Topoisomerase II inhibition suppresses the proliferation of telomerase-negative cancers.

Telomere maintenance is required for chromosome stability, and telomeres are typically elongated by telomerase following DNA replication. In both tumor and yeast cells that lack telomerase, telomeres are maintained via an alternative recombination mechanism. Previous studies have indicated that yeast Sgs1 and Top3 may work together to remove highly negative supercoils that are generated from recombination.

Brefeldin A reduces anchorage-independent survival, cancer stem cell potential and migration of MDA-MB-231 human breast cancer cells.

Cancer stem cells (CSCs) are a subset of cancer cells in tumors or established cancer cell lines that can initiate and sustain the growth of tumors in vivo. Cancer stem cells can be enriched in serum-free, suspended cultures that allow the formation of tumorspheres over several days to weeks. Brefeldin A (BFA) is a mycotoxin that induces endoplasmic reticulum (ER) stress in eukaryotic cells.

5-azacytidine induces anoikis, inhibits mammosphere formation and reduces metalloproteinase 9 activity in MCF-7 human breast cancer cells.

Cancer stem cells are a subset of cancer cells that initiate the growth of tumors. Low levels of cancer stem cells also exist in established cancer cell lines, and can be enriched in serum-free tumorsphere cultures. Since cancer stem cells have been reported to be resilient to common chemotherapeutic drugs in comparison to regular cancer cells, screening for compounds selectively targeting cancer stem cells may provide an effective therapeutic strategy.