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Mao A.,CAS Lanzhou Institute of Modern Physics | Mao A.,Lanzhou University | Mao A.,Institute of Gansu Medical Science Research | Mao A.,University of Chinese Academy of Sciences | And 28 more authors.
Tumor Biology | Year: 2015

miR-449a, a novel tumor suppressor, is deregulated in various malignancies, including prostate cancer. Overexpression of miR-449a induces cell cycle arrest, apoptosis, and senescence, but its role in response to ionizing radiation and underlying molecular mechanism are still unknown. Here, we report that miR-449a enhances radiation-induced G2/M phase arrest and apoptosis through modulating pRb/E2F1 and sensitizes prostate cancer cells to X-ray radiation. In wild-type Rb PC-3 cells, overexpression of miR-449a enhances radiation-induced G2/M arrest and apoptosis and promotes the sensitivity to X-ray radiation. While mutant Rb DU-145 cells are resistant to the X-ray radiation despite in the presence of miR-449a. The cell cycle distribution of DU-145 cells is not significantly altered by miR-449a in the response to ionizing radiation. Furthermore, elevated miR-449a downregulates cell cycle regulator CDC25A and oncogene HDAC1. By targeting genes involved in controlling pRb/E2F1 activity, miR-449a regulates cell cycle progression and apoptosis and consequently enhances the radiosensitivity of PC-3 cells. Thus, miR-449a, as a miRNA component of the Rb pathway, promotes the radiosensitivity of PC-3 cells through regulating pRb/E2F1. © 2015 International Society of Oncology and BioMarkers (ISOBM)

Zhao Q.,CAS Lanzhou Institute of Modern Physics | Zhao Q.,Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province | Zhao Q.,University of Chinese Academy of Sciences | Mao A.,CAS Lanzhou Institute of Modern Physics | And 16 more authors.
Life Sciences | Year: 2016

The phenomenon has raised the concerns about the safety of an extended manned mission into deep space due to the high potential for exposure to high-LET radiation during space missions. Heavy ions such as 56Fe are main radiation sources in deep space, which could pose a significant hazard to space flight crews during and after missions. Since the testis is a radiosensitive organ, which may be susceptible to space radiation-induced changes. In this study, we investigated the effect and potential mechanisms of 56Fe irradiation on mouse testis. Pathological characteristics were measured following whole-body irradiation with 0.5 and 1 Gy 56Fe irradiation. Flow cytometry and terminal dUTP nick end-labeling (TUNEL) were performed to detect apoptotic cells. Western blot was applied to identify potential biomarkers. Immunofluorescence was used to investigate protein localization. We found that pathologic changes and apoptosis cells were significantly higher in 1 Gy group than those in 0 Gy groups. In addition, protein expression and localization studies confirmed Nrf2 was involved in this acute injury. Nrf2 and its target genes HO-1 and NQO1 were up-regulated in the irradiated testis in a dose-dependent manner. Nrf2 may be useful molecular markers in radiation-induced cellular responses and is important for detecting abnormal spermatogenesis following exposure to space radiation. © 2016 Elsevier Inc.

Liao S.,Institute of Gansu Medical Science Research | Liu Y.,Institute of Gansu Medical Science Research | Zeng J.,Northwest Normal University | Li X.,Columbia University | And 10 more authors.
Bioconjugate Chemistry | Year: 2010

In the efforts to explore an aptamer-based approach for target sensing and detection with higher sensitivity and specificity, instead of directly labeling aptamer with fluorophores, we proposed a new strategy by attaching a polymerase chain reaction (PCR) template to an oligonucleotide aptamer selected by systematic evolution of ligands by exponential enrichment (SELEX), so that after aptamer target binding, the template moiety serves as the PCR template in real-time quantitative PCR (RT-PCR), and therefore, the binding event can be reported by the following RT-PCR signals. Using the subtractive SELEX method, the oligonucleotide aptamers specific for the Fc fragment of mouse IgG were selected and subjected to coupling with the PCR dsDNA template by using overlap and the asymmetric extension PCR method. The target binding affinity of the PCR template tethered aptamer has been proven by electrophoretic mobility shift assay (EMSA), and further template tethered aptamer mediated real-time quantitative PCR (A-PCR) was conducted to validate the application for such a template tethered aptamer to be a sensitive probe for IgG detection. The results show that the protocols of A-PCR can detect 10-fold serial dilutions of the target, demonstrating a new mechanism to convert aptamer target binding events to amplified RT-PCR signal, and the feasibility of the PCR template tethered aptamer as a facile, specific, and sensitive target probing and detection is established. This new approach also has potential applications in multiple parallel target detection and analysis in a wide range of research fields. © 2010 American Chemical Society.

Zeng J.,Northwest Normal University | Zeng J.,Key Laboratory of Polymer Materials of Gansu Province | Zhang W.,Northwest Normal University | Liao S.,Institute of Gansu Medical Science Research | And 4 more authors.
Advanced Materials Research | Year: 2011

A polymerization between 1, 4-diaminobenzene (PPD) and acrylic acid catalyzed by Horseradish Perodxidase (HRP) in an water buffer will be described in this article. The effects of the concentration of H2O2, the ratio of the acrylic acid to PPD, the pH of the buffer, and the reaction time of polymerization were investigated. Compared with conventional methods, the synthesis is simple and the conditions are mild. The conductivity, UV-vis spectra, FT-IR spectra, X-ray photoelectron spectroscopy (XPS), and the thermo-gravimetric analysis (TGA) of the resulting polymer were investigated also. The results show that the synthesized polymer (PAnI) is a self-doped poly(1, 4-diaminobenzene-acrylic acid) with 1, 4-disubstituted aromatic ring, and a higher electro-activity, water-solubility, its decomposition temperature is 498.8 °C.

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