Abstract 105: Establishment of imaging-based orthotopic tumor models for pharmacological evaluation of anticancer agents

Abstract

Abstract Since its emergence in the mid 90's, the in vivo bioluminescent imaging (BLI) technology has been widely accepted by academia and pharmaceutical industry for research and pre-clinical drug development. The non-invasiveness and high sensitivity nature of BLI enables tumor lesions to be detectable far before they are palpable, allowing longitudinal tracking of tumors from their early development stages. BLI is particularly advantageous for monitoring systemic and orthotopic tumors that are not accessible by caliper measurement. Current preclinical evaluation of anti-cancer agents relies heavily on subcutaneous xenograft models. However, ectopically developed tumors in the subcutaneous tissue differ drastically in tumor stromata in aspects of cell contents and drug permeability, thus will often poorly predict pharmacological efficacy of the test agents. The notion that orthotopic models can better recapitulate the clinical tumor development and metastasis, thus better predict the clinical outcome of the anticancer drugs has gradually gained acceptance. Towards the development of better mouse models for pre-clinical drug development, we have established over twenty imaging based orthotopic tumor cell lines, including U87MG and AM38 brain tumors, HCT116, LoVo and SW620 colorectal cancers, A549 lung cancer, MSTO-211H mesothelioma, Raji and Namalwa lymphoma, MiaPaca-3 and Panc-1 pancreatic cancer, HepG2 liver cancer, and DU145 prostatic cancer. These tumor cells are extremely bright in luminescence emission, ranging from 1085 to 6397 photons/second/cell, thus allowing very sensitive detection in orthotopic tissues even with a few hundred cells. The tumorigenicity of the luciferase labeled cells has been validated in the pertinent orthotopic models. Evaluation of the responsiveness of some of the models to standard therapeutic agents has been conducted. In the U87MG orthotopic glioma model, we observed tumor regression in mice treated with temozolomide in a 5 mg/kg, po, q2d x 5 regimen. Current study of the orthotopic MSTO-211H mesothelioma model in response to standard clinical treatment drugs, such as pemetrexed, carboplatin and paclitaxel is in progress. It is expected that these imaging based orthotopic models will improve the pre-clinical pharmacological evaluation of anti-cancer agents and therefore better bridge the preclinical to clinical translation. Citation Format: Ning Zhang, Wei Wang, Dan Meng, Jinjin Pan, Jing Jin, Yanxia Fan, Wenhao Jin, Shuo Zhang, Ze Chen, Xueqin Yang, Hongjun Wang. Establishment of imaging-based orthotopic tumor models for pharmacological evaluation of anticancer agents. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 105. doi:10.1158/1538-7445.AM2014-105