title: Expression of vascular endothelial growth factor-C in benign and malignant thyroid tumors.
abstract: In contrast to vascular endothelial growth factor (VEGF), which stimulates angiogenesis, VEGF-C is thought to stimulate lymphangiogenesis. The role of VEGF-C in thyroid cancer pathogenesis has not been clarified. One might expect a different pattern of VEGF-C expression in the various types of thyroid cancer because of their different means of metastases. In this investigation, we determined whether the differential expression of VEGF-C might explain the different propensity to lymph node metastasis in thyroid cancers. One hundred eleven normal and neoplastic thyroid tissues were analyzed by real-time quantitative PCR. Papillary thyroid cancers had a higher VEGF-C expression than other thyroid malignancies (P < 0.0005 ANOVA). Among the normal thyroid tissues from patients with malignant or benign thyroid diseases, there was no significant difference in VEGF-C expression. Paired comparison of VEGF-C expression between thyroid cancers and normal thyroid tissues from the same patients showed a significant increase of VEGF-C expression in papillary thyroid cancer (1.10 +/- 0.41 vs. 0.70 +/- 0.13; P = 0.001) and a significant decrease of VEGF-C expression in medullary thyroid cancer (0.11 +/- 0.13 vs. 0.78 +/- 0.29; P = 0.001). In contrast, there was no significant difference of VEGF-C expression between cancer and normal tissues in other types of thyroid cancer. In summary, VEGF-C expression is increased in papillary thyroid cancer, compared with paired normal thyroid tissues, but not in other thyroid cancers that are also prone to lymph node metastasis. The lymphangiogenic role of VEGF-C in thyroid cancers therefore appears to be complex and other factors are likely to be also involved.
authors.affiliation: Endocrine Surgical Oncology Fellows, University of California San Francisco, California 94143, USA.
authors.forename: Chung J
authors.initials: CJ
authors.lastname: Hung
authors.forename: David G
authors.initials: DG
authors.lastname: Ginzinger
authors.forename: Raza
authors.initials: R
authors.lastname: Zarnegar
authors.forename: Hajime
authors.initials: H
authors.lastname: Kanauchi
authors.forename: Mariwil G
authors.initials: MG
authors.lastname: Wong
authors.forename: Electron
authors.initials: E
authors.lastname: Kebebew
authors.forename: Orlo H
authors.initials: OH
authors.lastname: Clark
authors.forename: Quan-Yang
authors.initials: QY
authors.lastname: Duh
mesh_terms: D002291:Carcinoma, Papillary / Q000235:genetics / Q000378:metabolism; D018076:DNA, Complementary / Q000096:biosynthesis / Q000235:genetics; D016228:Endothelial Growth Factors / Q000096:biosynthesis* / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D005966:Glucuronidase / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D008198:Lymph Nodes / Q000737:chemistry / Q000378:metabolism; D008207:Lymphatic Metastasis / Q000235:genetics; D015347:RNA Probes; D012334:RNA, Neoplasm / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013964:Thyroid Neoplasms / Q000235:genetics / Q000378:metabolism*; D042582:Vascular Endothelial Growth Factor C
chemical_list: D018076:DNA, Complementary; D016228:Endothelial Growth Factors; D015347:RNA Probes; D012334:RNA, Neoplasm; D042582:Vascular Endothelial Growth Factor C; D005966:Glucuronidase