Rat somatic genome editing enables ER+ breast cancer modeling

W Wen Bu (Lester and Sue Smith Breast Center, Baylor College of Medicine) T Tobie D. Lee (Lester and Sue Smith Breast Center, Baylor College of Medicine) M Meenakshi Anurag (Lester and Sue Smith Breast Center, Baylor College of Medicine) Y Yongchao Dou (Lester and Sue Smith Breast Center, Baylor College of Medicine) Y Yunfeng Ding (Lester and Sue Smith Breast Center, Baylor College of Medicine) Z Zhiao Shi (Lester and Sue Smith Breast Center, Baylor College of Medicine) R Ruixin Xu (Lester and Sue Smith Breast Center, Baylor College of Medicine) L Lillian He (Lester and Sue Smith Breast Center, Baylor College of Medicine) A Alexandria Z. Bu (Lester and Sue Smith Breast Center, Baylor College of Medicine) C Chandandeep Nagi (Department of Pathology, Baylor College of Medicine) C Carolina Gutierrez (Lester and Sue Smith Breast Center, Baylor College of Medicine) J Jing Wang (Hunan Cancer Hospital Changsha China) S Susan G. Hilsenbeck (Lester and Sue Smith Breast Center, Baylor College of Medicine) C Chonghui Cheng (Lester and Sue Smith Breast Center, Baylor College of Medicine) B Bing Zhang S Shixia Huang (Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine) J Jianming Xu (State Key Laboratory of Soil Pollution Control and Safety,) C C. Kent Osborne (Lester and Sue Smith Breast Center, Baylor College of Medicine) A Arun Sreekumar (Department of Molecular and Cellular Biology, Baylor College of Medicine) E Eric C. Chang (Lester and Sue Smith Breast Center, Baylor College of Medicine) C Chad J. Creighton (Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine) X Xiang H.-F. Zhang (Lester and Sue Smith Breast Center, Baylor College of Medicine) Y Yi Li

Abstract

Genetically engineered mouse models have advanced cancer research, but they fail to mimic some human diseases. Rats offer a powerful alternative for modeling human cancers that are inadequately represented in mice, yet their use has been constrained by technical barriers to genome editing. Here, we report somatic genome editing in rats and apply this approach to model estrogen receptor (ER)-positive breast cancer, which accounts for approximately 70% of human cases but remains poorly represented in mice. The resulting rat tumors reproduce hallmarks of human ER+ breast cancer, including ductal histology, hormone responsiveness, and immune microenvironment features. By contrast, identical genetic alterations in mice failed to yield ER+ tumors, underscoring critical species differences in tumorigenesis. Together, this work establishes a versatile platform for the rapid generation of clinically relevant rat tumor models, opening avenues to study tumor biology, therapeutic response, and immune interactions in cancer subtypes previously inaccessible to experimental modeling.

Article Details

Volume / Issue Vol. 123, Issue 26
Published June 30, 2026
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (23)

W

Wen Bu

Lester and Sue Smith Breast Center, Baylor College of Medicine

T

Tobie D. Lee

Lester and Sue Smith Breast Center, Baylor College of Medicine

M

Meenakshi Anurag

Lester and Sue Smith Breast Center, Baylor College of Medicine

Y

Yongchao Dou

Lester and Sue Smith Breast Center, Baylor College of Medicine

Y

Yunfeng Ding

Lester and Sue Smith Breast Center, Baylor College of Medicine

Z

Zhiao Shi

Lester and Sue Smith Breast Center, Baylor College of Medicine

R

Ruixin Xu

Lester and Sue Smith Breast Center, Baylor College of Medicine

L

Lillian He

Lester and Sue Smith Breast Center, Baylor College of Medicine

A

Alexandria Z. Bu

Lester and Sue Smith Breast Center, Baylor College of Medicine

C

Chandandeep Nagi

Department of Pathology, Baylor College of Medicine

C

Carolina Gutierrez

Lester and Sue Smith Breast Center, Baylor College of Medicine

J

Jing Wang

Hunan Cancer Hospital Changsha China

S

Susan G. Hilsenbeck

Lester and Sue Smith Breast Center, Baylor College of Medicine

C

Chonghui Cheng

Lester and Sue Smith Breast Center, Baylor College of Medicine

B

Bing Zhang

S

Shixia Huang

Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine

J

Jianming Xu

State Key Laboratory of Soil Pollution Control and Safety,

C

C. Kent Osborne

Lester and Sue Smith Breast Center, Baylor College of Medicine

A

Arun Sreekumar

Department of Molecular and Cellular Biology, Baylor College of Medicine

E

Eric C. Chang

Lester and Sue Smith Breast Center, Baylor College of Medicine

C

Chad J. Creighton

Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine

X

Xiang H.-F. Zhang

Lester and Sue Smith Breast Center, Baylor College of Medicine

Y

Yi Li