AACR 2025 Posters: Sneak Peek

From April 25 to 30, 2025, the annual meeting of the American Association for Cancer Research (AACR), one of the largest and longest-standing cancer research conferences in the world, will be held in Chicago. At this year’s AACR meeting, WuXi Biology has been selected to present several posters detailing latest scientific insights, covering a range of cutting-edge topics from preclinical tumor model development and biomarker discovery to the evaluation of novel anti-cancer therapies.

Explore this quick overview of WuXi Biology’s pioneering contributions to be featured at AACR 2025.

Immunology

Poster #936 HPV-related cancer model development and its application in the efficacy evaluation of a saRNA cancer vaccine

Highlights: Cancer remains one of the major diseases threatening human health, with approximately 10% of cases associated with viral infections such as HPV and HBV. These viruses induce cellular carcinogenesis by regulating host cell proliferation, metabolism, and immune mechanisms. In this study, we established an HPV18 E6/E7 overexpression cell line (LLC1-HPV18), which stably expresses oncogenes in vitro and in vivo and induces tumor formation in mice. To further explore the potential of this model in evaluating anti-tumor drugs targeting HPV18, the team designed a self-amplifying RNA (saRNA) vaccine expressing HPV18 E6 and E7. After two immunizations, the saRNA vaccine successfully induced E6/E7-specific IFN-γ⁺ T cell responses and significantly inhibited tumor progression in the LLC1-HPV18 tumor model, improving mouse survival rates. This provides a novel approach for the treatment of HPV18-related cancers.

Session Date and Time: April 27, 2025, 2:00 PM – 5:00 PM

Location: Immunology, Poster section 39, Poster board 5

Tumor Biology

Poster #1270 An Isogeneic Trop-2 expression heterogeneity model for evaluating the bystander killing effect of anti-Trop-2 ADC

Highlights: In recent years, antibody-drug conjugates (ADCs) have made significant strides in cancer treatment, particularly for solid tumors. Among these advancements, the bystander effect, where the cytotoxic payload released by ADCs diffuses to kill nearby tumor cells, plays a crucial role in tumors with heterogeneous antigen expression. To evaluate this effect, this study established a heterogeneous model of Trop-2 antigen expression. In the Trop-2-positive NCI-H292 cell line, Trop-2 was knocked out, and clones with proliferation rates similar to the parental cells were selected. Additionally, Trop-2-negative cells were labeled with luciferase and mCherry. In vitro experiments involved mixing Trop-2-negative and positive cells in varying ratios and treating them with anti-Trop-2 ADC. The bystander effect was assessed using flow cytometry and bioluminescence measurements. In vivo experiments involved subcutaneously implanting a mixture of the two cell types into mice, followed by intravenous administration of the ADC. Tumor volume and bioluminescence were measured, revealing that the anti-Trop-2 ADC exhibited significant bystander killing activity, effectively inhibiting the growth of Trop-2-negative cells. This model provides a robust platform for evaluating the pharmacological efficacy of anti-Trop-2 ADCs.

Session Date and Time: April 28, 2025, 9:00 AM – 12:00 PM

Location: Tumor Biology, Poster section 3, Poster board 3

Clinical Research

Poster #5917 A novel ROR1 antibody with high specificity and sensitivity for predictive biomarker detection in various tumor types

Highlights: ROR1, an orphan receptor resembling a tyrosine kinase, is selectively overexpressed in solid tumors and hematological malignancies but not in normal human tissues, making it a highly promising target for cancer therapy. However, existing detection tools are unable to efficiently detect ROR1 in patient tumor samples through immunohistochemistry. To address this challenge, this study developed a recombinant rabbit monoclonal antibody that demonstrates higher sensitivity and specificity compared to currently available commercial antibodies across multiple detection methods. Additionally, an extensive epidemiological survey was conducted, revealing varying detection rates in cancers such as pancreatic cancer, ovarian cancer, lung adenocarcinoma, endometrial cancer, triple-negative breast cancer, mesothelioma, and esophageal squamous cell carcinoma. This discovery provides a potentially reliable tool for clinical biomarker detection in various tumors with the promise to accelerate the development of ROR1-targeted therapies.

Session Date and Time: April 29, 2025, 2:00 PM – 5:00 PM

Location: Clinical Research, Poster section 32, Poster board 9

Poster #5828 Development of NK humanized mice models for the in vivo evaluation of NK cell-based therapeutics

Highlights: We isolated and expanded human natural killer (NK) cells from peripheral blood mononuclear cells (PBMCs) and transplanted them into human IL-15 transgenic NOG mice, thereby reconstructing a humanized mouse model with functional and persistent human NK cells. The dynamics and phenotype of NK cells were monitored using flow cytometry, and the efficacy of an anti-CD20 antibody was evaluated using an SU-DHL-2 subcutaneous xenograft model. The results showed that anti-CD20 antibody treatment was ineffective in non-humanized mice but significantly inhibited tumor growth in NK cell-humanized mice through antibody-dependent cellular cytotoxicity (ADCC) mediated by human NK cells. This study also examined the infiltration of NK cells into tumors and the expression of activation markers, demonstrating that the model could maintain functional human NK cells for weeks to months. This model provides a valuable preclinical platform for evaluating NK cell-based therapies and holds promise for accelerating the development of novel NK cell-based immunotherapies.

Session Date and Time: April 29, 2025, 2:00 PM – 5:00 PM

Location: Clinical Research, Poster section 29, Poster board 4