Cancer stem cells – the current status of an old concept: literature review and clinical approaches

Abstract

As regards their morphology and biology, tumours consist of heterogeneous cell populations. The cancer stem cell (CSC) hypothesis assumes that a tumour is hierarchically organized and not all of the cells are equally capable of generating descendants, similarly to normal tissue. The only cells being able to self-renew and produce a heterogeneous tumour cell population are cancer stem cells. CSCs probably derive from normal stem cells, although progenitor cells may be taken into consideration as the source of cancer stem cells. CSCs reside in the niche defined as the microenvironment formed by stromal cells, vasculature and extracellular matrix. The CSC assays include FACS sorting, xenotransplantation to immunodeficient mice (SCID), incubation with Hoechst 33342 dye, cell culture in non-adherent conditions, cell culture with bromodeoxyuridine. CSCs have certain properties that make them resistant to anticancer therapy, which suggests they may be the target for potential therapeutic strategies.

Translational potential of cancer stem cells: A review of the detection of cancer stem cells and their roles in cancer recurrence and cancer treatment

“…In addition, techniques such as immunocytochemistry, immunofluorescence and immunohistochemistry are used to identify cancer stem cells based on the level and site of expression of protein markers [21]. The gold standard functional assay for detection and isolation of CSCs is xenotransplantation into immune-deficient animals [32]. As these methods have advantages and disadvantages based on their experimental setup, a combination of these methods would be more reliable to detect and isolate of CSCs.…”

Stem Cells and Cancer

“…reversal of differentiation. In the mid-20 th century, when stem cells were gaining more attention, the concept binding together tumors and stem cells became attractive again [12].…”

Cancer Stem Cells: Understanding their Dynamics

“…These cells get influenced by microenvironmental influences exhibited by stromal cells and extracellular matrix. Cancer stem cells distinctly possess a feature of xenobiotic efflux due to an increased expression of membrane-bound proteins belonging to the ABC transporter family [2]. The cancer stem cell hypothesis assumes an hierarchial structure of cancer stem cells which is capable of self-renewal and heterogenous cell population production [2].…”