Related Experiment Videos
Insulin receptor expression in Burkitt lymphoma cell lines
1Burnet Clinical Research Unit, Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, Parkville, Victoria, Australia.
International Journal of Cancer
|September 15, 1989
Summary
Burkitt lymphoma cells show significantly reduced insulin receptors compared to normal cells, linked to decreased receptor mRNA and potential processing defects. This may reflect their less activated state.
Area of Science:
- Oncology
- Molecular Biology
- Immunology
Background:
- Burkitt lymphoma is characterized by specific chromosomal translocations.
- Insulin receptors play a role in cellular function and are typically absent on resting B cells.
Purpose of the Study:
- To investigate insulin receptor expression and function in Burkitt lymphoma cell lines.
- To explore the relationship between insulin receptors, major histocompatibility antigens, and c-myc in Burkitt lymphoma.
Main Methods:
- Comparing insulin binding to Burkitt lymphoma cells versus normal lymphoblastoid cells.
- Analyzing insulin receptor subunits and mRNA levels using cell-surface labeling.
- Assessing insulin-stimulated beta subunit auto-phosphorylation and precursor receptor forms.
- Evaluating the expression of class-1 MHC antigens and c-myc.
Main Results:
- Burkitt lymphoma cells exhibited >90% decrease in insulin binding sites compared to lymphoblastoid cells, with no change in affinity.
- Reduced insulin receptor alpha and beta subunits, and decreased insulin receptor mRNA were observed in Burkitt cells.
- Negligible insulin-stimulated beta subunit auto-phosphorylation and increased precursor receptor forms were noted in Burkitt cells.
- Four Burkitt cell lines showed 45-100% reduction in class-1 MHC antigens; insulin receptor expression correlated with MHC class-1 antigens.
- An inverse correlation was found between c-myc expression and both insulin receptors and class-1 MHC antigens.
Conclusions:
- Decreased insulin receptor expression in Burkitt lymphoma cells is associated with reduced receptor mRNA and potentially defective processing.
- The reduced insulin receptor expression may indicate a less activated cellular phenotype in Burkitt lymphoma compared to lymphoblastoid cells.
- Insulin receptor expression correlates with class-1 MHC antigens and inversely with c-myc, suggesting complex regulatory interactions in Burkitt lymphoma.