Roles of PTBP1 in alternative splicing, glycolysis, and oncogensis.

Polypyrimidine tract-binding protein 1 (PTBP1) plays an essential role in splicing and is expressed in almost all cell types in humans, unlike the other proteins of the PTBP family. PTBP1 mediates several cellular processes in certain types of cells, including the growth and differentiation of neuronal cells and activation of immune cells. Its function is regulated by various molecules, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and RNA-binding proteins.

The regulatory network of nasopharyngeal carcinoma metastasis with a focus on EBV, lncRNAs and miRNAs.

Metastasis of nasopharyngeal carcinoma (NPC) remains a main cause of death for NPC patients even though great advances have been made in therapeutic approaches. An in-depth study into the molecular mechanisms of NPC metastasis will help us combat NPC. Epstein-Barr virus (EBV) infection is an evident feature of nonkeratinizing NPC and is strongly associated with tumor metastasis.

FMNL1 mediates nasopharyngeal carcinoma cell aggressiveness by epigenetically upregulating MTA1.

It has been suggested that formin-like protein 1 (FMNL1) plays an important role in the pathogenic process of several hematopoietic malignancies. In this study, we performed a series of in vivo and in vitro assays to elucidate the biological functions of FMNL1 and underlying mechanisms in human nasopharyngeal carcinoma (NPC) pathogenesis. Herein, we report that high expression of FMNL1 in NPC is positively associated with an aggressive disease and/or poor patient survival.

Research Progress on Reversing Multidrug Resistance in Tumors by Using Chinese Medicine.

Multidrug resistance (MDR) is a major cause of cancer chemotherapy failure, and it is important to develop suitable reversal agents to overcome MDR. A majority of chemical reversal agents have acceptable reversal effects. However, the toxicity and adverse reactions associated with these agents restricts their clinical use.

Roles of flotillins in tumors.

The identification and use of molecular biomarkers have greatly improved the diagnosis and treatment of malignant tumors. However, a much deeper understanding of oncogenic proteins is needed for the benefit to cancer patients. The lipid raft marker proteins, flotillin-1 and flotillin-2, were first found in goldfish retinal ganglion cells during axon regeneration.

The clinicopathological significance of miR-149 and PARP-2 in hepatocellular carcinoma and their roles in chemo/radiotherapy.

Hepatocellular carcinomas (HCC) are commonly diagnosed at an advanced stage with unresectable tumors. Although numerous non-surgical approaches have been developed to treat HCC, the prognosis of patients with HCC is still poor. This study investigated the expression of miR-149 and PARP-2 in HCC tumor tissues and their roles in sensitizing chemo/radiotherapy.

ALDH1 expression is correlated with pathologic grade and poor clinical outcome in patients with astrocytoma.

Aldehyde dehydrogenase 1 (ALDH1), a detoxifying enzyme, is a stem-like cell marker, but its expression pattern and clinical significance in astrocytoma remain unclear. In this study, we used immunohistochemical analysis to systematically investigate the expression of ALDH1 in 76 astrocytomas of different pathological grade and seven samples of normal brain tissues. We found that ALDH1 was expressed in some of the astrocytomas but was not detected in normal brain tissues.

Preparation of human scFv antibody against nasopharyngeal carcinoma and identification of its specificity.

Unlabelled: Abstract Conclusion: The selected scFv antibody could specifically recognize and target nasopharyngeal carcinoma (NPC), and could be applied to clinical diagnosis and therapy.

Objective: The aim was to construct and screen fully human anti-NPC single chain Fv fusion phage libraries, and to identify the specificity of the scFv antibody.

Methods: Peripheral blood mononuclear cells of patients with NPC were immunized in vitro by NPC cells and transformed by Epstein-Barr virus.

[Screening and preliminary analysis of the apoptosis- and proliferation-related genes in nasopharyngeal carcinoma].

Unlabelled: To screen and analyze the apoptosis- and proliferation-related genes in human nasopharyngeal carcinoma (NPC).

Methods: According to gene ontology classification, the abnormal expressions of the genes related to cell apoptosis and proliferation were identified in the NPC gene chip data. The cell apoptosis- and proliferation-related genes expressed in each of the 3 stages, as defined by the tree model for the pathogenesis and progression of NPC, were screened, and with literature review, their distribution in the tree model were analyzed.

