Jan 25, 2021 07:00:00

Development of 'cancer vaccine' that may save humankind from cancer is in progress

Vaccines are medicines that give immunity to infectious diseases by administering antigens made from pathogens. Although it is a little different from vaccines that are effective against viruses that do not respond to antibiotics, such as influenza virus and new coronavirus, there are actually ' cancer vaccines ' that are used to treat cancer . Among such cancer vaccines, research results of cancer vaccines for malignant melanoma, which is a type of skin cancer, have been announced.

Personal neoantigen vaccines induce persistent memory T cell responses and epitope spreading in patients with melanoma | Nature Medicine
https://www.nature.com/articles/s41591-020-01206-4

Cancer vaccine helped keep melanoma under control for years in small study | Live Science
https://www.livescience.com/melanoma-vaccine-small-trial.html

Cancer vaccines are one of the ' immunotherapies ' that kill cancer cells that already exist in the body. Cancer vaccines train immune cells called T cells to recognize and destroy cancer cells lurking in healthy cells in the body with high accuracy.

A research team led by Catherine Wu, a researcher at the Dana-Farber Cancer Institute , is developing a function by training T cells to recognize specific proteins contained in melanoma cells. In 2013, we started Phase I clinical trials for cancer vaccines.

Vaccines for treating skin cancer have started Phase I clinical trials and may be applied to other cancers --GIGAZINE

Eight patients who had surgery for melanoma were vaccinated with the cancer vaccine under study and followed up for four years. This vaccine allows T cells to store a unique protein predicted from RNA obtained from the patient's own cancer cells as a new antigen .

Two of the eight patients had an early recurrence of the cancer, but six had no recurrence of the cancer. Blood samples taken on a regular basis show that T cells continue to remember the targeted proteins for at least four years after cancer vaccination. In addition, the researchers report that over time after cancer vaccination, they also became aware of other proteins associated with melanoma.

According to Mr. Wu, T cells that have memorized the target protein by the cancer vaccine will attack the cancer cells of melanoma and then examine the information contained in the attacked cancer cells. As T cells gather more information in preparation for future attacks, they will be able to recognize antigens that were not in the original cancer vaccine.

In addition, two patients with recurrent cancer were given

immune checkpoint inhibitors because the cancer had spread to the lungs. The researchers then reported that the administration of both a cancer vaccine and an immune checkpoint inhibitor eliminated detectable cancer in both patients.

Immune checkpoint inhibitors were originally approved in 2011 for the treatment of melanoma. Our body is equipped with a system that suppresses the proliferation and function of T cells, which are immune cells, so that the immune system does not run out of control. Cancer cells use this suppression system to signal that they suppress the movement of T cells and escape attack. Immune checkpoint inhibitors enhance the immune response to cancer cells by releasing the brakes on these T cells.

'It's pretty rare to see a complete response early in the treatment period,' said Patrick Ott of the Dana-Farber Cancer Institute, who led the study with Wu. In the case of two patients, the cancer vaccine It's a sign that it's working with immune checkpoint inhibitors to increase efficacy. '

The research team rates the study as very promising, but with only eight subjects, it has not shown the effectiveness of the cancer vaccine and will conduct more trials. It states that it is necessary.