This chapter contains sections titled: Chronic Myeloid Leukemia Chronic Neutrophilic Leukemia Chronic Eosinophilic Leukemia and Hypereosinophilic Syndrome Polycythemia Vera Essential Thrombocythemia Chronic Idiopathic Myelofibrosis Basophil Leukemia and Mast Cell Tumor Mast Cell Tumors
The intraductal papillary-mucinous neoplasms of the pancreas have only recently been recognized as a clinical and pathological entity. They show an adenoma-carcinoma sequence, but have a much more favorable prognosis than ductal adenocarcinoma. Moreover, it has become clear that they constitute a heterogeneous group with at least four histopathological subtypes that have different biological properties with different prognostic implications.
AIMS Induction of apoptosis by the death ligand TRAIL might be a promising therapeutic approach in colorectal cancer therapy. However, some colon cancer cells are resistant to TRAIL because of the expression of anti-apoptotic proteins, such as FLIP. We studied the role of FLIP for apoptosis resistance in colon cancer and developed an approach to overcome the resistance to TRAIL. METHODS The mechanisms of TRAIL-induced cell death in colon cancer cells were studied by Western blot analysis, apoptosis assays, transient and stable transfections, siRNA-mediated knockdown, and FACS analysis. RESULTS The anti-apoptotic protein FLIP is expressed in the majority of colon carcinoma. Stable over-expression of FLIP renders colon carcinoma cells resistant to the death ligand, TRAIL. siRNA-mediated down-regulation of FLIP sensitizes the cells to TRAIL-induced apoptosis. FLIP-expressing colon cancer cells can be sensitized to TRAIL-induced apoptosis by the anti-diabetic drug troglitazone. Troglitazone induces a pronounced reduction in protein expression levels of FLIP. The troglitazone-dependent down-regulation of FLIP occurs on a post-translational level and involves the accelerated FLIP degradation by the proteasome. Moreover, troglitazone suppresses the expression of the anti-apoptotic protein, survivin, and induces the cell surface expression of the TRAIL receptor 2. CONCLUSIONS The anti-apoptotic FLIP protein plays an important role in apoptosis resistance of colon carcinoma cells. Troglitazone down-regulates FLIP and sensitizes the cells to TRAIL-induced apoptosis. A combined treatment with troglitazone and TRAIL might be a promising experimental therapy for some forms of colorectal cancer because troglitazone sensitizes tumor cells to TRAIL-induced apoptosis via various mechanisms, thereby minimizing the risk of acquired tumor cell resistance.
AIM:Overexpression of Aurora-A/STK15 kinase (hereafter AUKRA) is seen in a variety of epithelial cancers, such as gastrointestinal and gynaecological carcinomas. Its role as prognostic and/or predictive marker for adjuvant therapy of patients with advanced ovarian cancer is however still unclear. Therefore, the present study aimed at determining (1) the clinical value of AURKA expression (mRNA and protein) in 115 patients with ovarian carcinomas and (2) the basis of AURKA overexpression at the DNA level.METHODS:Formalin-fixed and Paraffin-embedded tissue samples (ovarian carcinoma: n=115; non-neoplastic ovaries: n=28) were processed for microdissection and quantitative RT-PCR as well as for semi-quantitative immunohistochemistry (IHC) of tissue microarrays according to standardised protocols. Fluorescence in Situ Hybridisation (FISH) was performed in a sub-set of cases (n=37) to analyse AURKA DNA copy numbers.RESULTS:The results demonstrate significantly elevated AURKA expression at the mRNA and protein level in ovarian carcinomas as compared to non-neoplastic ovaries (p < 0.0001). AURKA protein overexpression was observed in 68/107 (63.5%) of cases. For patients with stage III ovarian carcinoma having been optimally debulked and receiving adjuvant Taxane-based chemotherapy, AURKA overexpression was significantly linked to prolonged overall survival (p = 0.02). Finally AURKA overexpression was associated with increased AURKA DNA copy numbers (p = 0.01).CONCLUSION:In summary, AURKA overexpression, which is regulated at the DNA level, is a novel predictive marker for a subgroup of patients with stage III ovarian carcinomas.
