, which could be attributed to their influence on the activities of Na+ -K+ -ATPase, Ca2+ -ATPase and SOD, the NO concentration and so on.

A wearable strain sensor based on a carbonized nano-sponge/silicone composite for human motion detection.

Melamine sponge, also known as nano-sponge, is widely used as an abrasive cleaner in our daily life. In this work, the fabrication of a wearable strain sensor for human motion detection is first demonstrated with a commercially available nano-sponge as a starting material. The key resistance sensitive material in the wearable strain sensor is obtained by the encapsulation of a carbonized nano-sponge (CNS) with silicone resin. The as-fabricated CNS/silicone sensor is highly sensitive to strain with a maximum gauge factor of 18.42. In addition, the CNS/silicone sensor exhibits a fast and reliable response to various cyclic loading within a strain range of 0-15% and a loading frequency range of 0.01-1 Hz. Finally, the CNS/silicone sensor as a wearable device for human motion detection including joint motion, eye blinking, blood pulse and breathing is demonstrated by attaching the sensor to the corresponding parts of the human body. In consideration of the simple fabrication technique, low material cost and excellent strain sensing performance, the CNS/silicone sensor is believed to have great potential in the next-generation of wearable devices for human motion detection.

Expression and location of Smad2, 4 mRNAs during and after liver fibrogenesis of rats.

AIM: To investigate the location alteration of Smad2 and Smad4 mRNAs in the liver during and after fibrogenesis in rats. METHODS: Eighty male Wistar rats weighing approximately 200 g each were used. The rat models of experimental hepatic fibrosis were established by injection with carbon tetrachloride (CCl4), normal rats and rats were injected with olive oil and served as control groups. In situ hybridization(ISH) was used to detect the Smad2 and Smad4 mRNA in liver. RESULTS: In situ hybridization showed Smad2 and Smad4 mRNA expressions in the cytoplasm of hepatic stellate cells (HSC), fibroblasts and myofibroblasts around the central vein and hepatic sinus during and after fibrogenesis. Expression of Smad2, 4 mRNA was higher than that in normal and control rats. CONCLUSION: In the process of and after hepatic fibrosis formation, HSC, fibroblasts and myofibroblasts are the major cells that express Smad2 and Smad4. The more serious the hepatic fibrosis is in the injured liver, the higher the level of Smad2 and Smad4 gene expression is during and after fibrogenesis respectively.

[Evaluation of hemodynamic changes by digital subtraction angiography after treatment of avascular osteonecrosis of femoral head with vascularized bone flaps].

OBJECTIVE: To evaluate the effect of digital subtraction angiography (DSA) in evaluation of the hemodynamic changes after treatment of avascular osteonecrosis of femoral head with vascularized bone flaps. METHODS: Fifty-four patients, 33 males and 21 females, 33 hips being at the stage II and 21 hips being at the stage III, were treated with vascularized bone flaps, including iliac bone flaps pedicled with ascending branch of lateral femoral circumflex artery for 23 hips, greater trochanter bone flaps pedicled with gluteal muscle branch of ascending branch of lateral femoral circumflex artery for 13 hips, greater trochanter bone flaps pedicled with transverse branch of ascending branch of lateral femoral circumflex artery for 9 hips, and greater trochanter bone flaps pedicled with gluteal muscle branch and transverse branch of ascending branch of lateral femoral circumflex artery for 9 hips. Selective DSA was performed on all 54 patients pre-operatively and on 19 patients 6-24 months post-operatively. RESULTS: DSA before operation demonstrated abnormal vascularization in all 54 patients. Six months after operation reconstruction of blood supply on the femoral head was seen in 48 cases. Six patients showed poor filling or failure of filling of the vessel pedicles in transplanted bone flaps 6 months post-operatively and DSA conducted 8 months postoperatively showed satisfactory filling in one of the 6 cases. The clinical success rate of this group was 91%, and the radiological success rate was 85%. CONCLUSION: Selective DSA is effective in evaluation of the postoperative hemodynamic changes in the necrotic femoral head. Significant blood supply in the bone flap is the key point in the success of treatment of ONFH.

Multifunctional Wearable Device Based on Flexible and Conductive Carbon Sponge/Polydimethylsiloxane Composite.

Wearable devices that can be used to monitor personal health, track human motions, and provide thermotherapy, etc., are highly desired in personalized healthcare. In this work, a multifunctional wearable "wrist band" which works as both heater for thermotherapy and sensor for personal health and motion monitoring is fabricated from a flexible and conductive carbon sponge/polydimethylsiloxane (CS/PDMS) composite. The key functional material of the wrist band, namely, the conductive CS, is synthesized from waste paper by a freeze-drying and high-temperature pyrolysis process. When the wrist band works as a heater under 15 V, a stable temperature difference of 20 °C is achieved between the wrist band and the ambient. When the wrist band serves as a wearable strain sensor, the wrist band exhibits fast and repeatable response and excellent durability within the strain range of 0-20% and the working frequency of 0.01-10 Hz. Finally, the typical applications of the multifunctional wearable wrist band, as a heater for thermotherapy and a sensor for blood pulse, breathe, and walk monitoring, are demonstrated. Due to its low cost, high flexibility, moderate conductivity, and excellent strain sensibility, the as-prepared wearable device based on the CS/PDMS composite is promising to be applied for the provision of personal healthcare.

