RHEB expression in fibroadenomas of the breast.
Although fibroadenoma is one of the most common types of benign breast tumor, genes specific to the tumor have not been identified. Microarrays were used to identify differentially expressed genes between fibroadenoma and infiltrating ductal carcinoma. The comparative expression of one of the identified genes, RAS homolog enriched in the brain (RHEB), was further explored using reverse transcriptase-polymerase chain reaction (RT-PCR). Microarray analysis was performed on tissue samples from five patients with fibroadenoma. In the fibroadenoma samples, the genes HDAC1, ROS1, TNFRSF10A, WASP2, TYRP1, WEE1, and RHEB were expressed at levels more than twofold higher than in the normal tissues. RT-PCR for RHEB indicated increased expression of RHEB in fibroadenoma compared to breast cancer. When studied with real-time PCR, the average RHEB/beta-actin ratio in fibroadenoma samples was 1.99, 2.46-fold greater than the average RHEB/beta-actin ratio in breast carcinoma of 0.81 (P < 0.01). Immunohistochemistry and PCR followed by microdissection shows increased expression of RHEB in epithelial cells compared to the stromal cells of fibroadenoma. Therefore, RHEB could be used cytopathologically to distinguish fibroadenoma from malignant breast carcinomas as a secondary diagnostic tool.
Eom
Minseob
M
Department of Pathology, Wonju College of Medicine, Yonsei University, Wonju, Korea.
Han
Airi
A
Yi
Sang Yeop
SY
Shin
John Junghun
JJ
Cui
Ying
Y
Park
Kwang Hwa
KH
D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism; D005260:Female; D018226:Fibroadenoma / Q000235:genetics* / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007124:Immunoenzyme Techniques; D008408:Mastectomy; D042282:Microdissection; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism; D000076205:Ras Homolog Enriched in Brain Protein; D020133:Reverse Transcriptase Polymerase Chain Reaction
D014408:Biomarkers, Tumor; D009479:Neuropeptides; C490211:RHEB protein, human; D012333:RNA, Messenger; D000076205:Ras Homolog Enriched in Brain Protein; D020559:Monomeric GTP-Binding Proteins