Document Type

Dissertation

Degree

Doctor of Philosophy (PhD)

Department

Biology

First Advisor's Name

Lidia Kos

First Advisor's Committee Title

Committee Chair

Second Advisor's Name

Lou Kim

Second Advisor's Committee Title

Committee Member

Third Advisor's Name

M. Alejandro Barbieri

Third Advisor's Committee Title

Committee Member

Fourth Advisor's Name

Nikolas Tsoukias

Fourth Advisor's Committee Title

Committee Member

Fifth Advisor's Name

Zhao-Jun Liu

Fifth Advisor's Committee Title

Committee Member

Keywords

Melanoma, Endothelin 3, Endothelin receptor B, metastasis

Date of Defense

11-10-2015

Abstract

Endothelin receptor b (Ednrb) and its ligand Endothelin 3 (Edn3) have been implicated in melanoma. Several studies have shown an upregulation of EDNRB and EDN3 at both the protein and mRNA levels, as melanoma becomes more aggressive. This study investigated the putative role played by Edn3 over-expression in melanoma progression and angiogenesis in vivo. We crossed Tg(Grm1)Epv transgenic mice that aberrantly express metabotropic glutamate receptor1 under the Dopachrome tautomerase promoter, leading to spontaneous melanocytic lesions in the ears and tails that do not metastasize, with transgenics that overexpress Edn3 under the Keratin 5 promoter (K5-Edn3) or overexpress Ednrb in melanocytes (Tg(Ednrb)1Lk). In both the Tg(Grm1)Epv/K5-Edn3 and Tg(Grm1)Epv/Tg(Ednrb)1Lk mice, tumors appeared earlier and grew significantly larger and faster when compared to Tg(Grm1)Epv mice. Approximately eighty-one percent of Tg(Grm1)Epv/ K5-Edn3 mice and 76% of Tg(Grm1)Epv/Tg(Ednrb)1Lk mice had pigmented lesions in distant organs such as the lung and brain. Real-Time PCR analysis showed higher expression levels of genes involved in cell-cell and cell-matrix interactions and angiogenesis in lesions of Tg(Grm1)Epv/K5-Edn3 when compared to controls. Considering the rapid tumor growth rate of in the Tg(Grm1)Epv/K5-Edn3 mice, differences in the angiogenic response compared to control mice were investigated. Immunofluorescence analysis with the endothelial cell marker CD31 showed that there were more endothelial cells per tumor area in the Tg(Grm1)Epv/K5-Edn3 mice than the controls. Proteome analysis showed that the Dct-Grm1/K5-Edn3 mice had significant increases in other angiogenic related genes such as Angiogenin, CXCL 16 and Endoglin, when compared to controls, while real time PCR analysis of tail tumors also showed higher expression levels of angiogenic related genes such as Hif-1α. The results of this study showed that the EDNRB/EDN3 axis is sufficient to alter the kinetics of melanocytic tumors’ progression, lead them to a fully malignant state, and increase the tumor angiogenic response.

Identifier

FIDC000185

Share

COinS
 

Rights Statement

Rights Statement

In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/
This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).