CAS (cellular apoptosis susceptibility) gene expression in ovarian carcinoma: Correlation with 20q13.2 copy number and cyclin D1, p53, and Rb protein expression

The Intricate Interplay between the ZNF217 Oncogene and Epigenetic Processes Shapes Tumor Progression

The oncogenic transcription factor ZNF217 orchestrates several molecular signaling networks to reprogram integrated circuits governing hallmark capabilities within cancer cells. High levels of ZNF217 expression provide advantages to a specific subset of cancer cells to reprogram tumor progression, drug resistance and cancer cell plasticity. ZNF217 expression level, thus, provides a powerful biomarker of poor prognosis and a predictive biomarker for anticancer therapies. Cancer epigenetic mechanisms are well known to support the acquisition of hallmark characteristics during oncogenesis. However, the complex interactions between ZNF217 and epigenetic processes have been poorly appreciated. Deregulated DNA methylation status at ZNF217 locus or an intricate cross-talk between ZNF217 and noncoding RNA networks could explain aberrant ZNF217 expression levels in a cancer cell context. On the other hand, the ZNF217 protein controls gene expression signatures and molecular signaling for tumor progression by tuning DNA methylation status at key promoters by interfering with noncoding RNAs or by refining the epitranscriptome. Altogether, this review focuses on the recent advances in the understanding of ZNF217 collaboration with epigenetics processes to orchestrate oncogenesis. We also discuss the exciting burgeoning translational medicine and candidate therapeutic strategies emerging from those recent findings connecting ZNF217 to epigenetic deregulation in cancer.

Identification and validation of a novel signature as a diagnostic and prognostic biomarker in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignant neoplasms worldwide. Although marker genes associated with CRC have been identified previously, only a few have fulfilled the therapeutic demand. Therefore, based on differentially expressed genes (DEGs), this study aimed to establish a promising and valuable signature model to diagnose CRC and predict patient's prognosis.

METHODS

The key genes were screened from DEGs to establish a multiscale embedded gene co-expression network, protein-protein interaction network, and survival analysis. A support vector machine (SVM) diagnostic model was constructed by a supervised classification algorithm. Univariate Cox analysis was performed to construct two prognostic signatures for overall survival and disease-free survival by Kaplan-Meier analysis, respectively. Independent clinical prognostic indicators were identified, followed by univariable and multivariable Cox analysis. GSEA was used to evaluate the gene enrichment analysis and CIBERSORT was used to estimate the immune cell infiltration. Finally, key genes were validated by qPCR and IHC.

RESULTS

In this study, four key genes (DKC1, FLNA, CSE1L and NSUN5) were screened. The SVM diagnostic model, consisting of 4-gene signature, showed a good performance for the diagnostic (AUC = 0.9956). Meanwhile, the four-gene signature was also used to construct a risk score prognostic model for disease-free survival (DFS) and overall survival (OS), and the results indicated that the prognostic model performed best in predicting the DFS and OS of CRC patients. The risk score was validated as an independent prognostic factor to exhibit the accurate survival prediction for OS according to the independent prognostic value. Furthermore, immune cell infiltration analysis demonstrated that the high-risk group had a higher proportion of macrophages M0, and T cells CD4 memory resting was significantly higher in the low-risk group than in the high-risk group. In addition, functional analysis indicated that WNT and other four cancer-related signaling pathways were the most significantly enriched pathways in the high-risk group. Finally, qRT-PCR and IHC results demonstrated that the high expression of DKC1, CSE1L and NSUN5, and the low expression of FLNA were risk factors of CRC patients with a poor prognosis.

CONCLUSION

In this study, diagnosis and prognosis models were constructed based on the screened genes of DKC1, FLNA, CSE1L and NSUN5. The four-gene signature exhibited an excellent ability in CRC diagnosis and prognostic prediction. Our study supported and highlighted that the four-gene signature is conducive to better prognostic risk stratification and potential therapeutic targets for CRC patients.

Cellular apoptosis susceptibility (CAS) is linked to integrin β1 and required for tumor cell migration and invasion in hepatocellular carcinoma (HCC)

Importins and exportins represent an integral part of the nucleocytoplasmic transport machinery with fundamental importance for eukaryotic cell function. A variety of malignancies including hepatocellular carcinoma (HCC) show de-regulation of nuclear transport factors such as overexpression of the exportin Cellular Apoptosis Susceptibility (CAS). The functional implications of CAS in hepatocarcinogenesis remain, however, poorly understood. Here we integrated proteomics, transcriptomics and functional assays with patient data to further characterize the role of CAS in HCC. By analyzing ∼ 1700 proteins using quantitative mass spectrometry in HCC cells we found that CAS depletion by RNAi leads to de-regulation of integrins, particularly down-regulation of integrin β1. Consistent with this finding, CAS knockdown resulted in substantially reduced migration and invasion of HCC cell lines as analyzed by 2D ‘scratch’ and invasion chamber assays, respectively. Supporting the potential in vivo relevance, high expression levels of CAS in HCC tissue samples were associated with macroangioinvasion and poorer patient outcome. Our data suggest a previously unanticipated link between CAS and integrin signaling which correlates with an aggressive HCC phenotype.

