Translocation Processes of Pt(II)-Based Drugs through Human Breast Cancer Cell Membrane: In Silico Experiments.

Area of Science:

• Biophysics
• Computational Chemistry
• Oncology

Background:

• Breast cancer remains a significant global health concern with high mortality rates.
• Platinum-based drugs like cisplatin, carboplatin, and oxaliplatin are standard chemotherapy but face challenges with side effects and resistance.
• Understanding drug transport mechanisms at the molecular level is crucial for improving breast cancer treatment.

Purpose of the Study:

• To investigate the molecular dynamics of platinum-based drug translocation across human breast cancer cell membranes.
• To elucidate the role of membrane lipids in the passive influx and efflux of these chemotherapy agents.
• To provide insights into the factors limiting platinum drug permeability in breast cancer.

Main Methods:

• Utilized molecular dynamics (MD) simulations to model the passive translocation of platinum drugs.
• Employed a realistic plasma membrane model of a human breast cancer cell (c_memb).
• Analyzed drug-membrane interactions, including lipid mediation, membrane deformation, and energy landscapes (Potentials of Mean Force - PMF).

Main Results:

• Permeation was primarily mediated by neutral lipids (DOPC, DOPE, cholesterol) with minimal membrane deformation.
• Drug insertion into the polar head region of the membrane was energetically favorable for cisplatin and oxaliplatin.
• Significant energy barriers were observed for drug permeation through lipid tails, hindering translocation kinetics.
• Carboplatin and oxaliplatin exhibited significantly lower permeability coefficients compared to cisplatin due to these barriers.

Conclusions:

• Molecular dynamics simulations offer a detailed view of platinum drug permeation in breast cancer cells.
• Lipid composition and membrane structure present substantial kinetic barriers to platinum drug translocation.
• These findings are vital for the rational design and development of novel platinum-based anticancer agents with improved efficacy.