MMP1 and neoplasm: Furthermore, Grnd is likely to be involved in both polarity-impairment-induced cell competition and cooperative tumourigenesis – clones with scrib knockdown die, while those with knockdown of both scrib and grnd survive, and the invasiveness of Ras85DV12/scrib–/– tumours is blocked via grnd knockdown, as is their overexpression of the JNK target, Mmp1 (Andersen et al., 2015).