Venn diagram and Volcano plots representing the summary of microarray results. Figure A represents venn diagram, where each circle shows the main effects of Avadis analysis: A16 Vs NA16, A16 Vs Colony and A16 Vs Tumour. Numbers inside each compartment represents the number of transcripts that are significant for that effect. The intersections of the sets represent genes with P < 0.05 and Fold change 2 for each of the effects involved in the intersection. Note the expansion of transcripts that are significant and high from A16 Vs NA16 to A16 Vs Tumour. B, C and D represent Volcano plot comparison of gene expression between A16 Vs NA16, A16 Vs Colony and A16 Vs Tumour. The x axis indicates the differential expression profiles, plotting the fold-induction ratios in a log scale. The y axis indicates the statistical significance of the difference in expression (P value from a t test). Yellow color represents genes with P < 0.05 and Fold change 2. Squares within circles show potentially interesting genes from a biological standpoint. The increase in the fold change was observed from A16 to tumor cells and the genes that were obtained within the significant range were analysed through affymetrix database for different process based on functional annotations as shown in the Additional File 5 Figure S4.