Maspin expression in epithelial ovarian cancer and associations with poor prognosis: A Gynecologic Oncology Group study

SERPINB11 Expression Is Associated With Prognosis of High-grade Serous and Clear Cell Carcinoma of the Ovary

BACKGROUND/AIM

To evaluate the role of serine protease inhibitor B11 (SERPINB11) expression as a prognostic biomarker in high-grade serous carcinoma (HGSC) and clear cell carcinoma of the ovary (CCC).

MATERIALS AND METHODS

We obtained tumor tissues from patients with HGSC (n=145) and CCC (n=59). We evaluated immunohistochemically the expression of SERPINB11 and investigated whether SERPINB11 expression affects platinum-resistance and the prognosis of HGSC and CCC.

RESULTS

High expression of SERPINB11 was more common in CCC than in HGSC (57.6% vs. 28.3%; p<0.01), and SEPRINB11 expression did not correlate with platinum-resistance of HGSC and CCC. High expression of SERPINB11 was associated with worse progression-free survival and overall survival with marginal significance in HGSC; no relation between SERPINB11 expression and the prognosis of CCC was found.

CONCLUSION

SERPINB11 expression maybe a prognostic biomarker for HGSC.

Prognostic role of maspin expression in patients with cervical dysplasia and cervical cancer

AIM

Mammary serine protease inhibitor (maspin) acts as a tumor suppressor through the inhibition of cancer cell invasion and metastasis. Paradoxically, maspin levels are increased in some types of malignant cells. The aim of this study was to investigate the maspin expression in cervical dysplasia and cervical cancer, and to analyze its' relation with survival.

METHODS

Maspin expression was detected by immunohistochemistry using labeled streptavidin biotin method to determine cytoplasmic and nuclear maspin expressions in cervical intraepithelial neoplasia grade 1 (CIN1), cervical intraepithelial neoplasia grade 2 (CIN2), cervical intraepithelial neoplasia grade 3 (CIN3) and cervical cancer.

RESULTS

A total of 89 patients with CIN (29 cases of CIN1, 30 cases of CIN2 and 30 cases of CIN3), and 27 patients with cervical cancer were included to the study. 7.8% of the patients with CIN had maspin staining positivity. On the other hand maspin staining was positive in 20 of 27 patients (74.1%) with cervical carcinoma (P = 0.001). Of these patients 20 (100%) had cytoplasmic, and 8 (40%) had nuclear maspin staining positivity. Cytoplasmic maspin immunoreactive scores were found to be significantly higher in carcinoma group when compared to the patients with CIN1/3 (respectively; P = 0.01, P = 0.02). No difference was noted for nuclear maspin expression. Significant overall survival advantage was detected for patients with nuclear maspin staining (P = 0.03).

CONCLUSION

The current study shows that nuclear maspin expression is related with better overall survival in cervical cancer. Maspin staining can be a useful diagnostic marker to discriminate cervical intraepithelial neoplasia from cervical carcinoma.

Mammary serine protease inhibitor and CD138 immunohistochemical expression in ovarian serous and clear cell carcinomas

This study aims to investigate the immunohistochemical expression of mammary serine protease inhibitor (maspin) and CD138 in primary ovarian high-grade serous carcinomas (HGSC) as compared to low-grade serous carcinomas (LGSC) and clear cell carcinomas and investigate if the studied markers have a correlation to International Federation of Gynaecology and Obstetrics (FIGO) stage, Ki67 proliferation index, and to each other. Maspin cellular location varied significantly between studied groups with only nuclear expression seen in 46.7 % of LGSC group, mixed nuclear and cytoplasmic in 13.3, 28.6, and 20 % of LGSC, HGSC, and clear cell carcinoma, respectively, and was only cytoplasmic in 26.7, 71.4, and 80 % of LGSC, HGSC, and clear cell carcinoma, respectively. Mean maspin and CD138 counts were significantly higher in HGSC and clear cell carcinoma compared to LGSC. Both maspin and CD138 scores varied significantly between studied groups and were positively correlated with adverse prognostic factors in studied carcinomas including FIGO stage and Ki67 proliferation index. Besides, both maspin and CD138 had significant correlation to each other. These findings suggest that epithelial cytoplasmic expression of maspin and CD138 may have a significant role in tumorigenesis in ovarian high-grade serous carcinomas and clear cell carcinomas; these markers may regulate tumor cell proliferation, and their significant correlation to each other may suggest that CD138 probably induces maspin expression to protect tumor growth factors from being lysed by proteolytic enzymes.

