Cancer-Testis Antigens: Immunotherapy Targets for Merkel Cell Carcinoma?
Posted: Monday, October 28, 2019
According to research published in the Journal of Cutaneous Pathology, immune-privileged cancer-testis (CT) antigens may be candidates for targeted immunotherapy in patients with metastatic Merkel cell carcinoma. Bahar Dasgeb, MD, of Thomas Jefferson University, and colleagues noted that “further studies are warranted to explore the utility of these markers in future in vivo application.”
The study evaluated three CT antigens—sperm protein-17 (SP-17), insulin-like growth factor-II mRNA-binding protein 3 (IMP-3), and transmembrane protein with EGF-like and two follistatin-like domains 1 (TMEFF1)—found by transcriptome profiling to be expressed in Merkel cell tumors. The investigators stained the antibodies produced to target these CT antigens. A total of 14 Merkel cell carcinoma skin tissue samples and 12 control skin tissue samples were included.
Overall, SP-17 was the least sensitive, with just 2.06% of tumor cells staining positive. However, of the 14 Merkel cell carcinoma samples, 12 (86%) experienced clear, specific staining of the nucleus for SP-17. All Merkel cell carcinoma samples showed clear staining around the nucleus area for IMP-3, which was more specific, with 52.93% of tumor cells staining positive. Finally, general staining around the nucleus area was noted for TMEFF1 in all Merkel cell carcinoma cases, and a total of 96.51% of tumor cells stained positive, making TMEFF1 the most sensitive though least specific antigen studied.
Disclosure: For disclosures of study authors, visit onlinelibrary.wiley.com.