A Japanese research team has found a new way to curb cancer cells in the immune system and are now pushing for a clinical trial following the publication of their research
A research team in Japan has developed a way to curb cancer cells.
The team, led by immunologist Masahiro Yamamoto, developed a series of tests that revealed a way to slow the development of certain T cells that restrain the immune system. Testing on mice during their study, the findings of their experiments were published yesterday (Friday, November 22) and it provides a hopeful next step for cancer cell research.
Professor Yamamoto, of Osaka University’s Research Institute for Microbial Diseases, said: “It may lead to a new immunotherapy that does not trigger autoimmune diseases, so we want to engage in drug discovery.”
Immune functions in the human body mean cancer cells and harmful microbes can be defeated, however stronger immunity can trigger an autoimmune reaction which can then lead to an attack on the body’s own tissue. Cells in the human body are usually balanced between immune cells and cells that halt immunity.
Cancer tissues include more of the latter type which halt the immunity, making it easier for cancer to grow. But Professor Yamamoto and his team found that cancer cells could be neutralised by certain cell types. Inside cancer tissues in mice they discovered a type of regulatory T cell known as Th1-Treg, which uses a substance called PF4 to increase in number.
When administering a neutralizing antibody to inhibit PF4, the team found that Th1-Treg decreases and that cells driving immunity become more active, therefore curbing cancer growth. Cancer patients with high levels of PF4 have lower rates of survival, JapanTimes reported.
Professor Yamamoto and his team concluded that a clinical trial would be necessary to further understand the link between lower survival rates, levels of PF4 and the possible decrease in PF4 activity when introduced to regulatory Th1-Treg cells. He said: “We’ve found a neutralizing antibody against PF4 for humans, and we want to conduct a clinical trial with the support of pharmaceutical companies.”
Th1-Treg is not the only regulatory cell in the human body. Removing all type causes autoimmune diseases, but removing just Th1-Treg is unlikely to cause problems, the team concluded. The team’s study, which has since been published, concluded there was a link between the higher numbers of PF4 and the poorer recovery of their study animals.
It reads: “We identified Arg1+ TAM–secreted PF4 as a key determinant of TH1-Treg cell accumulation in the TME, which suppresses antitumor immunity and promotes tumor growth. Furthermore, PF4 neutralization inhibits TH1-Treg cell polarization and suppresses tumor growth.
“Given that data from The Cancer Genome Atlas suggest that higher numbers of PF4+ TAMs are associated with poorer prognoses in humans, PF4 represents a potential new target for cancer immunotherapy.”