Mutation or loss of p53 differentially modifies TGFβ action in ovarian cancer

Ovarian cancer is the most lethal gynecological disease affecting women in the US. The Cancer Genome Atlas Network identified p53 mutations in 96% of high-grade serous ovarian carcinomas, demonstrating its critical role. Additionally, the Transforming Growth Factor Beta (TGFβ) pathway is dysfunctional in various malignancies, including ovarian cancer. This study investigated how expression of wild-type, mutant, or the absence of p53 alters ovarian cancer cell response to TGFβ signaling, as well as the response of the ovarian surface epithelium and the fallopian tube epithelium to TGFβ. Only ovarian cancer cells expressing wild-type p53 were growth inhibited by TGFβ, while ovarian cancer cells that were mutant or null p53 were not. TGFβ induced migration in p53 null SKOV3 cells, which was not observed in SKOV3 cells with stable expression of mutant p53 R273H. Knockdown of wild-type p53 in the OVCA 420 ovarian cancer cells enhanced cell migration in response to TGFβ. Increased protein expression of DKK1 and TMEPAI, two pro-invasive genes with enhanced expression in late stage metastatic ovarian cancer, was observed in p53 knockdown and null cells, while cells stably expressing mutant p53 demonstrated lower DKK1 and TMEPAI induction. Expression of mutant p53 or loss of p53 permit continued proliferation of ovarian cancer cell lines in the presence of TGFβ; however, cells expressing mutant p53 exhibit reduced migration and decreased protein levels of DKK1 and TMEPAI.

Maspin: molecular mechanisms and therapeutic implications

Maspin, a non-inhibitory member of the serine protease inhibitor superfamily, has been characterized as a tumor suppressor gene in multiple cancer types. Among the established anti-tumor effects of Maspin are the inhibition of cancer cell invasion, attachment to extracellular matrices, increased sensitivity to apoptosis, and inhibition of angiogenesis. However, while significant experimental data support the role of Maspin as a tumor suppressor, clinical data regarding the prognostic implications of Maspin expression have led to conflicting results. This highlights the need for a better understanding of the context dependencies of Maspin in normal biology and how these are perturbed in the context of cancer. In this review, we outline the regulation and roles of Maspin in normal and developmental biology while discussing novel evidence and emerging theories related to its functions in cancer. We provide insight into the immense therapeutic potential of Maspin and the challenges related to its successful clinical translation.

Role of maspin in cancer

Maspin (mammary serine protease inhibitor), is a member of the serine protease inhibitor/non-inhibitor superfamily. Its expression is down-regulated in breast, prostate, gastric and melanoma cancers but over-expressed in pancreatic, gallbladder, colorectal, and thyroid cancers suggesting that maspin may play different activities in different cell types. However, maspin expression seems to be correlated with better prognosis in prostate, bladder, lung, gastric, colorectal, head and neck, thyroid and melanoma cancer. In breast and ovarian cancer maspin significance is associated with its subcellular localization: nucleus maspin expression correlates with a good prognosis, whilst in pancreatic cancer it predicts a poor prognosis. Since tumor metastasis requires the detachment and invasion of tumor cells through the basement membrane and stroma, a selectively increased adhesion by the presence of maspin may contribute to the inhibition of tumor metastasis. Furthermore the different position of maspin inside the cell or its epigenetic modifications may explain the different behavior of the expression of maspin between tumors. The expression of maspin might be useful as a prognostic and possibly predictive factor for patients with particular types of cancer and data can guide physicians in selecting therapy. Its expression in circulating tumor cells especially in breast cancer, could be also useful in clinical practice along with other factors, such as age, comorbidities, blood examinations in order to select the best therapy to be carried out. Focusing on the malignancies in which maspin showed a positive prognostic value, therapeutic approaches studied so far aimed to re-activate a dormant tumor suppressor gene by designed transcription factors, to hit the system that inhibits the expression of maspin, to identify natural substances that can determine the activation and the expression of maspin or possible "molecules binds" to introduce maspin in cancer cell and gene therapy capable of up-regulating the maspin in an attempt to reduce primarily the risk of metastasis.Further studies in these directions are necessary to better define the therapeutic implication of maspin.

