Optimized release matrices for use in a BioMEMS device to study metastasis

Multiple changes within the tumor microenvironment have been correlated with an increase in metastasis, yet the mechanisms are not fully understood. Tumor cells can be stimulated by the release of chemoattractant factors such as epidermal growth factor (EGF) from nearby stromal cells, resulting in increased intravasation and metastasis. Additionally, altered extracellular matrix density can result in changes in gene expression patterns governing increased cellular proliferation and motility. The Nano Intravital Device (NANIVID) has been used to produce gradients of select soluble factors in the tumor microenvironment and to study the role of these changes on cell migration. In previous studies, the NANIVID utilized a synthetic hydrogel to produce an EGF gradient to attract metastatic breast cancer cells. In this work, a matrigel insert will be introduced into the outlet to provide a substrate for cells to migrate on when entering the device. The concentration of the chemoattractant and matrigel comprising the insert will be optimized to produce a suitable gradient for inducing chemotaxis in metastatic breast cancer cells in vitro. Additionally, silk and alginate matrices will be explored as improved soluble factor release mediums. Delivery of larger molecules such as collagen cross-linkers requires an alternative hydrogel material. Future NANIVID experiments will utilize these materials to gauge the cellular motility response when a stiffer matrix is encountered.