中文摘要：

背景与目的：失巢凋亡抑制因子酪氨酸激酶受体B（tyrosine kinase receptor，TrkB）能诱导正常上皮细胞的恶性转化并且使该细胞具有高侵袭能力。TrkB过度表达与神经母细胞瘤和其他多种人类高侵袭性恶性肿瘤的化疗耐药和不良预后有关。本研究旨在探讨TrkB及其配体脑源性神经营养因子（brain-derived neurotrophic factot，BDNF）在卯巢上皮性癌细胞系OVCAR-3中的表达及其意义。方法：检测卵巢癌细胞系OVCAR-3细胞贴壁培养（AC）、细胞立体培养（ATC）以及细胞立体培养得到的多细胞团簇（CS）经胰酶消化成单细胞后再次贴壁培养（RAC）细胞中TrkB及BDNF的表达差异。结果：经RT—PCR检测，与贴壁培养细胞（adhesive cells）比较，TrkB mRNA高表达于OVCAR-3多细胞团簇中（multicellular—spheroids），两组数值分别（23．5±0．5）％，（35．3±0．7）％，差异有显著性（P〈0．001）；BDNF mRNA的表达则正相反，两组数值分别（41．4±0．6）％，（32．2±0．7）％，差异有显著性（P〈0．001）。经Western blot检测，TrkB的前体蛋白（未发生糖基化的受体形式）广泛地高表达于上述3种不同培养方式的OVCAR-3细胞中；与贴壁培养细胞比较，OVCAR-3细胞立体培养全长TrkB（发生糖基化的完整受体形式，分子量145000）明显高表达（P〈0．001）。结论：卵巢癌细胞中存在TrkB及BDNF的自分泌环路，TrkB可能是介导卵巢痛失巢凋亡抑制的因子。

英文摘要：

Background and purpose： TrkB, a neurotrophic tyrosine kinase receptor, serves as a potent and specific suppressor of anoikis of non-malignant epithelial cells, and induces high invasion capacity in these cells. TrkB over- expression has been associated with chemotherapy resistance and poor survival in neuroblastoma and some other highly aggressive cancers. However, the relationship of the expression of TrkB to anoikis resistance in ovarian cancer cells has rarely been reported in literature. This study investigated the expression and significance of anoikis-suppressor TrkB in OVCAR-3 ovarian cancer ceils. Methods： The expression of TrkB and its ligand BDNF was evaluated in OVCAR-3 ovarian cancer cells under different culture conditions by RT-PCR and Western blot. Results： TrkB mRNA was overexpressed in multicellular spheroids （cell-spheroids,anchorage- independent culture, AIC） as compared to that in OVCAR-3 cells （adhesive-cells, adhesive culture, ACL （35.3±0.7）% versus （23.5±0.5）%; but BDNF mRNA expression was the opposite to the above situation, （41.4±0.6）% versus （32.2±0.7）% （P〈0.001）. Full- length TrkB （glycosylated receptor, 145 000） was overexpressed in OVCAR-3 cell-spheroids compared with OVCAR-3 adhesive-cells （P〈0.001）, and full-length TrkB protein precursor （non-glycosylated receptor） was highly overexpressed in OVCAR-3 ovarian cancer cells under different culture conditions without statistical difference by Western blotting. Conclusions： There was a TrkB and BDNF autocrine-loop in OVCAR-3 ovarian cancer cells. TrkB may acts as an anoikis-suppressor in human ovarian cancer.