Implementing an online tool for genome-wide validation of survival-associated biomarkers in ovarian-cancer using microarray data from 1287 patients

The validation of prognostic biomarkers in large independent patient cohorts is a major bottleneck in ovarian cancer research. We implemented an online tool to assess the prognostic value of the expression levels of all microarray-quantified genes in ovarian cancer patients. First, a database was set up using gene expression data and survival information of 1287 ovarian cancer patients downloaded from Gene Expression Omnibus and The Cancer Genome Atlas (Affymetrix HG-U133A, HG-U133A 2.0, and HG-U133 Plus 2.0 microarrays). After quality control and normalization, only probes present on all three Affymetrix platforms were retained (n=22,277). To analyze the prognostic value of the selected gene, we divided the patients into two groups according to various quantile expressions of the gene. These groups were then compared using progression-free survival (n=1090) or overall survival (n=1287). A Kaplan-Meier survival plot was generated and significance was computed. The tool can be accessed online at www.kmplot.com/ovar. We used this integrative data analysis tool to validate the prognostic power of 37 biomarkers identified in the literature. Of these, CA125 (MUC16; P=3.7×10(-5), hazard ratio (HR)=1.4), CDKN1B (P=5.4×10(-5), HR=1.4), KLK6 (P=0.002, HR=0.79), IFNG (P=0.004, HR=0.81), P16 (P=0.02, HR=0.66), and BIRC5 (P=0.00017, HR=0.75) were associated with survival. The combination of several probe sets can further increase prediction efficiency. In summary, we developed a global online biomarker validation platform that mines all available microarray data to assess the prognostic power of 22,277 genes in 1287 ovarian cancer patients. We specifically used this tool to evaluate the effect of 37 previously published biomarkers on ovarian cancer prognosis.

An emerging role for the nuclear localization of maspin in the suppression of tumor progression and metastasis

Maspin, a member of the serpin family of serine protease inhibitors, was originally identified as a tumor suppressor that is expressed in normal mammary epithelial cells but is reduced or absent in breast carcinomas. Early enthusiasm for maspin as a biomarker for disease progression has been tempered by clinical data that associates maspin with favourable outcomes in some studies and poor prognosis in others. Here, we review all of the published clinical studies for maspin in breast and ovarian cancers and propose that the apparent discordance between clinical reports is a consequence of differential cellular distribution of maspin. Indeed, it was thought that an extracellular pool of maspin possessed tumor suppressor activity, acting by inhibiting migration and increasing cell adhesion. Recent evidence from our group and others indicates, however, that the nuclear localization of maspin in cancer cells is necessary for its tumor suppressor activity. We provide additional data here to demonstrate that nuclear-localized maspin binds to chromatin and is required to effectively prevent cells from metastasizing. Our knowledge of other serpins that localize to the nucleus should help to inform future studies of nuclear maspin. Elucidation of the molecular mechanisms regulating the localization and activities of maspin should pave the way for the development of improved diagnostics and therapies for cancer.

The regulation of MASPIN expression in epithelial ovarian cancer: association with p53 status, and MASPIN promoter methylation: a gynecologic oncology group study

OBJECTIVES

To elucidate the regulation of MASPIN expression in epithelial ovarian cancer (EOC) and associations with p53 status and MASPIN promoter methylation.

METHODS

Seven EOC cell lines and 110 advanced stage EOC specimens were analyzed for MASPIN promoter methylation. The cell lines were treated with 5-azacytidine (5-azaC) and evaluated for MASPIN promoter methylation, protein, and mRNA expression. Wild-type (wt) p53 was transiently transfected into the mutant p53 (m p53) SKOV3 cells which were treated with 5-azaC. Phosphor imager analysis quantified the percent methylation of the MASPIN promoter.

RESULTS

Of the 3 MASPIN-low m p53 cell lines 2 had greater than 5% MASPIN methylation whereas only 1 of 4 MASPIN-high wt p53 cell lines had greater than 5% MASPIN methylation. Despite the presence of aberrant MASPIN promoter methylation in SKOV3 cells, wt p53-transfection alone resulted in a 3.3-fold increase in MASPIN mRNA. The combination of 5-azaC and wt p53-transfection produced a 36% reduction in MASPIN promoter methylation and 4.5-fold increase in MASPIN transcription. Among the 110 ovarian cancer specimens analyzed for methylation of the MASPIN promoter, 81.8% were weakly methylated, 14.5% were heavily methylated and 3.6% were fully methylated. There was no relationship between promoter methylation and p53 status or MASPIN protein expression. However, MASPIN protein was 6 times more likely to be detected in cancer specimens that harbor a p53 mutation relative to cancer specimens with a wt p53 gene.

CONCLUSION

The regulation of MASPIN is a complex multifactorial process that may be controlled by both p53-dependent and -independent epigenetic mechanisms.

