What happens to cancer cells when they die?

Cancer cells are cells that constantly divide, forming solid tumors or flooding blood or lymph with abnormal cells. Cell division is a natural process that the body uses for growth and repair. The mother cell divides to form two daughter cells, and these daughter cells are used to build new tissue or to replace cells that have died due to aging or damage. Healthy cells stop dividing when no more newborn cells are needed, but cancer cells continue to produce copies of them. It is also able to spread from one part of the body to another and multiply there uncontrollably, so we call it a malignant tumor.

Classification of cancer cells

There are different classes of cancer cells, determined according to the type of cell from which they originate.

Carcinoma: The majority of cancer cells are epithelial in origin, starting in the tissues that line the inner or outer surfaces of the body.

Leukemia: It originates in the tissues responsible for the production of new blood cells, most commonly in the bone marrow.

Lymphoma: Lymphoma and myeloma, derived from cells of the immune system.

Ttessarcoma: It originates in connective tissues, including fat, muscle and bones.

Cancer of the central nervous system: derived from brain and spinal cord cells.                                                                   Mesothelioma: which originates in mesothelioma, which is the lining of the body cavities.

Cancer treatments aim to kill cancer cells, and the immune system is tasked with getting rid of the resulting cellular bodies.

What happens to cancer cells after being killed by treatment

Cancer treatments, such as chemotherapy, kill cancer cells, often by pushing them to self-destruct, wilting and dying quietly, or less commonly, by triggering a more explosive form of cell death.

But what happens to cancer cells after they die? Normally, killed cancer cells are recycled in the same way as any other dead cell in the body. When cancer cells end, their outer membranes are usually compromised. This occurs in the "quiet" form of cell death, called apoptosis, a programmed process used to remove unnecessary or damaged cells from the body. Once the molecular keys that lead to apoptosis are triggered, the dying cell shrinks and parts of its membrane separate into "bubbles." This causes the internal components of the cells to leak and attract phagocytes, which are immune cells responsible for devouring cellular debris.

The summoned phagocytes swallow the dead cancer cells and then break them down into smaller components, such as sugars and nucleic acids, which are the chain-like molecules found in DNA. Through this process, the dead cancer cells are recycled into components that can later be reused by other cells.

In the case of apoptosis – a type of cell death cancer treatments that have traditionally been designed to induce the recycling of parts of cancer cells which generally occurs this way rather than being excreted by the body, in the urine, for example. Cancer treatments can sometimes also lead to other types of cell death, such as cell necrosis, the "explosive" form of cell death in which cancer cells swell and explode instead of shrinking. Phagocytes also efficiently devour this type of dead cell However, dying cancer cells do not always pass quietly. Studies show that by releasing numerous debris that triggers an inflammatory reaction, cells can sometimes promote the growth of cancer cells that survive nearby. This phenomenon, known as the Révész effect, may help explain how some cancers return after treatment. It was first observed in the fifties of the last century in mice with tumors.

Studies & Research

More recently, a 2018 study in mice and cells in lab dishes found that radiation and chemotherapy can trigger the release of inflammatory cytokines, molecules released by immune cells that trigger the inflammatory reaction and can sometimes support tumor growth. Immune cells known as phagocytes devour dying cancer cells and then recycle them. Dr. Deepak Panegrahi, co-author of the study and assistant professor of pathology at Beth Deaconess Medical Center in Boston, told Live Science that macrophages, a type of phagocyte, release these molecules in an attempt to fight cancer.

A 2023 study in mice by a different group found that control centers, or nuclei of dying cancer cells, can swell and sometimes explode, thereby ejecting DNA and other molecules into their surroundings. These spilled particles can accelerate the spread of malignancy, meaning cancer cells spread far beyond their original tumor. These studies help shed light on how cancer cell death contributes to cancer development and relapse. However, the research is still in its relatively early stages, and scientists have not yet understood the full implications of this link. With more research, researchers aim to better understand the biological mechanisms underlying cancer and thus develop more effective treatments for the disease. For example, a 2018 study highlighted a way to counteract tumor growth caused by dead cancer cell debris: omega-3-derived molecules that can help reduce inflammation and cytokine effects while stimulating cell debris. "The main problem with cancer is that there are no treatments that stimulate the resolution of inflammatory reactions and reduce cytokine regulation and debris removal," Panegrahi said. Their study suggests that resulfins could be one way to address these problems. However, scientists are still constrained by an exact solution to this problem: how and whether these molecules may help fight cancer. On the other hand, the 2023 Nature study identified how living cancer cells recognize and respond to signals sent by dying cells. The study suggests that blocking dead cell messages could help prevent cancer from reappearing after treatment. More work is needed to figure it out for sure.