Lynch syndrome (formerly called hereditary nonpolyposis colorectal cancer) is a hereditary syndrome resulting in a high risk for colorectal cancer at young age. About 2-3% of all colorectal cancers arise in the setting of Lynch syndrome and the tumors are characterized by microsatellite instabillity (MSI)due to a mutation in one of the mismatch repair genes. Of sporadic colorectal cancer about 15 % have MSI too, but due to hypermethylation of the promotor of the MHL1 gene. Recognizing Lynch syndrome is important, since patients and their families need to undergo a screening program. Based on clinical (colorectal cancer in patients younger than 50 years, or multiple colorectal cancer in one patient) and pathological (mucinous carcinoma, intraepithelial lymphocytes) features pathologists are increasingly able to recognize cases of colorectal cancer that are associated with Lynch syndrome. We propose a cost-effective and ethically correct approach for detecting Lynch syndrome by pathologists.
Testicular germ cell tumors comprise of group of pluripotent tumors including seminomas and nonseminomas, arise from intratubular germ cell neoplasia and originate from the primordial germ cells/ gonocytes. Many well characterized markers of embryonic stem cells including CD9, PODXL and centromere-specific histone-H3-like protein CENPA are consistently expressed in TGCTs. In embryonic stem cells, pluripotency and self renewal capacities are provided by a network of OCT3/4, NANOG and SOX2. In testicular germ cell tumors, pluripotency genes OCT3/4 und NANOG are upregulated both, in seminomas and non-seminomas, while SOX2 is differentially upregulated in embryonal carcinomas only. Similar to embryonic stem cells, most histological elements of type II GCTs are sensitive to chemotherapy and irradiation. Furthermore, all invasive TGCTs show a consistent gain of the short arm of chromosome 12, as found in ES cells upon extensive in vitro culturing. Moreover, the genetic constitution of testicular germ cell tumors can also be linked to characteristics of embryonic stem cells, likely related to their specific inability to repair DNA damage and their high sensitivity to apoptotic cell death. In conclusion, testicular germ cell tumors represent embryonic cancers found in adults. Both the seminomas and nonseminomas have their specific population of stem cells representative of the primordial germ cells/gonocytes and for embryonic stem cells, respectively.
Inbred strains are the raw material for the generation of Genetically Engineered Mice (GEM) that have become indispensable tools for cancer research, and for the identification of genes involved in human diseases. The "German Mouse Clinic" was designed to provide the scientific community with a systematic, standardized and comprehensive phenotyping of mouse models on various genetic backgrounds and generated by different methods (transgenic, knockouts, ENU mutagenesis screen and gene-trap approaches). The pathology screen within the German Mouse-Clinic was conceived to ensure a complete morphologic phenotype of mouse models, to support discovery of genes functions, and to understand how these genes influence the development of human diseases. The goal is to define disease entities that can be recognized by a pathologist and relate them to human disorders when possible. Knowing the inherent morphologic phenotype of the most frequent used mouse strains is of utmost importance for the correct interpretation of mouse models. The main challenges, which pathologist are confronted to validate mouse models for human diseases include (1) knowledge of mouse biology and of histological differences between mouse strains and humans, (2) the terminology that should be used for the classification of neoplastic lesions in GEM's, (3) to asses the usefulness of a particular GEM as model for a human disease.
