Profiling of genes regulated by TGF-beta in immortalized skin keratinocyte cells(HaCaT).

TGF-beta is one of the key cytokines implicated in various disease processes including cancer. TGF-beta inhibits growth and promotes apoptosis in normal epithelial cells and in contrast, acts as a pro-tumour cytokine by promoting tumour angiogenesis, immune-escape and metastasis. The effect of TGF-beta on the regulation of gene expression is cell-type specific. In order to identify TGF-beta regulated genes in different cell-types, we followed the expression profiling approach. Keywords: cell type specific response to TGF-beta To identify genes regulated by TGF-beta in different cell-types, we chose HaCaT cells and lung epithelial cells. Cells were plated and propagated in designated media and TGF-beta treatments were carried out in serum free conditions at various time intervals, 1hr, 4hr and 12hr. The RNA was extracted and expression profiling was performed using microarray experiments on 19K cDNA arrays after labeling the cDNAs with Cy3 and Cy5 dyes. The image and data analysis was performed using Quantarray (P.E. Life Sciences, USA) and Avadis (Strand Life Sci. India) softwares. The results are computed as log2 transformed fold changes between treated and untreated cells.