OBJECTIVETo evaluate the mechanism and influence of thalidomide on interleukin-6 (IL-6), IL-6 receptor (IL-6R) and its transmitting chain in multiple myeloma patients.

METHODSSerum level of IL-6, expression of IL-6R on myeloma cells and IL-6R beta mRNA in multiple myeloma patients were measured by enzyme linked immunosorbent assay (Elisa), flow cytometry and reverse transcription polymerase chain reaction (RT-PCR).

RESULTSSerum level of IL-6 in multiple myeloma patients was 564.8 +/- 319.4 ng/L, with a positive rate on the myeloma cells of 33.6% before oral 200 mg/d thalidomide. They were 560.3 +/- 414.8 ng/L and 31.8% on D14 after oral 200 mg/d thalidomide, which were not significantly different as compared with those before (P > 0.05). On D14, 28, 42, 56 and 84 after oral 400 mg/d thalidomide, the serum level of IL-6 in multiple myeloma patients were 516.7 +/- 131.9 ng/L, 426.7 +/- 180.4 ng/L, 387.9 +/- 187.4 ng/L, 350.1 +/- 85.5 ng/L and 212.3 +/- 92.5 mg/L, with positive rates on the myeloma cells of 28.5%, 24.3%, 21.3%, 12.6% and 10.1%, which were all lower than those before oral 200 mg/d thalidomide (P < 0.05 or P < 0.01). Ratios before and on D14 after oral 200 mg/d thalidomide were 7.8 and 6.9, with no statistical significance (P > 0.05). Ratios on D14, 28 after oral 400 mg/d thalidomide were 5.3 and 2.7, which were lower than those before oral 200 mg/d thalidomide (P < 0.01).

CONCLUSIONReduction of serum level of IL-6 in multiple myeloma patients and decrease in IL-6R expression on the myeloma cells and IL-6R beta mRNA occur on D14 after oral 400 mg/d thalidomide. These changes become more obvious with time. The antitumor mechanism of thalidomide may be related to reduction of IL-6 serum level in multiple myeloma patients and decrease in IL-6R expression on the myeloma cells and IL-6R beta mRNA.

Aged ; Angiogenesis Inhibitors ; pharmacokinetics ; pharmacology ; Female ; Humans ; Interleukin-6 ; blood ; genetics ; Male ; Middle Aged ; Multiple Myeloma ; blood ; metabolism ; RNA, Messenger ; drug effects ; metabolism ; Receptors, Interleukin-6 ; metabolism ; Thalidomide ; pharmacokinetics ; pharmacology

The purpose of this study was to determine whether rapamycin could inhibit corneal angiogenesis induced by basic fibroblast growth factor (bFGF). Using human dermal microvascular endothelial cells (HDMECs), we examined the effect of rapamycin on cell proliferation and migration, and the expression of vascular endothelial growth factor (VEGF). The rabbit's eye was implanted intrastromally into the superior cornea with pellet containing bFGF for the control group and pellet containing bFGF and rapamycin for the rapamycin group. Biomicrographically, corneal angiogenesis was evaluated for 10 days after pellet implantation. The neovascularized cornea also was examined histologically. bFGF induced corneal neovascularization was significantly reduced by treatment with rapamycin. Using in vitro model, rapamycin strongly inhibited bFGF induced proliferation, migration, and VEGF secretion of HDMECs. We could observe that the bFGF induced corneal angiogenesis was inhibited by rapamycin in a micropocket rabbit model. The score of neovascularization was significantly decreased in the rapamycin group than in the control group at 10 days after pellet implantation. Histologically, the cornea of rapamycin group also showed much less new vessels than that of control group. Collectively, rapamycin appears to inhibit bFGF induced angiogenesis in a rabbit corneal micropocket assay and may have therapeutic potential as an antiangiogenic agent.
Vascular Endothelial Growth Factor A/biosynthesis ; Sirolimus/pharmacokinetics/*pharmacology ; Rabbits ; Humans ; Fibroblast Growth Factor 2/pharmacokinetics/pharmacology ; Female ; Endothelial Cells/cytology/drug effects/metabolism ; Drug Implants ; Dose-Response Relationship, Drug ; Corneal Neovascularization/*drug therapy/pathology ; Cells, Cultured ; Cell Proliferation/drug effects ; Cell Movement/drug effects ; Animals ; Angiogenesis Inhibitors/pharmacokinetics/*pharmacology