Differential proteomics analysis on hydroquinone-induced cytotoxicity in TK6 cells / 中国职业医学

OBJECTIVE: To study the effect of hydroquinone on the protein expression on human lymphoblastoid cell TK6,and to explore the molecular mechanism of hydroquinone-induced cellular response. METHODS: The TK6 cells were treated with 20. 0 μmol/L of hydroquinone for 24. 0 hours. Total protein was extracted by protein lysis buffer and quantified. The proteins were separated by two-dimensional gel electroporthressis. After image analysis,the difference in electrophoresis was selected for enzymatic hydrolysis. The mass spectrometry identification was performed using matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometry. The TK6 cells were treated with hydroquinone at a concentration of 0. 0,5. 0,10. 0 and 20. 0 μmol/L for 24. 0 hours,and total protein was extracted. The expression of heat shock protein 70( HSP70) and ubiquitin-binding enzyme 2( UBE2N) of which were identified by mass spectrometry were assayed by western blot. RESULTS: A total of 48 differential expression protein spots were detected after hydroquinone treatment,and the mass spectrometry identified 30 differentially expressed proteins with up-or down-regulation. These proteins were related to oxidative stress,mitochondrial energy metabolism,cytoskeleton,cell cycle,DNA damage repair,and so on. The relative expression levels of HSP70 and UBE2 N in TK6 cells of 5. 0,10. 0,20. 0 μmol/L hydroquinone group were higher than those of 0. 0 μmol/L hydroquinone group( P < 0. 05),which was consistent with the mass spectrometry results. CONCLUSION: Hydroquinone can induce cytotoxicity in TK6 cells through oxidative stress,which induces the change of mitochondrial energy metabolism and DNA damage repair.

Micronuclei and Gene Mutation at tk Locus Induced by Cyclophosphamide in TK6 Human Lymphoblastoid Cells / 环境与健康杂志

Objective To establish a method to investigate micronuclei (MN) and gene mutation at the heterozygous thymidine kinase (tk) locus induced by environmental mutagens in TK6 human lymphoblastiod cells. Methods TK6 cells were used to detect cytotoxic response, MN and mutation frequency at tk locus induced by cyclophosphomide (CP) after treatment with S9 mixture for 4 h. Results Exposure to CP for 4 h decreased relative survival (RS), induced both MN and TK mutation in a concetration-dependent manner. The maximum induction of MN and TK mutations were 8.8 and 15.7 times compared with those of control. Two distinct phenotypic colonies of TK mutants were generated, namely tk-NG and tk-SG mutant colonies but mainly the latter. Conclusion CP induced both MN and TK mutation in TK6 cells. TK6 cells can be used as an in vitro assay system to assess cytogenetic damage and gene mutation at tk locus of environmental chemicals.

EFFECT OF CURCUMIN ON PROLIFERATION AND APOPTOSIS OF TK6 CELLS / 营养学报

Objective: To explore the effect of curcumin on proliferation and apoptosis of TK6 human diploid lymphoblastoid cells.Methods: MTT colorometric assay, 3H-TdR incorporation, cell cycle analysis were used to evaluate the effect on proliferation, and morphology microstructure. Flow cytometry was used to detect the effect on apoptosis induction on TK6 cell.Results: Curcumin could inhibit proliferation by blocking transition from G0/G1 to S phase, induce apoptosis in TK6 cells. The effective dose for proliferation inhibition and apoptosis induction is 20 ?mol/L.Conclusion: Apoptosis induction is one of important mechanisms for anti-mutagenic, anti-tumor action of curcumin.