IRE1 contributes to cancer cell survival through several mechanisms. By activating XBP1, IRE1 can enhance the ability of cancer cells to manage ER stress, thus preventing apoptosis. Additionally, IRE1's RIDD activity can degrade pro-apoptotic mRNAs, further contributing to cell survival. The IRE1-XBP1 pathway can also promote angiogenesis, a process critical for tumor growth and metastasis, by upregulating pro-angiogenic factors.
