IPA analysis of the death receptor signaling pathway suggests that cyclin D1 (encoded by the CCND1 gene) may play an upstream role in gastric cancer cell apoptosis via ABCC4 (ATP binding cassette subfamily C member 4), BCLAF1 (BCL2 Associated Transcription Factor 1), KMT2A (Lysine Methyltransferase 2A), KNL1 (Kinetochore Scaffold 1), RACGAP1 (Rac GTPase activating protein 1), and ZNF148 (Zinc Finger Protein 148) (Fig. 5I). Here, RACGAP1 is linked to gastric cancer.