Cancer Prevention and Epidemiology Research
Systemic Chromosome Instability Resulted in Colonic Transcriptomic Changes in Metabolic, Proliferation, and Stem Cell Regulators in Sgo1 /þ Mice Chinthalapally V. Rao1, Saira Sanghera2, Yuting Zhang1, Laura Biddick1, Arun Reddy1, Stan Lightfoot1, Naveena B. Janakiram1, Altaf Mohammed1, Wei Dai3, and Hiroshi Y.Yamada1
Abstract
Colon cancer is the second most lethal cancer and is pre- genes, 132 downregulated genes, P < 0.05). Pathway analyses dicted to claim 49,700 lives in the United States this year. indicated that the Sgo1-CIN tissues upregulated pathways Chromosome instability (CIN) is observed in 80% to 90% of known to be activated in colon cancer, including lipid metab- colon cancers and is thought to contribute to colon cancer olism (z score 4.47), Notch signaling (4.47), insulin signaling progression and recurrence. To investigate the impact of CIN (3.81), and PPAR pathways (3.75), and downregulated path- on colon cancer development, we developed shugoshin-1 ways involved in immune responses including allograft rejec- (Sgo1) haploinsufficient ( /þ) mice, an animal model focus- tion (6.69) and graft-versus-host disease (6.54). Notably, ing on mitotic error–induced CIN. In this study, we analyzed stem cell markers were also misregulated. Collectively, our þ signature changes in the colonic transcriptome of Sgo1 / findings demonstrate that systemic CIN results in transcrip- mice to examine the molecular events underlying the altered tomic changes in metabolism, proliferation, cell fate, and þ carcinogenesis profiles in Sgo1 / mice. We performed next- immune responses in the colon, which may foster a microen- generation sequencing of normal-looking colonic mucosal vironment amenable to cancer development. Therefore, ther- tissue from mice treated with the carcinogen azoxymethane apeutic approaches focusing on these identified pathways after 24 weeks. Transcriptome profiling revealed 349 hits with may be valuable for colon cancer prevention and treatment. a 2-fold expression difference threshold (217 upregulated Cancer Res; 76(3); 630–42. 2016 AACR.
Introduction repair pathways (4). As colon cancer is the second most lethal cancer and is predicted to claim 49,700 lives this year in the Chromosome instability (CIN) is primarily caused by United States alone (5), investigating CIN has high clinical impaired mitotic fidelity, and leads to aneuploidy (1). CIN relevance. The high prevalence of CIN among colon cancer may and aneuploidy are hallmarks of numerous cancers. In addi- be due to CIN-causing mutations' involvement in colonic tion, CIN is especially prevalent in colon cancer (80%–90%) carcinogenesis itself. Many gene mutations that occur frequent- and is associated with poor prognosis (2). A study in Mad2-CIN ly in colon cancer, such as mutations in TP53, APC, and FBXW7 mice model even suggested that CIN is causal to higher cancer (6), can cause CIN, suggesting a strong link between the recurrence (3). The remaining 10% to 20% of cases are asso- initiation and progression of colonic carcinogenesis and CIN ciated with microsatellite instability (MIN), which is primarily (7). Researchers have attempted to use various model systems, caused by defects in DNA metabolism, especially in mismatch including Drosophila (8), yeast (9), and aneuploid mice (10), to characterize CIN and aneuploidy, in hopes of elucidating the relationship between CIN and carcinogenesis and of devel- 1 Center for Cancer Prevention and Drug Development, Department of oping a CIN/aneuploidy-targeting approach for cancer preven- Medicine, Hematology/Oncology Section, University of Oklahoma – /þ Health Sciences Center, Oklahoma City, Oklahoma. 2College of Arts tion or therapy (11 14). Models of CIN, including BubR1 , /þ /þ & Sciences, Baylor University, Waco, Texas. 3Department of Environ- Mad2 ,andcenpe mice, demonstrated organ-specific mental Medicine, New York University Langone Medical Center, oncogenic and tumor-suppressing effects (15. 16). Tuxedo, New York. We developed a mouse model of CIN, the haploinsuffi- Note: Supplementary data for this article are available at Cancer Research cient ( /þ) Shugoshin 1 (Sgo1) mouse. Approximately 48% of Online (http://cancerres.aacrjournals.org/). human colon cancers expressed less than 50% of Sgo1 mRNA Corresponding Author: Hiroshi Y. Yamada, Department of Medicine, Hematol- (17), and 13% expressed abnormal dominant-negative Sgo1 ogy/Oncology Section, University of Oklahoma Health Sciences Center transcript (18), suggesting a role of Sgo1 in human colon cancer. (OUHSC), 975 NE 10th St. BRC1207, Oklahoma City, OK 73104. Phone: 405- Sgo1 protein plays dual roles in cells as a centrosome compo- 227-8001, ext. 32524; Fax: 405-271-3225; E-mail: [email protected] nent and as an accessory factor for the cohesin-mediated teth- doi: 10.1158/0008-5472.CAN-15-0940 ering of mitotic chromosomes. Sgo1 insufficiency resulted in 2016 American Association for Cancer Research. reduced Sgo1 protein and partial loss of function. Consistently,
630 Cancer Res; 76(3) February 1, 2016
Downloaded from cancerres.aacrjournals.org on September 25, 2021. © 2016 American Association for Cancer Research. Impact of CIN on Colon