Zinc finger gene 217 (ZNF217) Promoted Ovarian Hyperstimulation Syndrome (OHSS) through Regulating E2 Synthesis and Inhibiting Thrombospondin-1 (TSP-1)

Zinc finger gene 217 (ZNF217) is a candidate gene of polycystic ovary syndrome (PCOS) which is vulnerable to ovarian hyperstimulation syndrome (OHSS). However, the relationship between ZNF217 and OHSS is largely unknown. Our study demonstrated that ZNF217 was mainly distributed in the granulosa cells of rat ovary. Significantly higher expression of ovarian ZNF217 was detected in OHSS rats, being consistent with serum 17β-estradiol concentration and ovarian aromatase. Moreover, OHSS rats also showed decreased ovarian TSP-1 mRNA, an acknowledged VEGF signaling suppressor. The same changes were detected in human granulosa cells and follicular fluid. Thus, the increased ZNF217 and decreased TSP-1 may participate in OHSS onset. In vitro experiment revealed that ZNF217 positively regulated E₂ synthesis through promoting cAMP response element binding protein (CREB) and thereby CYP19A1 in KGN cells. Furthermore, ZNF217 negatively regulated TSP-1 in KGN cells while TSP-1 promoted claudin1 and inhibited nitric oxide (NO) in HUVECs and HAECs. Both of claudin1 and NO are responsible for the regulation of vascular permeability (VP). Therefore, we demonstrated that ZNF217 contributed to OHSS onset through promoting E₂ synthesis and the increase of VP. Moreover, the increased ZNF217 and decreased TSP-1 provided new targets for the prevention or treatment of OHSS in the future.

The dark side of ZNF217, a key regulator of tumorigenesis with powerful biomarker value

The recently described oncogene ZNF217 belongs to a chromosomal region that is frequently amplified in human cancers. Recent findings have revealed that alternative mechanisms such as epigenetic regulation also govern the expression of the encoded ZNF217 protein. Newly discovered molecular functions of ZNF217 indicate that it orchestrates complex intracellular circuits as a new key regulator of tumorigenesis. In this review, we focus on recent research on ZNF217-driven molecular functions in human cancers, revisiting major hallmarks of cancer and highlighting the downstream molecular targets and signaling pathways of ZNF217. We also discuss the exciting translational medicine investigating ZNF217 expression levels as a new powerful biomarker, and ZNF217 as a candidate target for future anti-cancer therapies.

CAS (CSE1L) signaling pathway in tumor progression and its potential as a biomarker and target for targeted therapy

CSE1L (chromosome segregation 1-like protein), also named as CAS (cellular apoptosis susceptibility protein), is highly expressed in most cancer types. CSE1L/CAS is a multiple functional protein that plays roles in apoptosis, cell survival, chromosome assembly, nucleocytoplasmic transport, microvesicle formation, and cancer metastasis; some of the functions are explicitly correlated. CSE1L is also a cancer serum biomarker. The phosphorylation of CAS is regulated by the extracellular signal-regulated kinase (ERK). The RAS/RAF/MAPK/ERK signaling pathways are the essential targets of most targeted cancer drugs, thus serum phosphorylated CSE1L may be a potential biomarker for monitoring drug resistance in targeted therapy. CSE1L can regulate Ras-induced ERK phosphorylation. CSE1L also regulates the expression and phosphorylation of CREB (cAMP response element binding protein) and MITF (microphthalmia-associated transcription factor) and is thus involved in the melanogenesis and progression of melanoma. CAS is an exosome/microvesicle membrane protein. Tumor cells consistently secrete microvesicles and tumor-derived microvesicles may be accumulated around tumors. Therefore, microvesicle membrane CSE1L may be a potential target for the development of high-efficacy antibody-drug conjugates (ADCs) for cancer therapy. This review will focus on CSE1L expression in cancers, its relationship to Ras/ERK and cAMP/PKA signaling pathways in melanoma development, its potential for the development of ADCs and tumor imaging reagents, and secretory phosphorylated CSE1L for monitoring the emergence of drug resistance in targeted cancer therapy.

