New Molecular Imaging Agent Accurately Identifies Crucial Cancer Biomarker

The trophoblast cell surface antigen 2 (Trop2) is gaining attention as a potential biomarker for the development of next-generation diagnostic and therapeutic agents for solid tumors, offering promise for revolutionizing cancer treatment. Trop2 is frequently found in various cancers, including triple-negative breast cancer, colorectal cancer, gastric carcinoma, pancreatic cancer, and non-small cell lung cancer. Researchers have recently focused on Trop2 due to its significant involvement in processes such as cell self-renewal, proliferation, transformation, and organ development. Despite its promise, visualizing Trop2 expression effectively and identifying patients who could benefit from Trop2-targeted therapies remains a significant challenge. Now, a new molecular imaging agent can accurately detect Trop2, providing critical information for diagnosis, creating personalized treatment plans, and assessing therapeutic response.

While advancing their understanding of Trop2, researchers at Jiao Tong University (Shanghai, China) developed two novel Trop2-targeted radiotracers: 18F-AlF-RESCA-T4 and 18F-AlF-RESCA-RT4. They conducted preclinical imaging and blocking studies on tumor-bearing mice to evaluate the safety and efficacy of these radiotracers. Additionally, a pilot clinical trial was performed involving three patients suspected of having lung cancer. This trial included a direct comparison of PET/CT imaging using 18F-AlF-RESCA-T4, 18F-AlF-RESCA-RT4, and an earlier developed radiotracer, 68Ga-NOTA-T4.

Image: [18F]AlF-RESCA-T4 immuno-PET/CT imaging of patient with primary lung cancer (Photo courtesy of Jiao Tong University)

Both 18F-AlF-RESCA-T4 and 18F-AlF-RESCA-RT4 showed significant tumor uptake, with 18F-AlF-RESCA-RT4 displaying notably reduced kidney accumulation. In the head-to-head clinical trial comparison, 18F-AlF-RESCA-T4 proved to be the most effective. Initial results from 18F-AlF-RESCA-T4 immuno-PET/CT imaging demonstrated its ability to visualize Trop2 expression in patients suspected of having lung cancer and distinguish lung inflammation, such as tuberculosis, from cancer.

“PET imaging with 18F-AlF-RESCA-T4 will allow physicians to identify patients with Trop2-positive tumors so they can receive Trop2-targeted treatments,” said Weijun Wei, MD, PhD, from Shanghai Jiao Tong University. “This is the cornerstone of precision medicine: selecting the right treatment for the right patient.”