Expression of Ets-1, Ang-2 and maspin in ovarian cancer and their role in tumor angiogenesis

Background

Various angiogenic regulators are involved in angiogenesis cascade. Transcription factor Ets-1 plays important role in angiogenesis, remodeling of extracellular matrix, and tumor metastasis. Ets-1 target genes involved in various stages of new blood vessel formation include angiopoietin, matrix metalloproteinases (MMPs) and the protease inhibitor maspin.

Methods

We used immunohistochemistry (IHC) to detect the expression of Ets-1, angiopoietin-2 (Ang-2) and maspin in ovarian tumor and analyzed the relationship between the expression of these proteins and the clinical manifestation of ovarian cancer.

Results

Ets-1 expression was much stronger in ovarian cancer compared to benign tumors, but had no significant correlation with other pathological parameters of ovarian cancer. However, Ang-2 and maspin expression had no obvious correlation with pathological parameters of ovarian cancer. Ets-1 had a positive correlation with Ang-2 which showed their close relationship in angiogenesis. Although microvessel density (MVD) value had no significant correlation with the expression of Ets-1, Ang-2 or maspin, strong nuclear expression of maspin appeared to be correlated with high grade and MVD.

Conclusions

The expression of Ets-1, Ang2 and maspin showed close relationship with angiogenesis in ovarian cancer and expression of maspin appeared to be correlated with high grade and MVD. The mechanisms underlying the cross-talk of the three factors need further investigations.

Shift from cytoplasmic to nuclear maspin expression correlates with shorter overall survival in node-negative colorectal cancer

Maspin has been characterized as a potent tumor suppressor in many in vitro and in vivo studies. In contrast, in stage III colon cancer, an association with shorter overall survival as well as sensitivity to chemotherapy was found for cases with nuclear maspin expression. Because 20% of node-negative colorectal cancer cases show a fatal clinical course, we hypothesized that immunohistochemical maspin expression could be of help to identify higher-risk cases. Therefore, we analyzed survival in a study employing 156 cases of stage I/II colorectal cases. Immunohistochemical cytoplasmic and/or nuclear maspin expression was found in 72% and 48% of the cases, respectively. Significant correlations between cytoplasmic expression and high tumor grade (P < .01) and between nuclear expression and tumor budding (P < .001) were shown. No differences concerning overall survival and immunohistochemical maspin expression were found when the complete collective was analyzed. However, evaluation of the pT3 cases revealed a highly significant worse mean overall survival of cases with a combination of nuclear expression and cytoplasmic loss of maspin compared to cases with the opposite expression pattern nuclear loss and cytoplasmic expression (mean overall survival 40 versus 63 months, respectively; P < .001). The other possible combinations (complete positive and complete negative) showed intermediate mean overall survival times with 54 and 49 months, respectively. Our findings suggest a compartment-dependent function of maspin in colorectal cancer, which can be useful in identifying stage II cases with a higher risk for fatal outcome with a possible benefit from adjuvant chemotherapy.

Translational research in the Gynecologic Oncology Group: evaluation of ovarian cancer markers, profiles, and novel therapies

OBJECTIVES

To review the translational research (TR) performed in the Gynecologic Oncology Group (GOG) to evaluate ovarian cancer markers, profiles and novel therapies.

METHODS

Prospective trials with stand alone or embedded TR objectives involving patient and specimen accrual as well as retrospective studies using banked specimens and resources were and continue to be performed in the GOG. Appropriate statistical methods are employed to evaluate associations with clinical characteristics and outcomes including tumor response, adverse events, progression free survival and overall survival.

RESULTS

Highlights are presented for some of the collaborative and multidisciplinary TR conducted with the GOG to evaluate markers, pathway and novel therapeutics in epithelial ovarian, primary peritoneal and/or fallopian tube cancer. For example, in GOG 111, high immunohistochemical (IHC) expression of cyclin E was associated with a shorter median survival (29 versus 35 months) and an increased risk of death (hazard ratio [HR]=1.4, 95% confidence interval [CI]=1.0-2.1, p=0.05). In GOG 114/132, non-detectable immunoblot expression of maspin was associated with debulking status (p=0.034) and an increased risk of disease progression (HR=1.89, 95% CI=1.04-3.45, p=0.038) and death (HR=1.99, 95% CI=1.07-3.69, p=0.030) while high CD105-microvessel density (MVD), but not CD31-MVD in tumor was associated with increased risk of disease progression (HR=1.873, 95% CI=1.102-3.184, p=0.020) but not death. In GOG 172, low IHC expression of BRCA1 was associated with advanced stage (p<0.001), serous histology (p<0.001) and a reduced risk of disease progression (HR=0.64, 95% CI=0.42-0.96) and death (HR=0.51, 95% CI=0.32-0.83) while the CA/AA versus CC genotypes in C8092A in ERCC1 were associated with an increased risk of disease progression (HR=1.44, 95% CI=1.06-1.94, p=0.018) and death (HR=1.50, 95% CI=1.07-2.09, p=0.018).

