Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
80
result(s) for
"Zheng, Fengyun"
Sort by:
Characteristic Face: A Key Indicator for Direct Diagnosis of 22q11.2 Deletions in Chinese Velocardiofacial Syndrome Patients
2013
Velocardiofacial syndrome (VCFS) is a disease in human with an expansive phenotypic spectrum and diverse genetic mechanisms mainly associated with copy number variations (CNVs) on 22q11.2 or other chromosomes. However, the correlations between CNVs and phenotypes remain ambiguous. This study aims to analyze the types and sizes of CNVs in VCFS patients, to define whether correlations exist between CNVs and clinical manifestations in Chinese VCFS patients. In total, 55 clinically suspected Chinese VCFS patients and 100 normal controls were detected by multiplex ligation-dependent probe amplification (MLPA). The data from MLPA and all the detailed clinical features of the objects were documented and analyzed. A total of 44 patients (80.0%) were diagnosed with CNVs on 22q11.2. Among them, 43 (78.2%) presented with 22q11.2 heterozygous deletions, of whom 40 (93.0%) had typical 3-Mb deletion, and 3 (7.0%) exhibited proximal 1.5-Mb deletion; no patient was found with atypical deletion on 22q11.2. One patient (1.8%) presented with a 3-Mb duplication mapping to the typical 3-Mb region on 22q11.2, while none of the chromosomal abnormalities in the MLPA kit were found in the other 11 patients and 100 normal controls. All the 43 patients with 22q11.2 deletions displayed characteristic face and palatal anomalies; 37 of them (86.0%) had cognitive or behavioral disorders, and 23 (53.5%) suffered from immune deficiencies; 10 patients (23.3%) manifested congenital heart diseases. Interestingly, all patients with the characteristic face had 22q11.2 heterozygous deletions, but no difference in phenotypic spectrum was observed between 3-Mb and 1.5-Mb deletions. Our data suggest that the characteristic face can be used as a key indicator for direct diagnosis of 22q11.2 deletions in Chinese VCFS patients.
Journal Article
miRNA-135a promotes breast cancer cell migration and invasion by targeting HOXA10
2012
Background
miRNAs are a group of small RNA molecules regulating target genes by inducing mRNA degradation or translational repression. Aberrant expression of miRNAs correlates with various cancers. Although miR-135a has been implicated in several other cancers, its role in breast cancer is unknown.
HOXA10
however, is associated with multiple cancer types and was recently shown to induce p53 expression in breast cancer cells and reduce their invasive ability. Because
HOXA10
is a confirmed miR-135a target in more than one tissue, we examined miR-135a levels in relation to breast cancer phenotypes to determine if miR-135a plays role in this cancer type.
Methods
Expression levels of miR-135a in tissues and cells were determined by poly (A)-RT PCR. The effect of miR-135a on proliferation was evaluated by CCK8 assay, cell migration and invasion were evaluated by transwell migration and invasion assays, and target protein expression was determined by western blotting. GFP and luciferase reporter plasmids were constructed to confirm the action of miR-135a on downstream target genes including
HOXA10
. Results are reported as means ± S.D. and differences were tested for significance using 2-sided Student\"s t-test.
Results
Here we report that miR-135a was highly expressed in metastatic breast tumors. We found that the expression of miR-135a was required for the migration and invasion of breast cancer cells, but not their proliferation.
HOXA10
, which encodes a transcription factor required for embryonic development and is a metastasis suppressor in breast cancer, was shown to be a direct target of miR-135a in breast cancer cells. Our analysis showed that miR-135a suppressed the expression of
HOXA10
both at the mRNA and protein level, and its ability to promote cellular migration and invasion was partially reversed by overexpression of
HOXA10
.
Conclusions
In summary, our results indicate that miR-135a is an onco-miRNA that can promote breast cancer cell migration and invasion.
HOXA10
is a target gene for miR-135a in breast cancer cells and overexpression of
HOXA10
can partially reverse the miR-135a invasive phenotype.
Journal Article
WWC1/2 regulate spinogenesis and cognition in mice by stabilizing AMOT
WWC1 regulates episodic learning and memory, and genetic nucleotide polymorphism of
WWC1
is associated with neurodegenerative diseases such as Alzheimer’s disease. However, the molecular mechanism through which WWC1 regulates neuronal function has not been fully elucidated. Here, we show that WWC1 and its paralogs (WWC2/3) bind directly to angiomotin (AMOT) family proteins (Motins), and recruit USP9X to deubiquitinate and stabilize Motins. Deletion of
WWC
genes in different cell types leads to reduced protein levels of Motins. In mice, neuron-specific deletion of
Wwc1
and
Wwc2
results in reduced expression of Motins and lower density of dendritic spines in the cortex and hippocampus, in association with impaired cognitive functions such as memory and learning. Interestingly, ectopic expression of AMOT partially rescues the neuronal phenotypes associated with
Wwc1/2
deletion. Thus, WWC proteins modulate spinogenesis and cognition, at least in part, by regulating the protein stability of Motins.
