R21 (soluble adenylate cyclase antibody) in evaluation of lentiginous junctional melanocytic proliferations

     

    Soluble adenylyl cyclase (sAC) is a unique class of adenylyl cyclase, the enzyme responsible for generation of cAMP. cAMP is a key intracellular signaling molecule involved in regulation of melanocyte differentiation, proliferation and melanogenesis. sAC is ubiquitously expressed in many tissues1-3 and is localized in different subcellular microdomains (cytoplasm, Golgi area, nucleus). sAC generated cAMP in response to both extracellular (TNF, Netrin, NGF) or intracellular (bicarbonate, pH, calcium) signals.(2, 4-12) 

    Magro et al. have recently reported expression of sAC in benign melanocytic proliferations and melanomas using a monoclonal antibody against sAC designated R21. (13) They showed that using R21 immunohistochemistry in benign nevi sAC is expressed predominantly  in perinuclear Golgi region. In contrast,  different histological subsets of melanoma show distinct predominant patterns and intensity of staining with R21. The most striking reproducible pattern is strong pan-nuclear expression of sAC in lentigo maligna melanoma. 

    Working in collaboration with Dr. Magro and her colleagues at Cornell, we optimized immunohistochemical protol of staining with R21 for differential diagnosis between lentigo maligna, junctional nevus and lentiginous melanocytic hyperplasia. Under our conditions, 90% of lentigo malignas show nuclear expression of sAC. In contrast, nuclear expression almost never detected in nevi (including atypical dysplastic nevi). However, a subtantial percentage (25-30%) of lentiginous melanocytic hyperplasias associated with lentigo can show focal nuclear staining. (Our paper is in press in Archives of Pathology and Laboratory Medicine)

    In this project, we posted recent cases in which we used R21 immunohistochemistry to show how we interpret R21 staining in our routine practice. Please note that login is required to read a comment about each case.

    Click here to download a pdf of our optimized Leica BOND protocol for R21 staining. 

    R21 can be purchased from CEP Biotech

    References:

     

          (1) Park HY, Gilchrest BA. Signaling pathways mediating melanogenesis. [Review] [76 refs]. Cell Mol Biol (Noisy -le-grand) 1999 November;45(7):919-930.

         (2)   Tresguerres M, Levin LR, Buck J. Intracellular cAMP signaling by soluble adenylyl cyclase. Kidney Int 2011 June;79(12):1277-1288.

         (3)   Zippin JH, Chadwick PA, Levin LR, Buck J, Magro CM. Soluble adenylyl cyclase defines a nuclear cAMP microdomain in keratinocyte hyperproliferative skin diseases. J Invest Dermatol 2010 May;130(5):1279-1287.

         (4)   Cooper DM, Mons N, Karpen JW. Adenylyl cyclases and the interaction between calcium and cAMP signalling. Nature 1995 March 30;374(6521):421-424.

         (5)   Bundey RA, Insel PA. Discrete intracellular signaling domains of soluble adenylyl cyclase: camps of cAMP? Sci STKE 2004 May 4;2004(231):e19.

         (6)   Feng QP, Zuo J, Meng Y, Fang FD. [Nuclear localization region in soluble adenylyl cyclase]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 2005 June;27(3):280-284.

         (7)   Feng Q, Zhang Y, Li Y, Liu Z, Zuo J, Fang F. Two domains are critical for the nuclear localization of soluble adenylyl cyclase. Biochimie 2006 March;88(3-4):319-328.

         (8)   Krupinski J. The adenylyl cyclase family. Mol Cell Biochem 1991 May 29;104(1-2):73-79.

         (9)   Stessin AM, Zippin JH, Kamenetsky M, Hess KC, Buck J, Levin LR. Soluble adenylyl cyclase mediates nerve growth factor-induced activation of Rap1. J Biol Chem 2006 June 23;281(25):17253-17258.

       (10)   Hess KC, Jones BH, Marquez B et al. The "soluble" adenylyl cyclase in sperm mediates multiple signaling events required for fertilization. Dev Cell 2005 August;9(2):249-259.

       (11)   Zippin JH, Chen Y, Nahirney P et al. Compartmentalization of bicarbonate-sensitive adenylyl cyclase in distinct signaling microdomains. FASEB J 2003 January;17(1):82-84.

       (12)   Zippin JH, Farrell J, Huron D et al. Bicarbonate-responsive "soluble" adenylyl cyclase defines a nuclear cAMP microdomain. J Cell Biol 2004 February 16;164(4):527-534.

       (13)   Magro CM, Crowson AN, Desmaze C, Zippin JH. The sAC Antibody Profile as a Diagnostic Adjunct in the Assessment of Pigmented Lesions. Arch Dermatol. In press 2011.

     

     

    Cases associated with this research project:

  • Scottsdale 2012 Didactic Session II Lecture #8 Case Vignettes 15
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #8 Case Vignettes 14
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #8 Case Vignettes 13
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 12
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 11
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 10
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 9
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 8
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 7
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 6b
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 6a
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 5
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 4
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 3
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 2
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations
  • Scottsdale 2012 Didactic Session II Lecture #7 Case Vignettes 1
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Dr. Z's Consultations