食管癌对神经生长及导向作用的研究

Effects of esophageal cancer on the nerve fiber growth and guidance

目的建立肿瘤与神经共培养模型，探讨食管癌对神经生长和导向的作用。方法采用原代分离培养的方法，取大鼠的背根神经节，将背根节与转染绿色荧光蛋白的食管癌EC109细胞共培养，观察肿瘤细胞对神经生长的影响，并计算神经轴突的数目与面积。采用实时定量PCR检测食管癌细胞系EC109和EC9706中神经生长因子（NGF）和脑源性神经生长因子（BDNF）的表达情况。结果食管癌细胞与背根节细胞混合普通培养，背根节细胞发出轴突靶向肿瘤细胞生长。食管癌细胞与背根节组织共培养后，近肿瘤细胞侧背根节长出的轴突较长、较浓密，远肿瘤侧则较短、较稀疏。共培养第7天，近肿瘤侧神经突的数目与面积分别为87个和346μm^2，远肿瘤侧分别为23个和141μm^2，差异均有统计学意义（P〈0．05）。PCR检测发现，NGF和BDNF均表达于食管癌细胞。结论食管癌细胞对神经纤维有促生长和导向作用，该作用的发挥可能与NGF和BDNF等神经营养因子的分泌有关。

Objective To establish the co-culture model of cancer cells and nerve, and to study the influence of esophageal cancer on nerve fibers. Methods Mouse dorsal root ganglion （DRG） was cultured in sterile conditions by primary isolation. Co-culture model was established using matrigel matrix-embedded DRG and EC109 （esophageal cancer cell line） transfected with green fluorescent protein. Morphological changes of DRG, number and area of neurites were quantified with microscopy and image analysis. Furthermore, the mRNA expression of nerve growth factor（NGF） and brain derived neurotrophie factor （BDNF） was detected by real-time PCR. Results In mixture cultivation model of ECI09 and DRG cells, directional outgrowth of neurite projecting to EC109 was observed, and the length of neurite was markedly longer in proximal field compared to distal field. The number and area of neurite were 87 and 346 p,m2 in proximal field respectively, and 23 and 141 p,m2 in distal field on the 7th day. The expressions of NGF and BDNF were up-regulated in esophageal cancer cells. Conclusions The esophageal cancer may play an important role in nerve fiber growth and guidance, which may be associated with the up-regulation of NGF and BDNF expressions.