Tumours

Exercise boosts tumour-fighting ability of chemotherapy

Study after study has proven it true: exercise is good for you. But new research from University of Pennsylvania scientists suggests that exercise may have an added benefit for cancer patients undergoing chemotherapy.

Exercise boosts tumour-fighting ability of chemotherapy

Their work, performed in a mouse model of melanoma, found that combining exercise with chemotherapy shrunk tumors more than chemotherapy alone.
Joseph Libonati, an associate professor in the School of Nursing and director of the Laboratory of Innovative and Translational Nursing Research, was the senior author on the study, which appears in the American Journal of Physiology. His collaborators included Penn Nursing’s Geetha Muthukumaran, Dennis Ding and Akinyemi Bajulaiye plus Kathleen Sturgeon, Keri Schadler, Nicholas J. Thomas, Victor Ferrari and Sandra Ryeom of Penn’s Perelman School of Medicine.

Exercise has long been recommended to cancer patients for its physical and psychological benefits. Libonati and colleagues were particularly interested in testing whether exercise could protect against the negative cardiac-related side effects of the common cancer drug doxorubicin. Though effective at treating a variety of types of cancer, doxorubicin has is known to damage heart cells, which could lead to heart failure in the long-term.

“The immediate concern for these patients is, of course, the cancer, and they’ll do whatever it takes to get rid of it,” Libonati said. “But then when you get over that hump you have to deal with the long-term elevated risk of cardiovascular disease.”

Previous studies had shown that an exercise regime prior to receiving chemotherapy could protect heart cells from the toxic effects of doxorubicin, but few had looked to see whether an exercise regimen during chemotherapy could be beneficial.

To do so, Libonati’s team set up an experiment with four groups of mice. All were given an injection of melanoma cells in the scruffs of their neck. During the next two weeks, two of the groups received doxorubicin in two doses while the other two groups received placebo injections. Mice in one of the treated groups and one of the placebo groups were put on exercise regimens, walking 45 minutes five days a week on mouse-sized treadmills, while the rest of the mice remained sedentary.

After the two-week trial, the researchers examined the animals’ hearts using echocardiogram and tissue analysis. As expected, doxorubicin was found to reduce the heart’s function and size and increased fibrosis — a damaging thickening of tissue. Mice that exercised were not protected from this damage.

“We looked, and the exercise didn’t do anything to the heart — it didn’t worsen it, it didn’t help it,” Libonati said. “But the tumor data — I find them actually amazing.”

The “amazing” result was that the mice that both received chemotherapy and exercised had significantly smaller tumors after two weeks than mice that only received doxorubicin.

Further studies will investigate exactly how exercise enhances the effect of doxorubicin, but the Penn team believes it could be in part because exercise increases blood flow to the tumor, bringing with it more of the drug in the bloodstream.

“If exercise helps in this way, you could potentially use a smaller dose of the drug and get fewer side effects,” Libonati said.

Gaining a clearer understanding of the many ways that exercise affects various systems of the body could also pave the way for developing drugs that mimic the effects of exercise.

“People don’t take a drug and then sit down all day,” Libonati says. “Something as simple as moving affects how drugs are metabolized. We’re only just beginning to understand the complexities.”

Source: science daily

Scorpion’s venom can make cancer cells ‘glow’

Scorpion’s venom can make cancer cells ‘glow’

In what can alter the course of cancer treatment in the near future, researchers have found a compound that appears to pinpoint all of the malignant cells in a patient’s body. The twist is that the compound’s main ingredient is a molecule that is found in the sting of a deadly scorpion. The compound called chlorotoxin is found in the venom of the death stalker scorpion known as leiurus quinquestriatus. It gives malignant cells a bright fluorescent sheen so surgeons can easily spot them, wired.com reported.

‘A scorpion-venom concoction that makes tumours glow sounded almost too outlandish to be true in the beginning. But with generous donations from individuals, the fluorescent scorpion toxin is now in Phase I clinical trials,’ informed Jim Olson from the renowned Seattle-based Fred Hutchinson Cancer Research Centre that developed the technique, called ‘Tumour Paint’. (Read: Cancer vaccine developed to boost lifespan of patients)

Scorpion venoms are cocktails of numerous individual toxins that attack different targets within a victim’s body. Olson and his team found that chlorotoxin did not attach just to brain tumours — it grabbed onto all sorts of cancers, from those that affect the skin to those that destroy the lungs. In lab experiments, Olson began to inject fluorescent-tipped chlorotoxin into mice — the compound lit up cancer cells that no other technology could identify. In one instance, the chlorotoxin illuminated a clump of just 200 malignant cells that were burrowed deep within a wad of fat. ‘That was the point we learned that the technology was far more sensitive than an MRI,’ Olson was quoted as saying

Source: the health site

Gene linked to deadly breast cancer found

Scientists from Weill Cornell Medical College and Houston Methodist have found that a gene previously unassociated with breast cancer plays a pivotal role in the growth and progression of the triple negative form of the disease.

Their research suggests that targeting the gene may be a new approach to treating the disease.

About 42,000 new cases of triple negative breast cancer (TNBC) are diagnosed in the United States each year, about 20 percent of all breast cancer diagnoses. Patients typically relapse within one to three years of being treated.

Senior author Dr. Laurie H. Glimcher, the Stephen and Suzanne Weiss Dean of Weill Cornell Medical College, wanted to know whether the gene – already understood from her prior work to be a critical regulator of immune and metabolic functions – was important to cancer’s ability to adapt and thrive in the oxygen- and nutrient-deprived environments inside of tumors.

Using cells taken from patients’ tumors and transplanted into mice, Dr. Glimcher’s team found that the gene, XBP1, is especially active in triple negative breast cancer, particularly in the progression of malignant cells and their resurgence after treatment.

“Patients with the triple negative form of breast cancer are those who most desperately need new approaches to treat their disease,” Dr. Glimcher, who is also a professor of medicine at Weill Cornell said.

“This pathway was activated in about two-thirds of patients with this type of breast cancer. Now that we better understand how this gene helps tumors proliferate and then return after a patient’s initial treatment, we believe we can develop more effective therapies to shrink their growth and delay relapse,” the researcher added.

The study is published in the journal Nature.

Source: yahoo news