Prosurvival function of the cellular apoptosis susceptibility/importin-α1 transport cycle is repressed by p53 in liver cancer

Proteins of the karyopherin superfamily including importins and exportins represent an essential part of the nucleocytoplasmic transport machinery. However, the functional relevance and regulation of karyopherins in hepatocellular carcinoma (HCC) is poorly understood. Here we identified cellular apoptosis susceptibility (CAS, exportin-2) and its transport substrate importin-α1 (imp-α1) among significantly up-regulated transport factor genes in HCC. Disruption of the CAS/imp-α1 transport cycle by RNAi in HCC cell lines resulted in decreased tumor cell growth and increased apoptosis. The apoptotic phenotype upon CAS depletion could be recapitulated by direct knockdown of the X-linked inhibitor of apoptosis (XIAP) and partially reverted by XIAP overexpression. In addition, XIAP and CAS mRNA expression levels were correlated in HCC patient samples (r=0.463; P<0.01), supporting the in vivo relevance of our findings. Furthermore, quantitative mass spectrometry analyses of murine HCC samples (p53-/- versus p53+/+) indicated higher protein expression of CAS and imp-α1 in p53-/- tumors. Consistent with a role of p53 in regulating the CAS/imp-α1 transport cycle, we observed that both transport factors were repressed upon p53 induction in a p21-dependent manner.

CONCLUSION

The CAS/imp-α1 transport cycle is linked to XIAP and is required to maintain tumor cell survival in HCC. Moreover, CAS and imp-α1 are targets of p53-mediated repression, which represents a novel aspect of p53's ability to control tumor cell growth in hepatocarcinogenesis.

Biological significance of the importin-β family-dependent nucleocytoplasmic transport pathways

Importin-β family proteins (Imp-βs) are nucleocytoplasmic transport receptors (NTRs) that import and export proteins and RNAs through the nuclear pores. The family consists of 14-20 members depending on the biological species, and each member transports a specific group of cargoes. Thus, the Imp-βs mediate multiple, parallel transport pathways that can be regulated separately. In fact, the spatiotemporally differential expressions and the functional regulations of Imp-βs have been reported. Additionally, the biological significance of each pathway has been characterized by linking the function of a member of Imp-βs to a cellular consequence. Connecting these concepts, the regulation of the transport pathways conceivably induces alterations in the cellular physiological states. However, few studies have linked the regulation of an importin-β family NTR to an induced cellular response and the corresponding cargoes, despite the significance of this linkage in comprehending the biological relevance of the transport pathways. This review of recent reports on the regulation and biological functions of the Imp-βs highlights the significance of the transport pathways in physiological contexts and points out the possibility that the identification of yet unknown specific cargoes will reinforce the importance of transport regulation.

MIR-137 suppresses growth and invasion, is downregulated in oligodendroglial tumors and targets CSE1L

MicroRNA-137 (miR-137) expression has been reported to be decreased in astrocytic tumors in two expression profiling studies but its role in the pathogenesis of oligodendroglial tumors is still limited. In this study, we demonstrate that miR-137 expression is significantly downregulated in a cohort of 35 oligodendroglial tumors and nine glioma cell lines compared with normal brains. Lower miR-137 expression is associated with shorter progressive-free survival and overall survival. Restoration of miR-137 expression in an oligodendroglial cells TC620, and also glioblastoma cells of U87 and U373 significantly suppressed cell growth, anchorage-independent growth, as well as invasion. Demethylation and deacetylation treatments resulted in upregulation of miR-137 expression in TC620 cells. In silico analysis showed that CSE1 chromosome segregation 1-like (yeast) (CSE1L) is a potential target gene of miR-137. Luciferase reporter assay demonstrated that miR-137 negatively regulates CSE1L by interaction between miR-137 and complementary sequences in the 3' UTR of CSE1L. Immunohistochemistry revealed that CSE1L is upregulated in oligodendroglial tumors. Knockdown of CSE1L resulted in similar outcomes as overexpressing miR-137 in oligodendroglioma cells and glioblastoma cells. Overall, our data suggest that miR-137 regulates growth of glioma cells and targets CSE1L, providing further understanding in the tumorigenesis of gliomas.

CSE1L modulates Ras-induced cancer cell invasion: correlation of K-Ras mutation and CSE1L expression in colorectal cancer progression

BACKGROUND

Ras plays an important role in colorectal cancer progression. CSE1L (chromosome segregation 1-like) gene maps to 20q13, a chromosomal region that correlates with colorectal cancer development. We investigated the association of CSE1L with Ras in colorectal cancer progression.

