Disruption of Cytoskeleton Induces Physiologically and Morphologically Dysfunctional Mitochondria in B-ALL Cells.

The interaction of cellular organelles is crucial for maintaining intracellular homeostasis, particularly highlighting the impact of the cytoskeleton on mitochondrial dynamics. The aim of our study is to find direct molecular connections between cytoskeletal disturbance and mitochondrial failure which are inadequately characterized particularly in B-ALL. We investigated the effects of cytoskeleton inhibition on mitochondria in B-ALL using Pironetin (an alpha-tubulin inhibitor) and Latrunculin B (an actin inhibitor). Our findings indicate that these inhibitors caused mitochondrial fragmentation, characterized by smaller, rounder mitochondria with disordered cristae, increased Drp1 expression (fission protein), and decreased Mfn 1/2 and OPA 1 (fusion proteins) together with significantly modified the expression of essential mitochondrial transporters, such as VDAC and ANT2. These alterations were linked to increased mitochondrial membrane depolarization & mitochondrial reactive oxygen species and gradual mtDNA depletion, indicative of impaired oxidative phosphorylation (increased non-mitochondrial oxygen consumption, decreased mitochondrial reserve capacity) and diminished mitochondrial functionality. These mitochondrial alterations indicate that communication between the cytoskeleton and mitochondria is essential for preserving mitochondrial homeostasis. This study potentially enhances our understanding of how cancer cells modulate mitochondrial function during progression or therapeutic interventions.