Background
The androgen receptor (AR) is an ~110 kDa androgen-dependent transcription factor that is a member of the steroid/nuclear receptor gene superfamily.  The AR signaling pathway plays a key role in development and function of male reproductive organs, including the prostate and epididymis. AR also plays a role in nonreproductive organs, such as muscle, hair follicles, and brain.  Abnormalities in the AR signaling pathway have been linked to a number of diseases, including prostate cancer, Kennedy's disease and male infertility.   The PI3K/Akt signaling pathway plays an important role in regulating AR activity through phosphorylation of AR at Ser213/210 and Ser791/790.  Growth factors or cytokines may induce phosphorylation of AR through the PI3K/Akt pathway.  IGF-1 activates the  phosphatidylinositol 3-kinase(PI3K)/AKT pathway in LNCap at high passage number and increases phosphorylation of of  AR at Ser213/210 (see western blot) and Ser791/790 (Lin et al. 2003).  The western blot results also show that inhibition of the PI3K/Akt pathway by LY294002 prior to incubation with IGF-1 suppressed AR phosphorylation at Ser213/210.  Activation of the PI3K/AKt pathway is thought to have a survival role in prostate cancer by protecting cells from apoptosis. 

Antigen
This antibody was developed against a synthetic peptide corresponding to amino acids 207-221 (GRAREAS*GAPTSSKD) of human androgen receptor, containing the serine 213 phosphorylation site: GenBank Accession No. A39248.  Note: S* refers to phosphorylated serine in the peptide sequence.

Application Notes
In IGF-1 stimulated LNCaP cells (passage number 38), a ~110 kDa band was observed.  Please see Lin et al. 2003 for additional details. The serine phosphorylation site recognized by this antibody has been alternatively referred to Ser213 (Lee and Chang, 2003) and Ser210 (Lin et al, 2003).  Variations in denotation can arise from how the sequence is counted in various GenBank accession numbers.  The site is denoted as Ser213 in GenBank Accession No. A39248, which was used to design the immunogen.

Related Products

Reference
1. Dong, KL and C Chang. 2003. Expression and degradation of androgen receptor: mechanism and clinical implication. J Clinical Endrocrinology & Metabolism. 88:4043-4054.

Product Citations
1. Suppression Versus Induction of Androgen Receptor Functions by the Phosphatidylinositol 3-Kinase/Akt Pathway in Prostate Cancer LNCaP Cells with Different Passage Numbers. Lin, H-K., Y-C Hu, L. Yang, S. Altuwaijri. 2003.  J. Biol. Chem. 278: 50902-50907.
2. A neuroactive steroid 5a-androstane-3a,17ß-diol regulates androgen receptor level in astrocytes. Agapova OA, PE Malone and MR Hernandez. Journal of Neurochemistry, 98: 355-363 (2006). WB: Fig 5A (primary cultures of human optic nerve head astrocytes treated with various agents).  Astrocytes were immunoprecipitated with an antibody recognizing total androgen receptor, followed by western blot with IMG-561 to detect phosphorylated androgen receptor.
3. Observer variation in immunohistochemical analysis of protein expression, time for a change? Kirkegaard T, Edwards J, Tovey S, McGlynn L M, Krishna S N, Mukherjee R, Tam L, Munro A F, Dunne B & Bartlett J M S. Histopathology 48, 787–794 (2006).
4. Down-regulation of Androgen Receptor by 3,3'-Diindolylmethane Contributes to Inhibition of Cell Proliferation and Induction of Apoptosis in Both Hormone-Sensitive LNCaP and Insensitive C4-2B Prostate Cancer Cells. Mohammad M.R. Bhuiyan, Yiwei Li, Sanjeev Banerjee, Fakhara Ahmed, Zhiwei Wang, Shadan Ali, and Fazlul H. Sarkar. Cancer Res., 66: 10064-10072 (2006).
5. Akt blocks ligand binding and protects against expanded polyglutamine androgen receptor toxicity. Palazzolo I, BG Burnett, JE Young, PL Brenne, AR La Spada, KH fishbeck, BW Howell and M Pennuto. Human Molecular Genetics 16:1593-1603 (2007). WB: Cos cells transfected or mock-transfected with AR sequences: Fig B-D
6. Hyaluronan stimulates transformation of androgen-independent prostate cancer. Lin S-L, D Chang, and S-Y Ying. Carcinogenesis 28:310-320 (2007).
Imgenex products cited:
1. Prostate Cancer Tissue Microarray (IMH-303): IHC (paraffin), Figs 2D, 4B and 6. The Androgen Receptor (Ser213/210) mAb (IMG-561) is used in Fig 6  

2. Androgen Receptor (Ser213/210) mAb (IMG-561): IHC (paraffin), Fig 6. This antibody is used to label Prostate Cancer Tissue Microarrys (IMH-303).