Abstract 1864: New generation of fully human anti-progranulin monoclonal antibodies inhibiting migration and tumor formation of non-small cell carcinoma cells
Authors: Serrero Ginette , Dong Jianping , Yue Binbin , Oshimura Mitsuo , Dong Chun , Hayashi Jun 
Published: March 2024

Abstract
Advanced carcinomas of the lung or the breast are characterized by invasiveness and poor survival. Identifying novel targeted therapies to potentiate standard of care (SOC) therapy, remains an unmet need. In the past 4 years, numerous targeted therapies in Oncology have been approved by the Food and Drug Administration (FDA). However, the identification of targeted therapies against direct tumor biological drivers remains important. Progranulin (PGRN/GP88) is a biological driver of tumorigenesis, survival, and drug resistance in multiple cancers including breast and lung cancers. PGRN/GP88 tissue expression is an independent prognostic factor of recurrence and mortality while elevated serum PGRN/GP88 level is associated with poor outcomes such as progression of disease and shortened survival. The importance of inhibiting PGRN/GP88 expression or action effect on the proliferation and tumor growth of several cancers has been established by several laboratories including ours. In the current study, in association with Precision Antibody, we developed anti-PGRN/GP88 fully human monoclonal antibodies by immunizing TC transgenic humanized mice with recombinant human progranulin. Within 60 days following the start of immunization, several fully human anti-progranulin monoclonal antibodies were developed, characterized by several functional assays including neutralization, inhibition of PGRN/GP88 cell surface binding, proliferation, migration in vitro and tumor formation in vivo. Results: The inhibition of PGRN/GP88 action by fully human monoclonal antibodies inhibited cell proliferation and migration in a dose-and time-dependent fashion. Octet analysis determined Kd in the range of 10−11 M to 10−10 M. Transwell assay showed that anti-PGRN treatment inhibited migration of non-small cell lung cancer cells such as H1299 and A549 cells. In vivo xenograft studies with H1299 cells injected in athymic nude mice showed that fully human anti-PGRN antibodies inhibited tumor growth when compared to antibody control treated mice. Conclusion: PGRN/GP88 represents a therapeutic target for non-small cell carcinoma with two companion diagnostics (tissue test and ELISA to measure GP88 circulating levels). The use of the TC transgenic mice allows for the rapid development of fully human high affinity monoclonal antibodies bypassing the need for chimerization or humanization and affinity maturation of monoclonal antibodies raised in mice or other humanized systems. This work is supported by SBIR grants R44 CA 224718 and R44CA162729 from the National Cancer Institute to GS.
Citation Format: Ginette Serrero, Jianping Dong, Binbin Yue, Mitsuo Oshimura, Chun Dong, Jun Hayashi. New generation of fully human anti-progranulin monoclonal antibodies inhibiting migration and tumor formation of non-small cell carcinoma cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1864.