METHODS

The effect of CSE1L on metastasis-stimulating activity of Ras was studied in an animal model with tumor cells expressing CSE1L-specific shRNA and v-H-Ras. CSE1L expression was evaluated by the immunohistochemical analysis of 127 surgically resected colorectal tumors. K-Ras mutations were analyzed by direct sequencing.

RESULTS

CSE1L knockdown reduced Ras-induced metastasis of B16F10 melanoma cells in C57BL/6 mice. v-H-Ras expression altered the cellular trafficking of CSE1L and increased CSE1L secretion. Most colorectal tumors were positive for CSE1L staining (98.4%, 125 of 127). Colorectal tumors with K-Ras mutation or high cytoplasmic CSE1L expression were correlated with T status (depth of tumor penetration; P = .004), stage (P = .004), and lymph node metastasis (P = .019).

CONCLUSIONS

CSE1L may be a target for treating Ras-associated tumors. Analysis of K-Ras mutation and CSE1L expression may provide valuable clinical and pathological information to aid in the determination of treatment options for colorectal cancer.

CSE1L, a novel microvesicle membrane protein, mediates Ras-triggered microvesicle generation and metastasis of tumor cells

Tumor-derived microvesicles are rich in metastasis-related proteases and play a role in the interactions between tumor cells and tumor microenvironment in tumor metastasis. Because shed microvesicles may remain in the extracellular environment around tumor cells, the microvesicle membrane protein may be the potential target for cancer therapy. Here we report that chromosome segregation 1-like (CSE1L) protein is a microvesicle membrane protein and is a potential target for cancer therapy. v-H-Ras expression induced extracellular signal-regulated kinase (ERK)-dependent CSE1L phosphorylation and microvesicle biogenesis in various cancer cells. CSE1L overexpression also triggered microvesicle generation, and CSE1L knockdown diminished v-H-Ras-induced microvesicle generation, matrix metalloproteinase (MMP)-2 and MMP-9 secretion and metastasis of B16F10 melanoma cells. CSE1L was preferentially accumulated in microvesicles and was located in the microvesicle membrane. Furthermore, anti-CSE1L antibody-conjugated quantum dots could target tumors in animal models. Our findings highlight a novel role of Ras-ERK signaling in tumor progression and suggest that CSE1L may be involved in the "early" and "late" metastasis of tumor cells in tumorigenesis. Furthermore, the novel microvesicle membrane protein, CSE1L, may have clinical utility in cancer diagnosis and targeted cancer therapy.

Cellular apoptosis susceptibility (chromosome segregation 1-like, CSE1L) gene is a key regulator of apoptosis, migration and invasion in colorectal cancer

Cellular apoptosis susceptibility (chromosome segregation 1-like, CSE1L) gene maps to chromosomal region 20q13.13, a region frequently amplified in solid tumours. In this study, we investigated the roles played by CSE1L in colorectal cancer by examining CSE1L expression and clinico-pathological parameters in colorectal cancer and investigating the effect of CSE1L on the viability, adhesion and migration of colorectal cancer cells. RT-PCR showed that CSE1L mRNA was over-expressed in colorectal cancer. CSE1L depletion by knock-down with CSE1L-specific siRNA significantly reduced viability in HCT116 cells (p = 0.004) and SW480 cells (p = 0.003) whilst significantly increasing the proportion of apoptotic HCT116 cells (p < 0.001) and SW480 cells (p < 0.001). Furthermore, CSE1L depletion significantly reduced the adhesive capacity of HCT116 (p = 0.003) and SW480 cells (p = 0.004). Analysis by qRT-PCR following CSE1L siRNA treatment of HCT116 and SW480 cells showed significant modulation of key apoptotic (p53, p73 and BAK) and adhesive (E-cadherin, Ep-CAM and ICAM-1) molecules. Immunohistochemistry of a colorectal cancer tissue microarray showed that CSE1L had a significantly increased level in colorectal cancer compared to normal colorectal epithelium (p < 0.001). There were significant decreases in both nuclear (p = 0.006) and cytoplasmic (p = 0.003) staining of CSE1L in tumours with lymph node metastasis (stage 3 tumours) compared with lymph node-negative tumours (stage 1 and 2 tumours). In lymph node-negative patients, poor survival was associated with increased CSE1L cytoplasmic expression (p = 0.042). These results indicate that CSE1L is associated with viability and apoptosis, cellular adhesion and invasion, thus implicating CSE1L in the progression of colorectal cancer.

