MUC4 and liposarcoma: MDM2, which stands for mouse double minutes 2, was expressed in the liposarcoma tissue in these cases (Figure 4), MDM2 is a protein that is typically overexpressed in liposarcoma. Positive p16 expression indicates that tumor cells in this case of liposarcoma express the p16 protein (Figure 5). The absence of MUC4 expression (Table 1) in liposarcoma showed that this particular marker is not a dominant characteristic of this tumor type (Figure 6), which can assist in identifying it from other malignancies that may express MUC4.