Investigating the role of oncostatin M in cachexia-associated muscle wasting

Cachexia is a devastating syndrome responsible for the death of more than 20% of cancer patients. Cancer-associated cachexia, marked by significant weight loss and fatigue, leads to reduced quality of life and poor survival. Although inflammatory cytokines are identified as the causative agents of muscle atrophy, current anti-cytokine therapies have not successfully attenuated muscle wasting in cancer patients. Through our examination of muscle gene expression, we identified Oncostatin M (OSM) as a strong inducer of muscle atrophy. OSM causes atrophy in primary myotubes through the JAK/STAT3 pathway. RNA sequencing shows that OSM potently induces the expression of atrophy markers and multiple potential atrophy-related genes. Overexpression of OSM by intramuscular adenovirus injection leads to muscle wasting in mice. Muscle-specific deletion of the OSM receptor (OSMR) in tumor-bearing mice rescues the cachexia-driven loss of muscle mass and function. OSM is upregulated in the plasma of cachectic mice; neutralizing circulating OSM helps preserve muscle mass and strength in tumor-bearing mice. OSMR transcripts are elevated in many muscle disorders including Facioscapulohumeral Dystrophy (FSHD) and Duchenne muscular dystrophy (DMD). Taken together, these results suggest that the OSM/OSMR signaling plays a crucial role in inducing muscle atrophy and targeting this pathway may help prevent muscle wasting.