TY - JOUR
T1 - Phosphorylated akt and phosphorylated mtor expression in breast invasive carcinomas
T2 - Analysis of 530 cases
AU - An, Jungsuk
AU - Jeong, Hoiseon
AU - Lee, Youngseok
AU - Woo, Sang Uk
AU - Seo, Jae Hong
AU - Kim, Aeree
PY - 2010/12
Y1 - 2010/12
N2 - Purpose: The phosphatidylinositol 3-kinase (PI3K)/Akt/ mammalian target of rapamycin (mTOR) pathway has a central role in regulation of cell proliferation, differentiation, motility and survival. This pathway has recently generated great interest because its elements are, potentially, novel targets for the treatment of various malignancies, including breast cancer. Methods: Using tissue microarray sections of breast carcinoma, we performed immunohistochemical studies using antibodies against the phosphorylated forms of Akt (p-Akt) and mTOR (p-mTOR) in 530 invasive breast carcinomas and 30 ductal carcinomas in situ (DCIS). We investigated possible associations between expression of these proteins and clinicopathologic characteristics and disease outcomes. Results: In 530 invasive carcinomas, weak and strong expression of p-Akt was observed in 180 (34.0%) and 288 (54.3%) cases, respectively. The expression of p-Akt was associated with expression of estrogen receptors (ER) (p=0.045), progesterone receptors (PR) (p=0.003), lymph node metastasis (p<0.001) and cancer stage (p=0.027). Weak and strong expression of p-mTOR was found in 136 (25.7%) and 207 (39.1%) cases, respectively. The mTOR pathway was more frequently activated in DCIS than in invasive breast carcinoma (p=0.001). p-mTOR expression was associated with expression of ER (p=0.040), PR (p=0.009), tumor size (p<0.001), and stage (p=0.002). In a univariate analysis, strong expression of p-Akt was associated with longer disease-free survival (DFS). In a multivariate analysis, neither p-Akt nor p-mTOR was associated with DFS. Conclusion: The PI3K/Akt/mTOR pathway is active in DCIS as well as in invasive carcinoma of the breast. Our study also suggests that the PI3K/Akt/mTOR pathway is influenced by ER rather than erbB-2, and that this pathway may contribute more to cancer pathogenesis in ER-positive tumors.
AB - Purpose: The phosphatidylinositol 3-kinase (PI3K)/Akt/ mammalian target of rapamycin (mTOR) pathway has a central role in regulation of cell proliferation, differentiation, motility and survival. This pathway has recently generated great interest because its elements are, potentially, novel targets for the treatment of various malignancies, including breast cancer. Methods: Using tissue microarray sections of breast carcinoma, we performed immunohistochemical studies using antibodies against the phosphorylated forms of Akt (p-Akt) and mTOR (p-mTOR) in 530 invasive breast carcinomas and 30 ductal carcinomas in situ (DCIS). We investigated possible associations between expression of these proteins and clinicopathologic characteristics and disease outcomes. Results: In 530 invasive carcinomas, weak and strong expression of p-Akt was observed in 180 (34.0%) and 288 (54.3%) cases, respectively. The expression of p-Akt was associated with expression of estrogen receptors (ER) (p=0.045), progesterone receptors (PR) (p=0.003), lymph node metastasis (p<0.001) and cancer stage (p=0.027). Weak and strong expression of p-mTOR was found in 136 (25.7%) and 207 (39.1%) cases, respectively. The mTOR pathway was more frequently activated in DCIS than in invasive breast carcinoma (p=0.001). p-mTOR expression was associated with expression of ER (p=0.040), PR (p=0.009), tumor size (p<0.001), and stage (p=0.002). In a univariate analysis, strong expression of p-Akt was associated with longer disease-free survival (DFS). In a multivariate analysis, neither p-Akt nor p-mTOR was associated with DFS. Conclusion: The PI3K/Akt/mTOR pathway is active in DCIS as well as in invasive carcinoma of the breast. Our study also suggests that the PI3K/Akt/mTOR pathway is influenced by ER rather than erbB-2, and that this pathway may contribute more to cancer pathogenesis in ER-positive tumors.
KW - Breast
KW - Carcinoma
KW - Proto-oncogene protein c-akt
KW - mTOR protein
UR - http://www.scopus.com/inward/record.url?scp=79251486345&partnerID=8YFLogxK
U2 - 10.4048/jbc.2010.13.4.337
DO - 10.4048/jbc.2010.13.4.337
M3 - Article
AN - SCOPUS:79251486345
VL - 13
SP - 337
EP - 348
JO - Journal of Breast Cancer
JF - Journal of Breast Cancer
SN - 1738-6756
IS - 4
ER -