Endocrinology, Vol 136, 5252-5259, Copyright © 1995 by Endocrine Society

ARTICLES

Rapid induction of pim-1 expression by prolactin and interleukin-2 in rat Nb2 lymphoma cells

AR Buckley, DJ Buckley, MA Leff, DS Hoover and NS Magnuson
Department of Pharmacology and Toxicology, University of North Dakota School of Medicine, Grand Forks 58202, USA.

The lactogen-dependent Nb2 lymphoma line (Nb2-11) represents a useful pre-T cell model for investigation of early molecular events coupled to PRL-stimulated cell cycle progression. Expression of pim-1, a protooncogene that encodes a conserved cytosolic serine/threonine protein kinase, is rapidly induced in hematopoietic cells upon mitogen stimulation and is thought to be important for lymphocyte activation. The present study was conducted to determine whether mitogen stimulation in Nb2-11 or lactogen-independent Nb2-SFJCD1 cells provokes pim-1 gene expression. The pim-1 transcript was undetectable in control growth-arrested Nb2-11 cultures; however, PRL rapidly stimulated its expression in a biphasic manner. Peak expression occurred within 2-4 h (> 40-fold) and was followed by a second elevation at 12 h. The effect of PRL and IL-2 to induce pim-1 at 2 h was concentration dependent and not inhibited by cycloheximide. In Nb2-SFJCD1 cells, pim-1 messenger RNA was expressed in control cultures and augmented by PRL stimulation. Results from stability studies indicated that the t1/2 values for the pim-1 transcript were 79 and 81 min in PRL-stimulated Nb2-11 cells at 2 and 12 h. However, in the lactogen-treated Nb2-SFJCD1 line, it was nearly 3-fold more stable (219 min) at 2 h compared to that determined at either 12 h or in unstimulated cultures. In other experiments, PRL- stimulated expression of the pim-1 protein was evaluated in [35S]methionine-labeled cells by immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In Nb2-11 cells, enhanced [35S]pim-1 expression paralleled its messenger RNA transcription through 8 h. Elevated [35S]pim-1 was detected within 1 h and peaked by 2-4 h. Therefore, pim-1 represents an immediate early gene induced by PRL stimulation in Nb2-11 cells. Its initial peak of transcription occurs early during G1 cell cycle progression, whereas a second elevation is coincident with the G1/S transition. These results demonstrate that mitogen-induced expression of pim-1 is a rapid event in Nb2 lymphoma cells and suggest that it may be associated with cell cycle progression.

This article has been cited by other articles:

				K. A. Felmet, M. W. Hall, R. S. B. Clark, R. Jaffe, and J. A. Carcillo Prolonged Lymphopenia, Lymphoid Depletion, and Hypoprolactinemia in Children with Nosocomial Sepsis and Multiple Organ Failure J. Immunol., March 15, 2005; 174(6): 3765 - 3772. [Abstract] [Full Text] [PDF]

				M. Bachmann, H. Hennemann, P. X. Xing, I. Hoffmann, and T. Moroy The Oncogenic Serine/Threonine Kinase Pim-1 Phosphorylates and Inhibits the Activity of Cdc25C-associated Kinase 1 (C-TAK1): A NOVEL ROLE FOR Pim-1 AT THE G2/M CELL CYCLE CHECKPOINT J. Biol. Chem., November 12, 2004; 279(46): 48319 - 48328. [Abstract] [Full Text] [PDF]

				C. M. Karp, H. Pan, M. Zhang, D. J. Buckley, L. A. Schuler, and A. R. Buckley Identification of HRPAP20: A Novel Phosphoprotein that Enhances Growth and Survival in Hormone-Responsive Tumor Cells Cancer Res., February 1, 2004; 64(3): 1016 - 1025. [Abstract] [Full Text] [PDF]

				N. Krishnan, O. Thellin, D. J. Buckley, N. D. Horseman, and A. R. Buckley Prolactin Suppresses Glucocorticoid-Induced Thymocyte Apoptosis in Vivo Endocrinology, May 1, 2003; 144(5): 2102 - 2110. [Abstract] [Full Text] [PDF]

				N. Zhu, L. M. Ramirez, R. L. Lee, N. S. Magnuson, G. A. Bishop, and M. R. Gold CD40 Signaling in B Cells Regulates the Expression of the Pim-1 Kinase Via the NF-{kappa}B Pathway J. Immunol., January 15, 2002; 168(2): 744 - 754. [Abstract] [Full Text] [PDF]

				A R Buckley Prolactin, a lymphocyte growth and survival factor Lupus, October 1, 2001; 10(10): 684 - 690. [Abstract] [PDF]

				K. E. Borg, M. Zhang, D. Hegge, R. L. Stephen, D. J. Buckley, N. S. Magnuson, and A. R. Buckley Prolactin Regulation of pim-1 Expression: Positive and Negative Promoter Elements Endocrinology, December 1, 1999; 140(12): 5659 - 5668. [Abstract] [Full Text]

				M. Zhang, M. J. Blake, P. W. Gout, D. J. Buckley, and A. R. Buckley Proteolysis of Heat Shock Transcription Factor Is Associated with Apoptosis in Rat Nb2 Lymphoma Cells Cell Growth Differ., November 1, 1999; 10(11): 759 - 767. [Abstract] [Full Text]

				J.-B. Demoulin, E. Van Roost, M. Stevens, B. Groner, and J.-C. Renauld Distinct Roles for STAT1, STAT3, and STAT5 in Differentiation Gene Induction and Apoptosis Inhibition by Interleukin-9 J. Biol. Chem., September 3, 1999; 274(36): 25855 - 25861. [Abstract] [Full Text] [PDF]

				S. Khurana, K. Liby, A. R. Buckley, and N. Ben-Jonathan Proteolysis of Human Prolactin: Resistance to Cathepsin D and Formation of a Nonangiostatic, C-Terminal 16K Fragment by Thrombin Endocrinology, September 1, 1999; 140(9): 4127 - 4132. [Abstract] [Full Text]

				T. Mochizuki, C. Kitanaka, K. Noguchi, T. Muramatsu, A. Asai, and Y. Kuchino Physical and Functional Interactions between Pim-1 Kinase and Cdc25A Phosphatase. IMPLICATIONS FOR THE Pim-1-MEDIATED ACTIVATION OF THE c-Myc SIGNALING PATHWAY J. Biol. Chem., June 25, 1999; 274(26): 18659 - 18666. [Abstract] [Full Text] [PDF]

				C. Bole-Feysot, V. Goffin, M. Edery, N. Binart, and P. A. Kelly Prolactin (PRL) and Its Receptor: Actions, Signal Transduction Pathways and Phenotypes Observed in PRL Receptor Knockout Mice Endocr. Rev., June 1, 1998; 19(3): 225 - 268. [Abstract] [Full Text]

				H. Rui, J. Xu, S. Mehta, H. Fang, J. Williams, F. Dong, and P. M. Grimley Activation of the Jak2-Stat5 Signaling Pathway in Nb2 Lymphoma Cells by an Anti-apoptotic Agent, Aurintricarboxylic Acid J. Biol. Chem., January 2, 1998; 273(1): 28 - 32. [Abstract] [Full Text] [PDF]