Identification and Analysis of SND1 as an Oncogene and Prognostic Biomarker for Lung Adenocarcinoma / 中国肺癌杂志

BACKGROUND@#Transcription factor (TF) can bind specific sequences that either promotes or represses the transcription of target genes, and exerts important effects on tumorigenesis, migration, invasion. Staphylococcal nuclease-containing structural domain 1 (SND1), which is a transcriptional co-activator, is considered as a promising target for tumor therapy. However, its role in lung adenocarcinoma (LUAD) remains unclear. This study aims to explore the role of SND1 in LUAD.@*METHODS@#Data from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Clinical Proteomic Tumor Analysis Consortium (CPTAC), and Human Protein Atlas (HPA) database was obtained to explore the association between SND1 and the prognosis, as well as the immune cell infiltration, and subcellular localization in LUAD tissues. Furthermore, the functional role of SND1 in LUAD was verified in vitro. EdU assay, CCK-8 assay, flow cytometry, scratch assay, Transwell assay and Western blot were performed.@*RESULTS@#SND1 was found to be upregulated and high expression of SND1 is correlated with poor prognosis of LUAD patients. In addition, SND1 was predominantly present in the cytoplasm of LUAD cells. Enrichment analysis showed that SND1 was closely associated with the cell cycle, as well as DNA replication, and chromosome segregation. Immune infiltration analysis showed that SND1 was closely associated with various immune cell populations, including T cells, B cells, cytotoxic cells and dendritic cells. In vitro studies demonstrated that silencing of SND1 inhibited cell proliferation, invasion and migration of LUAD cells. Besides, cell cycle was blocked at G1 phase by down-regulating SND1.@*CONCLUSIONS@#SND1 might be an important prognostic biomarker of LUAD and may promote LUAD cells proliferation and migration.

Analysis of Cellular Stress Response in Two AUG of Human SND1 Gene / 天津医药

Objective To construct eukaryotic Flag (DYKDDDDK) expressing recombinant plasmids, pCMV-N-Flag-SND1-No1/2, which contain the coding sequence of human SND1-No1(from 1st AUG)or SND1-No2 (from 2nd AUG), and perform the cellular localization analysis of Flag-tagged SND1-No1/2 under stress condition to study the function of the two AUG in the SND1 containing stress granules formation. Methods The gene fragments of SND1-No1/2 were amplified by PCR from the whole SND1 transcript and inserted into pCMV-N-Flag expressing vector through BamHI/EcoRI double en-zyme digestion and T4 DNA Ligase connection. The recombinant pCMV-N-Flag-SND1-No1/2 plasmids were transfected in-to HeLa cells and the expression of Flag-SND1-No1/2 fusion proteins was examined by Western blotting assay. Immunofluo-rescence assay was performed to detect the co-localization of Flag-SND1-No1/2 with endogenous SND1 granule. Results The pCMV-N-Flag-SND1-No1/2 were sequenced and digested correctly by restriction single/double enzyme. The Flag-tagged SND1-No1/2 fusion proteins were also detected in transfected HeLa cell by Western blotting assay. Both of them showed the co-localization with endogenous SND1 granule. Conclusion The recombinant eukaryotic plasmids of pCMV-N-Flag-SND1-No1/2 were constructed successfully and expressed effectively. The depletion of 1st AUG failed to af-fect the formation of SND1 containing stress granules.