Increased Pleiotrophin Concentrations in Papillary Thyroid Cancer

Area of Science:

• Endocrinology
• Oncology
• Molecular Biology

Background:

• Thyroid nodules are common, with a 5% malignancy rate.
• Pleotrophin (PTN), a growth factor, is overexpressed in many cancers.
• PTN expression in papillary thyroid cancer (PTC) was previously unknown.

Purpose of the Study:

• To investigate Pleotrophin (PTN) expression in papillary thyroid cancer (PTC).
• To determine if the PTN to thyroglobulin (Tg) ratio can differentiate between malignant and benign thyroid nodules.

Main Methods:

• Analyzed ex vivo fine-needle aspiration (FNA) samples from 74 thyroidectomy patients (79 benign, 23 PTC).
• Assayed PTN and thyroglobulin (Tg) concentrations in FNA samples.
• Utilized immunohistochemistry (IHC) on tissue sections to examine PTN localization.

Main Results:

• The PTN/Tg ratio was significantly higher in PTCs (16 ± 6 ng/mg) compared to benign nodules (0.3 ± 0.1 ng/mg).
• This elevated PTN/Tg ratio was also observed in follicular variant PTC.
• Immunohistochemistry confirmed cytoplasmic PTN localization in PTC cells.

Conclusions:

• The PTN to Tg ratio is elevated in PTC, including the follicular variant, compared to benign thyroid nodules.
• Measurement of the PTN/Tg ratio may offer valuable diagnostic and prognostic information for thyroid nodules.