RareBoost Seminar: Prof. Fahri Saatçıoğlu “Endoplasmic reticulum stress signaling in cancer cells and the tumor microenvironment – Implications for cancer immunotherapy”
We welcome you to the next RareBoost Seminar, presented by Prof. Fahri Saatçıoğlu (University of Oslo), on 18 December 2025 at 11:00 am at IBG Aziz Sancar Auditorium.
Prof. Saatçığlu will deliver a seminar titled: “Endoplasmic reticulum stress signaling in cancer cells and the tumor microenvironment – Implications for cancer immunotherapy”
Prof. Fahri Saatçıoğlu is a molecular and cell biologist trained at Maharishi International University (Fairfield, Iowa) and the University of California, San Diego. Since 1996, he has led a research group at the University of Oslo in Norway focusing on hormone action, stress signaling, and carcinogenesis.
We look forward to your participation.
Seminar abstract
Endoplasmic reticulum (ER) is the largest organelle in the cell. Among others, it functions as a stress sensor responding to increased demand for protein production and folding under both physiological and pathological conditions. ER stress initiates a series of coping mechanisms that are termed the unfolded protein response (UPR), which restructures the cellular transcriptional, translational, and degradation pathways to help resolve the defects in protein folding. We have found that the activity of IRE1α-XBP1s signaling, one of three canonical UPR pathways, is increased in human prostate cancer (PCa) specimens. Consistently, genetic or pharmacological inhibition of IRE1α-XBP1s signaling in multiple syngeneic or orthotopic mouse PCa models dramatically reduced tumor growth. Multiomics analysis of tumor samples upon IRE1α deletion in cancer cells showed significantly potentiated interferon (IFN) response and activation of immune system related pathways in the TME. Single-cell RNA sequencing revealed that the abundance of immunosuppressive cells were markedly reduced in the IRE1α deficient tumors. Importantly, IRE1α inhibition by a small molecule MKC8866 (ORIN1001) enhanced anti-PD-1 checkpoint inhibitor therapy in syngeneic mouse PCa models. Our findings indicate that IRE1α not only promotes cancer cell growth and survival, but it also strongly inhibits anti-tumor immunity in the PCa TME.
About the speaker:
Prof. Fahri Saatçıoğlu is a molecular and cell biologist trained at Maharishi International University and the University of California, San Diego. Since 1996, he has led a research group at the University of Oslo focusing on hormone action, stress signaling, and carcinogenesis. Beyond his distinguished scientific career, he is a dedicated yoga practitioner and instructor.