CONCLUSIONS

The GOG has an extensive TR program that provides clues regarding the molecular and biochemical mechanisms of disease, treatments and outcomes in women with or at risk for a gynecologic malignancy.

Mammaglobin and maspin transcripts in blood may reflect disease progression and the effect of therapy in breast cancer

Detection of residual tumor cells in the circulation can provide prognostic as well as therapeutic information and help in identifying patients at high risk for developing metastases. Maspin and mammaglobin are two molecules that are specifically associated with breast cancer. We looked for mammaglobin and maspin transcripts in the peripheral blood of patients with breast cancer and evaluated their utility as a marker of the response to therapy. Maspin and mammaglobin transcripts were analyzed in 85 breast-cancer patients by nested RT-PCR, prior to and after treatment. Before therapy, 10 patients were found positive for mammaglobin and 20 patients were positive for maspin. In four patients, both transcripts were detected. Immediately following treatment, only one patient was still positive for mammaglobin while maspin transcripts persisted in three patients. Disease progression was observed mainly in patients in whom maspin transcripts were not detectable. Molecular detection of circulating tumor cells during therapy based on analysis for mammaglobin and maspin transcripts is an easy and practical method that can be applied to follow-up patients. We suggest that detection of mammaglobin mRNA is useful to determine the effect of therapy while maspin transcripts may indicate more aggressive disease.

BRCA1 185delAG mutant protein, BRAt, up-regulates maspin in ovarian epithelial cells

OBJECTIVE

Aggressive clinical course and difficult detection of ovarian cancer are major challenges to improving patient survival and necessitate avid investigation into more effective therapeutic approaches. Understanding early molecular and pathological changes in high risk patients, such as BRCA1 mutation carriers, can provide candidates for molecular profiling and novel targets for effective therapies.

METHODS

Using a culture model system for normal human ovarian surface epithelial cells with and without the BRCA1 185delAG frameshift mutation for the truncated protein product, BRAt, we investigated the role of BRAt in enhanced chemosensitivity. We used MTS, Western immunoblot, semi-quantitative RT-PCR, luciferase reporter and siRNA assays, to identify novel downstream targets of BRAt that promote apoptosis following chemotherapeutic treatment.

RESULTS

We identified maspin as a novel downstream target of BRAt. BRAt increases maspin expression with preferential nuclear localization of maspin. Further, Brat-mediated maspin expression is transcriptionally regulated through an AP1 site within the (-520) to (-297) region of the promoter. Lastly, BRAt, enhances chemosensitivity in normal ovarian surface epithelial cells through c-Jun by a mechanism that may involve maspin.

CONCLUSIONS

BRAt-mediated enhanced chemosensitivity correlates clinically with enhanced chemotherapeutic response in BRCA1 mutation carriers. BRAt-mediated maspin expression also correlates with improved prognostic outlook for ovarian tumors with high levels of nuclear maspin. Consequently, understanding early genotypic and phenotypic changes in the context of high risk disease may provide a better understanding of the mechanism of mutation-associated ovarian cancer and provide new targets for therapeutic intervention.

Association between the N-terminally truncated (DeltaN) p63alpha (DeltaNp63alpha) isoform and debulking status, VEGF expression and progression-free survival in previously untreated, advanced stage epithelial ovarian cancer: A Gynecologic Oncology Group study

OBJECTIVES

The Gynecologic Oncology Group (GOG) examined the association between the relative expression of the DeltaNp63alpha isoform and clinicopathologic variables, p53 status, angiogenic markers, progression-free survival (PFS) and overall survival (OS) in epithelial ovarian cancer (EOC).

METHODS

Immunoblot analysis was used to determine the relative expression of DeltaNp63alpha to beta-actin in lysates of frozen primary tumor from women with previously untreated, advanced stage EOC who participated in a GOG specimen banking protocol and a randomized phase III treatment protocol.

