Scientists at The University of Toledo investigating improvements to a commonly used chemotherapy drug have discovered an entirely new class of cancer-killing agents that show promise in eradicating cancer stem cells.
Their findings could prove to be a breakthrough in not only treating tumors, but ensuring cancer doesn't return years later -- giving peace of mind to patients that their illness is truly gone. Everyone is trying to figure out how to kill them, and this may be one way to do it.
Killing cancer cells with super glue
Taylor and Dr. Viranga Tillekeratne, a professor in the Department of Medicinal and Biological Chemistry in the UToledo College of Pharmacy and Pharmaceutical Sciences, reported their findings in a paper recently published in the journal Scientific Reports. Cancer stem cells are an intriguing target for researchers because of their potential to re-seed tumors.
When doctors remove a tumor surgically or target it with chemotherapy drugs or radiation therapy, the cancer may appear to be gone. Engineered by US cancer expert Professor Yuman Fong, the treatment is being developed by Australia biotech company Imugene, which has licensed the innovation.
Professor Fong is in Australia this week to meet Imugene representatives and plan the clinical trials. Researchers believe this will show where the treatment is most effective faster than just testing in one cancer.
Just because the treatment works in mice does not mean it will be successful in humans and early phase human trials are known as the valley of death for many medical breakthroughs. However, Professor Fong is hopeful because a series of other more specific cancer killing viruses are already proving effective in fighting cancer in humans. US scientists have turned the virus that causes the common cold into a treatment to kill brain cancer — in some patients the cancer disappeared for years before returning, in others it shrank the tumours considerably.
A modified form of the herpes or cold sore virus called Imlygic or T-Vec is being used to treat melanoma. Australian Researcher Associate professor Tom John from the Olivia Newton John Cancer Research Institute recently tested another virus treatment in combination with immunotherapy Keytruda on 11 lung cancer patients and 3 patients saw their tumours shrink. A new type of virus has been created that can kill every type of cancer in a petrie dish. Doctors failing to diagnose cancer. Previous research using viruses to kill cancers failed because the viruses used were too toxic, other treatments are only able to deal with cancers in specific cells like skin or liver tissue.
The breakthrough treatment will see cancer patients have the engineered virus injected directly into their tumours where it is expected to infect the cancer cells and explode them. The virus is then expected to alert the immune system that there are cancer cells in the body and prompt it to seek out and kill other diseased cells.
The idea that a separate type of tumor cell lies at the root of cancer completely reworks existing dogma about how cancers form, gain structure, and spread. The notion of a separate subset of cells within tumors, says Gil G. Mor, M. We were taught that tumors are a mass of identical cells. These are seeding cells—cancer cells that are different from other cancer cells. Thomas J.
Lynch Jr. There is no doubt we have to target them to halt the process. While oncologists almost universally acknowledge that only genetically aberrant hematopoietic stem cells can generate blood cancers, including most leukemias, there is no definitive way to distinguish cancer stem cells in solid-tumor cancers. But Santin and Mor say that they have characterized traits of these cells, including unique surface proteins, in certain cancers that distinguish them from other cells within solid tumors.
Uncloaking sarcoma to the immune system
That characterization may provide targets for the development of new anticancer agents. Several efforts are now under way at Yale and elsewhere to find therapies that attack those so-called stem cells. If the researchers succeed, a revolution in the way oncologists view—and more importantly—treat cancer may be in the offing.
But despite huge investments in treatment that have drawn on those insights, including the introduction more than 30 years ago of commonly used platinum-based chemotherapeutic agents, the odds and length of survival for most patients newly diagnosed with advanced solid-tumor cancers have barely increased. Eventually, in most cases of ovarian cancer—as well as lung, colorectal, breast, pancreatic, brain, and other solid organ-tissue cancers—the malignancy recurs after treatment, and that very often presages death.
Mainstream cancer biology points to tumor cells that escape even the most powerful targeted treatments as the culprits in cancer recurrence.
But the cancer stem cell theory puts treatment resistance and cancer recurrence in a very different light. That opinion contrasts with traditional models of cancer biology. According to the most widely held view, malignant cells have mutations that make them genetically unstable. They accumulate further mutations and evolve into tumors that grow rapidly, encourage blood vessel formation, discourage immune responses, metastasize, and resist treatment. Furthermore, within the tumor there is a hierarchy. That only happens with the cancer stem cells.
Lin agrees. But the most basic questions about the biology of cancer stem cells await answers because the existence of uniquely potent tumor-initiating cells with stem cell-like characteristics remains unproven. The cancer stem cell theory arose out of a paradox observed in certain cancers in laboratory studies.
Mechanism Encourages the Self-killing of Cancer Cells | Technology Networks
Tumor cells—even large numbers of them—may fail to generate new tumors when transplanted into immunodeficient laboratory mice. At the same time, other tumor cells—sometimes just single cells—can generate new tumors physiologically identical to the parent cancer, and also spontaneously generate metastases.
In cancer biologists at the University of Toronto found that very specific human acute myeloid leukemia AML cells were needed to transmit the disease into immunocompromised mice. Only leukemia stem cells can. Nine years after the Toronto discovery, however, the research focus began to shift from cancers of the blood to solid-tumor cancers.
In , University of Michigan researchers separated populations of what they said were rare stem cell-like cells from other cancer cells within specimens from human breast cancer tumors. Since then scientists say they have characterized populations of cells resembling stem cells in many types of solid tumors through elevated levels of proteins typically found only on the surface of stem cell membranes.