title: Clinical impacts of mammalian target of rapamycin expression in human colorectal cancers.
abstract: This study investigated the clinicopathologic roles of mammalian target of rapamycin (mTOR) expression and its relationship to carcinogenesis and tumor progression in a colorectal adenoma-adenocarcinoma model. Two colon cancer cell lines with different pathologic stages (SW480 and SW48) and 1 normal colonic epithelial cell line (FHC) were used, in addition to 119 colorectal adenocarcinomas and 32 adenomas. mTOR expression profiles at messenger RNA (mRNA) and protein levels were investigated in the cells and tissues using real-time quantification polymerase chain reaction and immunohistochemistry. The findings were correlated with the clinicopathologic features of the tumors. The colon cell line from stage III cancer (SW48) showed higher expression of mTOR mRNA than that from stage II cancer (SW480). At the tissue level, mTOR showed higher mRNA and protein expression in colorectal carcinoma than in adenoma. The mRNA and protein expression was correlated with each other in approximately one-third of the carcinomas and adenomas. High levels of mTOR mRNA expression were noted more in carcinoma or adenoma arising from the distal portion of the large intestine (P = .025 and .019, respectively). Within the colorectal cancer population, a high level of expression of mTOR mRNA was related to the presence of lymph node metastases (P = .031), advanced pathologic stage (P = .05), and presence of persistent disease or tumor recurrence (P = .035). To conclude, the study has indicated that mTOR is likely to be involved in the development and progression of colorectal cancer and is linked to cancer initiation, invasiveness, and progression.
authors.affiliation: Pathology, School of Medicine, Griffith University, Gold Coast, QLD 4222, Australia; Biology Department, College of Medicine, University of Dammam, Dammam 31451, Saudi Arabia.
authors.forename: Naif
authors.initials: N
authors.lastname: Alqurashi
authors.forename: Vinod
authors.initials: V
authors.lastname: Gopalan
authors.forename: Robert A
authors.initials: RA
authors.lastname: Smith
authors.forename: Alfred King Y
authors.initials: AK
authors.lastname: Lam
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000556:secondary*; D000236:Adenoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000378:metabolism; D009367:Neoplasm Staging; D012333:RNA, Messenger / Q000378:metabolism; D058570:TOR Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D012333:RNA, Messenger; C546842:MTOR protein, human; D058570:TOR Serine-Threonine Kinases
keywords: Carcinoma; Colorectal; Expression; mTOR