Background: The cellular retinoic acid-binding protein II (CRABPII) and epidermal fatty acid-binding protein (E-FABP) both serving as the transport protein of retinoic acid (RA), through RA signal transduction pathway, commit the cell to opposite fate, apoptosis or survival. The aim of this study is to investigate the expression of CRABPII and E-FABP and significance in non-small cell lung cancer (NSCLC) and their lymph node metastases with tissue microarray technique.
Methods: CRABPII and E-FABP proteins were detected in 54 normal lung tissues, 287 primary NSCLC tissues and 112 lymph node metastatic tissues by SP method of immunohistochemical staining.
Results: The expression level of CRABPII in the primary lesions was relevant to the gender of NSCLC patients, the metastasis and TNM staging of NSCLC (P<0.05), while the expression level of E-FABP was related to the grading and metastasis of NSCLC (P<0.05). The positive expression rate of E-FABP in NSCLC primary lesion was remarkably higher than that in adjacent normal lung tissues and lymph node metastases, respectively (P<0.05). The expression level of E-FABP had a recognizable advantage over that of CRABPII in NSCLC primary lesions (P<0.05). The differential expressions between CRABPII and E-FABP was correlated with the tumor size, grading, metastasis, TNM staging of NSCLC (P<0.05). The larger the tumor was and the later the TNM staging was, along with cancer metastasis, the more likely the expression of E-FABP would dominate. The expression of CRABPII and difference expression between CRABPII and E-FABP were closely related to the prognosis of NSCLC patients based on Kaplan-Meier survival analysis.
Conclusions: E-FABP showed high exp ression in NSCLC, and the increased E-FABP expression may involved in the occurrence and development of NSCLC. CRABPII might have a negative effect in NSCLC progression, and its expression was negatively related to the prognosis of NSCLC patients.
背景与目的: 细胞视黄酸结合蛋白（cellular retinoic acid-binding protein Ⅱ, CRABPⅡ）和表皮型脂肪酸结合蛋白（epidermal fatty acid-binding protein, E-FABP）作为维甲酸（retinoic acid, RA）的转运蛋白，通过RA信号传导通路，从正反两方面影响细胞的增殖和凋亡。本研究旨在探讨CRABPII和E-FABP在非小细胞肺癌（non-small cell lung cancer, NSCLC）中的表达及意义。
方法: 利用组织芯片技术和免疫组织化学SP法检测54例正常肺组织、287例NSCLC原发癌组织以及103例淋巴结转移癌组织中CRABPII和E-FABP的表达。
结果: CRABPII在NSCLC原发癌组织中的表达与患者的性别、肿瘤的有无转移、TNM分期有关（P < 0.05）。E-FABP在NSCLC原发癌组织中的阳性表达率分别高于正常肺组织和淋巴结转移癌组织（P < 0.05）。在NSCLC原发癌组织中，E-FABP的表达与肿瘤的病理分级、有无转移有关（P < 0.05）。在NSCLC中，E-FABP的阳性表达较CRABPII占优势（P < 0.05），两种蛋白的差异性表达与肿瘤的大小、病理分级、有无转移、TNM分期有关（P < 0.05），瘤体愈大，肿瘤发生转移，临床分期愈晚，E-FABP的表达愈占优势。Kaplan-Meier单因素生存分析显示：CRABPII的表达、CRABPII与E-FABP的差异性表达与NSCLC患者的预后有关（P < 0.05）。
结论: E-FABP在NSCLC中高表达，其表达的增强可能与NSCLC的发生和演进有关；CRABPII可能在NSCLC的发展过程中起负向调节作用，CRABPII阴性表达患者术后生存率更高，对NSCLC患者预后的评估有一定价值。