RESULTS

DeltaNp63alpha was detected in 49/56 (87.5%) cases with relative expression ranging from 0 to 4.55 (median=0.325). A correlation was observed between the relative expression of DeltaNp63alpha and debulking status (Spearman's correlation coefficient=0.303; p=0.025) and the relative expression of vascular endothelial growth factor (VEGF) (Spearman's correlation coefficient=0.303; p=0.045), but not with p53 status (overexpression or mutation), immunoblot expression of MASPIN, or the relative expression of thrombospondin-1, basic fibroblast growth factor or VEGF receptor-1. A 1.4-fold increase was observed in the risk of disease progression for each unit increase in the relative expression of DeltaNp63alpha using an unadjusted (hazard ratio [HR]=1.459; 95% confidence interval [CI]=1.096-1.942; p=0.010), a full (HR=1.483; 95% CI=1.060-2.076; p=0.021) and a reduced (HR=1.387; 95% CI=1.025-1.877; p=0.034) Cox regression model. The relative expression of DeltaNp63alpha was not associated with OS using an unadjusted, a full or a reduced Cox model.

CONCLUSIONS

The relative expression DeltaNp63alpha appears to be associated with debulking status and the relative expression of VEGF and PFS, and to be an independent prognostic factor for disease progression in EOC.

MASPIN's prognostic role in patients with advanced head and neck carcinoma treated with primary chemotherapy (carboplatin plus vinorelbine) and radiotherapy: preliminary evidence

CONCLUSIONS

Our very preliminary results support the hypothesis that MASPIN expression in primary head and neck squamous cell carcinoma (HNSCC) may be a valuable parameter for predicting patients' responses to a treatment based on carboplatin plus vinorelbine combined with radiotherapy.

OBJECTIVES

The roles of induction chemotherapy and combined chemoradiotherapy in the treatment of locally advanced unresectable HNSCCs have evolved rapidly. MASPIN has a unique tumour-suppressing activity. Experimental evidence has shown that MASPIN suppresses tumour growth, angiogenesis, invasion and metastasis. We investigated the potential prognostic roles of MASPIN and p53 in a series of HNSCCs treated with carboplatin plus vinorelbine combined with radiotherapy.

PATIENTS AND METHODS

Nineteen consecutive stage III or IV HNSCC patients were recruited. The treatment plan consisted of the administration of carboplatin on day 1 and vinorelbine on days 1 and 8. Four weeks later, carboplatin was administered concomitantly with radiation therapy. Expression of MASPIN and p53 was determined immunohistochemically in HNSCC diagnostic biopsies.

RESULTS

A significant inverse relation was found between MASPIN expression and cN staging (p = 0.003). From a prognostic viewpoint, MASPIN expression was directly correlated with chemoradiotherapy response (p = 0.041). Moreover, the log-rank test showed a significant relationship between higher MASPIN expression and longer disease-free survival (p = 0.03), overall survival (p = 0.006) and disease-specific survival (p = 0.007).

Independent prognostic relevance of microvessel density in advanced epithelial ovarian cancer and associations between CD31, CD105, p53 status, and angiogenic marker expression: A Gynecologic Oncology Group study

OBJECTIVES

The aims of this study were to examine prognostic significance of microvessel density (MVD) in previously-untreated, advanced epithelial ovarian cancer (EOC) and explore associations between MVD and factors that affect angiogenesis.

METHODS

MVD was determined by immunohistochemical expression of CD31 or CD105 in tumor sections from 106 women treated on GOG randomized phase III trials. Average MVD hotspots were quantified by light microscopy at high power (x400) and categorized as low (<upper quartile) or high (>or=upper quartile). Immunoblot expression of MASPIN, THBS-1, bFGF, VEGF, VEGFR-1 and p53 status (mutation and overexpression) was previously determined.

RESULTS

Of 106 evaluable cases, 25% exhibited high CD31-MVD (>24.25 vessels/high power field [HPF]) or high CD105-MVD (>19.25 vessels/HPF). After adjusting for age and stratifying by GOG performance status, stage, cell type, grade, debulking status and treatment regimen, high versus low CD105-MVD was associated with increased risk of disease progression (hazard ratio [HR]=1.873; 95% confidence interval [CI]: 1.102-3.184; p=0.020), but not death (HR=1.125; 95% CI: 0.654-1.935; p=0.670) whereas CD31-MVD was not associated with risk of disease progression (HR=1.578; 95% CI=0.918-2.711; p=0.099) or death (HR=1.678; 95% CI=0.957-2.943; p=0.071). CD31-MVD was correlated with CD105-MVD (p=0.001) and MASPIN (p=0.016). Neither CD31-MVD nor CD105-MVD was associated with p53 status, THBS-1, bFGF, VEGF or VEGFR-1.

