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Evaluation of Lung Metastasis in Mouse Mammary Tumor Models by Quantitative Real-time PCR
Published on: January 29, 2016
A novel noninvasive method for evaluating experimental lung metastasis in mice
Arnulfo Mendoza1, Radhika Gharpure, John Dennis
1Tumor and Metastasis Biology Section, Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA.
Journal of the American Association for Laboratory Animal Science : JAALAS
|September 18, 2013
Summary
A new noninvasive test, the Pulmonary Assessment of Advanced Metastasis (PAAM) test, can detect advanced lung metastasis in mice. This simple method aids researchers in longitudinal cancer studies and improves animal welfare.
Area of Science:
- Oncology
- Animal Models
- Cancer Research
Background:
- Metastasis is a major challenge in cancer, necessitating accurate in vivo models for study.
- Longitudinal monitoring of pulmonary metastatic burden in mice is crucial but current methods (imaging, morbidity assessment) have limitations.
- There is a need for inexpensive, reproducible methods to detect advanced metastatic burden before mortality in murine models.
Purpose of the Study:
- To develop and validate a noninvasive technique for assessing pulmonary metastatic burden in laboratory mice.
- To provide a simple, reproducible, and efficient method for detecting advanced pulmonary metastasis.
- To contribute to the humane care of mice during longitudinal cancer studies.
Main Methods:
- Development of the Pulmonary Assessment of Advanced Metastasis (PAAM) test.
- PAAM involves restraining an awake mouse and applying gentle pressure under the xiphoid process to assess respiratory distress.
- Validation across 4 distinct pulmonary metastasis models (n=114 mice) with 3 independent evaluators, confirmed by postmortem histology.
Main Results:
- The PAAM test demonstrated transient respiratory distress signs within 3 seconds in mice with advanced lung metastases.
- The PAAM test achieved 94% positive and negative predictive values across multiple models and evaluators.
- Histologic assessment validated the PAAM test's accuracy in detecting advanced pulmonary metastasis.
Conclusions:
- PAAM is a simple, reproducible, and efficient noninvasive method for detecting advanced pulmonary metastasis in mice.
- This technique aids in the humane monitoring of mice during longitudinal cancer studies.
- PAAM offers a valuable tool for researchers studying cancer metastasis in murine models.
