Inflammation and survival pathways: chronic lymphocytic leukemia as a model system

Area of Science:

• Molecular Biology
• Cell Biology
• Oncology

Background:

• Inflammation triggers cell survival mechanisms, primarily through anti-apoptotic Bcl-2 family proteins.
• The Pim kinase pathway also contributes to cell survival, influencing transcription, cell cycle, and protein degradation.

Purpose of the Study:

• To elucidate the mechanisms by which Bcl-2 family proteins and Pim kinases promote cell survival.
• To investigate these pathways in chronic lymphocytic leukemia (CLL) as an optimal model.
• To understand the role of microenvironment and stromal support in inducing pro-survival proteins in CLL.

Main Methods:

• Analysis of transcript and protein levels of anti-apoptotic Bcl-2 family members.
• Investigation of post-translational modifications affecting protein stability.
• Examination of Pim-mediated phosphorylation of pro-apoptotic proteins.
• Assessment of cross-talk between Bcl-2 and Pim pathways in CLL cells with stromal support.

Main Results:

• Multiple mechanisms increase Bcl-2 family protein levels and stability.
• Pim kinase activity inhibits pro-apoptotic proteins.
• Cross-talk between Bcl-2 and Pim pathways enhances CLL cell survival and maintenance.
• Stromal support contributes to the induction of pro-survival proteins.

Conclusions:

• Bcl-2 family proteins and Pim kinases are key mediators of cell survival in inflammation and hematological malignancies like CLL.
• The interplay between these pathways, influenced by the microenvironment, is critical for disease maintenance.
• Pharmacological inhibitors targeting these pathways are under development for treating hematological malignancies.