Journal Article
Fast Focal Point Correction in Prism-Coupled Total Internal Reflection Scanning Imager Using an Electronically Tunable Lens
by
Mi, Lan
,
Wang, Xu
,
Zheng, Fengyun
in
electronically tunable lens
,
focal point correction
,
Geometry
2018
Total internal reflection (TIR) is useful for interrogating physical and chemical processes that occur at the interface between two transparent media. Yet prism-coupled TIR imaging microscopes suffer from limited sensing areas due to the fact that the interface (the object plane) is not perpendicular to the optical axis of the microscope. In this paper, we show that an electrically tunable lens can be used to rapidly and reproducibly correct the focal length of an oblique-incidence scanning microscope (OI-RD) in a prism-coupled TIR geometry. We demonstrate the performance of such a correction by acquiring an image of a protein microarray over a scan area of 4 cm2 with an effective resolution of less than 20 microns. The electronic focal length tuning eliminates the mechanical movement of the illumination lens in the scanning microscope and in turn the noise and background drift associated with the motion.
Journal Article
ZNF191 alters DNA methylation and activates the PI3K‐AKT pathway in hepatoma cells via transcriptional regulation of DNMT1
by
Zhang, Pingzhao
,
Liu, Xiuping
,
Cheng, Hanghang
in
1-Phosphatidylinositol 3-kinase
,
AKT protein
,
Carcinoma, Hepatocellular - pathology
2022
Background Alteration of DNA methylation is an important event in pathogenesis and progression of hepatocellular carcinoma (HCC). DNA methyltransferase (DNMT) 1, the foremost contributor in DNA methylation machinery, was revealed elevated in HCC and significantly correlates with poor prognosis. However, the transcriptional regulation of DNMT1 in HCC remains unknown. Methods Real‐time PCR and immunohistochemistry were performed to detect DNMT1 and zinc finger transcription factor 191 (ZNF191) expressions in HCCs. Transcription activity of DNMT1promoter was analyzed with Luciferase reporter activity assay. The binding capacity of ZNF191 protein to DNMT1 promoter was examined with chromatin immunoprecipitation‐qPCR (ChIP‐qPCR) and electrophoretic mobility shift assay (EMSA). DNA methylation level of hepatoma cells was detected with Methylation array. Results ZNF191 can regulate DNMT1 mRNA and protein expression positively, and increase the transcription activity of the DNMT1 promoter. ChIP‐qPCR and EMSA revealed that ZNF191 protein directly binds to the DNMT1 promoter at nt‐240 AT(TCAT)3TC. Moreover, DNMT1 and ZNF191 expression correlate positively in human HCCs. With methylation array, DNA methylation alteration was observed in hepatoma cells with ZNF191 knockdown, and the differential methylation sites are enriched in the PI3K‐AKT pathway. Furthermore, we proved DNMT1 contributes the effect of ZNF191 on hepatoma cell growth via the PI3K‐AKT pathway. Conclusion ZNF191 is a novel transcription regulator for DNMT1, and the pro‐proliferation effect of ZNF191/DNMT1/p‐AKT axis in hepatoma cells implies that ZNF191 status in HCCs may affect the therapeutic effect of DNMTs inhibitors and PI3K inhibitors for precise treatment of the disease. ZNF191 directly binds to DNMT1 promoter, and transactivates the DNMT1 gene. ZNF191 alters DNA methylation in hepatoma cells with DMS enriched in the PI3K‐AKT pathway. DNMT1 contributes the effect of ZNF191 on HCC cell growth via the PI3K‐AKT pathway.
Journal Article
Developing an Efficient and General Strategy for Immobilization of Small Molecules onto Microarrays Using Isocyanate Chemistry
by
Li, Quanfu
,
Dang, Yongjun
,
Mi, Lan
in
Drug Discovery
,
Glass - chemistry
,
high-throughput screening
2016
Small-molecule microarray (SMM) is an effective platform for identifying lead compounds from large collections of small molecules in drug discovery, and efficient immobilization of molecular compounds is a pre-requisite for the success of such a platform. On an isocyanate functionalized surface, we studied the dependence of immobilization efficiency on chemical residues on molecular compounds, terminal residues on isocyanate functionalized surface, lengths of spacer molecules, and post-printing treatment conditions, and we identified a set of optimized conditions that enable us to immobilize small molecules with significantly improved efficiencies, particularly for those molecules with carboxylic acid residues that are known to have low isocyanate reactivity. We fabricated microarrays of 3375 bioactive compounds on isocyanate functionalized glass slides under these optimized conditions and confirmed that immobilization percentage is over 73%.
