Differential regulation by anti-tumor-promoting 12-deoxyphorbol-13- phenylacetate reveals distinct roles of the classical and novel protein kinase C isozymes in biological responses of primary mouse keratinocytes

Z Szallasi, K Kosa, CB Smith, AA Dlugosz, EK Williams, SH Yuspa and PM Blumberg

Laboratory of Cellular Carcinogenesis and Tumor Promotion, National Cancer Institute, Bethesda, Maryland 20892.

12-Deoxyphorbol-13-phenylacetate (dPP) is the prototype for a new class of phorbol derivatives that function as protein kinase C (PKC) activators with potent anti-tumor-promoting activity. To explore the mechanism of action of dPP, we have conducted detailed analyses of the translocation and down-regulation patterns of individual PKC isozymes in mouse primary keratinocytes upon dPP treatment. PKC-alpha, -delta, and -epsilon were very quickly (within 2-5 min) translocated from the soluble fraction to the Triton X-100-soluble particulate fraction. PKC- delta and -epsilon were translocated with 2 orders of magnitude higher potency than was PKC-alpha. After translocation, PKC-alpha, -delta, - eta, and -epsilon were down-regulated; the down-regulation of PKC- epsilon contrasts with its retention after phorbol-12-myristate-13- acetate or bryostatin treatment. As was the case with translocation, dPP down-regulated the novel PKC isozymes (delta, epsilon, and eta) with 2 orders of magnitude higher potency (ED50, about 1-2 nM), compared with PKC-alpha (ED50, about 100 nM). dPP induced transglutaminase activity, ornithine decarboxylase activity, and cornification with potencies similar to that for PKC-alpha translocation. On the other hand, dPP caused inhibition of EGF binding with a potency similar to that for the translocation of the novel PKC isozymes. Although the generality of its selectivity in different cell types remains to be determined, at least in keratinocytes dPP is a powerful tool for dissecting the involvement of the classical and novel PKC isozymes in biological responses. The unique regulatory pattern of PKC-epsilon could contribute to the anti-tumor-promoting activity of dPP.

Volume 47, Issue 2, pp. 258-265, 02/01/1995
Copyright © 1995 by American Society for Pharmacology and Experimental Therapeutics

This article has been cited by other articles:

				P. Krejci, B. Masri, L. Salazar, C. Farrington-Rock, H. Prats, L. M. Thompson, and W. R. Wilcox Bisindolylmaleimide I Suppresses Fibroblast Growth Factor-mediated Activation of Erk MAP Kinase in Chondrocytes by Preventing Shp2 Association with the Frs2 and Gab1 Adaptor Proteins J. Biol. Chem., February 2, 2007; 282(5): 2929 - 2936. [Abstract] [Full Text] [PDF]

				J. A. Knauf, L. S. Ward, Y. E. Nikiforov, M. Nikiforova, E. Puxeddu, M. Medvedovic, T. Liron, D. Mochly-Rosen, and J. A. Fagin Isozyme-Specific Abnormalities of PKC in Thyroid Cancer: Evidence for Post-Transcriptional Changes in PKC Epsilon J. Clin. Endocrinol. Metab., May 1, 2002; 87(5): 2150 - 2159. [Abstract] [Full Text] [PDF]

				M. L. Garcia-Bermejo, F. C. Leskow, T. Fujii, Q. Wang, P. M. Blumberg, M. Ohba, T. Kuroki, K.-C. Han, J. Lee, V. E. Marquez, et al. Diacylglycerol (DAG)-lactones, a New Class of Protein Kinase C (PKC) Agonists, Induce Apoptosis in LNCaP Prostate Cancer Cells by Selective Activation of PKCalpha J. Biol. Chem., January 4, 2002; 277(1): 645 - 655. [Abstract] [Full Text]

				Q. J. Wang, T.-W. Fang, D. Fenick, S. Garfield, B. Bienfait, V. E. Marquez, and P. M. Blumberg The Lipophilicity of Phorbol Esters as a Critical Factor in Determining the Pattern of Translocation of Protein Kinase C delta Fused to Green Fluorescent Protein J. Biol. Chem., April 14, 2000; 275(16): 12136 - 12146. [Abstract] [Full Text] [PDF]

				P. S. Lorenzo, K. Bogi, K. M. Hughes, M. Beheshti, D. Bhattacharyya, S. H. Garfield, G. R. Pettit, and P. M. Blumberg Differential Roles of the Tandem C1 Domains of Protein Kinase C {{delta}} in the Biphasic Down-Regulation Induced by Bryostatin 1 Cancer Res., December 1, 1999; 59(24): 6137 - 6144. [Abstract] [Full Text] [PDF]

				M. J. Caloca, M. L. Garcia-Bermejo, P. M. Blumberg, N. E. Lewin, E. Kremmer, H. Mischak, S. Wang, K. Nacro, B. Bienfait, V. E. Marquez, et al. beta 2-Chimaerin is a novel target for diacylglycerol: Binding properties and changes in subcellular localization mediated by ligand binding to its C1 domain PNAS, October 12, 1999; 96(21): 11854 - 11859. [Abstract] [Full Text] [PDF]

				Z. Szallasi, K. Bogi, S. Gohari, T. Biro, P. Acs, and P. M. Blumberg Non-equivalent Roles for the First and Second Zinc Fingers of Protein Kinase Cdelta . EFFECT OF THEIR MUTATION ON PHORBOL ESTER-INDUCED TRANSLOCATION IN NIH 3T3 CELLS J. Biol. Chem., August 2, 1996; 271(31): 18299 - 18301. [Abstract] [Full Text] [PDF]

				M. G. Kazanietz, J. J. Barchi Jr., J. G. Omichinski, and P. M. Blumberg Low Affinity Binding of Phorbol Esters to Protein Kinase C and Its Recombinant Cysteine-rich Region in the Absence of Phospholipids J. Biol. Chem., June 16, 1995; 270(24): 14679 - 14684. [Abstract] [Full Text] [PDF]