title: Ultrasound contrast-enhanced study as an imaging biomarker for anti-cancer drug treatment: preliminary study with paclitaxel in a xenograft mouse tumor model (secondary publication).
abstract: OBJECTIVE
  The purpose of this study was to assess tumor angiogenesis using contrast-enhanced ultrasonography (CEUS) of human prostate cancer cells (PC3) that were implanted in mice before and after paclitaxel injection.
  
  
  METHODS
  Twelve mice were injected with human PC3. The mice were grouped into two groups; one was the paclitaxel-treated group (n=6) and the other was the control group (n=6). Before administering paclitaxel into the peritoneal cavity, baseline CEUS was performed after the administration of 500 μL (1×108 microbubbles) of contrast agent. The area under the curve (AUC) up to 50 seconds after injection was derived from the time-intensity curves. After injection of paclitaxel or saline, CEUS studies were performed at the 1-week follow-up. Changes in tumor volume and the AUC in both two groups were evaluated. After CEUS, the microvessel density (MVD) was compared between the groups.
  
  
  RESULTS
  In the paclitaxel-treated group, the AUC from CEUS showed a significant decrease 1-week after paclitaxel administration (P=0.030), even though the tumor volume showed no significant changes (P=0.116). In the control group, there was no significant decrease of the AUC (P=0.173). Pathologically, there was a significant difference in MVD between both groups (P=0.002).
  
  
  CONCLUSIONS
  The AUC from the time intensity curve derived from CEUS showed an early change in response to the anti-cancer drug treatment that preceded the change in tumor size. The findings of CEUS could serve as an imaging biomarker for assessing tumor responses to anti-cancer drug treatment.
authors.affiliation: Department of Radiology, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Hak Jong
authors.identifier: 0000-0003-0858-7873
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Sung Il
authors.identifier: 0000-0001-7516-5369
authors.initials: SI
authors.lastname: Hwang
authors.affiliation: Department of Molecular Biology, Dankook University, Cheonan, Korea.
authors.forename: Jonghoe
authors.initials: J
authors.lastname: Byun
authors.affiliation: Department of Molecular Biology, Dankook University, Cheonan, Korea.
authors.forename: Hoon Young
authors.initials: HY
authors.lastname: Kong
authors.affiliation: Department of Radiology, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Hyun Sook
authors.initials: HS
authors.lastname: Jung
authors.affiliation: Department of Radiology, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Mira
authors.initials: M
authors.lastname: Kang
keywords: Angiogenesis; Animal study; Anti-cancer treatment; Contrast agent; Ultrasonography