New anti-cancer weapon: Nanotech

Scientists in Shanghai say they have made a breakthrough in researching an alternative to chemotherapy that would treat tumors in a safe, efficient way with zero side effects for patients.

Chemotherapy has long been used in the treatment of cancer and involves one or a combination of drugs being introduced to the patient's bloodstream to kill cancer cells. Yet it affects healthy cells, too, causing lower immunity to infection, fatigue and hair loss.

On Tuesday, a team from the Shanghai Institute of Ceramics, which is part of the Chinese Academy of Sciences, announced it has devised a therapy using inorganic, nontoxic nanoparticles that can travel around the body and target only tumors, leaving healthy cells unaffected.

"Laboratory testing on mice has shown that tumors shrank by 85 percent after receiving the therapy," said Shi Jianlin, lead researcher at the institute.

For the tests, researchers give two nanoparticles-Fe3O4 and SiO2, the latter being a transport agent-and glucose oxidase through intravenous injection to mice.

The particles target tumor cells owing to special microenvironment of acidity and high glucose content, while the chemical compounds combined will trigger reactions in tumor cells and produce a highly toxic active substance that will kill the cells, Shi said.

He said his team of scientists has also created a nanoparticle called Mg2Si, which is nontoxic in a neutral environment of healthy tissue and only triggers a reaction in the acid environment of a tumor.

"The reaction will consume a large amount of oxygen molecules in the tumor cells and block the vascular system in the tumor cells so as to prevent the supply of oxygen molecules and nutrients from outside. The tumor cells will eventually starve to death," he explained.

Papers on the research were published in Chemical Society Reviews in February, Nature Nanotechnology in December and Nature Communications in August.

"This contribution reports a nice overview of nanoparticle-triggered catalytic chemical reactions for cancer therapy. The authors provide a complete state of the art of the topic emphasizing the different approaches that can be used," reads one peer review in Chemical Society Reviews.

Chen Qinfen, a doctor specializing in hematology at Fudan University's Huashan Hospital in Shanghai, said the new therapy sounds exciting.

"During and after chemotherapy, patients of lymphoma and leukemia will suffer from a decrease in blood platelets or white blood cells, or impairment in the liver, kidney or nervous system. More than half of leukemia patients die of complications after chemotherapy," she said.

"The particular advantage of nanoparticles is that they are small enough to enter the cytoplasm and nucleus, which makes the treatment more precise and efficient."

Shi stressed on Tuesday that the research is still at the stage of lab tests and in the future his team may have to pick the most applicable approach for clinical trials.

"Lab tests also proved that our therapies are able to prevent tumor metastasis. We hope it will also make contributions clinically," he said.