[Adenovirus mediated antisense c-myc gene on the chemotherapy sensitivity of osteosarcoma cells to cisplatin].
OBJECTIVE
To construct the recombinant adenovirus encoding antisense c-myc fragment and to investigate its effect on the chemotherapy sensitivity of osteosarcoma MG-63 cells to cisplatin.


METHODS
The recombinant adenovirus (Ad-Asc-myc) encoding antisense c-myc fragment was constructed by cloning c-myc cDNA of about 720 base pairs in a reverse direction into adenovirus vector, then undergoing recombination, amplifying and being complemented in vivo. The osteosarcoma MG-63 cells were transfected by the Ad-Asc-myc in vitro, and Wright staining, Acridine Orange staining, Western Blot, MTT, Flow Cytometry (FCM) were used to study cell morphology, expression of c-myc protein, tumor cell proliferation in vitro, apoptosis and cell cycle change.


RESULTS
Ad-Asc-myc encoding antisense c-myc fragment was obtained with the titer of 2 x 10(9) pfu/ml. Ad-Asc-myc down-regulated the expression of c-myc protein after transfected MG-63 cells for 48 h, combined with the treatment of 2.0, 5.0 microg/ml cisplatin for 2 h could inhibit tumor cells proliferation in vitro by 33.4% and 54.2% respectively, which were significantly difference compared with control recombinant adenovirus (Ad-LacZ) groups (P < 0.05). Acridine Orange staining and FCM analysis showed that Ad-Asc-myc could induce apoptosis of transfected cells, which was enhanced by the treatment of cisplatin cell. Cycle analysis showed that obvious G2/M phase arrested in transfected cells.


CONCLUSIONS
Ad-Asc-myc increases the chemotherapy sensitivity of osteosarcoma MG-63 cells to cisplatin as well as induced apoptosis.
Yang
Di-sheng
DS
Department of Orthopaedics, The Second Hospital Affiliated Zhejiang University College of Medicine, Hangzhou 310009, China. xiexk2@163.com
Xie
Xian-kuan
XK
Ye
Zhao-ming
ZM
Tao
Hui-min
HM
D000260:Adenoviruses, Human / Q000235:genetics*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D002945:Cisplatin / Q000494:pharmacology*; D016373:DNA, Antisense / Q000235:genetics*; D016259:Genes, myc; D005822:Genetic Vectors; D006801:Humans; D012516:Osteosarcoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D011995:Recombination, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D016373:DNA, Antisense; D016271:Proto-Oncogene Proteins c-myc; D002945:Cisplatin