Matthias Woenckhaus

WIF1, a component of the Wnt pathway, is down‐regulated in prostate, breast, lung, and bladder cancer

To detect novel Wnt‐pathway genes involved in tumourigenesis, this study analysed the RNA expression levels of 40 genes of the Wnt pathway by chip hybridization of microdissected matched pairs of 54 primary prostate carcinomas. Eleven genes showed greater than two‐fold differential expression in at least 10% of prostate cancers. Three of these genes encode extracellular components of the Wnt pathway (WNT2, WIF1, SFRP4); two are receptors (FZD4, FZD6); two belong to the intracellular signal cascade (DVL1, PPP2CB); one regulates transcription (TCF4); and three represent genes regulated by this pathway (CCND2, CD44, MYC). While SFRP4, FZD4, FZD6, DVL1, TCF4, and MYC are up‐regulated, WIF1, WNT2, PPP2CB, CCND2, and CD44 are down‐regulated in certain prostate cancer patients. Wnt inhibitory factor 1 (WIF1) and secreted frizzled related protein (SFRP4) showed the most significant aberrant expression at the RNA level. WIF1 was down‐regulated in 64% of primary prostate cancers, while SFRP4 was up‐regulated in 81% of the patients. Immunohistochemical analysis using a polyclonal antibody revealed strong cytoplasmic perinuclear WIF1 expression in normal epithelial cells of the prostate, breast, lung, and urinary bladder. Strong reduction of WIF1 protein expression was found in 23% of prostate carcinomas, but also in 60% of breast, 75% of non‐small cell lung (NSCLC), and 26% of bladder cancers analysed. No significant association between WIF1 down‐regulation and tumour stage or grade was observed for prostate, breast or non‐small cell lung carcinomas, indicating that loss of WIF1 expression may be an early event in tumourigenesis in these tissues. However, down‐regulation of WIF1 correlated with higher tumour stage in urinary bladder tumours (pTa versus pT1–pT4; p = 0.038). Copyright

Smoking and cancer-related gene expression in bronchial epithelium and non-small-cell lung cancers.

Tobacco smoking is the leading cause of lung cancer worldwide. Gene expression in surgically resected and microdissected samples of non‐small‐cell lung cancers (18 squamous cell carcinomas and nine adenocarcinomas), matched normal bronchial epithelium, and peripheral lung tissue from both smokers (n = 22) and non‐smokers (n = 5) was studied using the Affymetrix U133A array. A subset of 15 differentially regulated genes was validated by real‐time PCR or immunohistochemistry. Hierarchical cluster analysis clearly distinguished between benign and malignant tissue and between squamous cell carcinomas and adenocarcinomas. The bronchial epithelium and adenocarcinomas could be divided into the two subgroups of smokers and non‐smokers. By comparison of the gene expression profiles in the bronchial epithelium of non‐smokers, smokers, and matched cancer tissues, it was possible to identify a signature of 23 differentially expressed genes, which might reflect early cigarette smoke‐induced and cancer‐relevant molecular lesions in the central bronchial epithelium of smokers. Ten of these genes are involved in xenobiotic metabolism and redox stress (eg AKR1B10, AKR1C1, and MT1K). One gene is a tumour suppressor gene (HLF); two genes act as oncogenes (FGFR3 and LMO3); two genes are involved in matrix degradation (MMP12 and PTHLH); three genes are related to cell differentiation (SPRR1B, RTN1, and MUC7); and five genes have not been well characterized to date. By comparison of the tobacco‐exposed peripheral alveolar lung tissue of smokers with non‐smokers and with adenocarcinomas from smokers, it was possible to identify a signature of 27 other differentially expressed genes. These genes are involved in the metabolism of xenobiotics (eg GPX2 and FMO3) and may represent cigarette smoke‐induced, cancer‐related molecular targets that may be utilized to identify smokers with increased risk for lung cancer. Copyright

Elevated nuclear maspin expression is associated with microsatellite instability and high tumour grade in colorectal cancer.

Maspin, a member of the serpin family, has been reported to suppress metastasis and angiogenesis in breast and prostate cancers. Overexpression of maspin was associated with adverse prognostic features in several other tumours. In this study, expression of maspin was analysed in 41 colorectal carcinomas with high‐frequency microsatellite instability (MSI‐H) and 159 microsatellite stable colorectal cancers (MSS/MSI‐L) by immunohistochemistry (IHC) and partly by relative quantitative real‐time RT‐PCR and western blot analyses. Significant upregulation of maspin expression was found in MSI‐H tumours compared to both MSS/MSI‐L tumours and matched benign colonic mucosa. Increased maspin expression was also found in three MSI‐H colon cancer cell lines, but not in three MSS colon cancer cell lines by RT‐PCR and western blot analyses. Regulation of maspin expression depended on promoter methylation as tissue specimens and cell lines expressing maspin showed unmethylated maspin promoters, whereas promoter hypermethylation was found in specimens with loss of maspin expression. Intense nuclear maspin immunostaining was seen specifically in MSI‐H tumours (p = 0.013), de‐differentiated tumours (p = 0.006), and at the invasion front. These findings provide new insights into the role of maspin in colorectal cancer progression and may be useful for diagnosis and treatment strategies. Copyright

