Colon 26 Syngeneic Model Service for Colon Cancer

The Colon 26 syngeneic model service for colon cancer is an immune-competent murine platform in which the NMU-induced, Kras-mutant Colon 26 colon adenocarcinoma is engrafted into syngeneic BALB/c mice, delivering exceptionally fast tumor growth with robust metastatic competence for chemotherapy, targeted-therapy, and immunotherapy evaluation. Alfa Cytology provides this model as a complete preclinical capability — covering authenticated Colon 26 / Colon26-Luc expansion and banking, standardized subcutaneous, cecal-orthotopic, or lung-metastatic implantation, scheduled tumor-growth and in vivo imaging monitoring, and full histopathology with immune-context endpoints — all configured around each sponsor’s regimen, schedule, and decision timeline.

Overview of Colon 26 Syngeneic Model for Colon Cancer

Colon 26 is a bona fide classic of cancer pharmacology — one of the transplantable colon tumor lines created at the Southern Research Institute by Corbett and colleagues in 1975 through a single rectal application of the alkylating carcinogen N-nitroso-N-methylurethane (NMU) to a female BALB/c mouse, and the in vitro culture was established from solid tumor tissue in 1988. It is a grade IV, undifferentiated colon adenocarcinoma that grows with startling speed: doubling times of 15–20 hours in vitro translate into flank tumors of roughly 11 mm within nine days of implanting as few as 1 × 10⁵ cells in vivo. Modern genomics has given the line a precise molecular identity: it carries an activating Kras mutation, a homozygous deletion of the Cdkn2a tumor suppressor locus, and a complex aneuploid genome with triploid and tetraploid regions; cells are female in origin and present MHC class I (H-2D^d, H-2K^d, H-2L^d) while lacking MHC class II and its transactivator Ciita — a caveat that informs how immunotherapy results are interpreted. The viral envelope glycoprotein gp70 serves as its model tumor antigen.

Fig 1. Anti-PD-1 screening across 23 syngeneic models and comparative efficacy in CT-26 versus Colon 26 syngeneic models — Colon 26 tumors are insensitive to anti-PD-1 (p = n.s.) but responsive to anti-CTLA-4 (p < 0.0001) in BALB/c mice bearing subcutaneous Colon 26 tumors. (Sato, Yosuke, et al., 2021)

As a syngeneic system, Colon 26 played a historic role in drug development — it was among the models that established the preclinical activity of irinotecan — and it remains one of the most heavily used colon carcinoma platforms, appearing in hundreds of published studies. Its versatility is unusual: subcutaneous flank grafts for rapid efficacy screens; cecal-wall orthotopic implantation of luciferase-tagged cells (CT26-luc1), suspended in Matrigel, which gives consistent take with in vivo bioluminescent tracking of total tumor burden and lymph node spread; and intravenous inoculation at reduced cell numbers (about 5 × 10⁵ cells in 50–100 μL) that seeds a lung-metastasis model in which 5-fluorouracil demonstrably suppresses metastatic signal. The line responds to standard agents — 5-FU, oxaliplatin, irinotecan — and has been the substrate for modern combination immunology, including semaphorin-4D blockade with anti-CTLA-4 and anti-PD-1, and hyperthermia-plus-chemokine-derivative regimens that dramatically reduce lung metastatic burden. The banked luciferase derivative Colon26-Luc, created by pMSCV-luc transduction with puromycin selection, enables quantitative imaging across all three implantation formats.

Cell Line Information: Colon 26

The table below consolidates the key biological, cultural, and modeling characteristics of the Colon 26 line and its luciferase-labeled derivative Colon26-Luc.

Our Services

Few syngeneic colon models compress the path from implantation to decision the way this one does, and Alfa Cytology runs the Colon 26 program to exploit that speed responsibly: authenticated Colon 26 / Colon26-Luc banks, all three validated implantation formats, disciplined caliper and imaging schedules, and endpoint pathology that accounts for the line’s MHC class II-negative biology — all under one accountable preclinical operation.

