Targeted therapy is a form of cancer treatment that employs medicines that are specifically intended to kill cancer cells while leaving healthy cells alone.
Cancer cells contain mutations in their genes that distinguish them from normal ones. Genes are instructions written in a cell’s DNA that inform it what to do. When a cell’s genes are altered, it stops acting like a normal cell. Gene alterations in cancer cells, for example, may help the cell to grow and divide rapidly. These alterations are what distinguishes it as a cancer cell.
However, there are several kinds of cancer, and not all cancer cells are alike. Colon cancer and breast cancer cells, for example, have distinct gene alterations that aid their growth and/or spread. Even among persons with the same basic kind of cancer (such as colon cancer), cancer cells might have distinct gene alterations, causing one person’s colon cancer to be different from another’s.
Researchers have also discovered that the environment in which malignancies begin, develop, and thrive differs from one cancer to the next. Some tumors, for example, include proteins or enzymes that convey instructions to the cancer cell telling it to grow and duplicate itself.
Knowing these features has led to the creation of medicines that can “target” these proteins or enzymes and prevent them from sending messages. Targeted medicines can either block or turn off the signals that cause cancer cells to proliferate, or they can signal cancer cells to die.
Targeted therapy is an essential kind of cancer treatment, and as scientists understand more about particular alterations in cancer cells, more targeted medicines will be developed. However, only a few types of malignancies are now treated exclusively with these medicines. Surgery, chemotherapy, radiation treatment, or hormone therapy are all common side effects of targeted therapy.
What distinguishes targeted treatment from chemotherapy?
Targeted therapy medicines, like other cancer-fighting therapies, are classified as chemotherapy. Targeted treatment medicines, on the other hand, are not the same as typical or standard chemotherapy (chemo). Targeted medicines target some of the differences that distinguish cancer cells from normal ones. This distinguishes them from chemotherapy in two major ways:
- These medicines have an effect on cancer cells but usually leave normal, healthy cells alone due to their focused activity. Traditional chemotherapy is cytotoxic to most cells, which means that it can harm normal, healthy cells as well as malignant cells.
- Targeted medicines frequently operate by preventing cancer cells from replicating. They can assist a cancer cell stops dividing and producing new cancer cells in this way. Chemotherapy, on the other hand, destroys cancer cells that have already formed.
What is the mechanism of targeted therapy?
Targeted treatments can identify and inhibit particular types of instructions transmitted inside a cancer cell that tell it to grow, or can discover and attack specific regions or chemicals in cancer cells. The following are some of the chemicals found in cancer cells that become “targets” for targeted therapies:
- On a cancer cell, there is too much of a specific protein.
- A cancer cell’s protein that isn’t found in normal cells.
- On a cancer cell, a protein has been mutated (changed) in some manner.
- Gene (DNA) alterations do not occur in a healthy cell.
Targeted medicines have the ability to:
- Chemical signals that tell the cancer cell to grow and divide are blocked or turned off.
- Stop creating new blood vessels to feed the cancer cells via changing proteins within the cancer cells.
- Your immune system will be triggered to kill the cancer cells.
- Toxins are sent to cancer cells to destroy them, but not to normal ones.
The way medicines operate and the adverse effects they produce might be affected by their activity.
It’s worth noting that some targeted treatment medicines, such as monoclonal antibodies, regulate cancer cells in several ways and may potentially qualify as immunotherapy since they enhance the immune system.
Precision medicine as targeted therapy
Precision medicine or customized medicine are terms used to describe targeted therapy. This is due to the fact that they are designed to precisely target certain alterations or chemicals in cancer cells, and these targets might differ even across persons with the same cancer type.
Following a biopsy or surgery, some types of tumors are examined for distinct targets, which can aid in determining the most successful treatment. Finding a specific target allows for more accurate or tailored therapy matching.
Some targeted medicines have a higher level of “targeting” than others. Small and big molecule medicines are the two types of targeted treatments.
- Once found, small molecule medicines are small enough to enter a cancer cell. They operate by identifying and inhibiting a particular chemical within the cell.
- Large molecular medicines are typically too large to fit inside a cell. They act by attacking proteins or enzymes on the cell’s surface, weakening or killing them. They’re commonly referred to as a “lock and key” since the molecule acts as a key, unlocking the enzyme or protein on the cell’s surface. The medication works because the key fits inside the lock.
Targeted treatment comes in several forms.
Targeted treatments can be used to treat a variety of cancers, and there are many distinct forms of targeted medicines. Here are a few samples of each kind and how they’re utilized.
- Angiogenesis inhibitors prevent new blood vessels from forming, which feed and nourish cancer cells. Bevacizumab, for example (many different cancers).
- Monoclonal antibodies can transport chemicals on their own or in combination with medicines into or onto cancer cells to destroy them. Alemtuzumab (for some chronic leukemias), trastuzumab (for certain breast malignancies), and cetuximab (for certain leukemias) (certain colorectal, lung, head and neck cancers). NOTE: Some monoclonal antibodies are referred to as targeted treatment because they attempt to locate, attach to, and assault a specific target on a cancer cell.
- Other monoclonal antibodies, on the other hand, operate as immunotherapy by improving the immune system’s response, allowing the body to more efficiently locate and destroy cancer cells.
- Proteasome inhibitors cause cancer cells to perish by disrupting normal cell processes. Bortezomib is a good example (multiple myeloma)
Signal transduction inhibitors: These interrupt cell signals, causing the cancer cell’s behavior to alter. Imatinib is a good example (certain chronic leukemias)
