Calu-3 xenograft model
The Calu-3 cell line (human lung) is used to create the CDX (Cell Line Derived Xenograft) Calu-3 xenograft mouse model. The Calu-3 tumor model is a well established xenograft model to study the effects therapeutics, such as erlotinib, trastuzumab and pertuzumab on HER2 and EGFR expressing cells.
Basic study design
1. Cells are maintained at exponential growth prior to injection.
2. Trypsinized CALU-3 cells are collected and viable cell counts are then determined using a trypan blue exclusion assay (required 98% viability). The collected cell suspension is then adjusted to the appropriate cell density.
3. The mice (athymic nu/nu or BALB/c; 12 w.o.) receive a single subcutaneous injection in the hind leg flank of 100 uL containing one million cells of the matrigel/CALU-3 suspension.
4. All injection sites are palpated up to three times weekly to determine tumor establishment. Tumors are then measured via digital calipers until they reach an average size of 50-150 mm3.
5. Animals are then randomized into predetermined treatment cohorts. Administration of the compound of interest is performed according to the customer supplied treatment schedule.
6. Mouse weights are recorded 3 times weekly and tumors are measured daily.
7. Animals are euthanized when the tumor size reaches 2,000 mm2 or the predetermined tumor size limit.
8. Necropsy and tissue collection are performed as defined for termination of experiment.
9. Tumors are excised, documented by digital imaging and weighed.
10. A standard gross necropsy is performed and the tissues are collected for further downstream analysis.
11. Tumors/tissues are snap frozen in LN2, stabilized in RNAlater, prepared for histological evaluation, or nucleic acid isolated for downstream genetic analysis.
Xenograft animal models are used to assess the effectiveness of drugs against specific types of cancer. New medicines are tested on staged tumor growths that have been engrafted via subcutaneous or orthotopic inoculation in an immunocompromised mouse or rat model. All clinically approved anti-cancer agents have been evaluated with conventional preclinical in vivo models. Xenograft studies can be highly complex, starting with the selection of the appropriate animal model, choice of tumorigenic cell line, administration method, dosing, analysis of tumor growth rates and tumor analysis (histology, mRNA and protein expression levels).
Altogen Labs provides an array of laboratory services using over 30 standard Cell Line Derived Xenograft (CDX) models and over 20 PDX models. Researchers investigating the role of specific proteins or gene products in regulating tumor growth can benefit from development of protein overexpression (genetically engineered to ectopically express proteins, tumor suppressors, or oncogenes) and RNAi cell lines with long term gene silencing. Altogen Labs provides quantitative gene expression analysis of mRNA expression (RT-PCR) and protein expression analysis using the WES system (ProteinSimple).
The dosing of the experimental compound of interest is initiated, for a staged study, when the mean tumor size reaches a specified volume (typically 50-100 mm3). In an unstaged study, the dosing of the compound of interest is initiated immediately after xenografting. Mice are dosed once or twice a day for 28 days (or other desired study duration) via the chosen route of administration. Tumor volume (mm3) is calculated via the “(W x W x L) / 2” formula, where W is tumor width and L is tumor length.
Animal handling and maintenance at the Altogen Labs facility is IACUC-regulated and GLP-compliant. Following acclimatization to the vivarium environment, mice are sorted according to body mass. The animals are examined daily for tumor appearance and clinical signs. We provide detailed experimental procedures, health reports and data (all-inclusive report is provided to the client that includes methods, results, discussion and raw data along with statistical analysis). Additional services available include collection of tissue, histology, isolation of total protein or RNA and analysis of gene expression. Our animal facilities have the flexibility to use specialized food or water systems for inducible gene expression systems.
Following options are available for the Calu-3 xenograft model:
- Calu-3 Tumor Growth Delay (TGD; latency)
- Calu-3 Tumor Growth Inhibition (TGI)
- Dosing frequency and duration of dose administration
- Dosing route (intravenous, intratracheal, continuous infusion, intraperitoneal, intratumoral, oral gavage, topical, intramuscular, subcutaneous, intranasal, using cutting-edge micro-injection techniques and pump-controlled IV injection)
- Calu-3 tumor immunohistochemistry
- Alternative cell engraftment sites (orthotopic transplantation, tail vein injection and left ventricular injection for metastasis studies, injection into the mammary fat pad, intraperitoneal injection)
- Blood chemistry analysis
- Toxicity and survival (optional: performing a broad health observation program)
- Gross necropsies and histopathology
- Positive control group employing cyclophosphamide, at a dosage of 50 mg/kg administered by intramuscular injection to the control group daily for the study duration
- Lipid distribution and metabolic assays
- Imaging studies: Fluorescence-based whole body imaging, MRI