|2390 Tumor Stroma Impact on Progression of E-cadherin-deficient, Squamous Cell Carcinoma|
W.E. GOLDMAN1, A. ALT-HOLLAND2, Y. SHAMIS2, T. DESROCHERS2, C. EGLES2, J. MARCHAND2, and J. GARLICK2, 1Tufts University, Quincy, MA, USA, 2Tufts University, Boston, MA, USA|
Specific Aims: It is known that cancer cells are directed by signals from the surrounding tissue microenvironment. We have previously shown that loss of the cell adhesion molecule, E-cadherin, was linked to activation of a highly aggressive phenotype in squamous cell carcinoma (SCC) after in vivo transplantation. However, the mechanism through which loss of E-cadherin leads to a switch to highly aggressive SCC is not clear. We studied if the aggressive behavior manifested by invading tumor cells in vivo, upon loss of cell-cell adhesion is modified by signals from the surrounding stroma.
Methods: To accomplish this, we used engineered human, three-dimensional (3D) tissues that mimic SCC combined with laser capture microdissection (LCM) and microarray analysis to characterize patterns of gene expression in microdissected SCC cells in the presence (3D, in vivo) and absence (3D, in vitro) of tumor stroma. To accomplish this, we compared 3D tissues constructed with E-cadherin-deficient SCC cells grown: (1) in vitro – with only stromal fibroblasts resulting in minimal invasion vs. (2) in vivo – with an in vivo stroma resulting in highly invasive tumor cells upon transplantation of 3D constructs to nude mice. In this way, we tested if molecular pathways in SCC cells were differentially activated in an in vitro vs. in vivo microenvironment.
Results: Epithelial cells were dissected from 3D tissue constructs (Arcturus, Pixcell-II) and RNA was extracted, isolated (PicoPure Kit) and amplified (Target-Amp) for microarray analysis. We successfully isolated RNA from in vitro SCC (305 pg/ul) and in vivo SCC (240 pg/ul – 2150 pg/ul) samples. We are currently performing microarray analysis to determine patterns of gene expression in epithelial cells in the 2 different microenvironments studied.
Conclusions: By comparing patterns of gene expression in SCC cells, we expect to establish the invasion-associated pathways that are specifically activated by cross-talk with the surrounding stroma.
|Seq #240 - Premalignant Oral Lesions and Oral Cancer|
3:30 PM-4:45 PM, Friday, March 23, 2007 Ernest N. Morial Convention Center Exhibit Hall I2-J