Preclinical CRO offering Xenograft Studies

Services Provided and Model Protocol

In Vivo Contract Research Services (Xenograft, PDX)

Altogen Labs, pre-clinical contract research organization (CRO) provides PDX models, patient chemosensitivity xenograft testing (PCX), as well as over 50 validated in vivo xenograft models for efficacy studies on drugs, oncologic treatments and laboratory research including pharmacokinetic and toxicology studies (ADME, PK/PD, IC50, LD50, and many more). These models can be used for drug discovery, cancer studies and treatment improvement, as well as numerous oncology research applications. Xenograft immunocompromised mice based models provide adequate test models for different types of human cancer, diabetes, wound healing and other conditions.

The patient-derived human tumor xenografts (PDX) are explants directly injected to the xenograft model and not propagated in vitro. Altogen Labs provides validated hystotypes for both preclinical and clinical research applications, however there are certain advantages and disadvantages of PDX xenograft models:

The mouse xenograft models are widely used for cancer therapy research due to following advantages:

  • They can be used for personalized therapy research, and the results are obtained relatively fast
  • The human tumor stroma can be included in the xenograft
  • The researcher studies human tumor response in vivo (in vitro results are known to translate poorly)
  • The same tumor can be used for testing different drugs or concentrations
  • Orthotopic xenografts can be obtained and studied
  • “Humanized” mice can be used
  • These observations make the mouse xenograft models a very useful tool, which can be manipulated to simulate the original tumor response

The techniques also have some disadvantages:

  • Although very useful, orthotopic xenografts are known to be very expensive
  • The SCID or athymic nude mice (immunocompromised) are not capable of exhibiting an immune response

Altogen Labs offers services for the establishment and expansion of Patient Derived tumor Xenografts (PDX). Our basic PDX service includes:

  • Prepare and implant patient-derived-tumor samples in female athymic nude mice
  • Grow and monitor tumors to maximum size allowed in protocol (1000-1500 mm3); this is termed the F0 tumor generation
  • Excise F0 tumors and process for storage and implantation for expansion to generate F1 tumors
  • Excise F1 tumors and process for storage and implantation for expansion to generate established F2 and subsequent tumor generations (F3…Fn)
  • Implantation of established tumor generations will be of use for treatment studies as outlined in the basic xenograft study design

Possible murine models for xenotransplantation include:

  • 6- to 7-week-old female BALB/c athymic (nude) mice
  • 9-11 week old NOD/SCID immunocompromised mice
  • the mouse line of the client’s choice (other mouse lines are described here)

Xenografting is typically accomplished by subcutaneous (s.c.)  injection of one million cells per animal from the selected tumor cell line. Xenotransplantation in other areas may be possible upon consultation with Altogen Labs. We offer assistance in choosing the best model suitable for the client’s goals. In addition, there are tools available to search for specific models.

Some study objectives may be to identify therapies that target specific carcinogenesis pathways that are dysregulated in tumor cells. In this case, tumor cell lines with known genetic mutations will be used to demonstrate pathway dependent therapy. Altogen Labs will aid the client in choosing the most useful cell line(s) from the myriad of choices.

Clients choose a tumorigenic cell line of interest, an animal model and select the desired number and size of experimental groups. Following acclimation to the vivarium environment, the chosen mice are sorted according to body mass. The selected cancer cell lines are prepared in matrigel and grafted subcutaneously into the flank area (or elsewhere as per the client’s instruction). The animals are examined daily for tumor appearance and clinical signs. When tumors are established, animals are sorted based on tumor volume.

Cell Engraftment Options

Alternative cell engraftment sites will be used if required. Common alternative sites include:

  • Injection into the mammary fat pad (breast cancer models)
  • Intraperitoneal injection (ovarian cancer models)
  • Orthotopic transplantation in the prostate
  • Tail vein injection and left ventricular injection for metastasis studies

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.

Treatment Options

Most treatment options required by the client can be accommodated. We also offer services to quickly determine the optimal route of administration and treatment schedule for your test compound.

Options for administration of the compound of interest include:

  • Dosing route: intratumoral, oral (gavage or via dietary admixture), topical, intramuscular, subcutaneous, intranasal, intravenous, intratracheal, via continous infusion, implantation of slow release pellets, implantation of osmotic pumps or intraperitoneal
  • Dosing frequency
  • Duration of dose administration
  • We also offer the possibility of a 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

All studies performed by Altogen Labs include daily cage-side observations by experienced scientists.  Whole body weight and tumor volumes are measured every two days. A detailed model protocol for xenograft studies can be found here.

Animal Disease Model Optimization

We strongly support the use of the most suitable animal models for scientific inquiry. The information gained from this investigation is used to create life-saving drugs and regimens for various diseases and conditions. Our xenograft CRO facility has the capacity to hold up to 1000 mice at a time. These mice are routinely examined for tumor growth delay (TGD, latency), tumor growth inhibition (TGI), toxicity and rates of survival. Previously, our xenograft research has been used to determine lead compounds, modify dose schedules and ascertain combination strategies. Our team also has the necessary skills to assist you in understanding the molecular mechanics of drug action using our in vivo models.

Experimental Methods

Our in vivo xenograft CRO services include the whole gamut of research assistance including the following:

  • Biospecimen collection
  • Caliper measurements
  • Mouse model induction
  • Xenograft and orthotopic transplantation

Our repertoire also includes the following support services:

  • Blood and urine glucose
  • Clinical chemistry
  • Histological services
  • Lipid distribution
  • Metabolic assays
  • Access to specialized imaging: MRI, micro-CT, PET

Alternative Protocols

Our in vivo xenograft CRO Services are entirely customizable. Our well-equipped premises and expert staff can help you by:

  • Providing in-house or accommodating customer-provided cell lines
  • Providing staged or un-staged testing facility
  • Assigning mice to groups at random or classifying them by weight, tumor size or any other parameters of your choice
  • Administering test compounds by a number of methods, as mentioned previously
  • Providing quick-freeze facilities for collected tumors
  • Fixing collected tumors for histology or any other specific assays
  • We also have in-house facilities to analyze blood chemistry at any time during the study

Results and Analysis

No matter how long your study or how intricate its requirements are, you can depend on us for a complete analysis of the data. We will present you with the results and summary along with all of the following and other information at your request:

  • Tumor cell kill rate
  • Tumor growth inhibition (TGI)
  • Tumor growth delay (TGD)
  • Increased life span (ILS)
  • Estimated tumor volume
  • Survival time to specified tumor volume
  • Tumor doubling time