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Huijie Sun

Publications and source records attributed to Huijie Sun.

3 recordsLinked to original sources

MicroRNA‑27a promotes tumorigenesis via targeting AKT in triple negative breast cancer.

Altered microRNA (miRNA/miR) expression regulates tumor development and progression in triple‑negative breast cancer (TNBC). The present study examined the effect of miR‑27a on proliferation, migration and invasion of TNBC cells in vitro and in vivo. An MTT assay was performed to examine the proliferation of MDA‑MB‑231 and MDA‑MB‑468 breast cancer cells with either overexpression of miR‑27a or downregulation of miR‑27a, in the presence or absence of radiation. The migratory and invasive abilities of MDA‑MB‑231 and MDA‑MB‑468 breast cancer cells were assessed by Transwell migration and Matrigel invasion assays. The protein expression levels were examined by western blotting. The caspase‑Glo3/7 assay was performed to examine the effect of miR‑27a on radiation‑induced apoptosis in MDA‑MB‑231 and MDA‑MB‑468 breast cancer cells. A luciferase assay was performed to evaluate the effect of miR‑27a on phosphatase and tensin homolog (PTEN) and B cell lymphoma (Bcl)‑2 associated X, apoptosis regulator (BAX) expression. Immunodeficient nude mice were used to examine tumor growth following injection of MDA‑MB‑231 breast cancer cells. miR‑27a promoted proliferation in vitro and in vivo, and enhanced migration and invasion in TNBC cells. miR‑27a improved the survival of TNBC cells following irradiation. miR‑27a inhibited radiation‑induced apoptosis in TNBC cells by regulation of caspase 3/7 and Bcl‑2 expression. Furthermore, the expression levels of PTEN and phosphorylated protein kinase B in MDA‑MB‑231 and MDA‑MB‑468 cells was altered following overexpression of miR‑27a. The luciferase assay demonstrated that miR‑27a regulated PTEN and BAX expression by binding to 3'‑untranslated regions. Overall, miR‑27a exhibits an essential role in tumor development and progression in TNBC and may be used as a potential biomarker to predict radiotherapy response and prognosis for the disease.

3' Untranslated Regions↗

Prevalence of neutralizing antibodies to adenoviral serotypes 5 and 35 in the adult populations of The Gambia, South Africa, and the United States.

One of the major limitations of the use of adenoviruses as gene therapy vectors is the existence of preformed immunity in various populations. Recent studies have linked failure of adenoviral gene therapy trials to the presence of antiadenoviral neutralizing antibodies (NAb). Understanding the distribution and specificity of such antibodies will assist in the design of successful recombinant adenoviral gene therapies and vaccines. To assess the prevalence of NAb to adenovirus serotypes 5 and 35 (Ad5 and Ad35), we analyzed serum samples from adult immunocompetent individuals living in The Gambia, South Africa, and the United States by using a neutralization assay. Serum samples were incubated with A549 lung carcinoma cells and adenoviruses encoding enhanced green or yellow fluorescent proteins; results were analyzed by fluorescence microscopy and flow cytometry. Using this technique, we found a high prevalence of NAb against Ad5 in Gambian, South African, and U.S. subjects at both low and high titers. Conversely, all subjects displayed a low prevalence of NAb to Ad35; when present, anti-Ad35 NAb were seen at low titers. Because of the ability of adenoviruses to elicit systemic and mucosal immune responses, Ad35 with its low NAb prevalence appears to be an attractive candidate vector for gene therapy applications.

Adenoviridae↗

UpGene: Application of a web-based DNA codon optimization algorithm.

Although DNA codon optimization is a standard molecular biology strategy to overcome poor gene expression, to date no public software exists to facilitate this process. Among the uses of codon optimization, human immunodeficiency virus (HIV) vaccine development represents one of the most difficult challenges. A key obstacle to an effective DNA-based vaccine is the low-level expression of HIV genes in mammalian cells, which is due primarily to the instability of HIV mRNAs resulting from AU-rich elements and rare codon usage. In this report we describe the development of a DNA optimization algorithm integrated with a PCR primer design program to redesign specific coding sequences for maximal gene expression. Using this algorithm combination, together with PCR-based gene assembly, we have successfully optimized gene sequences for simian immunodeficiency virus (SIV) strain mac239 structural antigenic proteins gag and env, resulting in high-level gene expression in eukaryotic cells. Our findings demonstrate that our user-friendly algorithm is a valuable tool for DNA-based HIV vaccine development. Moreover, it can be used to optimize any other genes of interest and is freely available online at http://www.vectorcore.pitt.edu/upgene.html.

Algorithms↗