Abstract：OBJECTIVE: To investigate whether neuroblastoma cells LA-N-6 express Foxp3 and whether the expression of Foxp3 is sensitive to chemotherapy by cyclophosvnamide（CTX）and pirarubicin（THP）. METHODS: Expression of Foxp3 on LA-N-6 cells was examined by flow cytometry analysis. The dose-effects of chemotherapy drugs including CTX and THP on LA-N-6 cells were investigated by MTT assay. The effects of CTX and THP on Foxp3 expression were examined by flow cytometry and real-time PCR assays. RESULTS: Flow cytometry analysis showed that LA-N-6 cells expressed Foxp3 at a high level. At sub-optimal concentration, chemotherapy drugs CTX and THP significantly down-regulated expression of Foxp3 on LA-N-6 cells at protein level (P<0.05). CTX also decreased the expression of Foxp3 at mRNA level (P<0.05). CONCLSUSIONS: Neuroblastoma cells LA-N-6 express Foxp3 at a high level, which can be suppressed by chemotherapy drugs CTX and THP. These data suggest that chemotherapy might suppress the growth and metastasis of tumor cells partially through inhibiting the expression of Foxp3.［Chin J Contemp Pediatr, 2010, 12 (5):386-389］
SUN Jing,LI Liang,XIAO Yan et al. Neuroblastoma LA-N-6 cells express Foxp3 which can be suppressed by chemotherapeutic agents[J]. CJCP, 2010, 12(05): 386-389.
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