We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress hp
Sign In
Advertise with Us
LGC Clinical Diagnostics

Download Mobile App




MYC Oncogene Activity in B-Cell Lymphoma Depends on the CD19 Surface Marker

By LabMedica International staff writers
Posted on 22 May 2012
Print article
Cancer researchers specializing in B-cell lymphomas have uncovered a previously unknown relationship between the oncogene MYC and the B-cell surface receptor CD19.

MYC is a very strong proto-oncogene, and it is very often found to be upregulated in many types of cancers. The Myc protein encoded by this gene is a transcription factor that activates expression of a great number of genes through binding on consensus sequences (Enhancer Box sequences (E-boxes)) and recruiting histone acetyltransferases (HATs). It can also act as a transcriptional repressor. By binding Miz-1 transcription factor and displacing the p300 coactivator, it inhibits expression of Miz-1 target genes. MYC is activated upon various mitogenic signals such as Wnt, Shh, and EGF (via the MAPK/ERK pathway). By modifying the expression of its target genes, MYC activation results in numerous biological effects. The protein encoded by MYC has been found to be highly resistant to chemotherapy mainly because it lacks efficient binding sites for drug compounds.

CD19 is a 95 kDa transmembrane glycoprotein with two Ig-like C2-set domains. CD19 regulates B-cell development and activation through interactions with CD21, CD22, and the B-cell receptor. CD19 polymorphisms and upregulation lead to the development of autoimmunity by promoting autoantibody production. Its downregulation is associated with the malignant phenotype in multiple myeloma.

Investigators at the University of Pennsylvania (Philadelphia, USA) worked with two different lymphoma cell lines: a MYC-induced mouse lymphoma model as well as a MYC-transformed human B-cell line.

They reported in the May 1, 2012, online edition of the Journal of Clinical Investigation that Myc levels in B-cells from CD19-deficient mice were sharply reduced. Conversely, reexpression of CD19 in mouse lymphomas with spontaneous silencing of the CD19 activator PAX5 (paired box protein-5) boosted Myc levels, expression of its key target genes, cell proliferation in vitro, and overall tumor growth in vivo. In human B-cell lymphomas, CD19 mRNA levels were found to correlate with those of MYC-activated genes. They also negatively correlated with the overall survival of patients with lymphoma in the same way that Myc levels do. Thus, CD19 was shown to be a major regulator of MYC-driven cancerous growth in B-cell lymphomas.

“Our research suggests ways to devise more specific therapies to selectively kill tumor cells in a subset of lymphomas,” said senior author Dr. Andrei Thomas-Tikhonenko, associate professor of pathology and laboratory medicine at the University of Pennsylvania. “We found that CD19 is absolutely required to stabilize the Myc protein. When Myc is stable and present in high levels, it fuels cancer. Patients with high levels of the Myc protein are more likely to die of lymphoma. Without CD19, there is no Myc, so controlling that on-off switch could represent a powerful tool against lymphoma.”

Related Links:

University of Pennsylvania


Gold Member
Veterinary Hematology Analyzer
Exigo H400
Verification Panels for Assay Development & QC
Seroconversion Panels
New
Silver Member
Verification Panels for Assay Development & QC
Seroconversion Panels
New
Mycoplasma Pneumoniae Virus Test
Mycoplasma Pneumoniae Virus Detection Kit

Print article

Channels

Molecular Diagnostics

view channel
Image: Researcher Kanta Horie places a sample in a mass spectrometer that measures protein levels in blood plasma and other fluids (Photo courtesy of WashU Medicine)

Highly Accurate Blood Test Diagnoses Alzheimer’s and Measures Dementia Progression

Several blood tests are currently available to assist doctors in diagnosing Alzheimer's disease in individuals experiencing cognitive symptoms. However, these tests do not provide insights into the clinical... Read more

Immunology

view channel
Image: The findings were based on patients from the ADAURA clinical trial of the targeted therapy osimertinib for patients with NSCLC with EGFR-activated mutations (Photo courtesy of YSM Multimedia Team)

Post-Treatment Blood Test Could Inform Future Cancer Therapy Decisions

In the ongoing advancement of personalized medicine, a new study has provided evidence supporting the use of a tool that detects cancer-derived molecules in the blood of lung cancer patients years after... Read more

Microbiology

view channel
Image: Schematic representation illustrating the key findings of the study (Photo courtesy of UNIST)

Breakthrough Diagnostic Technology Identifies Bacterial Infections with Almost 100% Accuracy within Three Hours

Rapid and precise identification of pathogenic microbes in patient samples is essential for the effective treatment of acute infectious diseases, such as sepsis. The fluorescence in situ hybridization... Read more
Copyright © 2000-2025 Globetech Media. All rights reserved.