AIMS:This study addresses the question whether microRNA genes are affected by aberrant hypermethylation and subsequent transcriptional repression in human breast cancer.METHODS:All known human microRNA genes were screened for the association with CpG islands using different algorithms. Methylation status of candidate genes was assessed in a panel of breast cancer cell lines, various normal tissue samples and primary breast cancer specimen using COBRA, bisulfite sequencing and pyrosequencing. Transcriptional silencing was measured by real-time RT-PCR. The effect of demethylation on microRNA gene expression was analysed in breast cancer cell lines after treatment with the DNMT inhibitor 5'-deoxy-2-azacytidine.RESULTS:Aberrant hypermethylation was shown for mir-9-1, mir-124a3, mir-148, mir-152, and mir-663 in 34-86% of cases in a series of 71 primary human breast cancer specimens. miRNA gene hypermethylation correlated strongly with methylation of known tumour suppressor genes (p = 0.003). After treatment of various breast cancer cell lines with the demethylating agent 5-aza-2'deoxycytidine, reduction of mir-9-1 gene methylation and concomitant reactivation of expression could be observed. For the mir-9-1 gene, which is already hypermethylated in preinvasive intraductal lesions, a good correlation between quantitative methylation level and reduction of expression could be demonstrated in a subset of primary human breast cancer specimen (r = 0.8).CONCLUSIONS:In addition to deletion and mutation, microRNA genes are also affected by aberrant hypermethylation in human breast cancer. This epigenetic inactivation is frequent and occurs early during breast cancer progression.
OBJECTIVES:This study analyzes changes in the degree of global methylationlevel in myelodysplastic syndrome during progression of the disease. METHODS:Methylation status was analyzed in 127 patients with histologically confirmed MDS and 26 reactive controls. We employed Pyrosequencing, Luminometric Methylation Assay (LUMA) and a realtime PCR-based quantitative assay. RESULTS:We detected an increase of methylation level of LINE-1 sequences using pyrosequencing and an increase of methylation in the HpaII recognition site employing LUMA during the progression of MDS. Methylation sensitive quantitative PCR showed no statistically significant differences, only a trend. CONCLUSIONS:LINE-1 and methylation sensitive cleavage of DNA can act as a surrogatmarker for global DNA methylation. The genome wide hypermethylation of MDS is a distinct feature of this disease. It discriminates MDS from other neoplasia and may explains the success of hypomethylation inducing reagents like azadeoxycytidine in MDS therapy.
Purpose Although TP53 is one of the most studied genes/proteins in ovarian carcinomas, the predictive value of TP53 alterations is still ambiguous. Experimental design We performed analyses of the TP53 mutational status and its protein expression by immunohistochemistry. Moreover, the single nucleotide polymorphism SNP309 in the P2-promotor of the HDM2 gene was investigated. We correlated the results with the age of onset and the outcome of 107 ovarian carcinoma patients. Results In our study, we identified a large group of patients with TP53 overexpression despite having a wild-type gene (49% of all patients with wild-type TP53). This was associated with a significantly shortened overall survival time (p = 0.019). Patients with TP53 alterations (especially those with overexpression of wild-type TP53) were also more refractory to chemotherapy than patients with normal TP53 (p = 0.027). The Gallele of the SNP309 is associated with an earlier age of onset in estrogen receptor expressing FIGO stage III patients (p = 0.048). In contrast, in FIGO III patients, a weakened TP53 pathway (either G-allele of SNP309 or a TP53 mutation) is correlated with an increased overall survival compared with patients whose tumors are wild-type for TP53 and SNP309 (p = 0.0035). Conclusion Our study provides evidence that both germ line and somatic alterations of the TP53 pathway influence incidence and survival of ovarian carcinoma, and it underscores the importance of assessing the functionality of TP53 in order to predict sensitivity of platin-based chemotherapies and patient outcome.
