Establishment and Characterization of Patient-Derived Xenograft Models of Anaplastic Thyroid Carcinoma and Head and Neck Squamous Cell Carcinoma

Summary

The present protocol establishes and characterizes a patient-derived xenograft (PDX) model of anaplastic thyroid carcinoma (ATC) and head and neck squamous cell carcinoma (HNSCC), as PDX models are rapidly becoming the standard in the field of translational oncology.

Abstract

Patient-derived xenograft (PDX) models faithfully preserve the histological and genetic characteristics of the primary tumor and maintain its heterogeneity. Pharmacodynamic results based on PDX models are highly correlated with clinical practice. Anaplastic thyroid carcinoma (ATC) is the most malignant subtype of thyroid cancer, with strong invasiveness, poor prognosis, and limited treatment. Although the incidence rate of ATC accounts for only 2%-5% of thyroid cancer, its mortality rate is as high as 15%-50%. Head and neck squamous cell carcinoma (HNSCC) is one of the most common head and neck malignancies, with over 600,000 new cases worldwide each year. Herein, detailed protocols are presented to establish PDX models of ATC and HNSCC. In this work, the key factors influencing the success rate of model construction were analyzed, and the histopathological features were compared between the PDX model and the primary tumor. Furthermore, the clinical relevance of the model was validated by evaluating the in vivo therapeutic efficacy of representative clinically used drugs in the successfully constructed PDX models.

Introduction

The PDX model is an animal model in which human tumor tissue is transplanted into immunodeficient mice and grows in the environment provided by the mice¹. Traditional tumor cell line models suffer from several disadvantages, such as the lack of heterogeneity, the inability to retain the tumor microenvironment, the vulnerability to genetic variations during repeated in vitro passages, and the poor clinical application^2,3. The main drawbacks of genetically engineered animal models are the potential loss of the genomic features of human tumors, the introduction of new unknown muta....

Protocol

All the animal experiments were performed in accordance with the Association for Assessment and Accreditation of Laboratory Animal Care guidelines and protocols approved by the Institutional Animal Care and Use Committee of West China Hospital, Sichuan University. NOD-SCID immunodeficient mice aged 4-6 weeks old (of both sexes) and female Balb/c nude mice aged 4-6 weeks old were used for the present study. The animals were obtained from a commercial source (see Table of Materials). The ethics committee of West China Hospital authorized the study with human subjects (protocol number 2020353). Each patient provided written informed consent.

Results

A total of 18 thyroid cancer specimens were transplanted, and five PDX models of thyroid cancer were successfully constructed (27.8% tumor take rate), including four cases of undifferentiated thyroid cancers and one case of anaplastic thyroid cancer. The correlation between the success rate of model construction and the age, gender, tumor diameter, tumor grade, and differentiation were analyzed. Although the model success rate of grade 4 tumor samples was higher than for samples with lower grades, and the success rate of.......

Discussion

This study has successfully established the subcutaneous PDX models of ATC and HNSCC. There are many aspects to pay attention to during the process of PDX model construction. When the tumor tissue is separated from the patient, it should be put into the ice box and sent to the laboratory for inoculation as soon as possible. After the tumor arrives at the laboratory, the operator must pay attention to maintaining a sterile field and practice aseptic procedures. For needle biopsy samples, because the tumor tissue is partic.......

Materials

Name	Company	Catalog Number	Comments
2.4 mm x 2.0 mm trocar	Shenzhen Huayang Biotechnology Co., Ltd	18-9065
Balb/c nude mice	Beijing Vital River Laboratory Animal Technology Co., Ltd.	401
Biosafety cabinet	Suzhou Antai	BSC-1300IIA2
Blade	Shenzhen Huayang Biotechnology Co., Ltd	18-0823
Centrifuge tube	Corning	430791/430829
Cryopreservation tube	Chengdu Dianrui Experimental Instrument Co., Ltd	/
Custodiol HTK-Solution	Custodiol	2103417
Dimethyl sulfoxide(DMSO)	SIGMA-ALORICH	D5879-500mL
Electronic balance	METTLER	ME104
Electronic digital caliper	Chengdu Chengliang Tool Group Co., Ltd	0-220
fetal bovine serum(FBS)	VivaCell	C04001-500
IBM SPSS Statistics 26	IBM
Ketamine	Jiangsu Zhongmu Beikang Pharmaceutical Co., Ltd	100761663
Lenvatinib	ApexBio	A2174
NOD SCID immunodeficient mice	Beijing Vital River Laboratory Animal Technology Co., Ltd.	406
Pen-Strep Solution	Biological Industries	03-03101BCS
Petri dish	WHB	WHB-60/WHB-100
Saline	Sichuan Kelun	W220051705
Scissor	Shenzhen Huayang Biotechnology Co., Ltd	18-0110
Tweezer	Shenzhen Huayang Biotechnology Co., Ltd	18-1241
Vet ointment	Pfizer Inc.	P10015353
Xylazine	Dunhua Shengda Animal Medicine Co., Ltd	070031777