The DLC-1 -29A/T polymorphism is not associated with nasopharyngeal carcinoma risk in Chinese population.

Deleted in liver cancer-1 (DLC-1), encoding a Rho GTPase-activating protein (GAP), is considered as a promising candidate tumor suppressor gene in nasopharyngeal carcinoma (NPC). The single-nucleotide polymorphism (SNP) -29A/T upstream of ATG start codon was found when gene mutation profile of DLC-1 in NPC was analyzed. To evaluate the correlation between SNP -29A/T in the promoter region of DLC-1 gene and risk of NPC, a total of 521 samples from a Chinese population, including 320 healthy individuals and 201 NPC patients, were collected for SNP analysis by PCR-single-strand conformation polymorphism and sequencing.

[PTX1 in nasopharyngeal carcinoma by RNAi technology].

Objective: To explore the expression and the role of PTX1 located at the amplified 12p12-p11 region in nasopharyngeal carcinoma (NPC).

Methods: Semi-quantitative RT-PCR and real-time RT-PCR were applied to detect the expression level of PTX1 in 36 NPC and 8 chronic nasopharyngitis (NP) biopsies. RNAi vector targeting PTX1 was constructed and transfected into NPC cell line 6-10B.

Genetic and epigenetic alterations of LTF at 3p21.3 in nasopharyngeal carcinoma.

To investigate the roles of lactotransferrin gene (LTF, also referred to as the lactoferrin gene, LF), located at 3p21.3 within the common minimal deletion region, in the pathogenesis of nasopharyngeal carcinoma (NPC), we first detected its expression level in 33 primary NPC tissues and 15 chronic nasopharyngitis tissues. Absent expression or downregulation of LTF were observed in 76% (25 of 33) of primary NPC tissues.

[Expression, loss of heterozygosity, and methylation of GNAT1 gene in nasopharyngeal carcinoma].

Background & Objective: In nasopharyngeal carcinoma (NPC), chromosome 3p21.3 is a high frequency deletion region. Evidences from both loss of heterozygosity (LOH) and functional studies showed that there may exists NPC-related tumor suppressor genes on 3p21.

Identification of genes related to nasopharyngeal carcinoma with the help of pathway-based networks.

cDNA microarray is a powerful tool to analyze simultaneously the expression levels of tens of thousands of genes. Compared with normal nasopharynx (NP) tissues, 2210 genes were highly differentially expressed in nasopharyngeal carcinoma (NPC) tissues detected by cDNA microarray. Since signal pathway is widely used to describe the complex relationship between genes, a pathway-based network was constructed to visualize the connection between the genes obtained from microarray data in this report.

Identification of label-retaining cells in nasopharyngeal epithelia and nasopharyngeal carcinoma tissues.

Adult stem cells can be identified by label-retaining cell (LRC) approach based on their ability to retain nucleoside analog, such as bromodeoxyuridine (BrdU). We hypothesized that mouse nasopharynx contains a small population of epithelial stem/progenitor cells that may be detected by the LRC technique. To identify LRCs in mice nasopharyngeal epithelia, neonatal mice were intraperitoneally injected with BrdU twice daily for 3 consecutive days.

Genetic and epigenetic alterations of DLC-1, a candidate tumor suppressor gene, in nasopharyngeal carcinoma.

The DLC-1 gene, located at the human chromosome region 8p22, behaves like a tumor suppressor gene and is frequently deleted in diverse tumors. The deletion of 8p22 is not an uncommon event in nasopharyngeal carcinoma (NPC), therefore we explored the expression levels of the DLC-1 gene in NPCs and NPC cell lines by reverse transcription-polymerase chain reaction. The results showed the mRNA level of DLC-1 was downregulated.

Identification of differentially expressed genes in metastatic and non-metastatic nasopharyngeal carcinoma cells by suppression subtractive hybridization.

Background & Objective: Nasopharyngeal carcinoma (NPC) is an epithelial neoplasm with high occurrence rates in southern China. The disease often metastasizes to regional lymphnodes at a very early stage. Local recurrences and metastasis occur frequently in patients with NPC and are a leading cause of death, despite improvements on treatment modalities.

Reexploring the possible roles of some genes associated with nasopharyngeal carcinoma using microarray-based detection.

