title: Calpain activity is increased in skeletal muscle from gastric cancer patients with no or minimal weight loss.
abstract: The influence of cancer on skeletal muscle calpain expression and activity in humans is poorly understood. We tested the hypothesis that calpain activity is increased in skeletal muscle from gastric cancer patients with no or <5% weight loss. Muscle biopsies were obtained from rectus abdominis muscle in 15 patients who underwent surgery for gastric cancer and had <5% weight loss and also in 15 control patients. Calpain activity was determined using a calpain-specific substrate in the absence or presence of calcium. The expression of μ- and m-calpain, calpastatin, atrogin-1, and MuRF1 was determined by real-time polymerase chain reaction. Calpain activity was increased by 70% in cancer patients compared with controls. There were no differences in mRNA levels for μ- and m-calpain, calpastatin, atrogin-1, or MuRF1 between control and cancer patients. Calpain activity may be increased in muscle from gastric cancer patients even before changes in molecular markers of muscle wasting and significant weight loss occur.
authors.affiliation: Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Ira J
authors.initials: IJ
authors.lastname: Smith
authors.forename: Zaira
authors.initials: Z
authors.lastname: Aversa
authors.forename: Per-Olof
authors.initials: PO
authors.lastname: Hasselgren
authors.forename: Fabio
authors.initials: F
authors.lastname: Pacelli
authors.forename: Fausto
authors.initials: F
authors.lastname: Rosa
authors.forename: Giovan Battista
authors.initials: GB
authors.lastname: Doglietto
authors.forename: Maurizio
authors.initials: M
authors.lastname: Bossola
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology / Q000473:pathology / Q000503:physiopathology; D000368:Aged; D002154:Calpain / Q000378:metabolism*; D004789:Enzyme Activation / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000201:enzymology* / Q000473:pathology; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D013274:Stomach Neoplasms / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology; D025801:Ubiquitin / Q000378:metabolism; D015431:Weight Loss / Q000502:physiology*
chemical_list: D012333:RNA, Messenger; D025801:Ubiquitin; D002154:Calpain; D046988:Proteasome Endopeptidase Complex