A recent study has found that a drug derived from an ocean sponge and one from a European evergreen combine to prevent the spread of cancer cells.
The study, published in the July issue of Cancer Research, found that the sponge-based drug, discodermolide, works with a yew tree derivative called paclitaxel to thwart tumor cell growth.
Inhibited cancer cells by 41%
The researchers found that the combination of the two drugs inhibited proliferation of human lung cancer cells by 41%. Administered alone, discodermolide or paclitaxel prevented the cancer cell growth by only 9.6% or 16%, respectively. The drugs also combined to induce programmed cell death—or apoptosis—in the lung cancer cells.
The drugs, which stem from naturally occurring sources, work in concert to stabilize the assembly/disassembly process of microtubules in cells. Microtubules form long, straw-like cylinders that help shape the skeletal structure within cells and also move cellular components. Their attachment with chromosomes is critical for cell replication and growth. Microtubules normally exist in a state of dynamic instability, where the polymers grow rapidly—longer or shorter, depending on the need of the cells.
Kills cancer cells
The scientists found that the drugs combined to alter the overall microtubule dynamics by 71% when administered together. Alone, they only reduced microtubule dynamic instability by 24%.
By altering the stability dynamics of microtubules, paclitaxel and discodermolide limit cancer cells ability to duplicate DNA and divide. The cells are stuck in a pre-division stage of the cell cycle. Cancer cells that are restricted to the pre-division stage cannot divide and will die, thus reducing spread of tumor cells.
Reference:
1. S. Honore; et al., “Synergistic Suppression of Microtubule Dynamics by Discodermolide and Paclitaxel in Non-Small Cell Lung Carcinoma Cells,” Cancer Research, 2004: 64: 4957-4964.
