Faculty Collaboration Database

Insertion of c-Myc into Igh induces B-cell and plasma-cell neoplasms in mice. Cancer Res 2005 Feb 15;65(4):1306-15

Date

03/01/2005

Pubmed ID

15735016

DOI

10.1158/0008-5472.CAN-04-0268

Abstract

We used gene targeting in mice to insert a His(6)-tagged mouse c-Myc cDNA, Myc(His), head to head into the mouse immunoglobulin heavy-chain locus, Igh, just 5' of the intronic enhancer, Emu. The insertion of Myc(His) mimicked both the human t(8;14)(q24;q32) translocation that results in the activation of MYC in human endemic Burkitt lymphomas and the homologous mouse T(12;15) translocation that deregulates Myc in certain mouse plasmacytomas. Beginning at the age of 6 months, Myc(His) transgenic mice developed B-cell and plasma neoplasms, such as IgM(+) lymphoblastic B-cell lymphomas, Bcl-6(+) diffuse large B-cell lymphomas, and CD138(+) plasmacytomas, with an overall incidence of 68% by 21 months. Molecular studies of lymphoblastic B-cell lymphoma, the most prevalent neoplasm (50% of all tumors), showed that the lymphomas were clonal, overexpressed Myc(His), and exhibited the P2 to P1 promoter shift in Myc expression, a hallmark of MYC/Myc deregulation in human endemic Burkitt lymphoma and mouse plasmacytoma. Only 1 (6.3%) of 16 lymphoblastic B-cell lymphomas contained a BL-typical point mutation in the amino-terminal transactivation domain of Myc(His), suggesting that most of these tumors are derived from naive, pregerminal center B cells. Twelve (46%) of 26 lymphoblastic B-cell lymphomas exhibited changes in the p19(Arf)-Mdm2-p53 tumor suppressor axis, an important pathway for Myc-dependent apoptosis. We conclude that Myc(His) insertion into Igh predictably induces B-cell and plasma-cell tumors in mice, providing a valuable mouse model for understanding the transformation-inducing consequences of the MYC/Myc-activating endemic Burkitt lymphoma t(8;14)/plasmacytoma T(12;15) translocation.

Author List

Park SS, Kim JS, Tessarollo L, Owens JD, Peng L, Han SS, Tae Chung S, Torrey TA, Cheung WC, Polakiewicz RD, McNeil N, Ried T, Mushinski JF, Morse HC 3rd, Janz S

Author

Siegfried Janz MD Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Amino Acid Sequence
Animals
B-Lymphocytes
Burkitt Lymphoma
Chromosomes, Human, Pair 14
Chromosomes, Human, Pair 8
Disease Models, Animal
Genes, Tumor Suppressor
Genes, myc
Humans
Immunoglobulin Heavy Chains
Lymphoma, B-Cell
Mice
Molecular Sequence Data
Plasmacytoma
Point Mutation
Precancerous Conditions
Promoter Regions, Genetic
Transgenes
Translocation, Genetic