Identification of a novel targeting peptide for cervical clear cell adenocarcinoma by in vivo phage display screening combined with immunofluorescent analysis

Background: Cervical clear cell adenocarcinoma (CCAC) is a subtype of cervical adenocarcinoma with distinct biological characteristics. Identification of a novel targeting peptide to advance the development of innovative diagnostic approaches and drug-targeted therapies for CCAC. Methods: In this study, we utilized in vivo phage display, a novel high-throughput screening technology, to identify tumor-targeting peptides for cervical carcinoma. The phage display peptide (Ph.D.-C7C™) library was screened three times, following which phage clones with a strong affinity for cervical cancer HeLa cells were identified. Subsequent phage detection and sequencing revealed the LLRSTGF peptide sequence, denoted as CCSP (cervical cancer specifically targeting peptide), responsible for binding to cervical cancer HeLa cells. CCSP was synthesized with 5-Carboxyfluorescein (5-FAM) fluorescent labeling, and its specificity and affinity were evaluated in both HeLa cells and clinical cervical tissues through immunofluorescent staining. Results: The results demonstrated that CCSP exhibited strong and specific binding to HeLa cells, particularly in the cell membrane and cytoplasm. Furthermore, CCSP displayed significant targeting capability towards CCAC tissues in human cervical cancer specimens, as indicated by intense fluorescent signals localized within the tumor cell membrane and cytoplasm. Conclusions: Our findings establish CCSP as a peptide that specifically interacts with CCAC, indicating that CCSP could hold potential as a targeting carrier for highly effective chemotherapy drugs, warranting further investigation.