Sadia Quazi, Nhi Huynh, Angela Rigopoulos, Alexander McDonald, Uwe Ackermann, Andrew Mark Scott, Ingrid Julienne Georgette Burvenich
{"title":"Using 16α-[18F]-Fluoro-17β-Estradiol PET to Visualize Estrogen Receptor α Expression in Human Breast Cancer Xenografts in Female Ovariectomized Mice.","authors":"Sadia Quazi, Nhi Huynh, Angela Rigopoulos, Alexander McDonald, Uwe Ackermann, Andrew Mark Scott, Ingrid Julienne Georgette Burvenich","doi":"10.3791/67151","DOIUrl":null,"url":null,"abstract":"<p><p>To demonstrate how estrogen receptor alpha (ERα) positive breast cancer xenografts may be visualized in BALB/c nude mice using 16α-[18F]-fluoro-17β-estradiol (<sup>18</sup>F-FES) positron emission tomography (PET), ovariectomized BALB/c nude mice were injected with ERα-positive breast cancer cells (MCF-7, 3 × 10<sup>6</sup> cells; shoulder [n = 10] or 4<sup>th</sup> inguinal mammary fat pad [n = 10]) or ERα-negative breast cancer cells (MDA-MB-231, 1 × 10<sup>6</sup> cells; mammary fat pad [n = 5]). Mice harboring MCF-7 cells received subcutaneous injections of 20 µg of 17β-estradiol (20 µg/20 µL; corn oil:ethanol, 9:1) in the nape of their necks 2 days prior to cell injection, followed by daily injections five times per week for 5 weeks. Tumor volumes were measured according to the formula: (L*W<sup>2</sup>)/2 (L; length, W; width). Once tumor volumes reached approximately 100 mm<sup>3</sup>, 17β-estradiol injections were halted 2 days prior to mice receiving <sup>18</sup>F-FES for PET imaging to avoid competitive binding with ERα. Upon <sup>18</sup>F-FES administration via the lateral tail vein, PET/MRI was performed for 15 min at 1 h to 1.5 h post-injection. <sup>18</sup>F-FES uptake was not observed in ERα-negative, MDA-MB-231 tumor-bearing mice. <sup>18</sup>F-FES uptake was most pronounced in mice harboring MCF-7 tumors in the shoulder. In MCF-7 tumors grown in the inguinal mammary fat pad, <sup>18</sup>F-FES uptake was less visible, as the intestinal excretion pattern of <sup>18</sup>F-FES obscured the radioactivity detectable in these tumors. To use <sup>18</sup>F-FES PET as a tool to visualize ERα expression in ERα-positive breast xenografts, we demonstrate that the visibility of <sup>18</sup>F-FES uptake is clear in tumors located away from the abdominal region of mice, such as in the shoulder.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 217","pages":""},"PeriodicalIF":1.2000,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Jove-Journal of Visualized Experiments","FirstCategoryId":"103","ListUrlMain":"https://doi.org/10.3791/67151","RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MULTIDISCIPLINARY SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
To demonstrate how estrogen receptor alpha (ERα) positive breast cancer xenografts may be visualized in BALB/c nude mice using 16α-[18F]-fluoro-17β-estradiol (18F-FES) positron emission tomography (PET), ovariectomized BALB/c nude mice were injected with ERα-positive breast cancer cells (MCF-7, 3 × 106 cells; shoulder [n = 10] or 4th inguinal mammary fat pad [n = 10]) or ERα-negative breast cancer cells (MDA-MB-231, 1 × 106 cells; mammary fat pad [n = 5]). Mice harboring MCF-7 cells received subcutaneous injections of 20 µg of 17β-estradiol (20 µg/20 µL; corn oil:ethanol, 9:1) in the nape of their necks 2 days prior to cell injection, followed by daily injections five times per week for 5 weeks. Tumor volumes were measured according to the formula: (L*W2)/2 (L; length, W; width). Once tumor volumes reached approximately 100 mm3, 17β-estradiol injections were halted 2 days prior to mice receiving 18F-FES for PET imaging to avoid competitive binding with ERα. Upon 18F-FES administration via the lateral tail vein, PET/MRI was performed for 15 min at 1 h to 1.5 h post-injection. 18F-FES uptake was not observed in ERα-negative, MDA-MB-231 tumor-bearing mice. 18F-FES uptake was most pronounced in mice harboring MCF-7 tumors in the shoulder. In MCF-7 tumors grown in the inguinal mammary fat pad, 18F-FES uptake was less visible, as the intestinal excretion pattern of 18F-FES obscured the radioactivity detectable in these tumors. To use 18F-FES PET as a tool to visualize ERα expression in ERα-positive breast xenografts, we demonstrate that the visibility of 18F-FES uptake is clear in tumors located away from the abdominal region of mice, such as in the shoulder.
期刊介绍:
JoVE, the Journal of Visualized Experiments, is the world''s first peer reviewed scientific video journal. Established in 2006, JoVE is devoted to publishing scientific research in a visual format to help researchers overcome two of the biggest challenges facing the scientific research community today; poor reproducibility and the time and labor intensive nature of learning new experimental techniques.