December 2, 2013 – Toronto is home to one of the world’s leading cancer hospitals called The Princess Margaret and researchers there have disabled the gene that appears to be responsible for the recurrence of the disease after treatment. Called the BMI-1 polycomb ring finger oncogene it is responsible for the regeneration of endogenous stem cells responsible for multiple cancers. So even though a patient’s tumor is initially treated leading to the removal of an existing cancer BMI-1 can trigger the regrowth of cancerous cells.
The research at Princess Margaret has specifically focused on colon cancer and the role BMI-1 plays. What they managed to do is disarm the BMI-1 gene to stop colon cancer stem cells (see image below) from creating a new tumor. They did this by removing colon cancer cells including cancerous stem cells from patients with the disease and exposing the cultures to a new drug BMI-1 gene inhibiting drug that is still being developed and tested. The results – the cancer stem cells were disabled.
Cells from the same cancerous cell culture were also injected into mice specifically bred to tolerate human tissue transplants. The mice grew tumors within a few days. The drug treated cells were then injected into the mice, and then remnants of tumors in these mice were extracted and transplanted into a second group of mice. The results again showed a dramatic drop in cancer stem cells. The results of the study were published on the weekend in Nature Medicine.
For those in the medical field fighting cancer these findings provide a therapy that may permanently end a malignancy eliminating recurrence. The BMI-1 biomarker appears in 65% of patients with colon cancer. By inhibiting self-renewal of cancer cells in patients with the biomarker the recurrence of the disease which happens in about 50% of patients can be eliminated.
It is still too early for clinical trials but BMI-1 cancer treating drugs should be on the market within the next ten years and this research is the first step in getting us there.