Researchers at Princess Margaret Cancer Centre have discovered why multiple myeloma, an incurable cancer of the bone marrow, seems to return even after an initially effective treatment; the answer is Cancer Stem Cells which lie at the heart of tumours and the fact that the chemotherapy drug Velcade doesn't kill them.
Dr. Rodger Tiedemann, a hematologist specializing in multiple myeloma and lymphoma at the Princess Margaret, University Health Network (UHN), Canada (also Assistant Professor in the Faculty of Medicine, University of Toronto) says that the problem lies in the intrinsic resistance found in immature progenitor cells (stem cells) that are the root cause of the disease and its ability to regrow and reform cancer cells. Princess Margaret also has a specialist Multiple Myeloma Unit and two experts there are credited with discovering stem cells in 5 decades ago (1).
Velcade does not kill cancer stem cells
The research demonstrates that the progenitor cells (cancer stem cells) are untouched by mainstay therapy that uses a proteasome inhibitor drug (“Velcade”) to kill the plasma cells that make up most of the tumour. The progenitor cells then proliferate and mature to reboot the disease process, even in patients who appeared to be in complete remission.
“Our findings reveal a way forward toward a cure for multiple myeloma, which involves targeting both the progenitor cells and the plasma cells at the same time,” says Dr. Tiedemann. “Now that we know that progenitor cells persist and lead to relapse after treatment, we can move quickly into clinical trials, measure this residual disease in patients, and attempt to target it with new drugs or with drugs that may already exist.
Dr. Tiedemann says: “If you think of multiple myeloma as a weed, then proteasome inhibitors such as Velcade are like a persnickety goat that eats the mature foliage above ground, producing a remission, but doesn’t eat the roots, so that one day the weed returns.”
Dr. Tiedemann is part of the latest generation of cancer researchers at UHN building on the international legacy of Drs. James Till and the late Ernest McCulloch, who pioneered a new field of science in 1961 with their discovery that some cells (“cancer stem cells”) can self-renew repeatedly.
Current chemo drugs have no effect against cancer stem cells
This is not the first research to show that current cancer drugs have no effect against cancer stem cells. In 2012 Cancer Watch covered three studies on cancer stem cells with researchers concluding that there is no drug currently available that can kill off cancer stem cells. This is why, so often a tumour may be ‘knocked back’ 70 per cent but eventually returns. Cancer Watch also covered NCI research indicating that cancer stem cells could be attacked and destroyed by certain bioactive natural compounds.
Researchers at Princess Margaret have also discovered that 15% of patients have translocation and fare poorly on standard drug treatments. This is presented in a ten year MM overview (2).
Chris Woollams, a founder of CANCERactive and a former Oxford University Biochemist said, "Cancer Stem Cells have been shown to be at the heart of all cancers. And no orthodox drugs attack them, meaning the tumour may decrease by 50,60, or 70% but there is always a chance it will regrow. However there are off-label drugs such as Accutame, Doxycycline and Niclosamide that research suggests can attack these cell. And research on prostate and pancreatic cancers - where there are high levels of cancer stem cells - has shown that natural compounds such as Holy Basil, feverfew, curcumin, lycopene, resveratol, Agaricus mushrooms and Honokiol can play a role in attacking these important cells. Here' are the Top Ten natural compounds to attack cancer stem cells".
Go to: Multiple Myeloma - causes, symptoms and treatment alternatives
*****
References
1. Princess Margaret, Canada, Breakthroughs - https://thepmcf.ca/breakthroughs
2. Overview of MM research - https://ashpublications.org/blood/article/122/21/5315/13040/Outcome-Of-t-4-14-In-Multiple-Myeloma-Princess