Workflow of Colon 26 Syngeneic Model Construction

Construction follows the published methodologies for each implantation format: Colon 26 or Colon26-Luc cells are expanded under authenticated conditions, formulated as a standardized suspension, implanted subcutaneously, into the cecal wall, or intravenously into BALB/c mice, and followed by growth and imaging monitoring with histopathological endpoint analysis. The workflow comprises the following stages.

1. Cell authentication and banking: Colon 26 or Colon26-Luc cells are STR/identity-verified, confirmed mycoplasma-negative, and expanded into low-passage working banks under standardized RPMI-1640 culture conditions.
2. Cell harvest and formulation: Healthy cultures are harvested, counted and viability-checked, then resuspended per format: approximately 1 × 10⁵ cells in 100 μL PBS for flank grafts, a Matrigel-supported suspension for cecal-wall implantation, or 5 × 10⁵ cells in 50–100 μL for the lung-metastatic model.
3. Anesthesia and implantation: BALB/c mice are anesthetized with isoflurane; cells are implanted subcutaneously into the flank, submucosally into the exteriorized cecal wall, or injected intravenously, per the study arm.
4. Establishment monitoring: Tumors are monitored by caliper (flank/cecum) or by in vivo bioluminescence after luciferin administration (luciferase arms); engraftment, latency, and baseline burden are recorded before randomization.
5. Treatment administration: Experimental arms — 5-FU, oxaliplatin, irinotecan and combinations; checkpoint inhibitors and myeloid-targeting agents; hyperthermia or locoregional modalities — proceed per study design with body-weight and toxicity monitoring.
6. Imaging and interim measurements: Caliper measurements or serial bioluminescence sessions track tumor growth kinetics; lung-metastatic arms are imaged weekly to quantify thoracic signal over time.
7. Endpoint and histopathological analysis: Endpoints integrate tumor-growth curves, survival, and final tumor weight with ex vivo organ bioluminescence for metastatic mapping and histopathology (H&E with Ki67, CD8, and marker-specific immunohistochemistry), with immune-context flow cytometry where the design requires it.

Fig 2. Colon 26 Syngeneic Model construction workflow.

Case Study-Colon 26 Syngeneic Model Development

Alfa Cytology has conducted preclinical programs on the Colon 26 platform spanning chemotherapy benchmarking, immunotherapy combination evaluation, and anti-metastatic screening across flank, cecal-orthotopic, and lung-metastatic formats. In these studies, engrafted Colon 26 tumors were monitored through scheduled caliper and imaging measurements, treated per randomized regimens, and characterized at endpoint by histopathology and metastatic mapping. Study-level datasets are available upon request.

Why Choose Alfa Cytology?

Alfa Cytology pairs classical-model operational experience with quantitative imaging and immune-aware endpoint design, so every Colon 26 study is executed with the speed, consistency, and interpretive rigor this heavily benchmarked line demands.

• Focused experience with Colon 26/CT26 across all three validated implantation formats, including cecal-orthotopic and lung-metastatic workflows.
• A single coordinated team managing cell banking, implantation surgery, in vivo imaging, and endpoint pathology under one quality framework.
• Design awareness of the line’s MHC class II-negative biology, informing immunotherapy arm interpretation from the outset.
• Flexible regimens spanning standard chemotherapy, checkpoint and myeloid-targeting combinations, and locoregional modalities.
• Transparent milestone reporting and rapid scientific feedback throughout the engagement.

Contact Us

If your colon cancer program needs a fast, heavily benchmarked syngeneic platform across flank, orthotopic, or metastatic formats, Alfa Cytology is ready to build the study around your regimen. Reach out to us with your study design and timeline, or contact us today for a customized proposal and quotation for the Colon 26 syngeneic model service.

For research use only. Not intended for any clinical use.