ZR-75-1 Xenograft Model Service for Breast Cancer

The ZR-75-1 xenograft model delivers a highly physiological, hormone-responsive in vivo translational platform specifically optimized for validating novel selective estrogen receptor degraders (SERDs), endocrine combination regimens, and targeted therapies against luminal breast cancer. Alfa Cytology offers a comprehensive, end-to-end ZR-75-1 xenograft model service, integrating fully authenticated cellular assets with standardized exogenous hormone supplementation and molecular readouts to accelerate preclinical oncology pipelines.

Overview of ZR-75-1 Xenograft Model for Breast Cancer

The ZR-75-1 cell line is a well-characterized and structurally distinct human mammary carcinoma model widely used in preclinical oncology to investigate luminal subtype breast cancer pathogenesis and therapy-induced resistance cascades. Originally isolated from the peripheral blood or malignant effusion of a 63-year-old Caucasian female patient undergoing treatment for an infiltrating ductal carcinoma, this model is molecularly classified as a luminal B archetype. It is phenotypically driven by a robust co-expression of functional ER and PR, accompanied by normal or low, non-amplified levels of HER2.

When established in vivo as a xenograft in immunocompromised mice, ZR-75-1 cells form solid, differentiated epithelial tumors that accurately mimic the glandular architecture, mucin production, and specific therapeutic vulnerabilities seen in clinical luminal breast malignancies. Because ZR-75-1 is a strictly hormone-dependent platform, successful in vivo engraftment, uniform tumor take rates, and stable growth kinetics require continuous exogenous estrogen support, typically achieved by pre-implanting a slow-release 17β-estradiol pellet subcutaneously into the host animal prior to cell transfer.

Fig 1. ZR-75-1 cells were infected with ATP6AP1 overexpression and ATG5 knockdown lentiviruses and harvested for RT qPCR. (Yan Z, et al., 2025)

Cell Line Information: ZR-75-1

The ZR-75-1 cell line maintains a stable epithelial morphology in vitro and reliably preserves its primary hormone receptor-positive profiling and estrogen-dependent growth traits upon in vivo transplantation.

Our Services

Alfa Cytology provides a fully integrated, turnkey solution for the ZR-75-1 Xenograft Model Service. Our dedication to quality begins with rigorous cell line authentication and mycoplasma testing. We manage every critical step of the preclinical journey—from standardized cell preparation, 17β-estradiol pellet implantation, orthotopic or subcutaneous inoculation, in-life monitoring, to comprehensive endpoint analyses including IHC for ER/PR status and PK/PD profiling. Leveraging our expertise in hormone-dependent luminal breast cancer models, we deliver robust data packages tailored to accelerate your drug discovery programs.

Workflow of ZR-75-1 Xenograft Model Construction

Alfa Cytology executes a standardized and strictly regulated workflow to build and validate the ZR-75-1 xenograft model:

• Cell Culture & Quality Control: ZR-75-1 cells are cultivated in cell-bank-certified growth media under optimized environmental parameters. Quality control verification involves mandatory STR profiling and mycoplasma clearance checks to guarantee phenotypic identity and purity before inoculation.
• Hormone Pellet Implantation: Since ZR-75-1 tumor take rates depend heavily on sustained hormone levels, immunocompromised mice are subcutaneously implanted with a validated, slow-release 17β-estradiol pellet under aseptic conditions prior to cell transfer.
• Precision Inoculation: A calibrated suspension of high-viability ZR-75-1 cells is prepared and blended with a verified biological basement membrane matrix carrier to optimize spatial distribution and support initial survival. The mixture is precisely injected in vivo via orthotopic mammary fat pad or subcutaneous routes.
• Longitudinal Growth Tracking: Following model establishment, tumor growth kinetics are tracked systematically using high-precision digital calipers under continuous health monitoring. Animal weights, general welfare behavior, and pellet retention are routinely recorded.
• Stratification & Dosing: Once the tumors reach a predetermined, statistically optimal volume range, animals are randomized into therapeutic cohorts to balance group parameters perfectly before dosing protocols begin.

Fig 2. ZR-75-1 Xenograft Model Construction Workflow

Case Study - ZR-75-1 Xenograft Model Development

In a recent preclinical trial conducted at Alfa Cytology, the ZR-75-1 xenograft model was successfully utilized to evaluate the therapeutic efficacy and target engagement of a novel small-molecule CDK4/6 inhibitor when combined with a next-generation oral SERD. Under optimized estrogen-supplemented modeling conditions and standardized matrix-assisted inoculation protocols, our technical team achieved highly reproducible tumor engraftment and uniform growth kinetics across all cohorts, enabling an unobstructed and definitive assessment of combination synergy.

Our Advantages

Choosing the right partner for your hormone-receptor-positive luminal breast cancer research is critical for generating high-quality, reproducible data. Alfa Cytology stands out by offering specialized expertise and high-standard preclinical services:

• Model Authenticity: Fully verified human tumor cell lines with stable, traceable genetic hallmarks and confirmed ER+/PR+ expression profiles.
• Technical Consistency: Standardized 17β-estradiol pellet supplementation and optimized inoculation protocols ensuring uniform tumor kinetics and minimized variance.
• Multi-Parametric Endpoints: Capacity for advanced readouts, including digital tumor kinetics, steroid receptor density profiling, and PK/PD tissue processing.
• Regulatory Compliance: Studies executed by a specialized team adhering strictly to international preclinical research and animal welfare standards.

Contact Us

Are you looking to advance your therapeutic pipeline against hormone-receptor-positive luminal breast cancer or evaluate novel endocrine strategies using the robust ZR-75-1 xenograft platform? The expert scientific team at Alfa Cytology is ready to build a customized study design that fulfills your strategic research goals. Please contact us today to speak directly with an oncology specialist and request a project-specific consultation and quotation.

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