AIMS:DNA methylation has been shown to play an important role in breast cancer pathogenesis, but up until now it is not clear how the tissue components contribute to the overall methylation of the sample, because microdissection does not provide sufficient material for most standard methylation assays.METHODS:We developed a technology to analyse several methylation markers in a limited number of cells dissected from tissue sections. To evaluate the technology, we analysed, among others, the methylation markers PITX2, RASSF1A and TFF1 in 79 samples of three PITX2 methylation positive invasive ductal carcinomas. The microdissected samples were from the invasive part, the intraductal part, the stroma, tumor infiltrating lymphocytes, chest wall muscle, adipose tissue and healthy ducts.RESULTS:The multiplexed methylation analysis allows for the quantitative analysis of methylation patterns in microdissected samples with as few as 100 genome copies. In all analysed patients PITX2 and RASSF1A were highly methylated in invasive and intraductal carcinoma cells compared to other tissue components. TFF1 behaved inversely. PITX2 showed some methylation in normal adjacent breast tissue. The methylation of the individual markers varied little within one tissue type and between blocks.CONCLUSIONS:This technology is a powerful tool to analyse the methylation of multiple markers in different microdissected tissue components. Methylation patterns may differ significantly between different markers and tissue components. This technology may help to analyse different transitions states of breast and other cancers.
AIMS NF-kappaB has been demonstrated to activate proliferative, inflammatory, and angiogenic processes in ovarian cancer cells in vitro. To add translational information on the situation in vivo, we determined the expression pattern of p65, an important subunit of the classic NF-kappaB pathway, in ovarian carcinoma tissue, and investigated in vivo and in vitro whether this pathway is implicated in the known overexpression of cyclooxygenase-2 (COX-2). METHODS p65 siRNA, chemiluminescent NF-kappaB transcription factor assay, Taqman PCR, as well as immunoblotting were performed with OVCAR-3 ovarian cancer cells. 83 primary ovarian cancinomas as well as 17 cases of benign ovarian tissue were analyzed by p65 and COX-2 immunohistochemistry using a tissue microarray. RESULTS DNA-binding avtivity as well as COX-2 mRNA and protein expression were strongly inducible by IL-1beta treatment in OVCAR-3 cells, while p65 siRNA inhibited IL-1beta-dependent p65 activity (p = 0.037) as well as COX-2 expression on the mRNA (p < 0.03) and on the protein level. In human tumor tissue, p65 protein expression was significantly associated with COX-2 expression (p = 0.002) as well as tumor grading (p = 0.005). Furthermore, p65 expression was a significant prognostic indicator of a reduced patient survival both in univariate (p = 0.038) and in multivariate analysis (p = 0.014). CONCLUSION Our study indicates a deregulation of the classical NF-kappaB pathway in ovarian cancer, which results in the overexpression of the NF-kappaB target gene COX-2. Components of this pathway might constitute novel attractive targets for a specific therapy of advanced ovarian cancer.
UNLABELLED:The conversion of epithelial cells in a mesenchymal cell type is called "epithelial-mesenchymal-transition" (EMT). This process is defined by a loss of epithelial specific characteristics such as cell adhesion, polarity and a reorganization of cytoskeletal proteins. EMT has been shown to be involved in progression of cancer and in obstructive renal fibrosis. In this study we analyzed liver tissues in a bile-duct ligation model of rats and human liver biopsies with cholestatic fibrosis and chronic hepatitis c infection to determine if biliary epithelial cells undergo phenotypical and functional changes during chronic injury.METHODS:Liver tissue of rats and human patients was examined by immunohistochemistry using antibodies against epithelial and mesenchymal specific targets as well as molecules of potentially activated signaling pathways. To study contribution of biliary epithelial cells in extracellular matrix production we performed laser microdissection combined with real-time PCR.RESULTS:Bile duct ligation in rats induced a prominent biliary epithelial proliferation and a pronounced expression of vimentin was observed in biliary epithelial cells, whereas no vimentin expression was detectable in bile duct cells of sham operated rats. In human liver biopsies from patients with cholestatic fibrosis and chronic hepatitis c infection a prominent biliary expression of vimentin could be shown. Despite this, epithelial marker proteins were still detectable. Further, we observed collagen I mRNA expression in laser microdissected bile ducts.CONCLUSION:Biliary epithelial cells show cytoskeletal rearrangements during chronic liver injury towards a mesenchymal phenotype. The detection of collagen I mRNA in bile duct cells suggests that they might participate in extracellular matrix production.
