Potential utility of ADNP in circulating tumor cells as biomarker for prognostics in non-muscle-invasive bladder cancer

This study aims to evaluate the prognostic utility of Activity-dependent neuroprotective protein (ADNP) expression in Circulating Tumor Cells (CTCs) inpatients with Non-muscle-invasive Bladder Cancer (NMIBC) undergoing Transurethral Resection of Bladder Tumor (TURBT). A prospective cohort of 74 bladder cancer patients and 22 non-cancer controls were enrolled. The expression of ADNP mRNA was detected by immunomagnetic beads-droplet digital PCR. The ADNP mRNA expression was evaluated in patients with high-risk NMIBC and those with indeterminate invasion depth post 2nd TURBT. Primary cultured bladder cancer cells and PBMCs from healthy donors were immunofluorescence stained. Our findings suggest that baseline ADNP mRNA level in CTCs shows potential as a prognostic marker for NMIBC with a sensitivity of 83.33% and a specificity of 73.58%. In comparison to baseline, ADNP mRNA expression increased post 2nd TURBT in 5 patients, where 2 experienced recurrence. Meanwhile, among the 12 patients with decreased levels, only one patient relapsed. A considerable limitation of this study entails the small sample size. The Immuno-magnetic beads-ddPCR technique provided a viable method for ADNP mRNA detection in CTCs from bladder cancer patients. The preoperative ADNP mRNA level in CTCs was identified as a prognostic indicator for NMIBC. Longitudinal monitoring of ADNP mRNA in CTCs of bladder cancer patients shows promise in evaluating treatment responses and predicting prognosis.