Overexpression of MAMLD1 in Human and Dogs with Cushing's disease Open Access

Abstract

Cushing disease is a secondary hypercortisalism caused by adrenocorticotropic (ACTH) secreting pituitary adenomas. Similar to humans, dogs, also suffer from this disorder. In an effort to map common genomic features Cushing disease between of humans and beagles, we performed whole transcriptome RNA-Seq. Comparing Cushing pituitary adenomas to normal pituitary from humans and dogs, we identified 4 genes (MAMLD1, MNX1, RASEF, TBX19) to be significantly (P<0.05) overexpressed in both species. Immunohistochemistry of 31 additional human pituitary adenomas revealed MAMLD1 to be strongly positively expressed in the nucleus of ACTH secreting tumor cells which are normally absent in healthy pituitary tissues. Although our cohort is relatively small, this data presents new insights into the shared genetic profile of human and beagle Cushing's pituitary adenomas and provides a rationale for potential use of a beagle model in development of precision therapeutics. Although other genomic studies have been have been recently conducted in humans with Cushing's, our results provide the first insights into the comparative genomic characterization of Cushing's disease in humans and dogs with respect to MAMLD1 overexpression.

Table of Contents

Introduction : 1-3

Materials and Methods : 4

• Human cohort: 4
• Dog cohort: 4-5
• Nucleic acid extractions and sequencing: 5
• Human exome sequence analysis: 5
• RNA-sequencing analysis: 6
• Immunohistochemistry: 6
• Immunohistochemistry scoring: 6-7
• ACTH determination: 7
• Statistical analysis: 7

Results : 8

• Whole Exome Sequencing: 8-9
• RNA Sequencing: 9-11
• Immunohistochemistry: 11-12

Discussion : 13

• Whole Exome Sequencing: 13
• Recurrent mutations in deubiquitinating enzymes: 13-14
• RNA Sequencing: 14-16
• Proopionmelanocortin: 16
• Immunohistochemistry: 17
• Pathogenesis of CD with MAMLD1: 17-19

Figures and Graphs : 20

• Figure 1: Copy number variation: 20
• Figure 2: Unsupervised hierarchical clustering: 21
• Figure 3: Shared gene expression changes: 22
• Figure 4: RNA-seq boxplot comparison: 23
• Figure 5: Summary of Immunohistochemistry: 24
• Figure 6: Immunohistochemistry of MAMLD1: 25
• Figure 7: Proposed MAMLD1 interaction pathway: 26

References : 27-31

About this Honors Thesis

Rights statement

• Permission granted by the author to include this thesis or dissertation in this repository. All rights reserved by the author. Please contact the author for information regarding the reproduction and use of this thesis or dissertation.

School	Emory College
Department	Neuroscience and Behavioral Biology
Degree	BS
Submission	Honors Thesis
Language	English
Research Field	Biology, Endocrinology Biology, Genetics Health Sciences, Surgery
Keyword	MAMLD1 Cushing's disease Human and Canines Hypercortisolism IHC ACTH RNA-Seq Pituitary Adenoma
Committee Chair / Thesis Advisor	Oyesiku, Nelson M, Emory University
Committee Members	Antia, Rustom, Emory University Neill, Stewart G, Emory University Lennard, Paul R, Emory University Rossi, Michael R, Emory University

Last modified

Primary PDF

Thumbnail	Title	Date Uploaded	Actions
	Overexpression of MAMLD1 in Human and Dogs with Cushing's disease ()	2018-08-28 15:23:32 -0400	Press to Select an action Download

Supplemental Files

Thumbnail	Title	Date Uploaded	Actions