Despite being witnessed for over 5,000 years, a definitive cure for cancer remains elusive. Cancer, as described by the World Health Organization, is "a large group of diseases that can start in almost any organ or tissue of the body when abnormal cells grow uncontrollably, go beyond their usual boundaries to invade adjoining parts of the body, and/or spread to other organs." Alarmingly, about 1 in 5 people are at risk of developing cancer in their lifetime, and with incidence rates rising, global concern continues to mount. However, several treatments have shown promising results, with immunotherapy standing out as a particularly effective approach against cancer.
Introduction to immunotherapy:
Your immune system plays a key role in protecting your body from intruders such as allergens and viruses, which it does with the help of special cells that constantly patrol your body for intruders. This leads to the destruction of any damaged or cancerous cell detected, preventing the cancerous tumor from growing and spreading. However, cancer is a moving target, constantly looking for ways to dodge immune system defenses.
Immunotherapy therefore works on first training your immune system so it can do more to find and kill cancer cells, and secondly, helping your body produce cancer-fighting immune cells that effectively locate and destroy cancer cells.
Types of Immunotherapy:
Checkpoint inhibtors: Within a human body, multiple checkpoints are present to keep your immune system from overreacting to intruders and damaging healthy cells. They are responsible for managing the flow of signals to T-cells and telling the cells when to turn off and on. T-cells turn on to kill cancerous cells. As immunotherapy drugs, they work by breaking the connection between the checkpoint proteins and other proteins. Breaking the connection keeps protein cells from telling T cells to turn off. That way, T-cells keep on killing cancerous cells. These checkpoint inhibitors are helpful in treating advanced cancer that can’t be treated with surgery or cancer that hasn’t responded to other treatments.
CAR T-Cell Therapy: Chimeric antigen receptor (CAR) T-cell therapy works by turning your T lymphocytes, or T-cells, into more efficient cancer-fighting machines. When your T-cell security team senses intruder antigens, they use their receptors to catch and block the intruders. More than that, your T-cells can kill the intruders. But antigens have their own form of protection. They can disguise themselves to hide from your T-cells. CAR T-cell therapy ensures your T-cells aren’t fooled by antigens in disguise. This therapy helps in the treatment of certain blood cancers, breast cancer, and brain cancer.
Cancer Vaccines: Vaccines that protect against cancer work by helping your immune system identify antigens in cancerous cells. Just like other kinds of vaccines, cancer vaccines use all or part of cancerous cells to help your body identify a harmful tumor in your body. Cancer vaccines don’t prevent cancer. But if you develop cancer, cancer vaccines train your body to fight it.
Recent breakthroughs:
A new immunotherapy drug has just been discovered to have significant effects on people suffering from aggressive skin cancer. An international research team has demonstrated a method to identify the cells in the immune system that can recognize and fight cancer cells in samples from 9 out of 10 patients affected by the rare but aggressive form of skin cancer, Merkel cell carcinoma. The results of the research have been published in The Journal of Clinical Investigation and may eventually open up new forms of immunotherapy in the treatment of people with Merkel cell cancer.
Another study identified that combining JAK inhibitors with checkpoint inhibitors improves cancer immunotherapy response. In two independent clinical studies, researchers investigated whether using JAK inhibitors or jakinibs, which prevent inflammation from inside cells, could improve the antitumor responses of anti-PD-1 ICI immunotherapy in cancer patients. Divij Mathew and colleagues conducted a phase II clinical trial to investigate the use of the JAK1 inhibitor itacitinib in combination with the anti-PD-1 ICI pembrolizumab as a first-line treatment for metastatic non-small cell lung cancer (NSCLC). Mathew et al. found that delayed administration of itacitinib following treatment with pembrolizumab improved the response to immunotherapy. According to the findings of the trial, which included 21 patients with treatment-naïve NSCLC, median progression-free survival was nearly 2 years, compared to the 6.5 to 10.3 months reported in other trials with only ICI.
Patient Impact:
Originally diagnosed with uterine cancer, Irisaida was dismayed when, after 11 months of remission, her doctors informed her that the cancer had metastasized to her lungs. She was now considered a Stage IV cancer patient and was advised to receive a lobectomy, followed by a standard course of chemotherapy. After completing 6.5 hours of chemotherapy, it became obvious that something else needed to be done. Despite the aggressive treatment, the cancer had continued to spread and was now attacking the upper lobe, the pleura, and the mediastinum, completely compromising Irisaida’s ability to breathe. “That is when I started seeking other options,” she said. Irisaida consulted other doctors, and it was agreed upon that, because she had the PDL-1 immune inhibitor, she would qualify for an immunotherapy trial. “I had no other choice; the chemo wasn’t working, and without treatment, my doctors only gave me 18–24 months to live,” she explained. Six months into the treatment, her cancer began to shrink, and now, two years later, there is no evidence of disease.
Another cancer victim, Alison, 61, was diagnosed with advanced non-small cell lung cancer in 2018. After four years of treatment on a combination therapy of immunotherapy and chemotherapy, she has no cancer on her scans.
Similar to both of them, Abi Richards was just 27 years old when she was given the devastating news that she had cancer. Scans had revealed 13 tumors in her liver and two in her lung. If the diagnosis wasn’t bad enough, Abi was told she had just two weeks to live.
With time running out, our doctors recommended trying cancer immunotherapy, making it clear that although the treatment might work, there was a risk that it could also speed up the progression of the disease. Miraculously, within six months, the tumors had shrunk, and no active cancer cells were detected. It was one of the most remarkable cases Southampton doctors had seen and demonstrated the amazing power of immunotherapy.
These remarkable stories of cancer survivors just further prove the pivotal role immunotherapy has played in combating cancer.
Future Directions:
From finding new ways to galvanize the immune system to developing new immunotherapy drugs, we're working to get new, effective treatments to patients. In London, Dr. Masahiro Ono is looking at the roles played by our immune cells in response to melanoma, the most common type of skin cancer. He's exploring ways to activate immune cells to see if he can make immunotherapy more successful at treating cancer and reduce the side effects. Like him multiple others are also involved in similar research initiaves.
With such research and investigations continuing, a cure for cancer is not far away!
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Assessed and Endorsed by the MedReport Medical Review Board