MAPK3 and metastatic neoplasm: Accordingly, in a panel of already characterized human sarcoma specimens [7], low cytoplasmic p27/stathmin ratio was significantly associated with high levels of ERK1/2 phosphorylation (Figure 8D) and, when sarcoma specimens were segregated in primary vs metastatic tumors, we observed that metastatic tumors specimens displayed a significant lower p27/stathmin ratio coupled with a significantly higher ERK activation (Figure 8E).