In gene expression profiling, nasopharyngeal carcinoma (NPC) 5-8F cells differ from 6-10B cells in terms of their high tumorigenicity and metastatic ability. Differentially expressed genes from the two cell types were analyzed by combining with MILANO (the automatic custom annotation of microarray results which is based on all the available published work in PubMed). The results showed that five genes, including CTSD, P63, CSE1L, BPAG1 and EGR1, have been studied or mentioned in published work on NPC.

[Detection of RNA interference in nasopharyngeal carcinoma cell lines using reporter genes].

Background & Objective: RNA interference (RNAi) technique is now widely used in studies of gene function, signal transduction pathway, and gene therapy because it can effectively and specifically inhibit gene expression. This study was designed to synthesize small interfering RNA (siRNA) by in vitro transcription, and construct retrovirus vectors to express small hairpin RNA (shRNA), detect RNAi in nasopharyngeal carcinoma cell lines, and to develop a RNAi technique platform.

Methods: siRNAs targeting green fluorescent protein (GFP) and luciferase (Luc) were synthesized by in vitro transcription, while shRNAs targeting GFP and Luc were constructed from pSUPER.

Critical role of Cys168 in noggin protein's biological function.

Previous studies have indicated that noggin exerts its neural inducing effect by binding and antagonizing bone morphogenetic protein 4 (BMP4). In order to further clarify the relationship between the structure and the function of noggin, and elucidate the possible mechanism responsible for noggin-BMP4 interaction, we generated three noggin mutants, C168S, C174S and C197S, by using a site-directed mutagenesis method. Ectopic expression of wild-type (WT) noggin, C174S or C197S, in Xenopus animal caps (ACs) by mRNA injection converted the explants (prospective ectoderm) into neural tissue, as indicated by the neural-like morphology and expression of the neural cell adhesion molecule (NCAM) in the ACs.

Establishment of human embryonic stem cell line stably expressing Epstein-Barr virus-encoded nuclear antigen 1.

Human embryonic stem (hES) cells have the capability of unlimited undifferentiated proliferation, yet maintain the potential to form perhaps any cell type in the body. Based on the high efficiency of the Epstein-Barr virus-based episomal vector in introducing exogenous genes of interest into mammalian cells, we applied this system to hES cells, expecting that this would resolve the problem of poor transfection efficiency existing in current hES cell research. Therefore, the first step was to establish EBNA1-positive hES cells.

Suppression of bcl-2 gene by RNA interference increases chemosensitivity to cisplatin in nasopharyngeal carcinoma cell line CNE1.

To explore the effect of suppressing BCL-2 expression using RNA interference (RNAi) technique in nasopharyngeal carcinoma cell line CNE1. CNE1 cell lines stably expressing shRNAs targeted bcl-2 and GL3 gene were established and gene expression inhibition was assessed by Western blotting analysis. The effect of suppressing bcl-2 by RNAi on cell growth was studied, the apoptosis induction and the sensitization of CNE1 cells to cisplatin were quantified by MTT assays and flow cytometry.

Gene Expression Profiles of Human Fetal Nasopharyngeal Tissue.

To study differentially expressed genes in nasopharynx tissues of embryo during development, and to observe the gene changes, total RNAs were respectively extracted from the nasopharynx tissue which came from fetuses of 5, 6, 7, and 8 month, Probes were yielded by reverse transcription and were used to hybridize with the Atlas(TM) human cDNA expression arrays. The results showed that the genes expression profile were distinctly different and different expression levels were found in the same gene during development. Results indicated that gene expression pattern had a character of time-dependence, such as early growth response protein 1 and the cDNA expression array provided a powerful method for studying gene expression profile in a large range of genes.

Differentially Expressed Gene Profiles of hCR2-transfected Mouse Cells before and after EBV Infection and TPA Treatment.

Mouse Atlas(TM) cDNA Expression Arrays were used to analyze cellular gene expression profiles of human complement receptor type II gene (hCR2)-transfected mouse cells before and after EBV infection and TPA treatment, followed by screening differentially expressed genes with Eagle Eye II Image Analysis System. Results indicated that differentially expressed gene prifiles of EBV and TPA treated, hCR2-transfected mouse cells was preliminarily established. This study laid the basis for further research in relerant fields.