Cellular apoptosis susceptibility (CSE1L/CAS) protein in cancer metastasis and chemotherapeutic drug-induced apoptosis

The cellular apoptosis susceptibility (CSE1L/CAS) protein is highly expressed in cancer, and its expression is positively correlated with high cancer stage, high cancer grade, and worse outcomes of patients. CSE1L (or CAS) regulates chemotherapeutic drug-induced cancer cell apoptosis and may play important roles in mediating the cytotoxicities of chemotherapeutic drugs against cancer cells in cancer chemotherapy. CSE1L was originally regarded as a proliferation-associated protein and was thought to regulate the proliferation of cancer cells in cancer progression. However, the results of experimental studies showed that enhanced CSE1L expression is unable to increase proliferation of cancer cells and CSE1L regulates invasion and metastasis but not proliferation of cancer cells. Recent studies revealed that CSE1L is a secretory protein, and there is a higher prevalence of secretory CSE1L in the sera of patients with metastatic cancer. Therefore, CSE1L may be a useful serological marker for screening, diagnosis and prognosis, assessment of therapeutic responses, and monitoring for recurrence of cancer. In this paper, we review the expression of CSE1L in cancer and discuss why CSE1L regulates the invasion and metastasis rather than the proliferation of cancer.

Gene expression: protein interaction systems network modeling identifies transformation-associated molecules and pathways in ovarian cancer

Multiple, dissimilar genetic defects in cancers of the same origin contribute to heterogeneity in tumor phenotypes and therapeutic responses of patients, yet the associated molecular mechanisms remain elusive. Here, we show at the systems level that serous ovarian carcinoma is marked by the activation of interconnected modules associated with a specific gene set that was derived from three independent tumor-specific gene expression data sets. Network prediction algorithms combined with preestablished protein interaction networks and known functionalities affirmed the importance of genes associated with ovarian cancer as predictive biomarkers, besides "discovering" novel ones purely on the basis of interconnectivity, whose precise involvement remains to be investigated. Copy number alterations and aberrant epigenetic regulation were identified and validated as significant influences on gene expression. More importantly, three functional modules centering on c-Myc activation, altered retinoblastoma signaling, and p53/cell cycle/DNA damage repair pathways have been identified for their involvement in transformation-associated events. Further studies will assign significance to and aid the design of a panel of specific markers predictive of individual- and tumor-specific pathways. In the parlance of this emerging field, such networks of gene-hub interactions may define personalized therapeutic decisions.

Cell cycle-related kinase supports ovarian carcinoma cell proliferation via regulation of cyclin D1 and is a predictor of outcome in patients with ovarian carcinoma

Our previous study has suggested that the cell cycle-related kinase (CCRK) is a putative candidate oncogene in glioblastoma tumorigenesis. The potential oncogenic role of CCRK and its clinical/prognostic significance, however, in ovarian carcinoma are unclear. In this study, CCRK expression was examined by immunohistochemistry in a series of ovarian carcinoma tissues. Overexpression of CCRK was detected in 53% of the ovarian carcinomas, and it was positively correlated with an ascending histological grade and/or advanced clinical stage of the disease (p < 0.05). In addition, overexpression of CCRK in ovarian carcinoma was determined to be a strong and an independent predictor of short overall survival (p < 0.05). In ovarian carcinoma cells, CCRK knockdown by RNAi led to a G1 phase cell cycle arrest, while CCRK overexpression by stable transfection of CCRK-containing plasmid pcDNA-CCRK promoted cell proliferation in vitro and tumor growth in vivo. In addition, CCRK knockdown was found to reduce cyclin D1 expression. Consistently, CCRK overexpression increased cyclin D1 expression, and furthermore, a significant correlation between expression of CCRK and cyclin D1 in ovarian carcinomas was observed (p < 0.001). These findings suggest a potential important role of CCRK in the control of cell proliferation via regulation of cyclin D1 expression, and the overexpression of CCRK, as detected by immunohistochemistry, is an independent molecular marker for shortened survival time of patients with ovarian carcinoma.

Integrated genome-wide DNA copy number and expression analysis identifies distinct mechanisms of primary chemoresistance in ovarian carcinomas

PURPOSE

A significant number of women with serous ovarian cancer are intrinsically refractory to platinum-based treatment. We analyzed somatic DNA copy number variation and gene expression data to identify key mechanisms associated with primary resistance in advanced-stage serous cancers.

EXPERIMENTAL DESIGN

Genome-wide copy number variation was measured in 118 ovarian tumors using high-resolution oligonucleotide microarrays. A well-defined subset of 85 advanced-stage serous tumors was then used to relate copy number variation to primary resistance to treatment. The discovery-based approach was complemented by quantitative-PCR copy number analysis of 12 candidate genes as independent validation of previously reported associations with clinical outcome. Likely copy number variation targets and tumor molecular subtypes were further characterized by gene expression profiling.

