Transcription profiling of human MIAPaCa2 cells re-expressing the alpha2 integrin or truncation mutations of alpha2 integrin

ABSTRACT: Previous reports demonstrate that the α2-integrin (α2) mediates pancreatic ductal adenocarcinoma (PDAC) cell interaction with collagens. We found that untransformed pancreatic ductal epithelial cells and well-differentiated PDAC cells use α2 exclusively to adhere and migrate on collagenI. In contrast, poorly-differentiated PT45P1 and MIAPaCa2 cells demonstrate reduced reliance on, or complete loss of α2, respectively. Further, well-differentiated PDAC lines exhibit reduced in vitro invasion compared to poorly-differentiated lines, and α2-blockade suppressed invasion of well-differentiated lines exclusively. Based on these data and the demonstrated role of α2 in maintaining tissue architecture in other organs, we hypothesized that α2 may actually suppress the malignant phenotype in PDAC. Accordingly, stable ectopic expression of α2 in MIAPaCa2 cells (MP2-α2) retarded in vitro invasion. MP2-α2 cells maintained on collagenI were more invasion-retarded than MP2-α2 cells maintained in standard tissue culture, and demonstrated higher α2β1 expression that was reflected in faster and more complete adhesion/migration on collagenI. Affymetrix gene expression profiling of α2-expressing and mock-transfected cells revealed that kallikrein-related peptidases (KLK)-5, 6 and 7 were specifically upregulated by α2. Accordingly, well-differentiated PDAC lines express KLK-5, 6 and 7 and KLK blockade increased invasion as well as collagenI-migration in KLK-positive lines. Importantly, an α2 cytoplasmic deletion mutant promoted KLK expression and retarded invasion, while an α9α2 chimera retarded invasion less efficiently, and did not impact KLK expression. These data demonstrate for the first time that the α2-ectodomain and KLKâ??s coordinately regulate a less invasive phenotype in PDAC cells. Experiment Overall Design: Affymetrix global gene arrays were used to analyse differences in gene expression patterns in MIAPaCa2 cells stably reexpressing the alpha2 integrin, a cytoplasmic deletion of the alpha2 integrin (dCYTO) or an alpha9 ectodomain and transmembrane domain/alpha2 cytoplasmic domain chimera, versus vector-only mock controls. RNA was harvested from cells passaged identically and maitained under standard tissue culture conditions or on collagenI- or tenascin FNIII-coated plates.. Experiment Overall Design: Genetic manipulation (stable transgene expression)

ORGANISM(S): Homo sapiens

SUBMITTER: Jian-Liang Li 

PROVIDER: E-GEOD-18277 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress