Coordinate expression of the PI3-kinase downstream effectors serum and glucocorticoid-induced kinase (SGK-1) and Akt-1 in human breast cancer

• Published in: European journal of cancer (1990) Vol. 41; no. 17; pp. 2754 - 2759
• Main Authors: Sahoo, Sunati, Brickley, Deanna R., Kocherginsky, Masha, Conzen, Suzanne D.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.11.2005; Elsevier
• Subjects: Adult; Aged; Akt-1; Biological and medical sciences; Breast cancer; Breast Neoplasms - enzymology; Caenorhabditis elegans; Female; Humans; Immediate-Early Proteins - metabolism; Immunohistochemistry; Immunohistochemistry - methods; Insulin signalling; Medical sciences; Middle Aged; Pharmacology. Drug treatments; Phosphatidylinositol 3-Kinases - metabolism; PI3-kinase; Protein-Serine-Threonine Kinases - metabolism; Proto-Oncogene Proteins c-akt - metabolism; SGK-1; Tumors; Immunohistochemistry; Akt-1; SGK-1; Breast cancer; PI3-kinase; Insulin signalling; Human; Pancreatic hormone; Enzyme; Transferases; Akt protein kinase; Pharmacology; Malignant tumor; P13-kinase; Effector; Glucocorticoid; Insulin; 1-Phosphatidylinositol 3-kinase; Mammary gland diseases; Signal transduction; Anatomic pathology; Cancerology; Kinase; Serum
• ISSN: 0959-8049; 1879-0852
• DOI: 10.1016/j.ejca.2005.07.018

The phosphatidylinositol 3-kinase (PI3-K) signalling pathway has been implicated in breast cancer development and resistance to therapy. Akt-1 and serum and glucocorticoid-induced kinase-1 (SGK-1) are homologous kinases which are important downstream effectors of PI3-K signalling. We sought to determine the individual expression patterns of these two kinases in order to better understand their respective roles in PI3-K signalling in breast cancer. To this end, we examined the expression of both p-Akt-1 and SGK-1 in 40 breast cancers. p-Akt-1 expression was seen in 58% of tumour samples, while SGK-1 overexpression was detected in 48%. Interestingly, a highly significant association was found between the expression of p-Akt-1 and SGK-1 ( P = 0.002), suggesting complementary physiological functions in PI3-K signalling. This finding is consistent with recent genetic data from Caenorhabditis elegans suggesting that both SGK-1 and Akt-1 are required for signalling downstream of insulin receptor activation.