Abstract:

To investigate the effect and molecular mechanisms of FHIT expression on apoptosis of human gastric cancer cells (MGC803) induced by docetaxel (DOC). MethodsRecombination eukaryotic expressive plasmids with exogenous FHIT were transfected into MGC803 by liposomes. The cell line which acquired a stable expression of recombinant plasmid pRcCMVFHIT was successfully built by the Central Laboratory of the Provincial Hospital Affiliated to Shandong University. Exogenous FHIT protein expression was assayed  by Western Blot. At different concentrations（1.0, 5.0, 10, 20, and 40?μg/mL） and different times (24, 48, and 72?h), Methyl thiazolyl tetrazolium (MTT) assay was used to determine the inhibitory ratio of gastric cancer cell MGC803 treated by docetaxel to choose the best concentration and time. Flow cytometry was employed to detect the apoptotic ratio of gastric cancer cells treated by FHIT and DOC. Proteinum expression of cleavedCaspase3 was determined by Western Blot. ResultsThe cell line which acquired a stable expression of recombinant plasmid pRcCMVFHIT was successfully build. DOC had an inhibitory effect, which was most obviously at 20?μg/ml and 48?h, to gastric cancer cells. The apoptotic ratio in the DOC in combination with pRcCMVFHIT group (65.54%) was significantly higher than that in the control(3.27%), pRcCMV (3.55%), pRcCMVFHIT (13.94%), DOC (44.13%), and DOC + pRcCMV groups (45.29%)(P＜0.05). CleavedCaspase3 proteinum expression in the DOC+pRcCMVFHIT group was significantly higher than in any other groups. ConclusionFHIT expression in combination with DOC synergistically promotes the apoptosis of gastric cancer cells, which maybea result of the upregulation of Caspase3 proteinum expression induced by them.

Key words: Stomach neoplasms； Fragile histidine triad； Gene expression； Docetaxel； Apoptosis