title: A novel preclinical method to quantitatively evaluate early-stage metastatic events at the murine blood-brain barrier.
abstract: The observation that approximately 15% of women with disseminated breast cancer will develop symptomatic brain metastases combined with treatment guidelines discouraging single-agent chemotherapeutic strategies facilitates the desire for novel strategies aimed at outright brain metastasis prevention. Effective and robust preclinical methods to evaluate early-stage metastatic processes, brain metastases burden, and overall mean survival are lacking. Here, we develop a novel method to quantitate early metastatic events (arresting and extravasation) in addition to traditional end time-point parameters such as tumor burden and survival in an experimental mouse model of brain metastases of breast cancer. Using this method, a reduced number of viable brain-seeking metastatic cells (from 3,331 ± 263 cells/brain to 1,079 ± 495 cells/brain) were arrested in brain one week postinjection after TGFβ knockdown. Treatment with a TGFβ receptor inhibitor, galunisertib, reduced the number of arrested cells in brain to 808 ± 82 cells/brain. Furthermore, we observed a reduction in the percentage of extravasated cells (from 63% to 30%) compared with cells remaining intralumenal when TGFβ is knocked down or inhibited with galunisertib (40%). The observed reduction of extravasated metastatic cells in brain translated to smaller and fewer brain metastases and resulted in prolonged mean survival (from 36 days to 62 days). This method opens up potentially new avenues of metastases prevention research by providing critical data important to early brain metastasis of breast cancer events.
authors.affiliation: Department of Basic Pharmaceutical Sciences, Health Sciences Center, School of Pharmacy, West Virginia University, Morgantown, West Virginia. Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas.
authors.forename: Chris E
authors.initials: CE
authors.lastname: Adkins
authors.affiliation: Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas. Department of Pharmaceutics, School of Pharmacy, Alexandria University, Alexandria, Egypt.
authors.forename: Mohamed I
authors.initials: MI
authors.lastname: Nounou
authors.affiliation: Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas.
authors.forename: Rajendar K
authors.initials: RK
authors.lastname: Mittapalli
authors.affiliation: Department of Basic Pharmaceutical Sciences, Health Sciences Center, School of Pharmacy, West Virginia University, Morgantown, West Virginia. Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas.
authors.forename: Tori B
authors.initials: TB
authors.lastname: Terrell-Hall
authors.affiliation: Department of Basic Pharmaceutical Sciences, Health Sciences Center, School of Pharmacy, West Virginia University, Morgantown, West Virginia. Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas.
authors.forename: Afroz S
authors.initials: AS
authors.lastname: Mohammad
authors.affiliation: Department of Basic Pharmaceutical Sciences, Health Sciences Center, School of Pharmacy, West Virginia University, Morgantown, West Virginia.
authors.forename: Rajaganapathi
authors.initials: R
authors.lastname: Jagannathan
authors.affiliation: Department of Basic Pharmaceutical Sciences, Health Sciences Center, School of Pharmacy, West Virginia University, Morgantown, West Virginia. Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas. prlockman@hsc.wvu.edu.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Lockman
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000556:secondary*; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008325:Mammary Neoplasms, Experimental / Q000473:pathology*; D051379:Mice; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D009362:Neoplasm Metastasis; D011720:Pyrazoles / Q000627:therapeutic use; D011804:Quinolines / Q000627:therapeutic use; D015398:Signal Transduction; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D011720:Pyrazoles; D011804:Quinolines; D016212:Transforming Growth Factor beta; C557799:LY-2157299