Dr. Weeks’ Comment: Cancer STEM cells, which are resistant to chemotherapy and radiation are the dangerous cancer cell. So when your oncologist recommends these conventional treatments, know that the current science does NOT support the standard of care. Instead chemotherapy and radiation therapy needs to be combined with addressing the lethal cancer STEM cells. “…The combination of radiotherapy with a CSC-targeted therapeutic strategy may prevent tumor recurrence…” Ask your oncologist what cancer STEM cell targeted therapy he or she is offering you!
Long-term recovery of irradiated prostate cancer increases cancer stem cells.
Despite improvements in treatment, prostate cancer (PC) remains the second-leading cause of cancer death in men. Radiotherapy is among the first-line treatments for PC, but a significant number of patients relapse. Recent evidence supports the idea that PC is initiated by a subset of cells, termed cancer stem cells (CSCs). CSCs have also been implicated in radioresistance in various malignancies, but their role in PC has not yet been investigated.
We compared the relative radiosensitivity of isolated CSCs to the total population of their corresponding cell lines, and examined the relative numbers of CSCs in irradiated cell lines following long-term recovery and in recurrent human PC.
Here, we show that while irradiation does not immediately favor increased survival of CSCs, irradiated PC cell lines showed an increase in CSC properties with long-term recovery. These data suggest that, although CSCs are initially damaged by radiation, they possess a greater capacity for recovery and regrowth.
The combination of radiotherapy with a CSC-targeted therapeutic strategy may prevent tumor recurrence.
AND READ THIS…..
“…We conclude that radiation may induce a BCSC phenotype in differentiated breast cancer cells and that this mechanism contributes to increased BCSC numbers seen after classic anticancer treatment…”
Radiation-induced reprogramming of breast cancer cells.
Breast cancers are thought to be organized hierarchically with a small number of breast cancer stem cells (BCSCs) able to regrow a tumor while their progeny lack this ability. Recently, several groups reported enrichment for BCSCs when breast cancers were subjected to classic anticancer treatment. However, the underlying mechanisms leading to this enrichment are incompletely understood. Using non-BCSCs sorted from patient samples, we found that ionizing radiation reprogrammed differentiated breast cancer cells into induced BCSCs (iBCSCs). iBCSCs showed increased mammosphere formation, increased tumorigenicity, and expressed the same stemness-related genes as BCSCs from nonirradiated samples. Reprogramming occurred in a polyploid subpopulation of cells, coincided with re-expression of the transcription factors Oct4, sex determining region Y-box 2, Nanog, and Klf4, and could be partially prevented by Notch inhibition.
We conclude that radiation may induce a BCSC phenotype in differentiated breast cancer cells and that this mechanism contributes to increased BCSC numbers seen after classic anticancer treatment.