Cancer is one of the highest causes of death in the world. The World Health Organization (WHO) recorded 10 million cases of cancer diagnosed in the year 200 and increased to 14 million cases in 2012 – 8.2 million of whom died from cancer.
WHO estimates the number of cancer patients globally will rise to 19 million people in 2025. The increasing number of cases of cancer makes the researchers continue to develop various ways in the treatment of cancer.
One way to treat and increase the life expectancy of cancer patients is with the cancer vaccine. Indeed, how does it work?
Overview of cancer vaccine
In principle, a cancer vaccine is similar to a vaccine used against other diseases.
Vaccines work by training the immune system to recognise and combat pathogens, either viruses or bacteria.
To do this, certain molecules of the pathogen must be inserted into the body to trigger an immune response, called the antigen.
By injecting antigens into the body through vaccination, the immune system can recognise the pathogen causing the disease by producing antibodies.
It is these antibodies that will fight pathogens before they spread and cause disease. The antibodies will also recognise the pathogen of the disease if it reappears later.
The difference is for cancer vaccine, the vaccine maker component is not from virus or bacteria that have been turned off. Both do not cause cancer.
Therefore, the components of the cancer vaccine maker will be tailored to each patient’s condition and given when the cancer has emerged, not aiming for prevention.
How does a cancer vaccine work?
Every cancer treatment aims to destroy cancer cells and keep healthy cells alive.
Cancer vaccines are “charged” by components containing specific molecules that are only present in cancer cells, so the vaccine can help the immune system recognise malignant cells and instruct immune cells to seek and destroy cancer cells.
Researchers start by sequencing the genes that encode proteins in a patient’s tumour called neoantigen. Then they use a computer to predict which neoantigen is best known for immune cells.
Furthermore, the scientists provided vaccines containing up to 20 specific and different neoantigen for each patient’s cancer.
How much chance can a cancer vaccine cure cancer?
Cancer vaccines aimed at helping patients fight cancer cells appear promising in two new studies.
One study led by Dr Catherine Wu, a scientist at Dana-Farber Cancer Institute, Boston, vaccinated six skin cancer melanoma patients, who had previously performed surgical removal procedures for tumours.
They make a specific vaccine for each patient and inject it under the skin of the patient regularly for five months. They found that as many as four patients showed no signs of recurrence after 25 months.
Although two other patients have relapsed, they can be completely cured after additional therapy is a PD-1 inhibitor that can generate the immune system.
Similar results came from other experiments by Dr Ugur Sahin from Johannes Gutenberg University, Germany. They experimented on 13 patients with melanoma, which had previously removed the tumour.
They injected a vaccine containing up to 10 neoantigens into the patient’s lymph nodes and found eight patients of whom did not recur after 23 months.
One of the five patients who had recurrence was also able to recover completely after PD-1 inhibitor was administered.
Is the cancer vaccine widely available?
Not yet. Although the personalised cancer vaccine has been shown to trigger an immune response in the human body to fight cancer cells, the results of this study are still on a small scale.
Researchers continue to develop larger-scale trials and are excited to combine cancer vaccines with PD-1 inhibitor drugs.
The researchers believe that the personalised vaccine is an excellent solution for cancer treatment.