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Kirsten rat sarcoma (KRAS) is a frequently mutated oncogene responsible for several oncogenic KRAS variants and for driving tumor proliferation. Some nonsmall cell lung cancer (NSCLC) tumors exhibit KRAS G12C mutations, which can be targeted for inhibition using covalent and more recently noncovalent inhibitors. Sotorasib was the first FDA-approved G12C inhibitor that has shown efficacy in lung cancer patients, but with mixed responses. The lack of efficacy can be attributed to tumor heterogeneity (lack of G12C mutations) and/or inefficient delivery. Targeted KRAS G12C imaging has potential to identify NSCLC lesions with the targeted mutation and elucidate the oncogene's role in driving tumor growth and correlating responses to treatment. Toward this goal, we have developed a sotorasib-based molecular agent for PET imaging and tested its efficacy in targeting tumor lesions with KRAS G12C mutations. Here, we describe the synthesis, in vitro and in vivo evaluation of an [ 124 I]I-Sotorasib analog in targeting G12C mutant tumor lesions using PET imaging., Competing Interests: The authors declare the following competing financial interest(s): NVKP is a paid consultant for Jubillant Draximage and Evergreen Theragnostics and a shareholder. All other authors have no conflict to declare., (© 2024 American Chemical Society.)

We report an innovative approach to producing bacteriochlorins (bacs) via formal cycloaddition by subjecting a porphyrin to a trimolecular reaction. Bacs are near-infrared probes with the intrinsic ability to serve in multimodal imaging. However, despite their ability to fluoresce and chelate metal ions, existing bacs have thus offered limited ability to label biomolecules for target specificity or have lacked chemical purity, limiting their use in bio-imaging. In this work, bacs allowed a precise and controlled appending of clickable linkers, lending the porphyrinoids substantially more chemical stability, clickability, and solubility, rendering them more suitable for preclinical investigation. Our bac probes enable the targeted use of biomolecules in fluorescence imaging and Cerenkov luminescence for guided intraoperative imaging. Bacs' capacity for chelation provides opportunities for use in non-invasive positron emission tomography/computed tomography. Herein, we report the labeling of bacs with Hs1a, a (NaV1.7)-sodium-channel-binding peptide derived from the Chinese tarantula Cyriopagopus schmidti to yield Bac-Hs1a and radiolabeled Hs1a, which shuttles our bac sensor(s) to mouse nerves. In vivo, the bac sensor allowed us to observe high signal-to-background ratios in the nerves of animals injected with fluorescent Bac-Hs1a and radiolabeled Hs1a in all imaging modes. This study demonstrates that Bac-Hs1a and [ 64 Cu]Cu-Bac-Hs1a accumulate in peripheral nerves, providing contrast and utility in the preclinical space. For the chemistry and bio-imaging fields, this study represents an exciting starting point for the modular manipulation of bacs, their development and use as probes for diagnosis, and their deployment as formidable multiplex nerve-imaging agents for use in routine imaging experiments.