RE: AACR Molecular Cancer Therapeutics Journal28 Dec 2019 04:44
Abstract
Tumor glycans constitute attractive targets for therapeutic antibodies. The sialylated glycocalyx plays a prominent role in cancer progression and immune evasion. Here we describe the characterization of the monoclonal antibody, FG129, which targets tumor-associated sialylated glycan and demonstrate its potential for multimodal cancer therapy. FG129, obtained through BALB/c mouse immunizations with liposomes containing membrane glycan extracts from the colorectal cancer cell line LS180, is a mIgG1?, that targets sialyl-di-Lewisa-containing glycoproteins. FG129, as well as its chimeric human IgG1 variant, CH129, bind with nanomolar functional affinity to a range of colorectal, pancreatic and gastric cancer cell lines. FG129 targets 74% (135/182) of pancreatic, 50% (46/92) of gastric, 36% (100/281) of colorectal, 27% (89/327) of ovarian and 21% (42/201) of non-small cell lung cancers, by immunohistochemistry. In our pancreatic cancer cohort, high FG129 glyco-epitope expression was significantly associated with poor prognosis (p=0.004). Crucially, the glyco-epitope displays limited normal tissue distribution, with FG129 binding weakly to a small percentage of cells within gallbladder, ileum, liver, oesophagus, pancreas, and thyroid tissues. Owing to glyco-epitope internalization, we validated payload delivery by CH129 through monomethyl auristatin E (MMAE) or maytansinoid (DM1 and DM4) conjugation. All three CH129 drug conjugates killed high-binding colorectal and pancreatic cancer cell lines with (sub)nanomolar potency, coinciding with significant in vivo xenograft tumor control by CH129-vcMMAE. CH129, with its restricted normal tissue distribution, avid tumor binding and efficient payload delivery, is a promising candidate for the treatment of sialyl-di-Lewisa expressing solid tumors, as an ADC or as an alternative cancer immunotherapy modality.
Received March 4, 2019.
Revision received October 25, 2019.
Accepted December 9, 2019.
Copyright ©2019, American Association for Cancer Research.
Silvana T Tivadar, Richard S McIntosh, Jia Xin Chua, Robert Moss, Tina Parsons, Abed M. Zaitoun, Srinivasan Madhusudan, Lindy G Durrant and Mireille Vankemmelbek
Morning Guys and Morning Bermuda, if you can Bermuda (and others) translate that as best you can so as we cam all benefit to the maximum of what seems like a very exciting study. Thanks.