Immunohistochemistry staining for MTSS1 in HCC and paired normal tissues (200×). A: Normal (non-neoplastic) liver tissue; B and C: positive expression of MTSS1 in well-(B) and moderate-(C) differentiated tumors. D: poorly differentiated cancer cells without MTSS1 expression (long arrow) infiltrated into normal liver cell panel with MTSS1 high expression (short arrow); E: MTSS1 expression was lower in the tumor foci (arrow) compared with around non-neoplastic liver tissue; F: MTSS1 expression is low in tumor thromboses (short arrow) and primary HCC (long arrow). G: The positive rate of MTSS1 in HCC tissues (43%) was significantly lower than that of normal tissues (79%). Furthermore, the positive rate (17%) in patients with metastasis (tumor number ≥2) was significantly lower than that of cases without metastasis (50%). ** p < 0.01.