Targeting cancer cells
From determining a link between protein and cancer to the breakthrough treatment of tumor immunotherapy, cancer researchers are making extraordinary strides.
This is an exciting time in cancer research. From multibillion dollar medical research complexes to smaller university laboratories, cancer researchers are making extraordinary discoveries about the cellular mechanics of cancer.
Cancer is a complex disease. Why, researchers wonder, does a nonsmoker develop lung cancer while a smoker remains disease-free? Or, how does a world-class athlete at the peak of his physical health develop an aggressively dangerous malignancy? What is different about patients who respond to therapy and those who do not? This month’s Research Watch is a snapshot of the efforts being made to understand what turns cancer on and off.
Understanding Cancer Cell Metabolism
Cancer cell proteins work like little on/off switches. Researchers have long suspected that combinations of proteins work together to make cancer cells unrecognizable to the body’s immune system and to play a role in proliferation and chemo-resistance.
Last year, 2007, was a breakthrough year in understanding the intricacies of cancer cell metabolism. US researchers at the National Cancer Institute (NCI) identified a protein interaction that has a significant role in some metastatic sarcomas. Past work on metastasis has focused on the absence of certain proteins. This work reveals for the first time that changes to and destruction of a protein drives the spread of cancer.
The NCI announcement was followed a few weeks later with the discovery by Cambridge University scientists of the proteins that make ovarian cancer cells sensitive or resistant to taxanes, a class of chemotherapy drugs derived from the bark of the Pacific yew tree (Taxus brevifolia). With this knowledge, doctors may soon be able to target taxane use to patients who will benefit the most.
Other research teams are designing immune cells that target specific cancer cell proteins. The goal of tumour immunotherapy is to help the body marshal an immune response directed precisely at cancer cells. Once at the very cutting edge of cancer research, immunotherapy mechanisms are expected to enter clinical trials within a few years.
Mother Nature’s Chemistry Set
Understanding the complex cellular world of cancer is only half of the story. Researchers are making unprecedented strides in isolating and understanding the anticancer properties found in plant-based antioxidants.
Many studies have shown that the complete array of antioxidant compounds found in foods such as red wine or green tea are more effective cancer fighters than are individual compounds.
Researchers at Purdue University have moved the knowledge another step forward. Their work revealed that combining antioxidants from different foods produced a synergistic anticancer effect. They compared the anticancer activity of grapes and grape skin extracts alone to that of grapes combined with green tea. Red wine and green tea, used together, exhibited a strong action against cancer cell activity and growth.
A host of studies have also examined the anticancer properties of spices and herbs, especially those used in traditional Asian medicines or cooking. One study has confirmed that spices used to treat gastrointestinal ailments in Thailand inhibited the growth of Helicobacter pylori (or H. pylori) bacteria known to cause gastric cancer.
Subsequent work has shown that ginger and turmeric have similar inhibitory action against H. pylori. Turmeric has also been shown to have anti-inflammatory, anti-angiogenic, and anticancer properties.
Leaving the Dark Ages
A truly “natural” cure–or even treatment–for cancer is unknown. Future approaches, however, will be more targeted and will be based on a robust understanding of how cancer cells work and the interaction of nature-derived, anticancer therapies. “Mother Nature doesn’t make simple compounds…[but] natural products make sense because they work,” observes Dr. David Newman, chief of NCI’s Natural Products Branch (NPB).
By combining the best of scientific methodology with Mother Nature’s chemistry set, patients and researchers can expect to see safer, more effective therapies.