In vitro assembly assays also have shown that concentrations of aB crystallin exceeding that of tubulin inhibited microtubule assembly. In separate reports aB crystallin was found to stabilize microtubules by promoting assembly or, in contrast, to prevent disassembly and aggregation. Consistent with the latter studies, aB crystallin expression increased in cells cultured in the presence of microtubule depolymerizing reagents, perhaps to assist with stabilization of the cytoskeleton. While the results of these studies could appear to be in conflict, the hypothesis tested in this report is that the INCB28060 formation of tubulin and aB crystallin quaternary structures can be regulated through common interactive domains that alter the dynamics of their assembly. Furthermore, mammospheres from snail and twist over-expressing cells contained a higher percentage of cells with stem cells markers suggesting that EMT generates cells with stem cells properties. Our findings are consistent with previous studies in which MSC have been shown to interact with breast cancer cells in monolayer cell culture to promote epithelial-mesenchymal transition. Studies on the effect of GAGs on amyloid fibril formation have consisted so far on investigations focusing on a single protein, and on one or a limited number of GAGs. This has allowed the effect of one or more GAGs to be studied only on one particular system and in well defined experimental conditions. Nevertheless, the generic ability of GAGs to influence the process of amyloid fibril formation, independently of the GAG used, protein studied and solution conditions employed, encourages a systematic study using a heterogeneous database reporting different GAGs and protein systems and a variety of solution conditions. In this study we have collected all the experimental data so far published on the effect of GAGs on amyloid fibril formation in vitro. The data include different GAGs, proteins and experimental conditions and have been reported by different investigators. Using a number of single parameter studies, as well as a multivariate analysis, we have studied the database as a whole. We have identified the generic chemical determinants responsible for the GAG-mediated acceleration of amyloid fibril formation, and have used this knowledge to build a predictive equation of the effect of GAGs on protein aggregation. We examined whether exposure to MSC-CM could be enriching for the growth of cells with stem cell properties. However, while primary sphere formation was reproducibly increased in a dose dependent manner in established cell lines, secondary sphere formation was not increased and neither sphere formation nor CD44 + CD242 cells were increased in MDA-IBC-3 tumors cultured with MSC. This suggests that the expansion of mammospheres may represent an amplification of non-selfrenewing progenitors.