[Retinoic acid enhances chemosensitivity of medulloblastoma cells in vitro and its potential mechanism].
OBJECTIVE
To elucidate the chemosensitivity of retinoic acid (RA)-differentiated medulloblastoma Med-3 cells to conventional anti-cancer drug and to determine the potential genetic factor(s) mediating this sensitivity.


METHODS
Ten mumol/L RA, 5 micrograms/ml cisplatin (DDP) and their combination with one half concentration of each were used respectively to treat human medulloblastoma cell line Med-3 in vitro. Cell proliferation, morphology and death pattern as well as Fas/FasL expressions were analyzed by multiple approaches.


RESULTS
Both soluble and membrane FasL could be detected in the treated and untreated Med-3. Fas was positive in the cytoplasm of Med-3 cells and the cells could produce soluble Fas. DDP had no obvious effect on Fas expression. RA up-regulated Fas expression and translocalization from cytoplasm to cell membrane of the treated cells. Neither RA nor DDP could trigger apoptosis but in combination could effectively induce apoptosis.


CONCLUSIONS
RA could enhance the apoptotic susceptibility of Med-3 cells to DDP presumably through modulating the Fas expression pattern. Combined RA/DDP regimen would have potential clinical value in the management of medulloblastomas.
Liu
J
J
Division of Molecular Biology, Shenyang Medical College, Shenyang 110031, China.
Guo
L
L
Liu
N
N
D000970:Antineoplastic Agents / Q000494:pharmacology*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D017209:Apoptosis; D002528:Cerebellar Neoplasms / Q000188:drug therapy; D002945:Cisplatin / Q000494:pharmacology; D004357:Drug Synergism; D053222:Fas Ligand Protein; D006801:Humans; D008527:Medulloblastoma / Q000188:drug therapy; D008562:Membrane Glycoproteins / Q000378:metabolism; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects; D019014:fas Receptor / Q000096:biosynthesis
D000970:Antineoplastic Agents; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D019014:fas Receptor; D014212:Tretinoin; D002945:Cisplatin