Label-Free Quantitative Comparison of Cervical Mucus Peptides in Subjects With Endocervical Adenocarcinoma and Adenocarcinoma in Situ

PURPOSE: To uncover potential diagnostic biomarkers for endocervical adenocarcinoma (EAC) and adenocarcinoma in situ (AIS). EXPERIMENTAL DESIGN: Quantitative label-free liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) peptidomics strategies were employed to profile 8 cervical mucus (CM) samples, including 3 EAC cases, 2 AIS cases and 3 normal controls (Ctrl). RESULTS: Among the 3721 exclusive peptides identified, 12 (5 up-regulated and 7 down-regulated) endogenous peptides were significantly expressed in EAC compared to healthy controls (EAC/Ctrl); 10 (7 up-regulated and 3 down-regulated) endogenous peptides were significantly expressed in AIS compared to healthy controls (AIS/Ctrl); 11 (6 up-regulated and 5 down-regulated) endogenous peptides were significantly expressed in EAC compared to AIS (EAC/AIS) (absolute fold change ≥1.5, Benjamini-Hochberg adjusted p-value ≤0.05). Among these identifications, annexin A1 (ANXA1) was found to be down-regulated both in EAC and AIS, and its unique peptide (FIENEEQEYVQTVK) may be promising indicators for cervical glandular epithelial lesions. CONCLUSION: This is the first study to utilize CM peptidomics in cervical glandular malignancies, which may reveal the novel noninvasive biomarkers for EAC and AIS.