title: Establishment of an mKate2-Expressing Cell Line for Non-Invasive Real-Time Breast Cancer In Vivo Imaging.
abstract: OBJECTIVE
  Non-invasive real-time in vivo imaging experiments using mice as animal models have become crucial for understanding cancer development and treatment. In this study, we have developed and validated a new breast cancer cell line MDA-MB-435s that stably express a far-red fluorescence protein (mKate2) and that could serve as a highly valuable cell model for studying breast cancer detection and therapy using in vivo fluorescence imaging in nude mice.
  
  
  METHODS
  The new cell line (MDA-MB-435s-mKate2) was constructed by plasmid transfection. The stability and sensitivity of mKate2, and the cell biological activities, were tested in vitro using different experimental approaches. For its potential use in tumor growth research and drug therapy in vivo, MDA-MB-435s-mKate2 was validated using the immunocompromised Balb/c nude mice tumor model. In addition, the new cell line has been characterized as a luteinizing hormone-releasing hormone receptor (LHRHR) positive cell line.
  
  
  RESULTS
  Firstly, MDA-MB-435s-mKate2 has shown a stable chromosomal integration of the amplified mKate2 gene and good fluorescence sensitivity for detection using a fluorescence reflectance imaging (FRI) device. Compared to its parental cell line, no significant difference in cell migration, proliferation, and clone formation was observed in vitro. Secondly, using the quantification of tumor-fluorescence surface area in live animals, we were able to monitor and detect the tumor progress or tumor inhibition rate (by Paclitaxel treatment) non-invasively and in real-time. Furthermore, MDA-MB-435s-mKate2 has been positively tested for LHRHR; these findings open the possibility to use this cell line for future studies of breast cancer therapy based on LHRH analogs in vivo.
  
  
  CONCLUSIONS
  In the present research, we have successfully built the MDA-MB-435s-mKate2 cell line that can be used as a suitable cell model for breast cancer therapy and anti-cancer drug evaluation by non-invasive fluorescence imaging in mice.
authors.affiliation: Laboratory Animal Center, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.|Department of Biomedical Engineering, College of Engineering, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.
authors.forename: Ivan
authors.initials: I
authors.lastname: Vuletic
authors.affiliation: Laboratory Animal Center, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.
authors.forename: Jinghao
authors.initials: J
authors.lastname: Liu
authors.affiliation: Laboratory Animal Center, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.
authors.forename: Honglian
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Biomedical Engineering, College of Engineering, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.
authors.forename: Yichen
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Laboratory Animal Center, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Lei
authors.affiliation: Department of Biomedical Engineering, College of Engineering, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.
authors.forename: Changhui
authors.initials: C
authors.lastname: Li
authors.affiliation: Laboratory Animal Center, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.
authors.forename: Desheng
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Department of Biomedical Engineering, College of Engineering, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China.
authors.forename: Qiushi
authors.initials: Q
authors.lastname: Ren
authors.affiliation: Department of Biomedical Engineering, College of Engineering, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China. shf@pku.edu.cn.
authors.forename: Hongfang
authors.initials: H
authors.lastname: Sun
authors.affiliation: Laboratory Animal Center, Peking University, No. 5 Yiheyuan Road, Beijing, 100871, China. likejun@pku.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000628:therapy; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D061848:Optical Imaging
keywords: Fluorescence; Imaging; mKate2