Implication of intracellular localization of transcriptional repressor PLZF in thyroid neoplasms
1 Department of Regional Medicine, Tottori University Faculty of Medicine, 86 Nishi-cho, Yonago 683-8503, Japan
2 Department of Molecular Medicine and Therapeutics, Division of Endocrinology and Metabolism, Tottori University Faculty of Medicine, 36-1 Nishi-cho, Yonago 683-8504, Japan
3 Department of Surgery, Division of Organ Regeneration Surgery, Tottori University Faculty of Medicine, 36-1 Nishi-cho, Yonago 683-8504, Japan
4 Division of Regenerative Medicine and Therapeutics, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Science, 86 Nishi-cho, Yonago 683-8503, Japan
5 Department of Medicine, Division of Metabolism and Biosystemic Science, Asahikawa Medical University, 1-1-1 Midorigaokahigashinijyo, Asahikawa 078-8510, Japan
6 Tottori Municipal Hospital, 1-1 Matoba, Tottori 680-8501, Japan
BMC Endocrine Disorders 2014, 14:52 doi:10.1186/1472-6823-14-52Published: 3 July 2014
Promyelocytic leukaemia zinc finger (PLZF) is a transcriptional repressor that was originally isolated from a patient with promyelocytic leukaemia. PLZF also affects key elements for cell cycle progression, such as cyclin A, and can affect the tumourigenicity of various cancers. Thus far, the behaviour of PLZF in thyroid carcinoma remains unclear.
We analysed the expression profile of PLZF in different types of benign and malignant thyroid lesions as well as in normal thyroid tissue. Specifically, we examined PLZF expression in normal thyroid (N; n = 4), adenomatous lesion (AL; n = 5), follicular adenoma (FA; n = 2), papillary thyroid carcinoma (PTC; n = 20), and anaplastic thyroid carcinoma (ATC; n = 3) samples. PLZF expression was estimated by western blotting and immunohistochemical (IHC) staining.
PLZF was expressed in all samples of thyroid lesions examined. In N, AL, and FA, PLZF was mainly localized in the nucleus. In contrast, in PTC and ATC, PLZF was mainly expressed in the cytosol with high intensity. In more detail, the cytoplasmic IHC scores in PTC with capsular invasion (CI) and lymph node (LN) metastasis were higher than those in PTC without CI and LN metastasis.
PLZF shows different subcellular localizations among PTC, ATC, and other thyroid lesions. Furthermore, high cytoplasmic expression of PLZF may be correlated with CI and LN metastasis in thyroid carcinoma. The present report is the first to describe the implications of intracellular PLZF expression in thyroid carcinomas.