High levels of Nm23 gene expression in advanced stage of thyroid carcinomas.
The product of Nm23 gene has been proposed as a candidate tumour metastasis suppressor protein. A strong association has been observed between reduced expression of Nm23 gene and acquisition of metastatic behaviour in some tumour cells including breast cancer and melanoma, but not in others such as colon cancer, neuroblastoma, and cervical cancer. In the present study, we examined the abundance of Nm23 mRNA in 39 thyroid tissue specimens including five multinodular goitres, one follicular adenoma, 26 papillary and three follicular carcinomas, and four anaplastic carcinomas. Nm23 was found to be expressed in all the tissue specimens. The expression was, however, variable in different stages of thyroid carcinoma. In stages I through III of differentiated thyroid carcinoma, the average level of Nm23 gene expression was comparable to that in multinodular goitres. In advanced stage of thyroid carcinoma (stage IV and anaplastic), 2-fold increase of Nm23 expression was noted. No mutations were found in the coding region of the gene. Nm23 mRNA level cannot, therefore, be used as a marker of low metastatic potential in thyroid carcinomas. The association of high level Nm23 expression with anaplastic thyroid carcinoma suggests its correlation with rapid cell proliferation.
Department of Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia.
M
M
Zou
Y
Y
Shi
S
S
al-Sedairy
N R
NR
Farid
D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D015342:DNA Probes; D004273:DNA, Neoplasm / Q000032:analysis / Q000235:genetics; D015870:Gene Expression; D016147:Genes, Tumor Suppressor; D006801:Humans; D008969:Molecular Sequence Data; D020559:Monomeric GTP-Binding Proteins; D054778:NM23 Nucleoside Diphosphate Kinases; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009701:Nucleoside-Diphosphate Kinase / Q000096:biosynthesis; D009838:Oligodeoxyribonucleotides; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D012337:RNA, Ribosomal, 18S / Q000032:analysis; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000473:pathology; D014157:Transcription Factors / Q000032:analysis / Q000096:biosynthesis*
D015342:DNA Probes; D004273:DNA, Neoplasm; D054778:NM23 Nucleoside Diphosphate Kinases; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D012337:RNA, Ribosomal, 18S; D014157:Transcription Factors; C517938:NME1 protein, human; D009701:Nucleoside-Diphosphate Kinase; D020559:Monomeric GTP-Binding Proteins