CAJ | 학술논문

目的研究异常表达的脑源性神经营养因子(BDNF)在多发性骨髓瘤(MM)发生、发展中的作用及其信号通路.方法采用锥虫蓝拒染法检测BDNF对人MM细胞系RPMI8226、U266和KM3细胞存活的促进作用,MTT比色法观察BDNF对苯丙氨酸氮芥和长春新碱细胞毒作用的影响,Western blot检测BDNF对MM细胞TrkB磷酸化的影响.通过动物模型观察BDNF对肿瘤生长和实验动物存活时间的影响.结果 BDNF以浓度依赖性方式促进MM细胞的存活,50μg/L BDNF作用后存活细胞数较对照组明显增加.BDNF可明显降低苯丙氨酸氮芥和长春新碱的细胞毒性,50μg/LBDNF作用后,苯丙氨酸氮芥和长春新碱的EC50值分别为无BDNF作用时的2倍和3倍.体内实验表明BDNF可明显促进异种移植的MM裸鼠模型中肿瘤的生长,经BDNF处理和未经BDNF处理组肿块的平均体积分别为3240.9 mm3和1032.7 mm3(P＜0.05),生存时间分别为13 d和21 d(P＜0.05).MM细胞中异常表达的TrkB是BDNF的功能性受体,外源性BDNF作用后,MM细胞TrkB磷酸化水平明显增加,并且Trk抑制剂K252a可明显抑制BDNF诱导的MM细胞迁移.结论外源性BDNF可磷酸化激活MM细胞表面TrkB受体,促进骨髓瘤细胞的增殖、存活、迁移并参与骨髓瘤细胞的化疗耐药,在MM的病理生理进程中起重要作用.
목적 연구이상표체적뇌원성신경영양인자(BDNF)재다발성골수류(MM)발생、발전중적작용급기신호통로.방법 채용추충람거염법검측BDNF대인MM세포계RPMI8226、U266화KM3세포존활적촉진작용,MTT비색법관찰BDNF대분병안산담개화장춘신감세포독작용적영향,Western blot검측BDNF대MM세포TrkB린산화적영향.통과동물모형관찰BDNF대종류생장화실험동물존활시간적영향.결과 BDNF이농도의뢰성방식촉진MM세포적존활,50μg/L BDNF작용후존활세포수교대조조명현증가.BDNF가명현강저분병안산담개화장춘신감적세포독성,50μg/LBDNF작용후,분병안산담개화장춘신감적EC50치분별위무BDNF작용시적2배화3배.체내실험표명BDNF가명현촉진이충이식적MM라서모형중종류적생장,경BDNF처리화미경BDNF처리조종괴적평균체적분별위3240.9 mm3화1032.7 mm3(P＜0.05),생존시간분별위13 d화21 d(P＜0.05).MM세포중이상표체적TrkB시BDNF적공능성수체,외원성BDNF작용후,MM세포TrkB린산화수평명현증가,병차Trk억제제K252a가명현억제BDNF유도적MM세포천이.결론 외원성BDNF가린산화격활MM세포표면TrkB수체,촉진골수류세포적증식、존활、천이병삼여골수류세포적화료내약,재MM적병리생리진정중기중요작용.
Objective To explore the significance of abnormal expression of brain-derived neurotrophic factor(BDNF)/TrkB in the development and evolution of multiple myeloma(MM)and the involved signaling pathwavs.Methods The effect of BDNF on the cell viability of human myeloma cell line(HMCL)(RPMI8226,U266,KM3)was determined by trypan blue dye-exclusion.MTF assay was used to evaluate the cytotoxicity of tested chemotherapeutic agents.The effect of BDNF on the phosphorylation of TrkB was determined bv Western blot.A human myeloma xenograft animal model was used to evaluate the effects of BDNF on tumor growth and survival time.Resets BDNF at 50μg/L triggered significant increase in cell viability of HMCL.BDNF protected KM3 cells from melphalan and vincristine.The viability of KM3 cells exposed to varying concentrations of melphalan with and without 50μg/L BDNF showed that BDNF induced almost a 2-fold and a 3-fold increase in melphalan and vincristine toxicity respectively.BDNF treatment increased MM cell growth in xenografted MM model(3240.9 mm3 vs 1032.7 mm3)(P＜0.05).Intratumoral injection of BDNF also significantly reduced survival time(13 d vs 21 d)(P＜0.05).The phosphorylated TrkB level was increased significantly after treated by exogenous BDNF.BDNF-triggered migration in RPMI8226 cells was completely abrogated by a Trk tyrosine kinase inhibitor K252a. Conclusion BDNF can activate TrkB signaling cascades resulting in MM cells growth,migration,and chemoprotection and appears to haVe a major contribution to the pathogenesis of MM.