CONCLUSIONS

High MVD assessed using CD105, a marker of proliferating endothelial cells and neoangiogenesis, but not CD31 a pan-endothelial marker, appeared to be an independent prognostic factor for worse progression-free survival in women with advanced EOC after adjusting for prognostic clinical covariates.

The detection of differentially expressed microRNAs from the serum of ovarian cancer patients using a novel real-time PCR platform

OBJECTIVE

To determine the utility of serum miRNAs as biomarkers for epithelial ovarian cancer.

METHODS

Twenty-eight patients with histologically confirmed epithelial ovarian cancer were identified from a tissue and serum bank. Serum was collected prior to definitive therapy. Fifteen unmatched, healthy controls were used for comparison. Serum was obtained from all patients. RNA was extracted using a derivation of the single step Trizol method. The RNA from 9 cancer specimens was compared to 4 normal specimens with real-time PCR using the TaqMan Array Human MicroRNA panel. Twenty-one miRNAs were differentially expressed between normal and patient serum. Real-time PCR for the 21 individual miRNAs was performed on the remaining 19 cancer specimens and 11 normal specimens.

RESULTS

Eight miRNAs of the original twenty-one were identified that were significantly differentially expressed between cancer and normal specimens using the comparative C(t) method. MiRNAs-21, 92, 93, 126 and 29a were significantly over-expressed in the serum from cancer patients compared to controls (p<.01). MiRNAs-155, 127 and 99b were significantly under-expressed (p<.01). Additionally, miRs-21, 92 and 93 were over-expressed in 3 patients with normal pre-operative CA-125.

CONCLUSION

We demonstrate that the extraction of RNA and subsequent identification of miRNAs from the serum of individuals diagnosed with ovarian cancer is feasible. Real-time PCR-based microarray is a novel and practical means to performing high-throughput investigation of serum RNA samples. miRNAs-21, 92 and 93 are known oncogenes with therapeutic and biomarker potential.

Tumor heterogeneity in ovarian cancer as demonstrated by in vitro chemoresistance assays

OBJECTIVE

Tumor heterogeneity has been demonstrated in solid tumors. In vitro assays were developed in an effort to predict in vivo tumor response to therapy. We compare the in vitro assay results from multiple synchronous tumor samples in primary and recurrent ovarian cancers.

METHODS

38 patients underwent surgery for primary (18) or recurrent (20) ovarian cancer. Two (22) or three (16) samples were obtained per patient and tested using the EDR assay (Oncotech, Inc.). The percentage of Extreme (E), Intermediate (I) and Low (L) drug resistance for each chemotherapy was compared between synchronous specimens.

RESULTS

A total of 92 samples were collected and 787 drug assays were performed. Tumor heterogeneity was seen in 22.4% of all cases, including 18.6% primary and 26.1% recurrent diseases (p=0.01). Two category differences (L vs. E) were seen in 4.1% primary and 11.3% recurrent cases (7.8% of all cases). Overall, an increased frequency in EDR was seen in recurrent disease as compared to primary for all agents tested (22.9% primary vs. 31.6% recurrent, p=0.006). Marked heterogeneity of the drug resistance profiles was seen with paclitaxel as compared with cisplatin/gemcitabine (p=0.03), taxotere (p=0.04) or topotecan (p=0.04). No association was demonstrated between assay results and clinicopathologic parameters collected in this cohort.

CONCLUSIONS

Treatment failure is often attributed to the development of chemoresistance. These results suggest that tumor heterogeneity may play an equally important role in treatment failure. Recurrent lesions exhibit greater heterogeneity and more frequent EDR. These data can influence therapeutic strategy i.e., multiple samples, sequential, or consolidation therapy.

Maspin overexpression correlates with increased expression of vascular endothelial growth factors A, C, and D in human ovarian carcinoma