HSP90's are overexpressed in different cancer types and they probably are required to sustain aberrant signalling in malignant cells. Recently, pharmacological inhibition of HSP90 was found to suppress growth of myeloma cell lines and in primary myeloma cells. Therefore, we wanted to investigate the role of HSP90alpha and HSP90beta in the pathogenesis of malignant myeloma (MM) in more detail. Immunohistochemistry was employed to examine the expression of HSP90alpha and HSP90beta in MM. The importance of HSP90 for survival of MM -cells was investigated by SiRNA-mediated knockdown of HSP90 and blockade of the IL-6R/STAT3 and the MAPK signaling pathways in vitro. HSP90alpha and HSP90beta were overexpressed in majority of investigated MM cases, but not in MGUS or in normal plasma cells. SiRNA-mediated knockdown of HSP90 or treatment with the novel HSP90 inhibitor 17-DMAG attenuated the levels of STAT3 and phospho-ERK and decreased the viability of MM cells. The knockdown of HSP90alpha was sufficient to induce apoptosis. This effect was strongly increased when both HSP90s were targeted, indicating a cooperation of both. HSP90 critically contributes to myeloma survival in the context of its microenvironment and therefore strengthen the potential value of HSP90 as a therapeutic target.
GIPC is highly expressed in human pancreatic adenocarcinoma and is a central protein for the stability of IGF-1R in pancreatic adenocarcinoma cell lines (15). The goal of this study was to prove the importance of GIPC in vivo and to evaluate possible therapeutic strategies that target this protein and its PDZ domain. In vivo effects of GIPC knockout were studied after lentiviral transduction of luciferase-expressing MiaPaCa2 pancreatic cancer cells with shRNA against GIPC; growth characteristics were monitored with bioluminiscence. Knockdown of GIPC led to a significant inhibition of pancreatic tumor cell growth in vivo in different mouse models. To test a possible therapeutic approach, the PDZ domain of GIPC was targeted by a short peptide composed of the amino acid sequence PSQSSSEA. This octapeptide was designed based on the C-terminal binding motif of GAIP. Targeting GIPC with this peptide inhibited the association between IGF-1R and GIPC. The subsequent downregulation of IGF-1R decreased proliferation in vitro and in vivo. In conclusion, our findings suggest that targeting GIPC and its PDZ domain-mediated interaction with the tyrosine kinase receptor IGF-1R could be a promising new treatment option for pancreatic cancer.
AIMS:The identification of precursor lesions has a great impact on our understanding of tumorigenesis. In this study we investigated whether preneoplastic lesions can be identified in sporadic gastrinomas and in gastrinomas in multiple endocrine neoplasia type 1 (MEN1) patients. These lesions were tested for loss of heterozygosity (LOH) of the MEN1 gene locus on chromosome 11q13.MATERIAL AND METHODS:Tissue specimens from 25 patients with Zollinger-Ellison syndrome (ZES) were analyzed. The MEN1 status was assessed clinically and by mutational analysis. For simultaneous analysis of hormones and allelic deletions a combined FISH fluorescence in situ hybridization/immunofluorescence protocol was established.RESULTS:Hyperplastic gastrin cell lesions were present in the nontumorous mucosa of all MEN1 patients, but not in 12 patients with sporadic duodenal gastrinomas. The hyperplastic gastrin cells retained both 11q13 alleles. 11q13 LOH was, however, detected in duodenal gastrinomas, some as small as 300 microm in diameter, in 13 patients with MEN1.CONCLUSIONS:MEN1-associated duodenal gastrinomas, but not sporadic gastrinomas, are associated with gastrin cell hyperplasia. It is therefore likely that hyperplastic gastrin cell lesions precede the development of MEN1-associated duodenal gastrinomas. Allelic deletion of the MEN1 gene locus may reflect a decisive initial event in the development of multifocal MEN1-associated gastrinomas from hyperplastic gastrin cell lesions.
