CSPG4 and fibrosarcoma: In a study by Benassi et al. (2009), mRNA expression of a proteoglycan neuron-glial antigen 2 (NG2), also known as chondroitin sulphate proteoglycan 4 (CSPG4) was analysed in fresh frozen primary samples of 16 malignant fibrous histiocytomas, 22 leiomyosarcomas, 11 liposarcomas and 6 fibrosarcomas.