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

Abstract

Objective To 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). Methods BRAF 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. Results BRAF 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. Conclusion BRAF 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. Key words: Papillary thyroid microcarcinoma; Galectin-3; Cytokcratin 19; V-raf murine sarcoma viral oncogene homolog B1