2021 Cancer Treatment: In addition to traditional surgery, radiotherapy and chemotherapy, our weapons against cancer include new approaches such as antibody-coupled drugs, tumor vaccines, immune checkpoint monoclonal antibodies, pericyte immunotherapy, and hormone therapy.
Traditional treatments for cancer, such as surgery, radiation therapy and drug therapy, have certain limitations. With the development of tumor genomics, bioimmunotherapy has become the fourth means of tumor treatment.
Studies have proved that tumor cells have tumor antigens and the immune system can distinguish tumor cells from normal cells by recognizing tumor antigens.
Tumor vaccines can activate or strengthen the body’s own anti-tumor immunity by expressing specific, immunogenic tumor antigens (e.g., peptides, DNA and RNA), with the aid of adjuvants such as cytokines and chemokines, and then kill and remove tumor cells. Currently, the most well-known tumor vaccine is the cervical cancer vaccine.
Immune checkpoint inhibitors
Patients often refer to PD-1 monoclonal antibody as “immunotherapy”, but in fact, “immunotherapy” is a large category of cancer treatment, and “immune checkpoint inhibitor” is an important component. PD-1 monoclonal antibody is only one kind of immune checkpoint inhibitor.
There is a big difference between immune checkpoint inhibitors and traditional anti-tumor therapies: traditional anti-tumor therapies, such as radiotherapy and chemotherapy, directly kill tumor cells, similar to dropping bombs in warfare, while immune checkpoint therapy specifically activates the patient’s own immune cells, equivalent to making soldiers and weapons more powerful in warfare.
In 2018, two scientists, James Allison from the University of Texas and Masayuki Motosu from Kyoto University in Japan, were awarded the Nobel Prize in Medicine and Physiology for “the discovery of novel cancer therapies that inhibit negative immune regulation”.
Currently, “immunotherapy” is effective for only a few types of cancer, and if patients respond to “immunotherapy”, they will continue to benefit from it without the resistance common to chemotherapy and targeted drugs, and the lucky ones can even be “cured”. The scientific community believes that “immunotherapy” is an effective treatment for a small number of cancers. The scientific community believes that “immunotherapy” will be the future of cancer treatment.
Antibody-drug couples (ADCs) are small molecules of biologically active drugs attached to a single antibody through a chemical link, and the single antibody acts as a carrier for the targeted transport of the small molecule into the target cell.
Research on antibody-coupled drugs dates back to the 1980s, but it was not until 2000 that the first antibody-coupled drug was approved by the FDA for the treatment of acute granulocytic leukemia. The drug was withdrawn from the market in 2010 because of safety concerns.
In 2011, Takeda/SeattleGenetics improved the original technology and developed a new antibody-coupled drug, SGN-35, which was approved by the FDA in 2011 for the treatment of Hodgkin’s lymphoma and systemic mesenchymal large cell lymphoma. 2013 saw another breakthrough in antibody-coupled drugs, with the FDA approval of T-DM1 for HER2-positive breast cancer. breast cancer, the first antibody-coupled drug to target a solid tumor.
With the successful development of these two drugs, ADC drugs are once again entering the research landscape with a blaze of enthusiasm.
Relay immune cell therapy
Relay immunity is a kind of tumor biotherapy, which refers to the isolation of tumor-infiltrating lymphocytes (TIL) or peripheral blood lymphocytes from tumor patients, sorting, expansion, activation and transfusion back to patients in vitro, so that they can acquire anti-tumor immunity.
The famous CAR-T therapy is a kind of transitional immune cell therapy, and eight years ago, a young girl with acute lymphoid leukemia became the first child in the world to receive experimental CAR-T cell immunotherapy when Emily’s life was in danger. Post-treatment tests showed that the cancer cells in her body had completely disappeared, and to this day there is no sign of recurrence.
Every year, Emily tells the world: she is well and cancer-free.
Hormone therapy, which should be called hormone blocking therapy to be exact, is a treatment for cancer by blocking the effect of hormones that promote cancer growth. In some cancers, human hormones promote tumor growth by binding to receptor proteins on the outer surface of cancer cells. Therapies that inhibit cancer cells by blocking hormones are commonly used for breast, gynecologic and prostate cancers. In addition, certain hormones, such as corticosteroids, have a general anti-proliferative effect due to their ability to downregulate genes and induce apoptosis. As with chemotherapy and targeted therapies, hormone therapy can be used to control malignancies at various time points, including neoadjuvant, adjuvant and metastatic phases.
Amino acid imbalance therapy
Traditional cancer therapies include chemotherapy and radiotherapy, but this often has side effects. An emerging cancer treatment strategy is to “starve” cancer cells, causing them to die. Treatments that “starve” cancer cells are often mild, taking advantage of the different metabolic needs of normal and tumor cells. A drug in development, ADI-PEG 20, for example, destroys arginine in the bloodstream, thereby blocking the growth of cancer cells and specifically killing them.