Quantitative Analysis of CD27/CD70 Protein Expression and Investigation of Related Mechanisms in the Tumor Microenvironment of NSCLC.

Background/aim: Lung cancer is among the cancers with the highest mortality rates worldwide. Biomarkers associated with it are critically important for diagnosis, evaluation of clinicopathological features, and the development of treatment strategies.

Patients and methods: In this study, a total of 32 NSCLC primary tumor tissues and 32 matching 32 normal tissues were analyzed with Western Blot for CD70, CD27, CD3, and FOXP3; positive and negative results were evaluated according to a quantitative analysis of expression with ImageJ. Furthermore, the levels of sCD27 in the serum samples of 30 NSCLC patients and 32 healthy controls were investigated by ELISA.

Results: CD70 expression was observed in 5/32 (15.63%) NSCLC tumors, CD27 in 24/32 (75%), CD3 in 28/32 (87.5%), and FOXP3 in 14/32 (43.75%) tumor tissues, all significantly differing from normal tissues (p<0.0001). The mean serum sCD27 level in NSCLC patients (117.29±38.18 U/ml) was considerably higher than in controls (p<0.0001). Positive CD70 expression in tumors was significantly correlated with higher serum sCD27 levels compared to CD70-negative tumors (x0.007). No significant association was found between overall survival and sCD27 status (p=0.779).

Conclusion: The findings suggest that the CD27/CD70 pathway is a potential diagnostic and therapeutic target in NSCLC. Serum sCD27 levels may serve as a diagnostic biomarker. CD70, CD27, CD3 and FOXP3 quantifications show that CD70 is expressed in NSCLC, and related molecular mechanisms support previous findings. However, further studies are required with larger cohorts in NSCLC.