Role of RbBP5 and H3K4me3 in the vicinity of Snail transcription start site during epithelial-mesenchymal transition in prostate cancer cell.

EMT (epithelial-mesenchymal transition) occurs in a wide range of tumor types, and has been shown to be crucial for metastasis. Epigenetic modifications of histones contribute to chromatin structure and result in the alterations in gene expression. Tri-methylation of histone H3 lysine 4 (H3K4me3) is associated with the promoters of actively transcribed genes and can serve as a transcriptional on/off switch. RbBP5 is a component of the COMPASS/ -like complex, which catalyzes H3K4me3 formation. In this study, we found that in the process of TGF-Beta1 induced EMT in the prostate cancer cell line DU145, H3K4me3 enrichment and RbBP5 binding increased in the vicinity of Snail (SNAI1) transcription start site. Knocking-down of RbBP5 notably decreased Snail expression and EMT. Recruitment of RbBP5 and formation of H3K4me3 at Snail TSS during EMT depend on binding of SMAD2/3 and CBP at Snail TSS. This study links the SMAD2/3 signal with Snail transcription via a histone modification - H3K4me3. Furthermore, our research also demonstrates that RbBP5 and even WRAD may be a promising therapeutic candidates in treating prostate cancer metastasis, and that DU145 cells maintain their incomplete mesenchymal state in an auto/ paracrine manner.

[Conservative methods for osteonecrosis of the femoral head: the review of 1005 cases].

OBJECTIVE: To research on the conservative methods used to preserve the femoral head of patients with osteonecrosis of the femoral head. METHODS: In these series surgical procedures the osteonecrotic lesion was removed and various vascularized bone blocks or periosteal flaps with its nutrient vessels were transferred to regain sphericity of the femoral head and reinforce the sequestrum. The current study assessed 1005 patients (1226 hips) operated on from 1989 to 2002 with an average follow-up of 5.1 years (range, 1.5-15 years). The mean age of the patients was 37.4 years (range, 17-65 years). RESULTS: Sixty-one hips (57 patients) had conversion surgery to a total hip arthroplasty because of progressive collapse or severe pain, or both. In the patients without failure, postoperative Harris hip score improved significantly. Of the 1174 reconstructions that were in situ, 1041 (89.4%) were clinically successful, and 878 (75.4%) were radiologically successful. In relation to the stage of necrosis according to the classification system of Ficat and Alert, good results were achieved in 95.3% of the patients with stages II disease, 87.9% with stages III and 60.8% with stages IV. CONCLUSIONS: Conservative methods of vascularized bone block or periosteal flap transfer should be considered in active symptomatic patients to preserve the femoral head. In addition, the earlier the stages of the disease the better outcome could be obtained.

DNA methylation inhibitor, decitabine, promotes MGC803 gastric cancer cell migration and invasion via the upregulation of NEDD4­1.

Gastric cancer is the fourth most common cancer type and the second leading cause of cancer­associated mortality worldwide. Metastasis is a crucial feature of its progression. DNA methylation provides a key epigenetic signature in the epigenetic regulation pathway, and is implicated in transcriptional regulation. CpG sites, which are associated with gene transcriptional activity, are underrepresented in the mammalian genome and tend to be clustered within CpG islands (CGIs) located in the vicinity of the transcription start sites of the majority of the protein­coding genes in humans. The DNA methylation inhibitor, decitabine (DAC), has been demonstrated to be active in hematological disorders. The majority of previous studies in cancer cells demonstrated that DAC inhibits cell proliferation and the motility of the cells. However, since demethylation across the entire genome alters the expression of a large number of genes, the effects of DAC in different tumor cell types are difficult to accurately predict. Neural precursor cell­expressed, developmentally downregulated (NEDD)4­1, a member of the NEDD4 family, which belongs to the E3­ubiquitin ligase family, was reported to be highly expressed in a wide range of tumor types, and it activates the phosphoinositide 3­kinase/Akt pathway by degrading phosphatase and tensin homolog. NEDD4­1 promotes the migration and invasion of glioma cells via the ubiquitination and subsequent degradation of cyclic nucleotide­Ras guanine nucleotide exchange factors (CNrasGEFs). In gastric cardia adenocarcinoma, NEDD4­1 acts as an exceptional prognostic biomarker. In the present study, DAC was revealed to promote the invasive properties of MGC803 gastric cancer cells. NEDD4­1 targeted the CNrasGEF­mediated DAC invasion­promoting activity in MGC803 cells, and CGI methylation in neither the NEDD4 promoter nor the first intron was demonstrated to be associated with this effect. The results of the present study revealed that DAC exerts variable effects in different gastric cancer cell lines and may provide a reference for DAC administration in the clinic.