Human melanoma cells express functional receptors for thyroid-stimulating hormone
Julie A Ellerhorst1, Aresu Sendi-Naderi, Marilyn K Johnson
1Department of Experimental Therapeutics, Unit 362, University of Texas, MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas, USA. jaellerh@mdanderson.org
Endocrine-Related Cancer
|December 13, 2006
Summary
Elevated thyroid-stimulating hormone (TSH) in hypothyroidism may promote melanoma growth. TSH receptors are present on melanoma cells, and TSH stimulates their proliferation, indicating TSH is a melanoma growth factor.
Area of Science:
- Endocrinology
- Dermatology
- Oncology
Background:
- Hypothyroidism is prevalent in cutaneous melanoma patients.
- A pathologic hormonal environment, specifically elevated TSH, may drive melanoma progression.
Purpose of the Study:
- To investigate if thyroid-stimulating hormone (TSH) stimulates melanoma cell growth.
- To determine the expression and function of TSH receptors (TSHR) in melanocytic lesions.
Main Methods:
- TSHR expression analysis in benign nevi, dysplastic nevi, and melanomas using immunofluorescence, western blotting, and RT-PCR.
- Assessment of TSHR functionality via cAMP formation and MAPK pathway activation.
- Melanoma cell proliferation assays in response to TSH.
Main Results:
- TSHR are expressed in nearly all melanocytic lesions, with increased expression in malignant and pre-malignant types.
- TSHR are functional in melanoma cells, responding to TSH by activating cAMP and MAPK pathways.
- TSH significantly stimulates proliferation of cultured melanoma cells but not melanocytes.
Conclusions:
- TSH acts as a growth factor for human melanoma.
- TSHR expression and functionality in melanoma have significant clinical implications for melanoma prevention and treatment.
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