Systemic modeling myeloma-osteoclast interactions under normoxic/hypoxic condition using a novel computational...

Area of Science:

• * Oncology
• * Cell Biology
• * Bioinformatics

Background:

• * Multiple myeloma cells interact with osteoclasts (OCs) within the bone marrow, a hypoxic niche.
• * This interaction enhances tumor cell expansion via complex signaling networks.
• * The impact of this interaction under hypoxia on myeloma growth and drug response remains unclear.

Purpose of the Study:

• * To investigate how osteoclast-myeloma cell interactions in normoxic and hypoxic conditions affect myeloma cell signaling and drug response.
• * To computationally infer osteoclast-mediated myeloma cell-specific signaling pathways.

Main Methods:

• * Protein profiling using reverse phase protein array on myeloma cells cultured with/without OCs under normoxia and hypoxia.
• * Development of an Integer Linear Programming approach to model signaling pathways.
• * In silico simulation of drug treatment effects by pathway perturbation.

Main Results:

• * Under normoxia with OCs, PI3K/AKT and MEK/ERK pathways were activated, and apoptosis regulators BAX/BIM were downregulated.
• * Under hypoxia with OCs, the β1 Integrin/FAK signaling pathway was activated in myeloma cells.
• * Simulated drug treatments indicated that combining PI3K and integrin inhibitors could inhibit proliferation (normoxia) and migration/invasion (hypoxia).

Conclusions:

• * Osteoclast interaction significantly alters myeloma cell signaling pathways under both normoxic and hypoxic conditions.
• * Targeting PI3K/AKT and β1 Integrin/FAK pathways offers a potential therapeutic strategy for multiple myeloma.
• * Combined inhibition may overcome drug resistance by modulating key proliferation and invasion pathways.