Study On Interaction Between Esophageal Cancer And Nerve In Morphology And Significance Of Perineural Invasion In Patients With Esophageal Cancer

【Background】The development of tumor is closely related to microenvironment of tumor cells. In1971, Folkman showed for the first time the evidence for the ability of tumor to foster newblood vessels, a process called neoangiogenesis, and proposed that the growth of tumorrelied on neoangiogenesis. From then on, a series of studies have been invested to uncoverthe relationship between tumor and vascular and find treatment of tumor by blocking itsblood supply. Lymphatic metastasis is the main style for spread of tumor. Some studieshave shown that expression of VEGF-C and VEGF-D is associated withlymphangiogenesis in several human tumor. The nerve often accompanied with bloodand lymphatic vessels. Similar to the processes of neoformation of blood and lymphatic vessels, some evidence point out the possibility of neoneurogenesis. Psychological factorswas closely related to tumor development. The incidence of tumor in people who havedepression and stress is higher than the general population. Although some evidence havedescribed the presence of nerve in tumors, the relationship between tumor and nerve isstill not clear.【Objective】1. To establish the3-dimensional co-cultivatable model of cancer cells and nerve.2. To study the interaction of tumor and nerve in morphology in vivo, and provide thebasic evidence to uncover the mutual effect between tumor and nerve.3. To compare the two detection methods in determining perineural invasion, and toanalysis the relationship between perineural invasion and clinicopathology in patients withesophageal squamous cell carcinoma.【Methods】1. Mouse dorsal root ganglion (DRG) was cultivatabled in sterile conditions byprimary isolation. Co-cultivatable model of3-dimensional was established using matrigelmatrix-embedded DRG and EC109transfected with GFP.2. Observe the interaction between tumor cells and nerve by3-D co-cultivatablemodel and normal co-cultivatable. Numbers of neurites and neurite area were quantitatedwith microscopy and image analysis. Observe the morphological changes of tumor cellsand perineural invasion in3-D co-cultivatable model. Furthermore, the mRNA expressionof NGF and BDNF in esophageal cancer cells were detected by real time PCR.3. The level of perineural invasion was evaluated in126patients with esophagealsquamous cell carcinoma by hematoxylin-eosin staining and immunohistochemistry withneuro-specific antibody S100respectively. Analysis the relationship between perineuralinvasion and clinicopathology in patients with esophageal squamous cell carcinoma【Results】1. We successfully establish the3-dimensional co-cultivatable model betweenesophageal cancer cells and mouse dorsal root ganglion which provived a good research platform for further experiments.2. In mixture cultivatable model of EC109and DRG cells, directional outgrowth ofneuritis projecting to EC109was observed. In3-D co-cultivation of cancer cells and DRG,the lengths of neuritis were markedly longer in proximal field compared to distal field. Onthe4th day, the numbers of neuritis were28and7respectively in proximal field comparedwith distal field, and neurite area were109μm2and42μm2in proximal field comparedwith distal field. The numbers of neuritis and neurite area were87and346μm2inproximal field respectively, and23and141μm2in distal field on the7th day. Theexpression of NGF and BDNF were expressed in esophageal cancer cells. It is found thatthe tumor cells could metastasis through nerve in3D co-cultivatable model.3. Immunohistology with S100staining, which were clear and intuitive, were moreuseful to determine the perineural invasion than HE staining. The level of perineuralinvasion in126patients with esophageal cancer evaluated by HE staining was28.57%while the level was51.59%determined by immunohistology with S100staining. Thesetwo methods were significantly different in evaluating perineural invasion by McNemartest. Perineural invasion was associated with a larger tumor size (P=0.001), AJCC stage(P<0.001), T stage (P<0.01) and vascular invasion.【Conclusions】This study demonstrates that there are reciprocal effect between esophageal cancerand nerve. The esophageal cancer have positive roles on the nerve fiber growth andguidance; the nerve can influence the biological behavior of esophageal cancer, such asproliferation and metastasis. The esophageal cancer cells can migrate through the nerve, aprocess called perineural invasion. Immunohistology staining with S100improve theaccuracy of evaluating perineural invasion. Perineural invasion in esophageal cancer mayhave an important role in esophageal cancer.