QPCR profiling identifies regained and/or lost transcription of EMT and stem cell molecules in MSDACs cultured under alternated growth conditions. (A) Histograms of QPCR profiling analysis showing stem cell-related transcriptional responses regained with the reverted CSC phenotype when MSDACs are reintroduced into SF-SCM. Interestingly, the rescue of stem cell transcriptional responses is relatively heightened when compared with the earlier CSC phenotype stage. (B) Histograms showing the panel of stem cell-related molecules that were significantly lost in the second phase CSC phenotype. Almost all of these molecules showed decreased expression in the non-favorable niche (GM-FBS) and never regained expression when returned to a favorable environment. CSC, cancer stem cell; EMT, epithelial-to-mesenchymal transition; GM-FBS, growth medium with fetal bovine serum; MSDACs, metastatic site-derived aggressive cells; SF-SCM, serum-free stem cell medium.