Thrombomodulin (TM) in tumor cell differentiation and periphery blood immune microenvironment in oral squamous cell carcinoma

Thrombomodulin (TM, also known as CD141), which functions as an anticoagulant, is widely expressed on cell surface of a variety of cell types, including human blood cells as well as certain immune cells. To determine whether TM could be a potential marker for OSCC diagnosis as well as a molecular target for OSCC therapy, we examined the expression of TM in an oral cancer tissue microarray with 153 oral cancer tissues. Further, we also analyzed the expression of TM on DCs of 36 OSCC patients and 36 healthy donors. The expression of TM was determined using standard immunohistochemistry on a tissue microarray of 153 OSCC patients. Flow cytometric analyses were performed to determine the proportions of CD141⁺ DCs in the PBMC of 36 OSCC patients and 36 healthy donors. Clinicopathological correlations were performed based on the available clinical data. Our results showed that in the univariate analysis, high TM expression was significantly associated with well differentiation of tumor cells (P =.001), but not correlated with overall survival and disease-free survival (P >.05). In addition, CD141⁺ DCs were both present in OSCC patients and healthy donors with about 0.04%. There was no significant difference with the percentages of CD141⁺ DCs in the PBMC of OSCC patients and that of the normal control group (P >.05). This study indicates that TM expression might play the most critical role in the differentiation of OSCC tumors. Functional distinctions of CD141⁺ DCs in OSCC patients deserve further investigation to provide important therapeutic understandings for future immunotherapy.