Inhibitory effect of triptolide on lymph node metastasis in patients with non-Hodgkin lymphoma by regulating SDF-1/CXCR4 axis in vitro.
OBJECTIVE
To investigate the antiproliferative effect of triptolide on B-NHL cell line Raji cells, to study its effect on lymph node metastasis in patients with non-Hodgkin's lymphoma (NHL) in vitro, and to explore the underlying mechanism regulating SDF-1/CXCR4 axis.


METHODS
The effects of triptolide on the growth of Raji cells were studied by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium (MTT) assay. The effects of triptolide on SDF-1 mRNA expression in lymph node stromal cells from patients with NHL were determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The effects of triptolide on CXCR4 expression on lymphoma cells freshly isolated from the lymph nodes of these patients were studied by flow cytometric analysis. Chemotaxis assays were performed to observe the effects of triptolide on migration of primary lymphoma cells towards recombinant human SDF-1 alpha (rhSDF-1 alpha) or cultured lymph node stromal cells in vitro.


RESULTS
Triptolide inhibited the proliferation of B-NHL cell line Raji cells in a dose- and time-dependent manner with a 24-h IC50 value of 43.06 nmol/L and a 36-h IC50 value of 25.08 nmol/L. The expression of SDF-1alpha mRNA in lymph node stromal cells obtained from patients with NHL was decreased after treatment by triptolide at concentrations of 25 and 50 nmol/L for 24 h. Flow cytometry analysis showed that the CXCR4 expression on primary lymphoma cells were downregulated gradually in a dose-dependent manner following triptolide treatment. Chemotaxis assays revealed that the migration of freshly isolated lymphoma cells towards either rhSDF-1 or cultured lymph node stromal cells was markedly inhibited by the addition of triptolide in vitro, and the inhibition was dose-dependent.


CONCLUSIONS
Triptolide can inhibit the proliferation of B-NHL cell line Raji cells. Moreover, triptolide is able to inhibit the migration of lymphoma cells via lymph nodes in vitro. The potential antitumor mechanisms of triptolide are related to the antiproliferative effect and the blockage of SDF-1/CXCR4 axis.
Zhang
Chun
C
Department of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. zhangchun23@yahoo.com.cn
Cui
Guo-hui
GH
Liu
Fang
F
Wu
Qiu-ling
QL
Chen
Yan
Y
D018906:Antineoplastic Agents, Alkylating / Q000008:administration & dosage / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D054377:Chemokine CXCL12 / Q000096:biosynthesis* / Q000235:genetics; D002633:Chemotaxis / Q000187:drug effects; D004224:Diterpenes / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004852:Epoxy Compounds / Q000008:administration & dosage / Q000494:pharmacology; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D016393:Lymphoma, B-Cell / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000378:metabolism* / Q000473:pathology; D010616:Phenanthrenes / Q000008:administration & dosage / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D019718:Receptors, CXCR4 / Q000378:metabolism*; D017154:Stromal Cells / Q000378:metabolism; D029757:Tripterygium / Q000737:chemistry
D018906:Antineoplastic Agents, Alkylating; D054377:Chemokine CXCL12; C486264:Cxcr4 protein, rat; D004224:Diterpenes; D004852:Epoxy Compounds; D010616:Phenanthrenes; D012333:RNA, Messenger; D019718:Receptors, CXCR4; C001899:triptolide