Journal Article
PolyA RT-PCR-based quantification of microRNA by using universal TaqMan probe
2012
Quantification of microRNAs (miRNAs) in tissues under normal and pathological conditions is important for elucidating miRNA functions. Based on a PolyA RT-PCR method we have described (J Zhang et al. Biochem Biophys Res Commun 2008 377:136–140), a modified miRNA quantification method was developed and validated using a universal TaqMan probe complementary to the reverse transcript primer. This method effectively detects miRNA expression in cell lines and tissues. The TaqMan probe is more accurate and reliable than the SYBR Green method since it was free from primer dimers. A series of miRNAs were tested in five different mouse tissues: the method differentiated different miRNAs of the same family. This universal TaqMan probe-based PolyA RT-PCR method showed its advantages in precision, simplicity and high-throughput capability compared with other miRNA-detecting methods.
Journal Article
LINE-1 methylation status and its association with tetralogy of fallot in infants
by
Ma, Xiaojing
,
Wu, Yao
,
Wang, Huijun
in
Basic Helix-Loop-Helix Transcription Factors - genetics
,
Biomedical and Life Sciences
,
Biomedicine
2012
Background
Methylation levels of long interspersed nucleotide elements (LINE-1) are representative of genome-wide methylation status and play an important role in maintaining genomic stability and gene expression. To derive insight into the association between genome-wide methylation status and tetralogy of fallot (TOF), we compared the methylation status of LINE-1 element between TOF patients and controls. The methylation of the
NKX
2
–
5,
HAND
1, and
TBX
20 promoter regions was also evaluated.
Methods
Genomic DNA from right ventricular tissue samples was obtained from 32 patients with TOF and 15 control subjects. Sequenom MassARRAY platform was performed to examine the methylation levels of LINE-1,
NKX
2-5,
HAND
1 and
TBX
20. Mann–Whitney U test was used to compare differences in methylation levels between two groups.
Results
The methylation level of LINE-1 was significantly lower in patients with TOF, with a median of 57.95% (interquartile range [IQR]: 56.10%–60.04%), as opposed to 59.70% in controls (IQR: 59.00%–61.30%;
P
= 0.0021). The highest LINE-1 methylation level was 61.3%. The risk of TOF increased in subjects with the lowest methylation levels (less than or equal to 59.0%; OR = 14.7, 95% CI: 1.8–117.7,
P
= 0.014) and in those with medium methylation levels (59.0%–61.3%; OR = 2.0, 95% CI: 0.3–14.2,
P
= 0.65). An ROC curve analysis showed a relatively high accuracy of using the LINE-1 methylation level in predicting the presence of TOF (AUC = 0.78, 95% CI: 0.65–0.91;
P
= 0.002). The association of the LINE-1 methylation level with TOF was only observed in males (
P
= 0.006) and not in females (
P
= 0.25). Neither age nor gender was found to be associated with the LINE-1 methylation level in patients or controls. Higher methylation levels of
NKX
2-5 and
HAND
1 and lower methylation levels of
TBX
20 were also observed in patients with TOF than in controls. No association was found between the methylation levels of
NKX
2-5,
HAND
1 and
TBX
20 with the LINE-1 methylation level.
Conclusions
Lower LINE-1 methylation levels are associated with increased risk of TOF and may provide important clues for the development of TOF.
Journal Article
Low expression of TFPI-2 associated with poor survival outcome in patients with breast cancer
2013
Background
The purpose of this study is to evaluate the prognostic value of TFPI-2 expression in breast cancer patients through examining the correlation between TFPI-2 expression and breast cancer clinicopathologic features.
Methods
Immunohistochemical staining combined with digital image analysis was used to quantify the expression of TFPI-2 protein in breast tumor tissues. For evaluation of the prognostic value of TFPI-2 expression to each clinicopathologic factor, Kaplan-Meier method and COX’s Proportional Hazard Model were employed.
Results
TFPI-2 expression was significantly correlated with tumor size, lymph node metastasis, histologic grade, clinical stage, and vessel invasion. More importantly, TFPI-2 expression was also associated with disease-free survival (DFS) of breast cancer patients. We found that patients with high TFPI-2 expression had longer DFS compared with those with low or negative expression of TFPI-2 (
P
<0.05, log-rank test). Cox’s regression analysis indicated that TFPI-2 expression, histologic grade, and vessel invasion might be significant prognostic factors for DFS, while TFPI-2 expression and histologic grade were the most significant independent predictors for tumor recurrence. Compared with the group with low/high TFPI-2 expression, the TFPI-2 negative group was more likely to have tumor relapse. The hazard ratio of DFS is 0.316 (
P
<0.01).
Conclusions
Low or negative expression of TFPI-2 is associated with breast cancer progression, recurrence and poor survival outcome after breast cancer surgery. TFPI-2 expression in breast tumors is a potential prognostic tool for breast cancer patients.
Journal Article
Current Lightning Risk Assessment in Yantai
2014
The development situation and business processes of lightning risk assessment in Yantai were summarized and analyzed to provide references for the operation of lighting risk assessment. This study aimed to further improve lightning risk assessment and promote the development of lightning risk assessment through practice and discussion.
Journal Article