Serum Epcam And BSG As Detectable Circulating Tumor Cell Associated Biomarkers For Diagnosis And Chemotherapy Monitoring In Lung Cancer Patients By Using ELISA

Abstract

Background: Lung cancer continues to be one of the major causes of cancer-related deaths globally and requires novel minimally invasive biomarkers for diagnosis and during systemic therapy. Circulating tumor cell-associated proteins could be used as dynamic markers of tumor burden and biological changes associated with chemotherapy.

Objective: This study aimed to assess the potential of serum epithelial cell adhesion molecule (EpCAM) and Basigin (BSG) as Protein expression detectable circulating tumor cell-associated biomarkers in lung cancer patients with focus on diagnostic performance, modulation by chemotherapy and correlation with the tumor aggressiveness.

Methods: This was an analytical case-control study that incorporated lung cancer patients and healthy controls. Enzyme-linked immunosorbent assay (ELISA) was used for measuring the levels of serum EpCAM and BSG (Protein expression). The distribution of the biomarkers was mostly non-normal, therefore Kruskal-Wallis and Dunn post-hoc testing, Mann-Whitney U test, Spearman correlation, receiver operating characteristic (ROC) analysis, and DeLong comparison of AUCs were performed as non-parametric analysis of these values.

Conclusion: EpCAM and BSG was significantly higher in the serum of lung cancer patients than in the controls. Median EpCAM was higher in patients than controls (7.65 vs. 5.75 ng/mL, p < 0.001), while BSG showed a more pronounced increase (624.53 vs. 117.77 ng/mL, p < 0.001). BSG showed the highest effect size (r = 0.67) and the highest diagnostic accuracy (AUC = 0.939; DeLong p = 0.004) compared with EpCAM (AUC = 0.768; DeLong p = 0.139). The relationship of both BSG and EpCAM with the number of chemotherapy doses was found to be moderately negative (rho = -0.42, p<0.001) and moderately positive (rho = 0.22, p=0.09), respectively, with higher stage and grade, while stage and grade were not significantly associated with EpCAM. EpCAM and BSG are valuable Protein expression detectable markers in cancer of the lung. BSG seems to be a better option for discrimination of the cancer for diagnosis, monitoring treatment with chemotherapy, and representing the general aggressiveness of the cancer. The authors recommend larger longitudinal studies with a standardized clinical response endpoint prior to routine clinical use.