Induction of apoptosis before shedding of human intestinal epithelial cells

OBJECTIVES:Human intestinal epithelial cells (IECs) derive from stem cells at the crypt base and migrate along the so-called crypt-villus axis toward the intestinal lumen. As they reach the luminal surface in the colon or the villus tip in the small intestine, IECs are shed and their life cycle is terminated. The role of apoptosis during IEC migration along the crypt-villus axis has been subject to studies with conflicting results. In this study we use a novel approach to identify the initiation of apoptosis within normal human IECs.METHODS:Normal mucosa from the large and small human intestine was analyzed employing a novel antibody directed against activated caspase-3—an early marker of apoptosis.RESULTS:IECs initiate the apoptotic cascade as they approach the area of shedding before displaying evident morphological features of apoptosis. IECs of the small bowel also show caspase-3 activation in the small intestinal crypt base, whereas IECs of the colononic crypt base rarely show evidence of ongoing apoptosis.CONCLUSIONS:These findings indicate that apoptosis is initiated in human IECs as they reach the luminal surface/villus tip and before shedding. Furthermore, they show that different sections of the intestinal tract vary significantly in the rate of IEC apoptosis, possibly reflecting their difference in susceptibility to epithelial cell neoplasia.

Nuclear Maspin expression is associated with response to adjuvant 5-fluorouracil based chemotherapy in patients with stage III colon cancer.

Maspin, a member of the Serpin protease inhibitor family, is overexpressed in poorly differentiated colorectal tumors and more frequently found in tumors with microsatellite instability. Immunohistochemical nuclear Maspin staining is predominantly seen in tumor cells at the invasion front of such cancers, suggesting that this molecule is associated with local tumor cell infiltration and aggressiveness. In a retrospective study, we studied nuclear Maspin expression as a potential prognostic tool in a total of 172 primary stage III colon cancers by immunohistochemistry. Of those 172 patients, 76 were treated by surgery only, and 96 patients received additional adjuvant 5‐fluorouracil (5‐FU) based chemotherapy. Nuclear Maspin expression was an independent adverse prognostic factor for overall survival in our patient cohort (hazard ratio 2.08; 95% CI, 1.13–3.81; p = 0.018). However, patients with primary tumors expressing Maspin in the nucleus showed a significant treatment benefit from 5‐FU chemotherapy (hazard ratio 0.384; 95% CI, 0.188–0.784; p = 0.009) compared to adjuvantly treated patients whose tumors did not express this molecule. Nuclear Maspin expression is highly predictive of 5‐FU chemotherapy response in patients with advanced stage colon cancer. Patients with negative immunhistochemical Maspin expression do not benefit from 5‐FU treatment and may be candidates for an alternative (non‐5‐FU based) adjuvant therapy regime.

Expression of the MAP kinase phosphatase DUSP4 is associated with microsatellite instability in colorectal cancer (CRC) and causes increased cell proliferation

DUSP4 (MKP‐2), a member of the mitogen‐activated protein kinase phosphatase (MKP) family and potential tumor suppressor, negatively regulates the MAPKs (mitogen‐activated protein kinases) ERK, p38 and JNK. MAPKs play a crucial role in cancer development and progression. Previously, using microarray analyses we found a conspicuously frequent overexpression of DUSP4 in colorectal cancer (CRC) with high frequent microsatellite instability (MSI‐H) compared to microsatellite stable (MSS) CRC. Here we studied DUSP4 expression on mRNA level in 38 CRC (19 MSI‐H and 19 MSS) compared to matched normal tissue as well as in CRC cell lines by RT‐qPCR. DUSP4 was overexpressed in all 19 MSI‐H tumors and in 14 MSS tumors. Median expression levels in MSI‐H tumors were significantly higher than in MSS‐tumors (p < 0.001). Consistently, MSI‐H CRC cell lines showed 6.8‐fold higher DUSP4 mRNA levels than MSS cell lines. DUSP4 expression was not regulated by promoter methylation since no methylation was found by quantitative methylation analysis of DUSP4 promoter in CRC cell lines neither in tumor samples. Furthermore, no DUSP4 mutation was found on genomic DNA level in four CRC cell lines. DUSP4 overexpression in CRC cell lines through DUSP4 transfection caused upregulated expression of MAPK targets CDC25A, CCND1, EGR1, FOS, MYC and CDKN1A in HCT116 as well as downregulation of mismatch repair gene MSH2 in SW480. Furthermore, DUSP4 overexpression led to increased proliferation in CRC cell lines. Our findings suggest that DUSP4 acts as an important regulator of cell growth within the MAPK pathway and causes enhanced cell growth in MSI‐H CRC.