RESULTS

Amplification of 19q12, containing cyclin E (CCNE1), and 20q11.22-q13.12, mapping immediately adjacent to the steroid receptor coactivator NCOA3, was significantly associated with poor response to primary treatment. Other genes previously associated with copy number variation and clinical outcome in ovarian cancer were not associated with primary treatment resistance. Chemoresistant tumors with high CCNE1 copy number and protein expression were associated with increased cellular proliferation but so too was a subset of treatment-responsive patients, suggesting a cell-cycle independent role for CCNE1 in modulating chemoresponse. Patients with a poor clinical outcome without CCNE1 amplification overexpressed genes involved in extracellular matrix deposition.

CONCLUSIONS

We have identified two distinct mechanisms of primary treatment failure in serous ovarian cancer, involving CCNE1 amplification and enhanced extracellular matrix deposition. CCNE1 copy number is validated as a dominant marker of patient outcome in ovarian cancer.

Integrated genome-wide DNA copy number and expression analysis identifies distinct mechanisms of primary chemoresistance in ovarian carcinomas

PURPOSE

A significant number of women with serous ovarian cancer are intrinsically refractory to platinum-based treatment. We analyzed somatic DNA copy number variation and gene expression data to identify key mechanisms associated with primary resistance in advanced-stage serous cancers.

EXPERIMENTAL DESIGN

Genome-wide copy number variation was measured in 118 ovarian tumors using high-resolution oligonucleotide microarrays. A well-defined subset of 85 advanced-stage serous tumors was then used to relate copy number variation to primary resistance to treatment. The discovery-based approach was complemented by quantitative-PCR copy number analysis of 12 candidate genes as independent validation of previously reported associations with clinical outcome. Likely copy number variation targets and tumor molecular subtypes were further characterized by gene expression profiling.

RESULTS

Amplification of 19q12, containing cyclin E (CCNE1), and 20q11.22-q13.12, mapping immediately adjacent to the steroid receptor coactivator NCOA3, was significantly associated with poor response to primary treatment. Other genes previously associated with copy number variation and clinical outcome in ovarian cancer were not associated with primary treatment resistance. Chemoresistant tumors with high CCNE1 copy number and protein expression were associated with increased cellular proliferation but so too was a subset of treatment-responsive patients, suggesting a cell-cycle independent role for CCNE1 in modulating chemoresponse. Patients with a poor clinical outcome without CCNE1 amplification overexpressed genes involved in extracellular matrix deposition.

CONCLUSIONS

We have identified two distinct mechanisms of primary treatment failure in serous ovarian cancer, involving CCNE1 amplification and enhanced extracellular matrix deposition. CCNE1 copy number is validated as a dominant marker of patient outcome in ovarian cancer.

Epidermal growth factor receptor expression in serous ovarian carcinoma: an immunohistochemical study with galectin-3 and cyclin D1 and outcome

This study investigated the expression of epidermal growth factor receptor (EGFR), galectin-3 and cyclin D1 in a cohort of ovarian serous carcinomas with regard to outcome and clinicopathologic parameters. Formalin-fixed paraffin-embedded archival tissues of fifty ovarian serous carcinomas were stained with anti-bodies to EGFR, Gal-3, and cyclin D1 by automated immunohistochemistry. Additionally, 10 benign serous cystadenomas and 10 typical serous borderline ovarian tumors were included in the study. Immunostaining was scored with regard to quantity and intensity of positively stained nuclei. Staining patterns were recorded. The EGFR expression was scored negative in all serous cystadenomas and serous borderline ovarian tumors. Membranous and cytoplasmic EGFR immunoreactivity was determined in 64% of ovarian serous carcinomas; it was related to high grade (P=0.0005) and poor outcome (P=0.0137) but not with stage (P=0.5118). Galectin-3 and cyclin D1 immunostaining decreased from serous cystadenomas and serous borderline ovarian tumors to the carcinomas significantly (P=0.0022 and P=0.0083, respectively). Galectin-3 immunostaining of any pattern (nuclear and cytoplasmic as well as merely cytoplasmic taken together) was not related to grade or stage in cancers; mere cytoplasmic expression was associated with poor outcome (P=0.0097). Cyclin D1 immunoreactivity in predominantly nuclear pattern was increased in low-grade carcinomas (P=0.0378) but was not related to stage and outcome (P=0.6578 and P=0.0675, respectively). This study indicates that with regard to EGFR and cytoplasmic galectin-3 immunoexpression, multiple marker testing may be an adjunct in the identification of high-risk ovarian serous cancers.

