Nimodipine Used with Vincristine: Protects Schwann Cells and Neuronal Cells from Vincristine-Induced Cell Death but Increases Tumor Cell Susceptibility.

The chemotherapeutic agent vincristine is commonly used for a variety of hematologic cancers, as well as solid tumors of the head and neck, bronchial carcinoma, as part of the procarbazine, lomustine and vincristine (PCV) regimen, for glioma. Damage to nerve tissue (neuropathy) is often dose-limiting and restricts treatment. Nimodipine is a calcium antagonist that has also shown neuroprotective properties in preliminary studies. In this approach here, we investigated the effects of the combination of vincristine and nimodipine on three cancer cell lines (A549, SAS and LN229) and neuronal cells (RN33B, SW10). Fluorescence microscopy, lactate dehydrogenase (LDH) assays and Western blot analyses were used. Nimodipine was able to enhance the cell death effects of vincristine in all tumor cells, while neuronal cells were protected and showed less cell death. There was an opposite change in the protein levels of Ak strain transforming/protein kinase B (AKT) in tumor cells (down) and neuronal cells (up), with simultaneous increased protein levels of cyclic adenosine monophosphate response element-binding protein (CREB) in all cell lines. In the future, this approach may improve tumor response to chemotherapy and reduce unwanted side effects such as neuropathy.