Association of Crohn’s disease and latent celiac disease: a case report and review of the literature

BackgroundCrohn’s disease is a chronic inflammatory disease of the intestine potentially affecting all parts of the intestine with predilection sites in the terminal ileum and proximal colon. Its prevalence in Western Europe is 20–40/100,000 with equal affection of both sexes and familiar accumulation. Histopathologically, it is characterized by a discontinuous, segmental manifestation and implication of all intestinal layers. Celiac disease, on the other hand, is defined by histologically proven villous atrophy associated with hyperplasia of crypts, lymphocytic infiltration and clinical improvement after a gluten-free diet.Case reportWe report the case of a 52-year-old man presenting with long-term diarrhea and loss of weight associated with Crohn’s disease. After interventional therapy for an unstable coronary artery syndrome and medical therapy for hyperthyroidism, the diarrhea stopped only after maintaining a gluten-free diet. A latent form of celiac disease (clinical symptoms, improvement after gluten-free diet, detection of anti-gliadin IgA antibodies, negative histology) was diagnosed.ConclusionTo our knowledge, this is the first report on the association of Crohn’s disease and the latent form of celiac disease in the same patient. Whereas in most cases, Crohn’s disease develops secondary to a pre-existing celiac disease, in our patient, latent celiac disease was diagnosed years after the onset of and therapy for Crohn’s disease.

Nuclear and cytoplasmic Maspin expression in primary non-small cell lung cancer

Aim: To investigate whether nuclear and cytoplasmic Maspin expression is associated with distinct clinicopathological parameters and TP53 expression in a representative series of primary non-small cell lung cancer (NSCLC). Methods: Tissue microarrays (n = 487) were used to immunohistochemically analyse expression of Maspin and TP53. Cytoplasmic and nuclear expression of Maspin was scored on the basis of the percentage of positive tumour cells. Univariate analysis of clinicopathological variables potentially affecting tumour-specific survival was performed. Results: Immunohistochemical Maspin expression (nuclear and cytoplasmic) was informative in 72.3% (352/487) of cases. Cytoplasmic and nuclear Maspin immunoreactivity in ⩾10% of tumour cells was detected in 37.8% (133/352) and 65.3% (230/352) of informative cases, respectively. Nuclear and cytoplasmic Maspin staining was observed more frequently in primary squamous cell carcinomas than in other lung cancer types. Only nuclear Maspin immunoreactivity was significantly associated with positive TP53 staining. Cytoplasmic or nuclear Maspin expression was not associated with tumour-specific survival. Conclusion: Maspin expression was found both in the nucleus and the cytoplasm of NSCLC, more frequently in squamous cell carcinomas. However, no association with tumour-specific survival could be demonstrated.

Multitarget FISH and LOH Analyses at Chromosome 3p in Non–Small Cell Lung Cancer and Adjacent Bronchial Epithelium

Multitarget fluorescence in situ hybridization (FISH; LAVysion, Vysis, Downers Grove, IL) targeting chromosomes 6p11-q11, 7p12, 8q24, and 5p15.2 was compared with results of microsatellite studies at chromosome 3p to identify molecular changes associated with tobacco use and tumor development in non-small cell lung cancer (NSCLC). Analyses were performed on 26 NSCLCs and matched benign bronchial epithelium; samples from 10 patients without NSCLC served as control samples. Significant molecular differences between tumor tissue and corresponding benign bronchi were found using FISH (P = .001) and loss of heterozygosity (LOH) analysis (P = .031). Bronchial epithelium from patients with NSCLC was genetically different from epithelium from patients without NSCLC in FISH analysis (P = .025). Receiver operating characteristic curve analysis revealed an optimal cutoff value of 5% atypical cells for bronchial epithelium. There was no statistical correlation with the patients smoking history, and LOH analysis of bronchi did not differentiate between patients with and without NSCLC. Multicolor FISH analysis is able to detect a tumor-associated molecular field effect in bronchi adjacent to NSCLC.

Microsatellite analysis of pleural supernatants could increase sensitivity of pleural fluid cytology

Pleural effusions may result from various inflammatory, hemodynamic, or neoplastic conditions. A common diagnostic problem lies in distinguishing malignant from benign pleural effusions using routine cytological evaluation. We studied pleural fluid samples obtained from 14 patients with histologically confirmed malignancy and from 6 patients with benign pleural effusions using 12 microsatellite markers from 8 different chromosomal regions. Supernatants and cellular sediments of all 20 pleural fluid samples were analyzed. Routine cytological examination was 100% specific for malignancy but was only 57% sensitive. Microsatellite analyses of pleural fluid supernatants showed genetic alterations in tumor patients only. However, 50% of pleural effusions that were considered negative for malignancy by routine cytological analysis showed either loss of heterozygosity or microsatellite instability. The sensitivity of pleural fluid examination rose to 79% when routine cytological assessment was supplemented by molecular studies. Our data suggest that microsatellite analysis increases the sensitivity of cytological pleural fluid examination in assessing potential malignancy and that combining cytological and molecular methods may improve yield and certainty in diagnostically challenging cases.