This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ding, W.-Q. Articles by Miller, L. J. Search for Related Content PubMed PubMed Citation Articles by Ding, W.-Q. Articles by Miller, L. J.

A Misspliced Form of the Cholecystokinin-B/Gastrin Receptor in Pancreatic Carcinoma

Role of Reduced Cellular U2AF35 and a Suboptimal 3'-Splicing Site Leading to Retention of the Fourth Intron¹

Center for Basic Research in Digestive Diseases and the Department of Biochemistry/Molecular Biology, Mayo Clinic and Foundation, Rochester, Minnesota 55905

Abnormal splicing of primary RNA transcripts of normal genes is a recognized mechanism for the production of some abnormal proteins found in cancer cells. A misspliced form of the cholecystokinin-B/gastrin (CCK-B) receptor recently was reported to be present in colon carcinoma, where it was postulated to play a role in stimulating tumor growth (M. R. Hellmich et al., J. Biol. Chem., 275: 32122–32128, 2000). Here, we report the presence of the same abnormal protein in pancreatic carcinoma and explore the molecular basis for this missplicing event. Reverse transcription-PCR and sequencing were used to demonstrate the presence of a misspliced form of the CCK-B receptor having its fourth intron retained in three pancreatic cancer cell lines and in tumor tissue, but not in surrounding healthy pancreas, from two patients with pancreatic carcinoma. A mini-gene construct representing the region of this gene from its third through its fifth exon and containing the two intervening introns was produced and transiently expressed in the MIA PaCa-2 human pancreatic cancer cell line. Specific reverse transcription-PCR reactions with both vector-derived and receptor-specific primers demonstrated the presence of both correctly fully spliced and selectively misspliced forms of this receptor. Mutagenesis of the mini-gene demonstrated that a suboptimal sequence at the 3'-end of intron 4 contributed to this missplicing. This focused attention on the U2 small nuclear ribonucleoprotein particle auxiliary splicing factors (U2AFs) known to interact specifically with this domain. Indeed, quantitative real-time PCR demonstrated a reduced level of expression of one of these factors, U2AF35, in pancreatic cancer cells compared with healthy pancreas. Furthermore, the relative amount of missplicing of the CCK-B receptor mini-gene in the pancreatic cancer cell line was reversed by transfection of the cells with U2AF35 cDNA. This work describes the presence of an additional abnormal protein in pancreatic cancer and describes a new molecular mechanism for its production, providing additional potential therapeutic targets.

This article has been cited by other articles:

				E. Marco, M. Foucaud, I. Langer, C. Escrieut, I. G. Tikhonova, and D. Fourmy Mechanism of Activation of a G Protein-coupled Receptor, the Human Cholecystokinin-2 Receptor J. Biol. Chem., September 28, 2007; 282(39): 28779 - 28790. [Abstract] [Full Text] [PDF]

				M. R. Paillasse, C. Deraeve, P. de Medina, L. Mhamdi, G. Favre, M. Poirot, and S. Silvente-Poirot Insights into the Cholecystokinin 2 Receptor Binding Site and Processes of Activation Mol. Pharmacol., December 1, 2006; 70(6): 1935 - 1945. [Abstract] [Full Text] [PDF]

				M. Dufresne, C. Seva, and D. Fourmy Cholecystokinin and gastrin receptors. Physiol Rev, July 1, 2006; 86(3): 805 - 847. [Abstract] [Full Text] [PDF]

				G. M. Hayes, P. E. Carrigan, A. M. Beck, and L. J. Miller Targeting the RNA splicing machinery as a novel treatment strategy for pancreatic carcinoma. Cancer Res., April 1, 2006; 66(7): 3819 - 3827. [Abstract] [Full Text] [PDF]

				C. Chao, K. L. Ives, E. Goluszko, A. A. Kolokoltsov, R. A. Davey, C. M. Townsend Jr., and M. R. Hellmich Src Regulates Constitutive Internalization and Rapid Resensitization of a Cholecystokinin 2 Receptor Splice Variant J. Biol. Chem., September 30, 2005; 280(39): 33368 - 33373. [Abstract] [Full Text] [PDF]

				C. Bierkamp, S. Bonhoure, A. Mathieu, P. Clerc, D. Fourmy, L. Pradayrol, C. Seva, and M. Dufresne Expression of Cholecystokinin-2/Gastrin Receptor in the Murine Pancreas Modulates Cell Adhesion and Cell Differentiation in Vivo Am. J. Pathol., December 1, 2004; 165(6): 2135 - 2145. [Abstract] [Full Text] [PDF]

				J. P. Venables Aberrant and Alternative Splicing in Cancer Cancer Res., November 1, 2004; 64(21): 7647 - 7654. [Abstract] [Full Text] [PDF]

				B. Olszewska-Pazdrak, C. M. Townsend Jr., and M. R. Hellmich Agonist-independent Activation of Src Tyrosine Kinase by a Cholecystokinin-2 (CCK2) Receptor Splice Variant J. Biol. Chem., September 24, 2004; 279(39): 40400 - 40404. [Abstract] [Full Text] [PDF]

				Z.-J. Cheng, K. G. Harikumar, E. L. Holicky, and L. J. Miller Heterodimerization of Type A and B Cholecystokinin Receptors Enhance Signaling and Promote Cell Growth J. Biol. Chem., December 26, 2003; 278(52): 52972 - 52979. [Abstract] [Full Text] [PDF]

				R. P. Thomas, M. R. Hellmich, C. M. Townsend Jr., and B. M. Evers Role of Gastrointestinal Hormones in the Proliferation of Normal and Neoplastic Tissues Endocr. Rev., October 1, 2003; 24(5): 571 - 599. [Abstract] [Full Text] [PDF]

				J. C. Reubi Peptide Receptors as Molecular Targets for Cancer Diagnosis and Therapy Endocr. Rev., August 1, 2003; 24(4): 389 - 427. [Abstract] [Full Text] [PDF]

				R. Huang, Z. Xing, Z. Luan, T. Wu, X. Wu, and G. Hu A Specific Splicing Variant of SVH, a Novel Human Armadillo Repeat Protein, Is Up-Regulated in Hepatocellular Carcinomas Cancer Res., July 1, 2003; 63(13): 3775 - 3782. [Abstract] [Full Text] [PDF]

				M. Mine, M. Brivet, G. Touati, P. Grabowski, M. Abitbol, and C. Marsac Splicing Error in E1alpha Pyruvate Dehydrogenase mRNA Caused by Novel Intronic Mutation Responsible for Lactic Acidosis and Mental Retardation J. Biol. Chem., March 28, 2003; 278(14): 11768 - 11772. [Abstract] [Full Text] [PDF]

				R. Sorek and H. M. Safer A novel algorithm for computational identification of contaminated EST libraries Nucleic Acids Res., February 1, 2003; 31(3): 1067 - 1074. [Abstract] [Full Text] [PDF]

				G. Halmos, A. V. Schally, T. Czompoly, M. Krupa, J. L. Varga, and Z. Rekasi Expression of Growth Hormone-Releasing Hormone and Its Receptor Splice Variants in Human Prostate Cancer J. Clin. Endocrinol. Metab., October 1, 2002; 87(10): 4707 - 4714. [Abstract] [Full Text] [PDF]

				W.-Q. Ding, Z.-J. Cheng, J. McElhiney, S. M. Kuntz, and L. J. Miller Silencing of Secretin Receptor Function by Dimerization with a Misspliced Variant Secretin Receptor in Ductal Pancreatic Adenocarcinoma Cancer Res., September 15, 2002; 62(18): 5223 - 5229. [Abstract] [Full Text] [PDF]