A team of researchers in Japan has pinpointed how cancer cells spread throughout the body, a finding that could lead to the development of a new treatment medicine.
The scientists, primarily from Kyoto University and Nagoya University, said that cells within carcinoma tissue are apt to flee from “hot spots” that contain high levels of a reactive oxygen species called hydrogen peroxide.
The team said cancer cells partially detach and disperse from these hot spots, marking the beginning of carcinoma metastasis. Tumors then migrate from their original locations to other organs and tissues, much to the dismay of doctors and patients.
Shedding light on this troublesome yet poorly understood phenomenon through a mouse experiment, the findings have been published in the British scientific journal Nature Cell Biology.
“Introducing an environment where cancer cells do not need to escape may help prevent tumor metastasis,” said Nobuaki Takahashi, an associate professor of medical chemistry at Kyoto University.
Many living creatures, including humanity, utilize oxygen to obtain energy. Reactive oxygen species are produced in the body in this process.
Accumulated reactive oxygen species cause oxidative stress and damage to cells. In this light, reactive oxygen species can be considered toxic to cells in most cases.
The research team tested their developed method to directly detect reactive oxygen species around individual cells, so the cancer tissue in mice with transplanted human tumor cells could be examined closely.
The results revealed that hydrogen peroxide was distributed unevenly to bring on hot spots characterized by locally high concentration levels. Cells exposed to such elevated-density areas frequently separate and release themselves from carcinoma tissue.
This phenomenon was confirmed and corroborated through another analysis on a relevant genetic function, too.
Meanwhile, the team discovered that the formation of areas with high concentrations of hydrogen peroxide was hindered if a type of immune cell called the neutrophil was eliminated from cancer tissue. Neutrophils were spotted en masse around hot spots.
Given all that, the researchers concluded that accumulated neutrophils around cancer tissue generate hydrogen peroxide and thereby hot spots. When exposed to high concentrations of hydrogen peroxide, cancer cells detach and migrate away from tumor tissue as if escaping from the harmful substance.
They suggested that this system likely explains the initiation of tumor metastasis.
Based on the lately ascertained mechanism, the team is advancing the research and development of a medicine to inhibit cancer metastasis by specifically removing the reactive oxygen species that facilitates the separation and release of tumor cells.