[Regulatory effect of thalidomide on the expression of costimulatory molecules in patients with multiple myeloma].
OBJECTIVE
To investigate the expression of B7 co-stimulatory molecules in human multiple myeloma (MM) and the immunoregulatory effects of thalidomide on B7.1 co-stimulator.


METHODS
The immunoregulatory effects of thalidomide on the expression of B7-1 in human MM cell line was examined by detecting the changes in the expression of B7 co-stimulator on the cells using flow cytometry following the drug treatment.


RESULTS
The expression of B7.1 co-stimulator was lowly expressed in human MM cell line and MM patients, with a positivity rate of 0.8 and (2.19-/+2.13) for B7.1 and a rate of 26.4 and (30.28-/+28.11) for B7.2, respectively. Compared with the control group, the thalidomide-treated cells showed significantly increased percentage of CD-80 positive cells in a dose-dependent manner (but not at 0.1 microg/ml) (P<0.01), with the highest percentage reaching (17.7-/+1.53)% at thalidomide concentration of 5 microg/ml.


CONCLUSIONS
MM cells express low or undetectable levels of B7.1. Thalidomide can up-regulate the expression of B7-1 molecules on myeloma cells, which is probably one of the therapeutic mechanisms of thalidomide.
Yang
Yun
Y
Department of Hematology, Second Affiliated Hospital of Xi'an Jiaotong University College of Medcine, Xi'an, China. yangyun108@21cn.com
Zhang
Wang-gang
WG
He
Ai-li
AL
Yang
Hui-yun
HY
Wang
Ying
Y
Tian
Wei
W
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018122:B7-1 Antigen / Q000187:drug effects* / Q000378:metabolism; D045744:Cell Line, Tumor; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology; D013792:Thalidomide / Q000627:therapeutic use*; D015854:Up-Regulation / Q000187:drug effects
D018122:B7-1 Antigen; D013792:Thalidomide