HsClpP-Engaging Selective Mitochondrial Pan-PDK Degraders for Cancer Therapy

Selective degradation of mitochondrial proteins remains a significant challenge due to the unique compartmentalization and proteostasis mechanisms of this organelle. Here, we report A1, a mitochondria-targeted small-molecule degrader that selectively eliminates pyruvate dehydrogenase kinases (PDKs) by recruiting the mitochondrial protease HsClpP, achieving nanomolar degradation potency (DC₅0 ≈ 10 nM). Mechanistically, A1 induces efficient pan-PDK degradation, thereby rewiring mitochondrial metabolism toward enhanced oxidative phosphorylation. This metabolic shift promotes the accumulation of reactive oxygen species (ROS), leading to opening of the mitochondrial permeability transition pore (mPTP) and activation of the intrinsic mitochondrial apoptosis. Notably, A1 also elicits hallmark features of immunogenic cell death (ICD), including calreticulin exposure and HMGB1 release, thereby stimulating antitumor immune responses. Consistent with these findings, A1 markedly suppresses both primary and distal tumor growth, with selective PDK degradation in tumor tissues and no observable systemic toxicity. Collectively, these results establish mitochondria-targeted degradation of metabolic enzymes as a promising therapeutic strategy for cancer.