title: S100A4 (Mts1) gene overexpression is associated with invasion and metastasis of papillary thyroid carcinoma.
abstract: Tumour cell invasion and metastasis are the hallmark of malignant neoplasm. S100A4 is a member of small calcium-binding protein family and is involved in the cell proliferation and cancer progression. S100A4 is capable of inducing metastasis in animal models and is associated with aggressive phenotype of human tumours. We previously identified S100A4 as a candidate gene involved in anaplastic thyroid cancer metastasis by microarray analysis. To further determine whether S100A4 overexpression is associated with thyroid tumour invasion and metastasis, in the present study, we examined S100A4 gene expression in six benign multinodular goitres (MNG) and 28 matched samples of adjacent normal thyroid tissue (N), primary (T) and metastatic (M) papillary thyroid carcinomas (PTC) by immunohistochemistry and real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis. This gave us the advantage of directly comparing levels of S100A4 expression within the same genetic background. Using immunohistochemistry, we found that high levels of S100A4 were detected in 24 of 28 (86%) PTC specimens and their local regional lymph node or distant metastases. No S100A4 staining was observed in normal thyroid tissues and simple MNG. However, in MNG coexistent with PTC, moderate focal staining could be found in 11 of 15 MNG adjacent to PTC. The S100A4 was stained more intensely in invading fronts than in central portions of both T and M. Real-time RT-PCR analysis of primary tumours and their matched lymph node metastasis demonstrated that significantly higher S100A4 transcripts were present in metastatic tumours as compared to the primary tumours (P<0.01). These data suggest that overexpression of S100A4 is associated with thyroid tumour invasion and metastasis and it may be a potential target for therapeutic intervention.
authors.affiliation: Department of Genetics, King Faisal Specialist Hospital and Research Center, PO Box 3354, Riyadh 11211, Saudi Arabia.
authors.forename: M
authors.initials: M
authors.lastname: Zou
authors.forename: R S
authors.initials: RS
authors.lastname: Al-Baradie
authors.forename: H
authors.initials: H
authors.lastname: Al-Hindi
authors.forename: N R
authors.initials: NR
authors.lastname: Farid
authors.forename: Y
authors.initials: Y
authors.lastname: Shi
mesh_terms: D002291:Carcinoma, Papillary / Q000235:genetics* / Q000473:pathology*; D016022:Case-Control Studies; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006042:Goiter / Q000235:genetics / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins / Q000096:biosynthesis* / Q000235:genetics; D015854:Up-Regulation
chemical_list: D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C077591:S100A4 protein, human