Biomedical subjects

Wei Yi

Publications and source records attributed to Wei Yi.

22 records · Page 2Linked to original sources

PubMed2002

[Effect of JIP on the proliferation and apoptosis of nasopharyngeal carcinoma cells].

BACKGROUND & OBJECTIVE: Previous studies showed that JNK signaling pathway activated by LMP1 plays an important role in carcinogenesis of nasopharyngeal carcinoma (NPC). JNK interacting protein (JIP) can inhibit JNK signaling pathway in NPC cell. This study was designed to elucidate the effect of JIP on the proliferation and apoptosis of NPC cells. METHODS: After treatment with JIP at different concentrations and time points, the number of proliferating cells were determined by MTT assay; the ability of proliferation of NPC cells was measured by the rate of cloning formation; cell cycle and the apoptotic rate of NPC cells was assayed by flow cytometry. RESULTS: 1. MTT assay showed that cell proliferation was significantly inhibited by JIP in a dose- and time-dependent manner. After treatment with JIP for 24, 48, and 72 hours, the rate of survival cells were 77.8%, 59.2%, and 61.8%, respectively. 2. The number and volume of colonies were decreased after transfection with JIP. 3. The number of cells in S phase was decreased from 25.87% to 19.96%, and the number of cells in G0/G1 phase was elevated from 66.24% to 71.89% after treatment with JIP. 4. In contrast to the control group, the 24 hours apoptotic rate was elevated from 1.25% to 8.25% (about 6.6 times); the 48 hours apoptotic rate was elevated from 1.04% to 31.45% (about 30 times). CONCLUSIONS: The results demonstrated that JIP inhibit the growth of nasopharyngeal carcinoma through arresting the cell cycle at G1/S checkpoint and triggering the apoptosis of cells. Data suggest that JIP is a potent molecular drug for the treatment of the patients with nasopharyngeal carcinoma.

Adaptor Proteins, Signal Transducing↗

PubMed2002

[Effect of electro-acupuncture on calcium content in neurocytes of focal cerebral ischemia].

OBJECTIVE: To study the effect of electro-acupuncture (EA) in regulating calcium (Ca2+) content in brain neurocytes of rats with focal cerebral ischemia. METHODS: The changes of Ca2+ content in ischemic neurocytes were observed by using laser confocal scanning microscope. RESULTS: Ca2+ content did not change significantly in cerebral cortex when the brain ischemia occurred for 1 hr, but it raised significantly in striatum neurocytes. Both the Ca2+ contents in striatum and cortex area increased significantly 3 hrs after ischemia occurrence and the content in striatum was higher than that in cortex significantly. Brain Ca2+ content could be reduced significantly after the 3 hrs ischemic brain were treated by EA for 30 min. CONCLUSION: EA could regulate the content of Ca2+ in the ischemic area of brain, inhibit Ca2+ overload, so as to protect neurons from ischemic injury.

Animals↗

PubMed2000

Induction of Apoptosis in Tumor Cells by a Recombinant Adenovirus with bak Gene.

Apoptosis, a genetically encoded process of cellular suicide, comprises an intrinsic cellular defence against tumorigenesis. bak(for bcl-2 homologous antagonist/killer) is a new apoptosis-inducing gene found recently, which is identified in all tissues examined. Initial work of Farrow, Chittenden and Klefer indicated that bak plays an important role in apoptosis. Successive work of others suggests inactivity of Bak always accompanies the development of tumor cells. In this work, a shuttle vector harboring bak gene, pCA13-bak, was constructed and used to cotransfect into the cell line 293 together with a recombinant plasmid, pBHG11, containing most of adenovirus genome. A mutant adenovirus(delete E1, E3 region)carring bak, Ad-bak, was obtained, and purified. Dot blot identified the construction of recombinant virus was successful. HeLa cells were infected by this virus. Some manners were used to identify the changes of HeLa cells including Annexin V-FITC staining which made the reversed PS observed directly, microscope observation and others. The characteristic morphology of apoptotic cells was due to Ad-bak. The experiment suggests that bak is a strong apoptosis-inducing gene, and a potential gene which could be used in gene therapy on tumor.

Journal Article↗

PubMed2000

The Primary Study on Expression and Function of D-Type Cyclins in Nasopharyngeal Carcinoma Cell Lines.

Previous work of the authors established the protein expression spectra of D-type cyclins, and found that there were differential expression in nasopharyngeal carcinoma (NPC) biopsies. Using Western Blotting, aberrant overexpression of the cyclinD1 protein in NPC cell lines is reported. CyclinD2 and cyclinD3, the other members of D-type cyclins, were also detected in NPC cell lines. A comparison of the expression patterns in the cell lines, positive or negative in the latent membrane protein 1 (LMP1) encoded by Epstein-Barr virus, revealed that the expression of D-Type cyclin proteins might be increased by EBV-LMP1. The abundance of these proteins showed characteristic variation consistent with a cell- cycle-dependent oscillation and the peak levels expressed in G1 as analyzed by double-parameter flow cytometry. These data suggest that cyclinD1 is essential for cell cycle progression in G1 and may play a role in NPC carcinogenesis.

Journal Article↗