Stress response mechanisms

Stress response mechanisms refer to the coordinated network of cellular signaling pathways activated to maintain homeostasis or trigger programmed cell death in response to internal or external insults. Key pathways include the Integrated Stress Response (ISR), which converges on the phosphorylation of eIF2α to regulate protein synthesis, and the Unfolded Protein Response (UPR), which manages endoplasmic reticulum stress. These mechanisms are frequently hijacked by cancer cells to survive harsh tumor environments, nutrient deprivation, and chemotherapy, making specific components of these pathways attractive but complex therapeutic targets. In neurodegenerative diseases, chronic activation of these stress responses can lead to persistent translation inhibition and eventual neuronal loss. Pharmacological intervention typically focuses on specific nodes like Hsp90, PERK, or eIF2α rather than the entire mechanism. Because the term encompasses a broad range of distinct proteins, transcription factors, and organelles, it is classified as a biological process rather than a singular molecular target.

Other names

Cellular stress responseIntegrated stress response (ISR)Unfolded protein response (UPR)Heat shock response (HSR)Oncogenic stress responseProteostasis networkDNA damage response (DDR)

Modulation of eIF2α phosphorylation, inhibition of molecular chaperones (e.g., Hsp90), activation of stress-sensitive transcription factors (e.g., ATF4, HSF1, XBP1), and induction of ER-associated degradation (ERAD).