Poorly differentiated
thyroid carcinoma (
PDTC) is a newly recognized histological type of malignant thyroid
tumor, accounting for about 2 - 13% of all
thyroid carcinomas.
PDTC is considered as a morphologically and biologically intermediate stage between well-differentiated
thyroid carcinoma and
anaplastic thyroid carcinoma.
PDTC preferentially manifests bone
metastases. We here established a cell line from a resected
tumor specimen from a 70-year-old male patient with
PDTC who presented with multiple bone
metastases. This new thyroid tumor cell line was designated as DH-14-3 and was subsequently grown in culture for several years. DH-14-3 cells express
thyroglobulin in the cytoplasm and thyroid transcription factor-1 in the nuclei, both
proteins of which are specific markers for the thyroid gland. Importantly,
triiodothyronine (T3) was detected in the cultured medium of DH-14-3 cells, in which, however,
thyroxine (T4) was undetectable. Moreover, DH-14-3 cells secreted
interleukin-8, transforming growth factor-β1,
vascular endothelial growth factor,
matrix metalloproteinase-1 and
parathyroid hormone-related protein, all of which may be responsible for the aggressiveness or bone
metastasis of
PDTC. Thus, the production of these
proteins may reflect the metastatic potential of this cell line. DH-14-3 cells also express
CXC chemokine receptor-4 and
epidermal growth factor receptor, and carry a missense mutation in the p53 tumor suppressor gene. In fact,
transplantation of DH-14-3 cells into the back of nude mice resulted in the formation of
tumors, thereby confirming the capability of
tumorigenesis. DH-14-3 cells may be useful for investigating the
biological features of
PDTC and will contribute to the therapeutic study of
thyroid cancer.