Abstract of the talk: The cancer stem cell (CSC) concept was proposed since decades to explain treatment resistance and tumor recurrences. It is currently admitted the presence of the CSCs in many tumors. CSCs are subpopulation of cells present in the heterogeneous tumor mass in specific tumoral niches. The presence of CSCs explains the clinical observations of tumor recurrences after supposed successful therapies (chemo- and/or radiotherapies). The acknowledge of CSCs properties, including plasticity, quiescence and auto-renewal is in perpetual increase. Despite the techniques evolutions, their identification, isolation and characterization are still very difficult. CSC identification is based on the presence of set of cell-undifferentiated biological markers such as CD133, CD44 and some transcription factors Oct4, Sox2, Nanog... however, these markers are common to the normal stem cells, and are unable to specifically isolate CSCs. Even, using isolation of CSCs based on CD133 positive cells is the most frequently used strategy, using this unique marker is still controversial, and its efficiency is not completely admitted. Since their presence carries the aggressiveness character and properties of many human tumors, their identification and isolation are critical in future therapeutic strategies of tumor eradication.

Presentation given by Dr Sofiane Saada at the workshop on EM field interaction with biological tissues for cancer and regenerative medicine held in Bangor, UK on July 13th 2018. The presentation is entitled "Isolation and characterization of Cancer Stem Cells (CSCs): One question many answers ..."