[의학신문·일간보사=이재원 기자] The Korea Institute of Atomic Energy Research (President Jong-hoon Park) confirmed that when Dr. Jae-seong Kim’s research team combined radiation therapy and targeted chemotherapy, it reduced the generation of immunosuppressive cells and confirmed the effect of systemic anti-cancer immunotherapy that removed not only cancer cells in the radiation-treated area but also metastatic cancer. said.
Recently, immunotherapeutic agents such as immune checkpoint inhibitors, which activate the immune system to remove cancer cells, have been used together with radiation therapy. It is gaining popularity as a chemotherapy strategy.
However, immune checkpoint inhibitors are very expensive, and there is no therapeutic response in some cancers, so there is a need to develop new anticancer immunotherapeutic agents that are effective and relatively inexpensive.
The research team focused on improving the effect of chemotherapy by reducing immune-suppressing cells by inhibiting immune cell regulators in previous studies. hypothesized that there would be
Dr. Jae-Seong Kim’s team confirmed that the anti-cancer immunity was activated and the anti-cancer treatment effect was improved through the experiment of combining the newly discovered new drug candidate with radiation therapy.
First, as a result of administering a new drug candidate (BR101801) and radiotherapy in 15 mice transplanted with colon cancer, the tumor growth inhibitory effect was observed, reducing the tumor size to 92.8% in all mice. In mice, complete remission was confirmed in which the tumor completely disappeared.
In addition, a 45.7% increase in killing ability and a 9.9% increase in anticancer-specific immune response, indicating the cancer cell killing ability of key anticancer immune CD8 T lymphocytes that directly destroy cancer cells, were confirmed. The ratio of ‘T/regulatory T lymphocytes’ was maintained at 0.9 when radiotherapy alone, 1.5 when only a new drug candidate (BR101801) was administered, and 4.6 when combined with radiotherapy.
In addition, there was no cancer recurrence by increasing the production of memory T cells, one of the immune cells involved in immune memory.
In particular, in 7 out of 13 mice, local radiation treatment alone demonstrated a systemic anticancer effect along with a growth inhibitory effect that reduced the tumor size to 93.4% in metastatic cancer as well as the tumor site. When transplanted once more, the tumor did not grow for regarding 4 weeks, and the long-term anticancer effect increased and the relapse inhibitory effect was confirmed.
The results of this study, which proved the possibility of developing an anticancer immunotherapeutic agent in combination with radiation, were published in the online edition of ‘Journal for immunotherapy of cancer (IF13.751)’, an international academic journal in the field of tumor immunology, on March 14, 2022. has been published
Dr. Kim Jae-seong said, “This study suggested the possibility of dramatically improving the effects of radiation chemotherapy by confirming the therapeutic effects of not only solid cancers but also metastatic cancers that are difficult to treat. We expect treatment benefits to return to patients with intractable cancer as soon as possible,” he said.