肿瘤内神经新生在口腔鳞状细胞癌进展中的作用及机制

Role of neurogenesis in progress of oral squamous cell carcinoma and its related mechanism

关键词:  神经新生  口腔鳞状细胞癌  细胞迁移  细胞侵袭  ERK/p38/JNK信号通路

Key words:  neurogenesis  oral squamous cell carcinoma  cell migration  cell invasion  ERK/p38/JNK signaling pathway

摘要:

目的 探讨肿瘤内神经新生在口腔鳞状细胞癌（oral squamous cell carcinoma, OSCC）进展中的作用及其机制。方法 利用免疫组化方法在167例人OSCC组织检测泛神经标记物蛋白基因产物（PGP）9.5表达；采用Transwell小室实验检测神经递质降钙素基因相关肽（CGRP）对人舌鳞癌细胞株TSCCA细胞迁移和侵袭的影响；利用免疫印迹方法观察CGRP对TSCCA细胞中细胞外调节蛋白激酶（ERK）、p38、c-Jun氨基末端激酶（JNK）磷酸化的影响；进而观察ERK/p38/JNK抑制剂对CGRP诱导TSCCA细胞迁移和侵袭的影响。结果 88%的OSCC组织中表达PGP9.5，主要分布在肿瘤间质中；PGP9.5中/强阳性表达与肿瘤的分级（r=0.425，P<0.001）、神经浸润（r=0.166，P<0.05）及患者短生存期（r=0.186，P<0.05）呈正相关。CGRP引起TSCCA细胞的迁移数目增加（CGRP： 165.4±14.2，对照： 110.2±5.3，P<0.001），侵袭数目也增加（CGRP： 68.3±23.5，对照： 12.8±2.8，P<0.001）；CGRP处理TSCCA细胞后，1h引起p-ERK的表达上调（P<0.001），6h引起p-p38的表达上调（P<0.05），24h引起p-JNK的表达上调（P<0.05）；与对照组相比，JNK抑制剂SP600125引起的TSCCA细胞的迁移数目减少（SP600125： 94.5±15.5，对照： 142.5±20.8，P<0.05），侵袭数目也减少（SP600125： 52.5±16.5，对照： 118.4±38.1，P<0.05）。结论 OSCC神经新生与疾病的进展密切相关，神经递质CGRP可能通过磷酸化JNK促进OSCC细胞的迁移和侵袭，从而促进OSCC的进展。

Abstract:

Objective To investigate the role of neurogenesis in oral squamous cell carcinomas(OSCC) and its related mechanism. Methods The expression of pan-neuronal marker protein gene product(PGP) 9.5 was detected by immunohistochemistry in the tumor tissues in 167 cases of OSCC. The effect of calcitonin gene related peptide(CGRP) on migration and invasion of human tongue SCC TSCCA cells was examined by Transwell assay. The effect of CGRP on the expression of phosphorylation of extracellular regulatory protein kinase(ERK), p38 and c-Jun N-terminal kinase(JNK) was examined by Western blot. The effect of ERK/p38/JNK inhibitors on CGRP-induced cell migration and invasion was examined by Transwell assay. Results The PGP9.5-immunoreactive nerve fibers were observed in 88%(147/167) of OSCC cases. The expression of PGP9.5 was correlated with tumor grade(r=0.425, P<0.001), neural invasion(r=0.166, P<0.05), shorter survival(r=0.186, P<0.05) . CGRP promoted the migration(165.4±14.2 vs 110.2±5.3, P<0.001) and invasion(68.3±23.5 vs 12.8±2.8, P<0.001) of TSCCA cells. The expression of p-ERK was increased 1h after CGRP treatment(P<0.001). The expression of p-p38 was increased 6h after CGRP treatment(P<0.05). The expression of p-JNK was increased 24h after CGRP treatment(P<0.05). JNK inhibitor SP600125 attenuated CGRP-induced migration(94.5±15.5 vs 142.5±20.8, P<0.05）and invasion(52.5±16.5 vs 118.4±38.1, P<0.05) of TSCCA cells. Conclusion Neurogenesis is associated with progress of OSCC. CGRP promotes the migration and invasion of OSCC cells through JNK. These indicate that neurotransmitters released from the nerve terminals in OSCC promote the migration and invasion of cancer cells, which leads to the progress of OSCC.