ABSTRACT
Objective:To evaluate the effect of down-regulation of Sp1 expression on the radiosensitivity of glioma cells.Methods:The oligonucleotide sequence encoding shRNA was designed and synthesized, and cloned into LV3 (H1/GFP & Puro) vector to construct the recombinant. U251 and U87 cells were infected with recombinant lentivirus, then the stably-transfected cell lines were obtained by puromycin screening. The expression levels of Sp1 mRNA and protein were detected by RT-PCR and Western blot. Cell survival was detected by clonal survival assay, cell cycle was determined by flow cytometry, and DNA damage was measured by immunofluorescence assay, respectively.Results:At 72 h after infection, high expression of Sp1 lentiviral vector was observed in two cell lines under fluorescence microscope. RT-PCR and Western blot confirmed that the expression levels of Sp1 mRNA and protein were significantly down-regulated in both transfected cells (both P<0.01) and the silencing rates of Sp1 were above 90%. The sensitization enhancement ratio (SER) of shRNA-U251 and shRNA-U87 cells at 10% cell survival level were 1.39 and 1.18, respectively. After irradiation, the G 2/M phase ratio and the number of γ-H2AX foci in two Sp1 knockout groups were significantly increased. Conclusion:shRNA silencing of Sp1 increases the G 2/M phase arrest induced by X-ray, aggravates the degree of DNA double-strand breaks, and improves the radiosensitivity of glioma cells.
ABSTRACT
N6-methyladenosine (m6A) methylation modification is one of the most common epigenetic modifications for eukaryotic mRNA. Under the catalytic regulation of relevant enzymes, m6A participates in the body's pathophysiological processes via mediating RNA transcription, splicing, translation, and decay. In the past, we mainly focused on the regulation of m6A in tumors such as hematological tumors, cervical cancer, breast cancer. In recent years, it has been found that m6A is enriched in mRNAs of neurogenesis, cell cycle, and neuron differentiation. Its regulation in the nervous system is gradually being recognized. When the level of m6A modification and the expression levels of relevant enzyme proteins are changed, it will cause neurological dysfunction and participate in the occurrence and conversion of neurological diseases. Recent studies have found that the m6A modification and its associated enzymes were involved in major depressive disorder, Parkinson's disease, Alzheimer's disease, Fragile X syndrome, amyotrophic lateral sclerosis, and traumatic brain injury, and they also play a key role in the development of neurological diseases and many other neurological diseases. This paper mainly reviewed the recent progress of m6A modification-related enzymes, focusing on the impact of m6A modification and related enzyme-mediated regulation of gene expression on the central nervous system diseases, so as to provide potential targets for the prevention of neurological diseases.
Subject(s)
Humans , Adenosine/metabolism , Depressive Disorder, Major , Epigenesis, Genetic , Methylation , RNA, Messenger/metabolismABSTRACT
Nucleic acid aptamer is an oligonucleotide sequence screened by the exponential enrichment ligand system evolution technology (SELEX). Previous studies have shown that nucleic acid aptamer has a good application prospect in tumor diagnosis and treatment. Therefore, we reviewed the selection and identification of nucleic acid aptamer of lung cancer cells in recent years, and discussed the effect of aptamer as targeting drugs and targeting vectors on the diagnosis of tumors, which provide a new idea for early diagnosis and treatment of tumor.
ABSTRACT
Aptamers have shown great potential in early diagnosis,treatment of tumor because of its high specificity and affinity.The aptamers selected by cell-SELEX can identify tumor cells through target molecular changes,and then realize the prevention and treatment of tumors.At present,researchers have successfully selected a number of aptamers by using cell-SELEX technology combined with flow cytometry.To make up for the deficiencies and exert the advantages of aptamers can make aptamer technology really apply to clinical diagnosis and treatment.
ABSTRACT
The nucleic acid adapters of tumor serum markers are oligonucleotide molecules with high specificity and high affinity with tumor serum markers obtained by screening with systematic evolution of ligands by exponential enrichment (SELEX). Researchers take the advantage of the nucleic acid adapter to explore new tumor serum markers that have more diagnostic value for tumor diagnosis. Recently, some achievements have been achieved in the research of liver cancer and stomach cancer. This paper has reviewed nucleic acid adapter and its research in the serum tumor marker screening, and discussed the value of the nucleic acid adapter of serum tumor markers in the diagnosis, as well as current problems existing in the research. This paper is very useful to help people better understand the screening of nucleic acid adapters of tumor serum markers, and to provide help in discovering new tumor serum markers.