Circadian rhythm genes differentially expressed in tumour shown with KEGG PATHWAYS (modified from Kanehisa <i>et al</i>., 2008) (<i>P</i><0.05).

<p>CRY2, PER1, PER3 and NR1D1/Rev-Erb alpha that function as negative regulators of transcription are down-regulated (green) whereas both genes encoding the active transcriptional heterodimeric complex Bmal1(ARNTL):Npas2 (NPAS2) are overexpressed in mesothelioma versus normal parietal pleura. Damaged circadian rhythms may be a key to the continuous replicative force in tumour cells, and thus possible treatment targets.</p

Venn diagram of significantly up- and down-regulated genes (n) in mesothelioma (T) versus normal parietal pleura (pp) and normal visceral pleura (pv) (<i>P</i><0.05).

<p>828 genes are overexpressed (red) and 1004 genes are down-regulated (green) in T versus pp. 341 genes are overexpressed (blue) and 52 genes downregulated (brown) in pv versus pp.</p

Protein expression of selected genes, AGGF1, TYMS and MSLN by immunohistochemistry.

<p>A–C–E: normal parietal pleura. B–D–F: Biphasic mesothelioma with epithelial and sarcomarous components. A–B (x20): AGGF1(VG5Q) mRNA was overexpressed in mesothelioma, and clearly protein was expressed (brown) in both tumour components (arrows). Strong expression in normal mesothelium was seen (arrow) but the majority of endothelial and other pleural cells were negative. C–D (x40): TYMS (Thymidylate synthase) mRNA was overexpressed, also on the protein level (brown), mostly in the epithelial component (arrow) of tumour. Normal pleura was negative. E–F (x20): MSLN (Mesothelin) mRNA was not differentially expressed, that could be explained by the intense protein expression not only in epithelial tumour cells, but also in normal mesothelial and stromal cells.</p

Cell types fraction of nucleated cells in parietal pleura (PP) and tumour (T).

<p>One of the two samples of case no. 10 is removed as non-representative histologically (see text). ND = not done.</p

Differentially overexpressed genes in tumour (red boxes) depicted in the Cell Cycle map from KEGG PATHWAYS (Kanehisa <i>et al</i>., 2008) (<i>P</i><0.05).

<p>21 of 21 cell cycle genes were overexpressed in mesothelioma versus normal parietal pleura tissue. Potential targets for anti-tumour treatment described in the litterature are marked (see text). Abbreviations: CDK7 = cyclin-dependent kinase 7, CHEK1 = checkpoint homolog, E2F2 = E2F transcription factor 2, ORC6L = origin recognition complex, subunit 6 like, MCM2-3-4-6 = minichromosome maintenance complex component 2-3-4-6, PCNA = proliferating cell nuclear antigen, RB1 = retinoblastoma, BUB1 = budding uninhibited by benzimidazoles 1 homolog, BUB1B = BUB1 beta, CDC7 = cell division cycle 7 homolog, APC/C = CDC23, cell division cycle 23 homolog, anaphase-promoting complex subunit 8, CCNB1 = cyclin B1, CCNB2 = cyclin B2, ESPL1 = extra spindle pole bodies homolog 1, CDC2/CDK1 = cell division cycle 2, G1 to S and G2 to M, CDC6 = cell division cycle 6 homolog, CDC20 = cell division cycle 20 homolog, CDC25A = cell division cycle 25 homolog A.</p

A selection of down-regulated gene ontology (GO) entities and genes (Down Genes) in normal parietal pleura versus visceral pleural tissue.

<p>Genes on Chip = the number of genes from each entity represented on the gene chip.</p

RNA isolation and histopathology.

<p>RNA was isolated from parietal pleura (PP) visceral pleura (PV) and mesothelioma (T).</p>*<p>Controls were operated for spontaneous pneumothorax. Histology of the bullae that induced the pneumothorax showed that none had clinical or radiological emphysema.</p

A selection of down-regulated gene ontology (GO) entities and corresponding genes (Genes Down) in mesothelioma versus parietal pleura.

<p>A selection of down-regulated gene ontology (GO) entities and corresponding genes (Genes Down) in mesothelioma versus parietal pleura.</p

Schematic presentation of mesothelioma, the parietal and visceral pleura.

<p>Representative histology showing the most abundant cell types.</p

Schematic presentation of some of the overexpressed genes related to their activity in the various phases of the cell cycle (<i>P</i><0.05).

<p>The M-phase genes are overrepresented.</p