title: Are tumoral factors responsible for host tissue wasting in cancer cachexia?
abstract: Both cytokines and tumor factors have been implicated in tissue loss in cancer cachexia. Loss of adipose tissue is most likely due to the tumor (and host) factor zinc-alpha2-glycoprotein because of its direct lipolytic effect, ability to sensitize adipocytes to lipolytic stimuli and increased expression in cachexia. TNF-alpha and the tumor factor proteolysis-inducing factor are the major contenders for skeletal muscle atrophy; both increase protein degradation through the ubiquitin-proteasome pathway and depress protein synthesis through phosphorylation of eukaryotic initiation factor 2 alpha. However, while most studies report proteolysis-inducing factor levels to correlate with the appearance of cachexia, there is some disagreement regarding a correlation between serum levels of TNF-alpha and weight loss. Furthermore, only antagonists to proteolysis inducing factor prevent muscle loss in cancer patients, suggesting that tumor factors are the most important.
authors.affiliation: Nutritional Biomedicine, School of Life & Health Sciences, Aston University, Birmingham, B4 7ET, UK. m.j.tisdale@aston.ac.uk
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Tisdale
mesh_terms: D002100:Cachexia / Q000150:complications / Q000503:physiopathology*; D016207:Cytokines / Q000235:genetics / Q000502:physiology*; D006801:Humans; D009369:Neoplasms / Q000150:complications / Q000235:genetics / Q000503:physiopathology*; D048069:Tumor Necrosis Factors / Q000378:metabolism*
chemical_list: D016207:Cytokines; D048069:Tumor Necrosis Factors