Murine Prostate Micro-dissection and Surgical Castration

Summary

This manuscript describes the protocols for prostate micro-dissection and surgical castration in the laboratory mouse. We also depict representative results produced by these protocols. Finally, we discuss the advantages and utilization of these protocols.

Abstract

Mouse models are used extensively to study prostate cancer and other diseases. The mouse is an excellent model with which to study the prostate and has been used as a surrogate for discoveries in human prostate development and disease. Prostate micro-dissection allows consistent study of lobe-specific prostate anatomy, histology, and cellular characteristics in the absence of contamination of other tissues. Testosterone affects prostate development and disease. Androgen deprivation therapy is a common treatment for prostate cancer patients, but many prostate tumors become castration-resistant. Surgical castration of mouse models allows for the study of castration resistance and other facets of hormonal biology on the prostate. This procedure can be coupled with testosterone reintroduction, or hormonal regeneration of the prostate, a powerful method to study stem cell lineages in the prostate. Together, prostate micro-dissection and surgical castration opens up a multitude of opportunities for robust and consistent research of prostate development and disease. This manuscript describes the protocols for prostate micro-dissection and surgical castration in the laboratory mouse.

Introduction

The prostate is the most common site of cancer in men in the US. Nearly 220,000 men each year will be diagnosed with prostate cancer, and approximately 27,000 men will succumb to their disease ¹. Men have a 1 in 7 lifetime risk of a prostate cancer diagnosis in the US ¹. Benign prostate hyperplasia (BPH), an age-related noncancerous enlargement of the prostate, is also a widespread condition, affecting over 80% of men over 80 ². As such, the prostate is the focus of considerable research.

Mouse models have been used widely to study diseases of the prostate ³. Overall, the mouse prostate is an exce....

Protocol

This protocol meets and follows the guidelines set by the Johns Hopkins University Institutional Animal Care and Use Committee.

1. Micro-dissecting a Mouse Prostate

1. Euthanize the mouse by carbon dioxide asphyxiation or an alternative approved method in accordance with institutional animal care and use guidelines.
2. Pin the mouse in a supine position to a dissection board by putting a pin through each of the four paws.
3. Spray the abdomen with 70% ethanol.
4. Hold the skin of the lower abdomen with forceps, and use scissors to cut through the skin and peritoneum approximately 1 cm anterior to the opening of the penis, careful n....

Results

All six prostate lobes were removed from a mouse via prostate micro-dissection (Figure 1). The complete urogenital tract (UGT) is composed of all prostate lobes, the bladder, seminal vesicles, and the urethra (Figure 1a). The vas deferens attaches to the urethra, but is unnecessary for prostate micro-dissection, and can thus be detached before removal of the UGT by cutting the urethra (Figure 1b-1c). The urogenital tract will remain toget.......

Discussion

Prostate micro-dissection allows for lobe-specific experimentation and analysis of the mouse prostate (Figure 1). In genetically engineered mouse models, phenotypes may be seen in one lobe that is not seen in others. Also, for histological analysis, this protocol assures that the maximum amount of pure prostate tissue can be sectioned and stained, without other urogenital tract tissues present in the section. Finally, for single-cell experiments, this protocol allows for isolation of almost pure prostate.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Surgical tools	Roboz	Various
Formaldehyde	Sigma	F8775
OCT medium	VWR	25608-930	Must be placed on dry ice to freeze, and stored at -80 °C
PBS	Life Technologies	10010
Isoflurane	Johns Hopkins		Also available from vendors online
Cautery Pen	Medline	ESCT002
Silk suture	AD Surgical	M-S330R19
Surgical Wound Clips	Roboz	RS-9265