The vascular endothelial growth factor (VEGF) family, including VEGFA, VEGFC, and VEGFD, plays an essential role in the angiogenesis of both pathologic and nonpathologic conditions. Maspin belongs to the serpin superfamily and has been identified as a tumor suppressor because it inhibits motility, invasion, and angiogenesis. Few studies have compared maspin with VEGF in ovarian carcinoma. Therefore, we investigated the expression and correlation of maspin, VEGFA, VEGFC, and VEGFD with the tumorigenesis of the ovary and clinicopathologic variables. Using immunohistochemistry, we examined maspin, VEGFA, VEGFC, and VEGFD expression in 60 ovarian carcinoma tissues (35 serous papillary carcinomas, 18 endometrioid carcinomas, and 7 primary ovarian mucinous carcinomas). Staining of cells was scored as +2 if more than 50% of the cells were positive, as +1 if less than 50% of the cells were positive, and as negative if none of the cells stained positive. Overexpression of maspin, VEGFC, and VEGFD was significantly associated with high tumor grade (P<.001, P=.004, P<.001, respectively), clinical stage (P=.002, .01, and .001, respectively), the presence of ascites (P<.001, P=.03, and P=.001, respectively), and the presence of metastatic lymph nodes (P=.002, P<.001, and P<.001, respectively). Maspin was correlated with VEGFA (P=.01), VEGFC (P<.001), and VEGFD (P<.001). The VEGFA score was positively correlated with high tumor grade (P=.04), lymphovascular space invasion (LVSI) (P<.001), International Federation of Gynecology and Obstetrics (FIGO) stage (P=.009), maspin, VEGFC (P=.003), and VEGFD (P=.003), but it was not correlated with the presence of ascites and metastatic lymph nodes. Maspin, VEGFC, and VEGFD are expressed in ovarian tumors with a poor prognostic parameters, and seem to play a role in ovarian cancer angiogenesis, progression, and lymph node metastases. Our results indicate that in contrast to most other carcinomas, maspin expression is directly associated with the biological aggressiveness of ovarian carcinoma. These results may offer new insights regarding the role of maspin in ovarian cancer and might also affect the diagnosis and treatment strategies.

Maspin Expression in Oral Squamous Cell Carcinoma

Maspin (mammary serine protease inhibitor) is a member of the serpin superfamily of protease inhibitors and it has a role as a tumor suppressor. Maspin has been reported to be important in processes relevant to tumor growth and metastasis such as cell invasion, angiogenesis, and apoptosis. A high expression of maspin was correlated with better rates of survival and absence of nodal metastases in head and neck squamous cell carcinoma. In contrast, some studies have shown that maspin overexpression is correlated with a poor prognosis in pancreatic and ovarian cancers and in lung adenocarcinoma. The aim of this study was an immunohistochemical evaluation of the maspin expression in oral squamous cell carcinoma and thus 89 patients were evaluated. Maspin expression in oral squamous cell carcinoma was significantly associated with the tumor differentiation grade (chi test: P = 0.0318) and the lymph node status (chi test: P < 0.005), but not with the tumor stage (chi test: P = 0.666). Metastatic involvement of lymph nodes was observed more frequently in maspin-negative cases than in tumors with more than 5% of positive cells (P = 0.0024). The present results confirm that maspin expression predicts a better prognosis in oral squamous cell carcinoma and that maspin probably plays a role in tumor progression.

Prognostic significance of maspin in pancreatic ductal adenocarcinoma: tissue microarray analysis of 223 surgically resected cases

Maspin (SERPINB5), a serine proteinase inhibitor, was first identified as a potential tumor suppressor on the basis of its differential expression between normal mammary epithelial cells and human breast carcinoma cell lines. Recent studies have shown that maspin might be a prognostic tumor marker. Pancreatic ductal adenocarcinoma acquires maspin expression through hypomethylation of the maspin promoter. However, no study has investigated the prognostic significance of maspin expression in pancreatic ductal adenocarcinomas. In this study, we investigated maspin protein expression in a large series of 223 surgically resected pancreatic ductal adenocarcinomas using immunohistochemical staining and high throughput tissue microarrays. Maspin expression was correlated with postoperative survival and other clinicopathologic factors. Maspin was detected in 209 of these 223 (94% cases) pancreatic ductal adenocarcinomas including 39 (18% cases) focal (5-50% tumor cells) and 170 (76% cases) diffuse (>50% tumor cells). Fourteen (or 6% cases) pancreatic ductal adenocarcinomas did not show maspin expression by immunohistochemical staining (<5% tumor cells). Normal ductal epithelium is not labeled with maspin. Overexpression of maspin in pancreatic ductal adenocarcinoma is associated with worse postoperative survival especially in patients whose tumors exhibit diffuse expression of maspin. After adjusting other clinicopathologic factors, maspin expression remains to be an independent adverse prognosticator for postoperative survival. Maspin expression is not associated with patient age, gender, tumor size, tumor pathologic stage, lymph node status, and vascular invasion or perineural invasion. Nuclear labeling of maspin is associated with better tumor differentiation although this staining pattern is not associated with a better prognosis. In addition, maspin overexpression is also observed in 48% low-grade (grades 1a and 1b) pancreatic intraepithelial neoplasias (PanINs) and 78% high-grade (grades 2 and 3) PanINs, suggesting that maspin upregulation occurs early during the multi-step progression model of pancreatic ductal adenocarcinoma.