A Novel DNA Aptamer Probe Recognizing Castration Resistant Prostate Cancer in vitro and in vivo Based on Cell-SELEX

Abstract

Background

Early recognition of castration-resistant state is of significance for timely adjustment of treatment regimens and improvement of prognosis.

Purpose

This study aims to screen new aptamers CRda8 and CRda21 which recognize castration resistant prostate cancer (CRPC) cells with high affinity and specificity by SELEX technology.

Methods

The enrichment of specific aptamer candidates was monitored by flow cytometric analysis. The affinity and specificity of aptamer candidates were evaluated by flow cytometry and immunofluorescence assay. MR imaging of CRda21-conjugated polyethylene glycol (PEG)-Fe₃O₄ nanoparticles to CRPC was further explored in vivo.

Results

Both aptamers showed high specificity to target cells with dissociation constants in the nanomolar range, and did not recognize other tested cells. The staining of clinical tissue sections with fluorescent dye labeled aptamers showed that sections from CRPC exhibited stronger fluorescence while sections from benign prostatic hyperplasia and androgen dependent prostate cancer did not exhibit notable fluorescence. In vivo MRI demonstrated that CRda21-conjugated PEG-Fe₃O₄ had good affinity to CRPC and produced strong T2WI signal intensity reduction distinguished from peritumoral tissue.

Conclusion

The high affinity and specificity of CRda8 and CRda21 make the aptamer hold potential for early recognition of castration-resistant state and diagnosis of CRPC at the cellular level.

Keywords:

• aptamer
• Cell-SELEX
• MRI
• castration resistant prostate cancer
• androgen dependent prostate cancer

Acknowledgments

This study was supported by the National Natural Science Foundation of China (Grant number: 82102347) and the Shanxi Provincial key research and development project (Grant number: 2024SF-YBXM-417).

Disclosure

The authors declare no conflicts of interest in this work.