Circulating CD15+LOX-1+ PMN-MDSC is a potential biomarker for the
recurrence after surgery of non-small cell lung cancer
Abstract
Aims: As a population of immunosuppressive cells,
polymorphonuclear-myeloid derived suppressor cells (PMN-MDSCs) are
responsible for lung cancer metastasis, and metastasis is a main cause
of the recurrence after surgery of non-small-cell lung cancer (NSCLC).
Lectin-type oxidized LDL receptor 1 (LOX-1) is a newly confirmed maker
for identifying PMN-MDSCs in human. In this study, we tried to confirm
the relationship between the frequency of newly identified CD15+LOX-1+
PMN-MDSCs and NSCLC recurrence after surgery. Methods: Flow cytometry
(FCM) was used to detect the proportion of CD15+LOX-1+ PMN-MDSCs in the
peripheral blood (PB) cells of healthy controls (HC) and NSCLC patients.
The correlation of CD15+LOX-1+ PMN-MDSC frequency with levels of
cytokeratin 19-fragments (CYFRA21-1), carcinoembryonic antigen (CEA),
and carbohydrate antigen 125 (CA125) was analyzed. Receiver operating
characteristic (ROC) curve was used to estimate the diagnostic efficacy
of CD15+LOX-1+ PMN-MDSC frequency for NSCLC. Additionally, the
association of CD15+LOX-1+ PMN-MDSCs with NSCLC prognosis and recurrence
after surgery was explored. Results: The proportion of CD15+LOX-1+
PMN-MDSCs increased significantly in PB of NSCLC patients. CD15+LOX-1+
PMN-MDSC proportion was positively correlated with levels of CEA and
CYFRA21-1, but not CA125. The area under the ROC curve (AUC) of PMN-MDSC
percentage was higher than CYFRA21-1, CEA and CA125. Compared to NSCLC
patients before surgery, the proportion of CD15+LOX-1+ PMN-MDSCs
decreased in patients after surgery. The frequency of CD15+LOX-1+
PMN-MDSCs was lower in NSCLC patients without recurrence compared to
those with recurrence after surgery. Conclusions: Circulating
CD15+LOX-1+ PMN-MDSCs are a potential diagnostic marker for NSCLC, and
are associated with NSCLC recurrence after surgery.