The significance of immune-regulatory molecule B7-H4 in small cell lung cancer

Background: B7-H4, a member of the B7 family, is detected in various cancers and is closely related to tumor development and prognosis. However, little is known about the clinical value of B7-H4 in small cell lung cancer (SCLC). Methods: Immunohistochemical analysis was carried out on 103 SCLC specimens. The relationship between B7-H4 staining and the major clinical parameters of SCLC was analyzed, and the two-year survival rates were investigated by chi-square test. Results: Only 5.83% of the SCLC specimens tested positive for B7-H4. B7-H4 was detected on the membrane and in the cytoplasm of tumor cells. In contrast, B7-H4 expression was not detected in normal lung tissue samples. B7-H4 was not found to be associated with major clinical parameters, such as tumor size, gender, age, smoking status, limited/extensive stage, tumor node metastasis, Karnofsky Performance Status, lymph node metastasis status, distant metastasis, or ki-67. Moreover, no obvious differences were observed in the two-year survival rates of B7-H4 positive or B7-H4-negative SCLC patients. Conclusions: There is no correlation between B7-H4 expression and the proliferation or progression of SCLC. Therefore, B7-H4 is not a useful biomarker for SCLC prognosis.