PANC-1 xenograft model
Pancreatic cancer is the fourth leading cause of cancer-related fatalities, comprising nearly 90 percent of all pancreatic malignancies. PANC-1 cells are very well studied and extensively employed as in vitro models for pancreatic ductal adenocarcinoma research. Chondroitin sulfate E (CS-E) is a highly sulfated glycosaminoglycan that promotes tumor invasion and metastasis. Sulfotransferase 15 (CHST15) is a specific enzyme that biosynthesizes CS-E. The presence of CS-E is detected in pancreatic ductal adenocarcinoma (PDAC) cells. A 2015 study by Takakura published in PLoS One, investigated the effects of the CHST15 siRNA on tumor cell proliferation in vitro and growth in vivo, using the PANC-1 subcutaneous xenograft model. According to the article, CHST15 siRNA significantly inhibits the expression of CHST15 mRNA in PANC-1 cells in vitro. These findings report that one intratumoral injection of CHST15 siRNA almost completely blocks tumor growth in the PANC-1 subcutaneous xenograft model and could be a novel therapeutic option for PDAC patients. The PANC-1 cell line (human pancreas) is used to create the CDX (Cell Line Derived Xenograft) PANC-1 xenograft mouse model. The PANC-1 xenograft model is a preclinical model enabling studies on tumor growth inhibition such as LIM kinases (LIMK) inhibitors (e.g. T56-LIMKi), or monotherapies (e.g. cisplatin, gemcitabine) in combination with recombinant vaccines (e.g. GLV-1h68).
Download Altogen Labs PANC1 Xenograft Model PowerPoint Presentation:
Basic study design
- To ensure high tumor take in mice, all cells are grown at exponential growth rates. The PANC-1 cells are collected via trypsin-EDTA, and viability is determined by trypan blue exclusion. At this piont, the concentration of the cell suspension is adjusted to the required density for injection.
- One million cells (containing matrigel plus PANC-1 cells in a vol = 100 uL) is injected subcutaneously into 10-12 week old athymic BALB/C nude mice.
- There is continual injection site monitoring to determine tumor establishment. Tumors are calipered and the in-life portion of the study begins with tumor sizes 50-150 mm3.
- Treatment cohorts are injected with test compounds according to the treatment dosing schedule. Pre-dose and post-dose tumor measurements are recorded, along with mouse body weights.
- After final dose, the mice are humanely euthanized and tissues are excised for further analysis. Tumor tissue is removed and weighed. All other tissues of interest are snap frozen, immersed in RNAlater or placed in 10% NBF for histology.
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 PANC-1 xenograft model:
- PANC-1 Tumor Growth Delay (TGD; latency)
- PANC-1 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)
- PANC-1 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