title: Regulation of leptin receptor expression in human papillary thyroid cancer cells.
abstract: Epidemiological studies suggest an important link between obesity and thyroid cancer. The adipose tissue-derived polypeptide leptin acting via leptin receptor may modulate cell migration of thyroid cancer cells. Previously we have demonstrated that leptin receptor is overexpressed in papillary thyroid cancer and is associated with tumor aggressiveness. The present study was undertaken to explore the possible regulatory factors which would influence leptin receptor expression in papillary thyroid cancer cells. We found that DNA methyltransferase inhibitor (5-Aza-2'-deoxycytidine) and histone deacetylase inhibitor (trichostatin A) reduced leptin receptor expression. Conversely, insulin upregulated leptin receptor expression in a time- and dose-dependent manner. Hypoxia-mimicking agent (cobalt chloride) had no effect on leptin receptor expression. Taken together, our study provides evidence that epigenetic events and insulin stimulation take part in regulation of leptin receptor expression in papillary thyroid cancer cells.
authors.affiliation: Department of Surgery, Mackay Memorial Hospital, Taipei 10449, Taiwan.
authors.forename: Shih-Ping
authors.initials: SP
authors.lastname: Cheng
authors.forename: Chien-Liang
authors.initials: CL
authors.lastname: Liu
authors.forename: Yi-Chiung
authors.initials: YC
authors.lastname: Hsu
authors.forename: Yuan-Ching
authors.initials: YC
authors.lastname: Chang
authors.forename: Shih-Yuan
authors.initials: SY
authors.lastname: Huang
authors.forename: Jie-Jen
authors.initials: JJ
authors.lastname: Lee
mesh_terms: D015153:Blotting, Western; D002277:Carcinoma / Q000235:genetics / Q000378:metabolism*; D002291:Carcinoma, Papillary; D015687:Cell Hypoxia; D045744:Cell Line, Tumor; D019175:DNA Methylation / Q000187:drug effects; D015254:DNA Modification Methylases / Q000037:antagonists & inhibitors; D004273:DNA, Neoplasm / Q000378:metabolism*; D015536:Down-Regulation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000378:metabolism*; D009994:Osmolar Concentration; D054411:Receptors, Leptin / Q000378:metabolism*; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D004273:DNA, Neoplasm; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D007004:Hypoglycemic Agents; D007328:Insulin; C515448:LEPR protein, human; D009363:Neoplasm Proteins; D054411:Receptors, Leptin; D015254:DNA Modification Methylases