Multiple roles of the candidate oncogene ZNF217 in ovarian epithelial neoplastic progression

The transcription factor ZNF217 is often amplified in ovarian cancer, but its role in neoplastic progression is unknown. We introduced ZNF217-HA by adenoviral and retroviral infection into normal human ovarian surface epithelial cells (OSE), i.e., the source of ovarian cancer, and into SV40 Tag/tag expressing, p53/pRB-deficient OSE with extended but finite life spans (IOSE). In OSE, ZNF217-HA reduced cell-substratum adhesion and accelerated loss of senescent cells, but caused no obvious proneoplastic changes. In contrast, ZNF217-HA transduction into IOSE yielded two permanent lines, I-80RZ and I-144RZ, which exhibited telomerase activity, stable telomere lengths, anchorage independence and reduced serum dependence, but were not tumorigenic in SCID mice. This immortalization required short-term EGF treatment near the time of crisis. The permanent lines were EGF-independent, but ZNF217-dependent since siRNA to ZNF217 inhibited anchorage independence and arrested growth. Array CGH revealed genomic changes resembling those of ovarian carcinomas, such as amplicons at 3q and 20q, and deletions at 4q and 18, associated with underexpressed annexin A10, N-cadherin, desmocollin 3 and PAI-2, which have been reported as tumor suppressors. The lines overexpressed EEF1A2, SMARA3 and STAT1 and underexpressed other oncogenes, tumor suppressors and extracellular matrix/adhesion genes. The results implicate ZNF217 as an ovarian oncogene, which is detrimental to senescing normal OSE cells but contributes to neoplastic progression in OSE with inactivated p53/RB. The resemblance of the genomic changes in the ZNF217-overexpressing lines to ovarian carcinomas provides a unique model to investigate interrelationships between these changes and ovarian neoplastic phenotypes.

Tissue array analysis of expression microarray candidates identifies markers associated with tumor grade and outcome in serous epithelial ovarian cancer

Molecular profiling is a powerful approach to identify potential clinical markers for diagnosis and prognosis as well as providing a better understanding of the biology of epithelial ovarian cancer. On the basis of the analysis of HuFL expression data, we have previously identified genes that distinguish low malignant potential and invasive serous epithelial ovarian tumors. In this study, we used immunohistochemistry to monitor a subset of differently expressed candidates (Ahr, Paep, Madh3, Ran, Met, Mek1, Ccne1, Ccd20, Cks1 and Cas). A tissue array composed of 244 serous tumors of different grades (0-3) and stages (I-IV) was used in this analysis. All markers assayed presented differential protein expression between serous tumors of low and high grade. Significant differences in Ccne1 and Ran expression were observed in a comparison of low malignant potential and grade 1 tumor samples (p<0.01). In addition, irrespective of the grade, Ccne1, Ran, Cdc20 and Cks1 showed significant differences of expression in association with the clinical stage of disease. While high level of Ccne1 have previously been associated with poor outcomes, here we found that high level of either Ran or Cdc20 appear to be more tightly associated with a poor prognosis (p<0.001, 0.03, respectively). The application of these biomarkers in both the initial diagnosis and prognostic attributes of patients with epithelial ovarian tumors should prove to be useful in patient management.

Discrimination between serous low malignant potential and invasive epithelial ovarian tumors using molecular profiling

Tumors of low malignant potential (LMP) represent 20% of epithelial ovarian cancers (EOCs) and are associated with a better prognosis than the invasive tumors (TOV). Defining the relationship between LMPs and TOVs remains an important goal towards understanding the molecular pathways that contribute to prognosis, as well as providing molecular markers, for these EOCs. To this end, DNA microarray analyses were performed either in a primary culture or a tumor tissue model system and selected candidate genes showing a distinctive expression profile between LMPs and TOVs were identified using a class prediction approach based on three statistical methods of analysis. Both model systems appear relevant as candidate genes identified by either model allowed the proper reclassification of samples as either LMPs or TOVs. Selected candidate genes (CAS, CCNE1, LGALS8, ITGbeta3, ATP1B1, FLIP, KRT7 and KRT19) were validated by real-time quantitative PCR analysis and show differential expression between LMPs and TOVs. Immunohistochemistry analyses showed that the two tumor classes were distinguishable by their expression of CAS, TNFR1A, FLIP, CKS1 and CCNE1. These results define signature patterns for gene expression of LMPs and TOVs and identify gene candidates that warrant further study to deepen our understanding of the biology of EOC.

