Researchers Find New Path to Control Tumor Growth
New evidence by University of Alabama at Birmingham researchers that specific electromagnetic fields can safely block the proliferation of cancer cells and tumor growth may help refine a new, targeted therapy without any collateral damage.
Very low levels of amplitude-modulated radiofrequency electromagnetic fields block cancer-cell growth in a tumor- and tissue-specific fashion, says Boris Pasche, M.D., Ph.D., director of the UAB Division of Hematology and Oncology. Pasche and a research team led by Jacquelyn Zimmerman, graduate student in the UAB Medical Scientist Training Program, conducted studies with cancer cells, replicating the treatment conditions in patients with cancer. The results were published in the Dec.1, 2011, online version of the British Journal of Cancer.
The study provides the first laboratory evidence of an effect observed in earlier clinical studies when cancer cells, exposed to electromagnetic fields emitted by custom-made devices replicating patient-treatment conditions, was found to be blocked by specific modulation frequencies. The new study suggests that fine-tuning field frequency makes the effect specific to certain tissues and tumors and holds clues for how it might work.
Two earlier clinical studies suggested the growth of cancer cells may be altered following exposure to specific frequencies; however, this is the first time an effect has been observed in a laboratory setting, Pasche says.
“We now have laboratory evidence showing a direct effect on cancer cells and providing a plausible mechanism of action based on the modulation frequencies used in patients,” says Pasche. In recent studies, Pasche and his team gathered clinical evidence that very low and safe levels of amplitude-modulated electromagnetic fields may elicit therapeutic responses in patients with advanced liver and breast cancer. “However, until now there was no known mechanism explaining how very low levels of electromagnetic fields might block the growth of cancer cells while sparing healthy cells” says Pasche.
Zimmerman says, “It is exciting to identify an effect targeting only tumor cells with limited side-effects for patients. As a graduate student, it is a thrill to see translational research in action.”
Marijuana Cuts Tumor Growth by 50%
The active ingredient in marijuana cuts tumor growth in common lung cancer in half and significantly reduces the ability of the cancer to spread, say researchers at Harvard University who tested the chemical in both lab and mouse studies.
They say this is the first set of experiments to show that the compound, Delta-tetrahydrocannabinol (THC), inhibits EGF-induced growth and migration in epidermal growth factor receptor (EGFR) expressing non-small cell lung cancer cell lines. Lung cancers that over-express EGFR are usually highly aggressive and resistant to chemotherapy.
THC that targets cannabinoid receptors CB1 and CB2 is similar in function to endocannabinoids, which are cannabinoids that are naturally produced in the body and activate these receptors. The researchers suggest that THC or other designer agents that activate these receptors might be used in a targeted fashion to treat lung cancer.
“The beauty of this study is that we are showing that a substance of abuse, if used prudently, may offer a new road to therapy against lung cancer,” said Anju Preet, Ph.D., a researcher in the Division of Experimental Medicine.
An in vitro system replicating patient-treatment conditions, designed and constructed by Ivan Brezovich, Ph.D., professor and director of radiation physics in the UAB Department of Radiation Oncology, enabled scientists to examine cancer cells in the laboratory that were exposed to tumor-specific modulation frequencies. They discovered that very low levels of radiofrequency electromagnetic fields, which are comparable to the levels administered to patients, significantly inhibited tumor-cell growth.
To determine how such frequencies impede cancer-cell growth, the team collaborated with Devin Absher, Ph.D., and Rick Myers, Ph.D., from Hudson-Alpha Institute for Biotechnology. The scientists observed the anti-proliferative effect is mediated by changes in gene expression and by disrupting dividing cells.
Broccoli May Help Fight Cancer Growth
Broccoli may help fight cancer by blocking a defective gene associated with tumor growth, according to new research.
Previous studies have heralded the potential cancer-fighting ability of broccoli and other cruciferous vegetables such as cauliflower and watercress. But researchers say until now they didn’t know the secret behind the vegetables’ anticancer attributes.
In a new study, researchers found compounds in broccoli and other cruciferous vegetables called isothiocyanates (ITCs) appear to target and block mutant p53 genes associated with cancer growth.
Gene p53 is known as a tumor suppressor gene and appears to play a critical role in keeping cells healthy and protecting them from cancer. When this gene is damaged or mutated, it stops offering this protection. Researchers say these mutations are found in about half of all human cancers.
In a report published in the Journal of Medicinal Chemistry, researcher Xiantao Wang of Georgetown University and colleagues analyzed the effects of ITCs on gene p53 in a variety of human cancer cells, including lung, breast, and colon cancer, in the lab.
The results showed that ITCs were capable of removing the defective p53 gene while leaving healthy versions of the gene alone.
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By Jennifer Warner
WebMD Health News
“This is the first experimental evidence that electromagnetic fields can both down-regulate the expression of genes that control cell migration and affect the mitotic spindle,” says Pasche. “Part of the framework that guides cells as they divide and multiply, mitotic spindles are essential to normal tissue growth and to the fast, abnormal growth seen in cancer. Interfering with them only in cancer cells is an exciting prospect.”
“These findings uncover a new alley to control tumor growth and may have broad implications for cancer treatment,” Pasche says. “We hope these findings help develop and refine a new safe, targeted therapy to kill cancer cells without any collateral damage.”
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Source: University of Alabama at Birmingham