甲状腺乳头状微小癌中鼠类肉瘤滤过性毒菌致癌同源体B1基因V600E位点突变及半乳糖凝集素-3、间皮表面微绒毛抗原、细胞角蛋白19表达特征研究

V-raf murine sarcoma viral oncogene homolog B1 V600E mutation and the expression of galectin-3, cytokcratin 19, MK in papillary thyroid microcarcinoma

目的观察甲状腺乳头状微小癌（PTMC）组织中鼠类肉瘤滤过性毒菌致癌同源体B1（BRAF）基因V600E位点突变及半乳糖凝集素-3（Gal-3）、间皮表面微绒毛抗原（MC）、细胞角蛋白19（CK19）的表达特征，探讨Gal-3、MC、CK19表达与BRAF基因V600E位点突变的关系。方法应用实时定量聚合酶链反应（Real-time PCR）检测BRAF基因V600E位点突变，应用免疫组织化学检测148例PTMC、74例甲状腺良性疾病（49例结节性甲状腺肿、25例甲状腺腺瘤）中Gal-3、MC、CK19蛋白表达，分析这些蛋白与PTMC患者临床病理特征的关系。结果PTMC组织中BRAF突变率明显高于甲状腺良性疾病（67.6%比4.1%，P＝0.000）；Gal-3、MC、CK19在PTMC中的表达明显高于甲状腺良性疾病（91.2%比8.1%、83.8%比13.5%、95.9%比4.1%，P＝0.000）；Gal-3、MC、CK19蛋白表达与颈淋巴结转移明显相关（P＝0.007、0.000、0.036）；BRAF V600E基因突变与包膜侵犯、颈淋巴结转移明显相关（P＝0.000、0.005）；联合检测BRAF＋Gal-3、BRAF＋MC、BRAF＋CK19诊断PTMC的灵敏度分别为93.2%、85.1%、96.6%，并以BRAF＋CK19组合检测诊断PTMC的灵敏度最高。结论BRAF基因V600E位点突变及Gal-3、MC、CK19蛋白表达有助于PTMC的诊断；联合检测BRAF基因V600E位点突变及Gal-3、MC、CK19蛋白表达有助于提高PTMC的诊断；Gal-3、MC、CK19蛋白的表达可提示颈部淋巴结转移；BRAF基因的突变可能使肿瘤更具有侵袭性，更容易发现淋巴结转移。

ObjectiveTo explore the significance of the expression levels of galectin-3 （Gal-3）, MC and cytokcratin 19 （CK19） proteins, and V-raf murine sarcoma viral oncogene homolog B1 （BRAF） V600E mutation in papillary thyroid microcarcinoma （PTMC）.MethodsBRAF gene V600E mutation was tested using real-time quantitative polymerase chain reaction （Real-time PCR） and the protein expression levels of Gal-3, MC and CK19 were detected using immunohistochemistry in both PTMC and thyroid benign lesions.ResultsBRAF mutation rate in PTMC was significantly higher than in thyroid benign disease （67.6% vs. 4.1%, P=0.000）. The expression levels of Gal-3, MC and CK19 proteins in PTMC were significantly higher than those in thyroid benign lesions （91.2% vs. 8.1%, 83.8% vs. 13.5%, and 95.9% vs. 4.1, P=0.000）. The protein expression of Gal-3, MC and CK19 was associated with cervical lymphatic metastasis （P=0.007, 0.000, 0.036）. BRAF gene V600E mutation was associated with capsular invasion and cervical lymphatic metastasis （P=0.005, P=0.000）. The sensitivity of BRAF＋ Gal-3, BRAF＋ MC and BRAF＋ CK19 in PTMC was 93.2%, 85.1% and 96.6%, and combination of BRAF＋ CK19 showed the highest sensitivity in PTMC.ConclusionBRAF geneV600E mutation and the protein expression of Gal-3, MC and CK19 have important referenced value to PTMC. Combination of BRAF geneV600E mutation and the protein expression of Gal -3, MC and CK19 is helpful to improve the diagnosis of PTMC. The protein expression of Gal-3, MC and CK19 may remind cervical lymphatic metastasis. BRAF gene mutation may make the tumor more aggressive, and lymphatic metastasis can be found more easily.