MAPK8 and neoplasm: However, although JNK clearly plays an important role in Src + RasACT tumourigenesis, the activation of JNK signalling with RasACT does not result in as aggressive tumours as with Src + RasACT [51], which might be due to the contribution of Src signalling to Hippo pathway impairment [44] or to possible effects of Src on the activation of Myosin II activity and actinomyosin cell contractility, cell shape changes and tissue growth [74].