A study of inter-alpha-trypsin inhibitor chains expression in liposarcomas

Aim: Liposarcoma is common soft tissue sarcoma that is sometimes difficult to treat, besides its good prognosis. The inter-α-trypsin inhibitor heavy chains (HCs) has been reported to be linked to hyaluronan, which play important roles in tumour progression and metastasis. In this study, clinical significance of HCs in patients with liposarcoma was investigated. Methods: HC expression was studied by immunohistochemistry on resected specimens of 33 liposarcoma patients and 10 lipoma patients. The expression of HC mRNA was analyzed by reverse transcription polymerase chain reaction (RT-PCR). Serum concentration of HC was determined with enzyme-linked immunosorbent assay (ELISA). Results: Prominent positive staining of HC was observed in extracellular matrix of pleomorphic and myxoid liposarcoma. In well-differentiated liposarcoma and lipoma, faint staining was seen with HC. No products of HC could be detected by RT-PCR. Serum concentration of HC was not up-regulated in any subtypes of liposarcoma. HC expression was not significantly correlated with tumour subtypes and prognosis. Conclusion: HC was strongly accumulated in pleomorphic and myxoid liposarcoma, however, was not locally synthesized in liposarcoma. HC might play roles in stabilizing extracellular matrix, such as hyaluronan (HA), in liposarcoma.