Association of cyclin D1, p16 and retinoblastoma protein expressions with prognosis and metastasis of gallbladder carcinoma

AIM: To investigate the role of cyclin D1, p16 and retinoblastoma in cancerous process of gallbladder carcinomas and to assess the relation between cyclin D1, p16, Rb and the biological characteristics of gallbladder carcinoma.

METHODS: Forty-one gallbladder carcinoma, 7 gallbladder adenoma and 14 chronic cholecystitis specimens were immunohistochemically and histopathologically investigated for the relation of cyclin D1, p16 and Rb with Nevin staging and pathologic grading.

RESULTS: The expression rates of abnormal cyclin D1 in gallbladder carcinoma (68.3%)and gallbladder adenoma(57.1%) were significantly higher than those in chronic cholecystitis (7.1%) (P<0.05). No significant difference was found both among the pathological grades G₁, G₂ and G₃ and among Nevin stagings S₁-S₂, S₃ and S₄-S₅ of gallbladder carcinoma. The positive rates of p16 (48.8%) and Rb (58.5%) in gallbladder carcinoma were significantly lower compared to those in adenoma (100.0%) and cholecystitis (100.0%) (P<0.05). The positive rates of p16 and Rb in Nevin stagings S₁-S₂ (80.0% and 90.0%) and S₃ (46.2% and 61.5%) gallbladder carcinomas were significantly higher than those in S₄-S₅ (33.3% and 38.8%) (P<0.05), and those in pathologic grades G₁ (54.5% and 81.8%) and G₂ (50.0% and 62.5%) gallbladder carcinoma were significantly higher than those in G₃ (28.6% and 35.7%) (P<0.05). The protein expression of p16 and Rb had a negative-correlation in gallbladder carcinoma (r = -0.2993, P<0.05), and this negative-correlation was correlated with Nevin staging (P<0.05). Moreover, the protein expression of p16 and cyclin D1 had a negative-correlation in gallbladder carcinoma (r = -0.9417, P<0.05).

CONCLUSION: Cyclin D1 may play a role in the early stage of gallbladder carcinoma. Mutation of p16 and Rb genes might be correlated with progression of gallbladder carcinoma. Analysis of p16 and Rb can estimate the prognosis of gallbladder carcinoma. Expression of p16 and Rb may be correlated with Nevin staging and pathologic grading in gallbladder carcinoma.

Association of 20q13.2 copy number changes with the advanced stage of ovarian cancer—tissue microarray analysis

Overrepresentations in 20q have been reported in a number of ovarian cancers by comparative genomic hybridization. In order to study the relation of the increased copy number of 20q13.2 with tumor phenotype in ovarian cancer, we applied FISH on a tissue microarray. The TMA technology enables us to analyze a large number of different malignancy, histology, stage and grade tumors. Overall, the frequency of 20q13.2 alterations in epithelial ovarian cancer was 25.50% (10.74% gains and 14.76% amplifications). There was not statistically significant difference between the frequencies of 20q13.2 copy number changes in different grade tumors. The frequency of gains and amplifications increased significantly from stage I to stage II to stage III tumors. Our results showed strong association between increases 20q13.2 copies and advanced tumor stage. We concluded that genetic alterations in 20q13.2 may be of prognostic significance for stage progression of the ovarian cancer.

Overexpression of Cyclin D1 Is Associated with Poor Survival in Epithelial Ovarian Cancer

OBJECTIVE

In order to assess the prognostic role of the cell-cycle regulator cyclin D1 in epithelial ovarian cancer, 70 patients have been studied during an observation period of 8 years.

METHODS

The cyclin D1 protein content was analyzed by Western blotting, and classed as negative, positive and highly positive by densitometric scanning. The relationship between cyclin D1 expression and clinicopathological variables was determined. Univariate and multivariate survival analyses were also carried out.

RESULTS

Patients with highly positive cyclin D1 tumors had shorter overall survival than patients with positive cyclin D1 (median survival 31 vs. 49 months; p = 0.058). Furthermore, in patients with stage III/IV tumors and residual disease greater than 2 cm, cyclin D1 expression significantly influenced clinical outcome (p = 0.047 and 0.040, respectively). In the Cox's regression model, cyclin D1 expression and residual disease were identified as the most important predictors of survival (p = 0.016 and 0.002, respectively). In patients with high cyclin D1 expression and residual disease after debulking surgery greater than 2 cm, the relative risks of death were to 2.48 and 3.7, respectively, compared to their correspondent counterparts.

CONCLUSION

The overexpression of cyclin D1 is significantly related to a more aggressive tumor phenotype and poor prognosis in ovarian carcinoma.