Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:The phosphorylated C and D motifs have been shown to interact with SHP-2 phosphatase, leading to cellular rearrangements and the formation of long cellular protrusions in AGS gastric epithelial cells (Higashi et al., 2002b).
Category: