Objective: To investigate the effects of recombinant human bone morphogenetic protein (rhBMP-2) on the biological characteristics of human glioma cells (SHG44) in vivo and in vitro.
Methods: The growth curve of SHG44 cells was ploted with or without rhBMP-2. The proliferation quantity of SHG44 cells with rhBMP-2 was determined by MTT method. The cell cycle, ultrastructure and DNA fragments of SHG44 cells were detected respectively by flow cytometry (FCM), electron microscope and agarose gel electrophoresis. Tumor growth state of SHG44 gliomas, which grew under the skin of nude mice, was observed with local injection of rhBMP-2.
Results: FCM showed that rhBMP-2 inhibited the growth of SHG44 cell in vitro and its effect depended on dosage. DNA content of SHG44 cells in G1 phase was obviously increased (5 mg/L group, 77.4%; control group, 55.2%, P < 0.05) and the content of its S phase was reduced (5 mg/L group, 15.2%; control group, 33.3%, P < 0.01). The apoptosis spike (12.3%) occurred in the 5 mg/L group. The nucleolus chromatin condensation, bound of aggregation and caryorrhexis were observed under the electron microscope and the apoptotic cells appeared. DNA electrophoresis showed a ladder strap (DNA ladder). SHG44 glioma growth was relatively slower and its volume was smaller with the biquadratic local injection of rhBMP-2 (tumor end volume in average: experimental group 894 mm(3) +/- 145 mm(3), control group 5 163 mm(3) +/- 1 028 mm(3), P < 0.01
Conclusion: rhBMP-2 can suppress the proliferation of SHG44 gliomas and induce its apoptosisN: