Objective: To identify practical biomarkers used in diagnosis of ovarian cancer.
Methods: Peripheral blood samples were collected from 59 ovarian cancer patients, 64 ovarian benign tumors patients, and 142 healthy women and underwent column chromatography to purify the target proteins. The proteins thus obtained were identified with matrix-assisted desorption ionization tissue-of-flight mass spectrometry (MALDI-TOF MS). Immunohistochemistry was used to detect the expression of CCL18 and CXCL1 in the cancer tissues. ELISA was used to detect the serum CC118 and CXCL1 contents. Receiver operating characteristic curve was drawn to examine the sensitivity and specificity of the potential biomarker to ovarian cancer.
Results: The m/z 7,784 and 7,837 proteins were identified as chemokine CC2 motif ligand 18 (CCL18) and CXC Chemokines ligand 1 (CXCL1) respectively. The serum levels of CCL18 and CXCL1 of the patients with ovarian cancer were 150 +/- 62 ng/ml and 1 +/- 0.4 ng/ml respectively, both were significantly higher than those of the healthy control women and the patients with ovarian benign diseases (all P < 0.05). The diagnostic sensitivity and specificity of CXCL1 to ovarian cancer were 100% and 97.8% respectively. The diagnostic sensitivity of CCL18 was 100% to ovarian cancer of stages I-II and 86.1% to ovarian cancer of stages III-IV. The CCL18 positive rate in the cancer tissue was 84.6% and the CXCL1 expression rate was 96.2%. The model established based the combination of both biomarkers had the sensitivity and specificity to ovarian cancer of both 100%.
Conclusion: CCL18 and CXCL1 may be used in early screening of ovarian cancer.