Enhanced expression of human vimentin intermediate filaments in hepatocellular carcinoma cells decreases their proliferative and invasive abilities in vitro / 中华肿瘤杂志

<p><b>OBJECTIVE</b>Expression of vimentin in carcinoma cells is a marker for poor prognosis in patients. The aim of this investigation was to assess the influence of vimentin on the characteristics of carcinoma cells.</p><p><b>METHODS</b>The full-length vimentin gene open reading frame (1401 base pairs) was cloned into the plasmid vector pcDNA 3.1 (+), and these vectors were used to stably transfect the human hepatocellular carcinoma HepG2 cell line. Vimentin gene expression was evaluated by RT-PCR and Western blot. Proliferative activity and invasive potential of tumor cells were determined by the CellTiter 96 aqueous one solution cell proliferation assay and BioCoat GFR Matrigel invasion chamber, respectively.</p><p><b>RESULTS</b>DNA sequencing and restriction endonuclease digestion analysis demonstrated that the recombinant vector was correctly cloned. The stable cell line demonstrated a higher vimentin RNA and protein expression. However, both proliferative and invasive abilities of the cells were reduced in vitro ( P < 0.05).</p><p><b>CONCLUSION</b>A recombinant plasmid pcDNA3. 1-VIM is successfully constructed and a carcinoma cell line HepG2-pV highly expressing vimentin is obtained. Recombinant vimentin protein suppresses the proliferative and invasive abilities of HepG2 cells, suggesting that it might decrease malignant phenotype of tumor cells in vitro. This work makes a foundation for further study on the relationship between vimentin and biological phenotype of carcinoma cells.</p>

Searching for genes interacting with human PCIA1 gene by using the bacterial two-hybrid system / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To search for the genes which could interact with newly found homo sapiens cross-immune reaction antigen (PCIA1) gene and accordingly to provide insights into the study of the gene function.</p><p><b>METHODS</b>The Stratagene's BacterioMatch Two-Hybrid System and BacterioMatch Fetal Kidney Library were adopted and the recombinant bait plasmid pBT-PCIA1 was cotransformated with the target plasmid pTRG-cDNA library DNA into the reporter stain. After screening and isolation of positive pTRG clones, the target genes were identified by DNA sequencing and bioinformation analysis.</p><p><b>RESULTS</b>Among all the seven detected target genes, three genes' function were not known, the other four genes had important functions. Their mutations or abberant expression resulted in severe diseases and overexpression of ACTN4 (actinin, alpha 4), PSAP (prosaposin) or EIF3S10 (eukaryotic translation initiation factor 3, subunit 10 theta) could promote tumor development and progression.</p><p><b>CONCLUSION</b>The bacterial two-hybrid system technique is an efficient method, which can provides insights into the study of novel genes' function by detecting protein-protein interactions. This study indicates that PCIA1 gene expression correlates with tumor formation, invasion and metastasis.</p>