N-myristoyltransferase: a potential novel diagnostic marker for colon cancer.
BACKGROUND
Colon cancer is the second leading cause of cancer deaths in the western world. If detected early, colorectal cancer is one of the most treatable forms of cancer. Unfortunately, very few people are screened. N-myristoyltransferase (NMT) catalyzes myristoylation of various proteins including oncoproteins. We have demonstrated earlier the alteration of NMT activity during the progression of colorectal cancer and established NMT as a putative therapeutic target for cancer.


METHODS
Peripheral blood samples and bone marrow were collected from the colon cancer patients and azoxymethane induced colonic tumor rats and their controls respectively. NMT activity and expression was determined as reported earlier. Immunohistochemical studies were carried out using standard procedures.


RESULTS
In this study we demonstrate for the first time altered expression and localization of NMT in the peripheral blood and bone marrow in colon cancer patients. Immunohistochemical analysis revealed weak to negative staining for NMT in peripheral blood mononuclear cells (PBMC) of controls, whereas strong positivity was observed in PBMC colon cancer patients. In addition, we observed that NMT was localized mostly in the nuclei of the bone marrow (BM) mononuclear cells of the colon cancer patients, whereas NMT remained cytoplasmic in the control bone marrow specimens.


CONCLUSIONS
The strikingly different NMT expression offers the basis of a potential adjunct investigative tool for screening or diagnosis of patients at risk for or suspected of having colon cancer. Furthermore, altered localization of NMT in BM of tumor bearing hosts may serve as an added investigative tool for the diagnostic purpose.
Shrivastav
Anuraag
A
Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon, Canada S7N 5E5. anuraag.shrivastav@saskcancer.ca
Varma
Shailly
S
Saxena
Anurag
A
DeCoteau
John
J
Sharma
Rajendra K
RK
D000217:Acyltransferases / Q000097:blood / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001854:Bone Marrow Cells / Q000378:metabolism; D002384:Catalysis; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008297:Male; D009363:Neoplasm Proteins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D000217:Acyltransferases; C050480:glycylpeptide N-tetradecanoyltransferase