Intra-Cardiac Injection of Human Prostate Cancer Cells to Create a Bone Metastasis Xenograft Mouse Model

Summary

Here, we present a protocol for the intra-cardiac injection of human prostate cancer cells to generate a mouse model with bone metastasis lesions.

Abstract

As the most common male malignancy, prostate cancer (PC) ranks second in mortality, primarily due to a 65%-75% bone metastasis rate. Therefore, it is essential to understand the process and related mechanisms of prostate cancer bone metastasis for developing new therapeutics. For this, an animal model of bone metastasis is an essential tool. Here, we report detailed procedures to generate a bone metastasis mouse model via intra-cardiac injection of prostate cancer cells. A bioluminescence imaging system can determine whether prostate cancer cells have been accurately injected into the heart and monitor cancer cell metastasis since it has great advantages in monitoring metastatic lesion development. This model replicates the natural development of disseminated cancer cells to form micro-metastases in the bone and imitates the pathological process of prostate cancer bone metastasis. It provides an effective tool for further exploration of the molecular mechanisms and the in vivo therapeutic effects of this disease.

Introduction

Prostate cancer is the most frequent cancer in men in 112 countries and ranks second for mortality in higher human development index countries^1,2. Most deaths in prostate cancer patients are caused by metastasis, and about 65%-75% of the cases will develop bone metastasis^3,4. Therefore, prevention and treatment of prostate cancer bone metastases are urgently needed to improve the clinical outcome of prostate cancer patients. The animal model of bone metastasis is an indispensable tool for exploring the multistage process and molecular mechanisms involv....

Protocol

Six to eight week old male BALB/c athymic mice (n = 10) were housedin individually ventilated mice cages (5 mice/cage) in a specific-pathogen-free (SPF) animal room under the conditions of 12 h light/dark cycle, with free access to SPF feed and sterile water. Mice were adaptively fed for a week before the experiments.All animal experiments were approved by the animal welfare committee of Shanghai University of Traditional Chinese Medicine.

1. Cell preparation

1. On the day of prostate cancer cell injection, wash 80%-90% confluent luciferase labeled PC-3 cells (PC-3-luciferase) cultured in a 10 cm cell culture dish ....

Results

Bioluminescence imaging offers tremendous advantages in monitoring the metastatic lesion development for an intra-cardiac injection model. Soon after the cancer cell injection (within 24 h), bioluminescence imaging was used to visualize the cancer cells entering the general circulation (Figure 3A). Obvious bioluminescence signaling all over the body will be seen when the cancer cells are injected into the arterial circulation properly. Data from mice showing bioluminescence signals only at t.......

Discussion

Intra-cardiac injection of human prostate cancer cells to generate bone metastasis is an ideal mouse model for exploring the functions and mechanisms of prostate cancer bone metastasis and evaluating the therapeutic efficacy. Studies have shown that bone damage most likely occurs in the proximal tibia and the distal femur¹⁷, which may be due to their high vascularization and metabolic activity.

Since bone metastasis is a frequently observed metastatic lesion in breast c.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
1 mL syringes and needles	Shandong Weigao Group Medical Polymer Co., Ltd	20200411	The cells were injected into the ventricles of mice
Anesthesia machine	Shenzhen RWD Life Technology Co., Ltd	R500IP	Equipment for anesthetizing mice
Automatic cell counter	Shanghai Simo Biological Technology Co., Ltd	IC1000	For counting cells
BALB/c athymic mice	Shanghai SLAC Laboratory Animal Co, Ltd.	Male	6-8 week old, male mice
Bioluminescence imaging system	Shanghai Baitai Technology Co., Ltd	Vieworks	For tracking the tumor growth and pulmonary metastasis if the injected cells are labeled by luciferase
Centrifuge tube (15 mL, 50 mL)	Shanghai YueNian Biotechnology Co., Ltd	430790, Corning
EDTA solution	Wuhan Xavier Biotechnology Co., Ltd	G1105	For decalcification of bone tissure
F-12 medium	Shanghai YueNian Biotechnology Co., Ltd	21700075, GIBCO	Cell culture medium
Formalin solution	Shanghai YueNian Biotechnology Co., Ltd	BL539A	For fixing the specimen of each mouse
Isoflurane	Shenzhen RWD Life Technology Co., Ltd	VETEASY	For anesthesia
Lipofectamine 2000	Shanghai YueNian Biotechnology Co., Ltd	11668027, Thermo fisher	Plasmid transfection reagent
PC-3 cell line	Cell Bank of Chinese Academy of Sciences	TCHu 158	Prostate cancer cell line
Phosphate-buffered saline	Beyotime Biotechnology	ST447	Wash the human osteosarcoma cells
Trypsin (0.25%)	Shanghai YueNian Biotechnology Co., Ltd	25200056, Gibco	For detaching the cells
Vector (pLV-luciferase)	Shanghai YueNian Biotechnology Co., Ltd	VL3613	Plasmid for transfection
X-ray imaging system	Brook (Beijing) Technology Co., Ltd	FX PRO	For obtaining x-ray images to detect tumor growth
μCT80	Shenzhen Fraun Technology Service Co., Ltd	Scanco Medical AG,Switzerland	For detection of bone destruction. The mico-CT is equipped with 3DCalc, cone reconstruction,  and μCT Ray V3.4A model visualization software.