The ligand insulin-like growth factor (IGF)-II is highly overexpressed in human hepatocellular carcinoma (HCC) and promotes tumour cell growth. Thus, this signalling axis is a prime target for potential anti-cancer therapies. In this context, gene-specific siRNA against IGF-signalling components as well as IGF1R selective receptor tyrosine kinase (RTK)-inhibitors (tyrphostins) may therefore offer new therapeutic options since both small interfering RNAs (siRNA) and small inhibitory molecules significantly reduce IGFIR signalling in HCC cell lines. However, since highly specific inhibition by siRNA is currently not applicable in the treatment of cancer, selective RTK-inhibitors represent the most promising approach for future therapeutic strategies.
Non-muscle invasive bladder cancer is a heterogenous disease whose management is dependent upon the risk of progression to muscle invasion. Although the recurrence rate is high, the majority of tumors are indolent and can be managed by endoscopic means alone. The prognosis of muscle invasion is poor and radical treatment is required if cure is to be obtained. Progression risk in non-invasive tumors is hard to determine at tumor diagnosis using current clinicopathological means. To improve the accuracy of progression prediction various biomarkers have been evaluated. To discover novel biomarkers several authors have used gene expression microarrays. Various statistical methods have been described to interpret array data, but to date no biomarkers have entered clinical practice. Here, we describe a new method of microarray analysis using neurofuzzy modeling (NFM), a form of artificial intelligence, and integrate it with artificial neural networks (ANN) to investigate non-muscle invasive bladder cancer array data (n=66 tumors). We develop a predictive panel of 11 genes, from 2800 expressed genes, that can significantly identify tumor progression (average Logrank p = 0.0288) in the analyzed cancers. In comparison, this panel appears superior to those genes chosen using traditional analyses (average Logrank p = 0.3455) and tumor grade (Logrank, p = 0.2475) in this non-muscle invasive cohort. We then analyze panel members in a new non-muscle invasive bladder cancer cohort (n=199) using immunohistochemistry with six commercially available antibodies. The combination of 6 genes (LIG3, TNFRSF6, KRT18, ICAM1, DSG2 and BRCA2) significantly stratifies tumor progression (Logrank p = 0.0096) in the new cohort. We discuss the benefits of the transparent NFM approach with respect to other reported methods.
AIMS:Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer related mortality worldwide. The incidence is dramatically increasing and no effective systemic treatments are available accentuating the urgent need for novel treatment approaches. A growing body of evidence suggest that COX-2 signaling is implicated in carcinogenesis and this study was conducted to evaluate the potential of selective COX-2 inhibition for the treatment and prevention of HCCs.METHODS:The significance of COX-2 inhibition in HCCs was investigated in vitro (HCC cell-lines), in vivo (xenotransplanted tumors in nude mice) and ex vivo (precission-cut tissue sclice-cultures). Apoptosis-signaling was analyzed by means of immunohistochemistry, Western Blot analyses, Caspase-assays, FACS analyses after Nicoletti-staining, death receptor FACS-analysis, determination of mitochondrial membrane potential, and siRNA knockdown of Mcl-1.RESULTS:Selective COX-2 inhibition led to a marked tumor-specific growth inhibition of human HCCs in vitro, in vivo and ex vivo based on reduction of proliferation and induction of apoptosis. Both, the death receptor (extrinsic)-, as well as the mitochondrial (intrinsic)-apoptotic pathways were involved. COX-2 inhibition led to an increased surface expression of death receptors and a marked down-regulation of Mcl-1, followed by translocation of Bax to mitochondria and a consecutive release of cytochrome c. Of clinical importance, COX-2 inhibition acted synergistically with chemotherapeutic drugs in the induction of apoptosis whereas primary human-hepatocytes were not sensitized towards apoptosis.CONCLUSION:COX-2 inhibition offers therapeutic and preventive potential in HCC.
