Paul Speiser

Cyclin gene amplification and overexpression in breast and ovarian cancers: Evidence for the selection of cyclin D1 in breast and cyclin E in ovarian tumors

Evidence of the involvement of cyclin genes in genetic alterations in human cancer is growing. In the present study, we investigated the amplification, in human breast and ovarian cancer, of 5 cyclin genes; cyclin A, cyclin D1, cyclin D2, cyclin D3 and cyclin E. For this purpose, a series of 1,171 breast and 237 ovarian tumors tested for DNA amplification by Southern blotting and a subset of 132 breast and 22 ovarian cancers were analyzed for RNA expression levels by slot‐blot and Northern blotting. In breast tumors, only cyclin D1 was found to be activated in a sizeable fraction of the tumors (amplification 12.6%, overexpression 19%). Cyclin A, D2, D3, and E genes never, or only on rare occasions, showed increased DNA copy numbers and were never found overexpressed at the RNA level. Amplification of cyclin D1 correlated with ER+ breast cancer and the presence of lymph‐node metastasis. Interestingly, we were also able to determine an association with invasive lobular carcinoma. Our data suggest that cyclin D1 activation determines the evolution of a particular subset of estrogen‐responsive tumors. Data obtained in ovarian tumors contrasted with observations in breast cancer. Cyclin D1 DNA amplification was much less frequent in ovarian than in breast tumors (3.3% vs. 12.6%), whereas cyclin E amplification and overexpression were observed in a significant number of cases (12.5% and 18.0% respectively). Cyclin A, cyclin D2 and D3 rarely showed anomalies at the DNA level and were never overexpressed. No clear correlation could be observed between amplification of the cyclin E gene and tumor type, stage or grade in ovarian cancer. Data presented here suggest distinct pathways of cyclin activation in human breast and ovarian cancer.

Vascular endothelial growth factor (VEGF) in human breast cancer : Correlation with disease-free survival

Studies have shown that microvessel density influences breast‐cancer prognosis. Since tumor angiogenesis is considered to be substantially affected by the excretion of vascular endothelial growth factor (VEGF) from tumor cells, we examined whether VEGF concentration is different in malignant and in non‐malignant breast tissue. It was also of interest to discover whether intratumoral VEGF concentration influences disease‐free survival (DFS) of breast‐cancer patients. Analysis is based on 120 tissue specimens taken from breast fibromas (n = 23), normal epithelial breast tissue adjacent to fibromas (n = 8) and invasive breast cancer (n = 89). VEGF concentration was quantified by using an immunoassay. Microvessel density was determined by immunostaining for factor‐VIII‐related antigen. Median VEGF concentration is given in pg/mg protein (25%‐quantile—75%‐quantile) and it was 0 (0–1.8) in normal breast tissue, 9.8 (0.52–43.0) in fibromas and 130.4 (50.8–362.2) in invasive carcinomas. A univariate Cox model revealed that node status, tumor size, estrogen‐receptor concentration, histological grading and microvessel density were prognostic factors for disease‐free survival in breast cancer. We found a significant correlation between VEGF concentration and microvessel count, but VEGF concentration did not significantly influence disease‐free survival. Although VEGF protein was found at a significantly higher concentration in malignant than in non‐malignant tissue, determination of intratumoral VEGF protein by an enzyme immunoassay was not prognostically relevant in our patient population. Int. J. Cancer 74:455–458, 1997.

DNA amplifications at 20q13 and MDM2 define distinct subsets of evolved breast and ovarian tumours.

DNA amplification seems to be particularly frequent in human breast tumours and has been associated with cancer evolution and aggressiveness. Recent data indicate that new events should be added to the list, such as the amplifications at chromosome 20q13 or the MDM2 gene. The present work aimed at determining the incidence and clinicopathological signification of these amplifications in a large series of breast and ovarian tumours. We tested 1371 breast and 179 ovarian tumours by Southern blotting and observed amplification of 20q13 in 5.4% breast and 2.8% ovarian carcinomas, whereas MDM2 was found amplified in 5.3% and 3.8% of breast and ovarian tumours respectively. MDM2 RNA expression levels were analysed in a subset of 57 breast tumours and overexpression was observed in 4/57 (7%) of the tumours. Elevated expression levels coincided with amplification of the gene. In breast cancer, 20q13 and MDM2 amplifications seem to define subsets of aggressive tumours. Indeed, 20q13 was correlated to axillary nodal involvement and occurred preferentially in younger patients (< 50 years). Furthermore, 20q13 correlated, as did MDM2 amplification, to aneuploidy. In parallel, we had also tested our tumour DNAs for amplification of CCND1, ERBB-2 and MYC, which made it possible to test for correlations with 20q13 or MDM2 amplifications. Whereas 20q13 showed a very strong correlation to CCND1 amplification, that of MDM2 was prevalent in MYC-amplified tumours. Interestingly, 20q13 and MDM2 amplifications showed some degree of correlation to each other, which may possibly be owing to the fact that both events occurred preferentially in aneuploid tumours. In ovarian cancer, no statistically significant correlation was observed. However, 20q13 amplification occurred preferentially in stage 3 tumours and MDM2 was correlated to ERBB-2 amplification. This may suggest that in ovarian tumours also, 20q13 and MDM2 amplifications occur in late or aggressive cancers.

Molecular characterization of circulating tumor cells in patients with ovarian cancer improves their prognostic significance — A study of the OVCAD consortium

OBJECTIVE The study aims at identifying novel markers for circulating tumor cells (CTCs) in patients with epithelial ovarian cancer (EOC), and at evaluating their impact on outcome. METHODS Microarray analysis comparing matched EOC tissues and peripheral blood leucocytes (N=35) was performed to identify novel CTC markers. Gene expression of these novel markers and of EpCAM was analyzed using RT-qPCR in blood samples taken from healthy females (N=39) and from EOC patients (N=216) before primary treatment and six months after adjuvant chemotherapy. All samples were enriched by density gradient centrifugation. CTC positivity was defined by over-expression of at least one gene as compared to the healthy control group. RESULTS CTC were detected in 24.5% of the baseline and 20.4% of the follow-up samples, of which two thirds were identified by overexpression of the cyclophilin C gene (PPIC), and just a few by EpCAM overexpression. The presence of CTCs at baseline correlated with the presence of ascites, sub-optimal debulking, and elevated CA-125 and HE-4 levels, whereas CTC during follow-up occurred more often in older and platinum resistant patients. PPIC positive CTCs during follow-up were significantly more often detected in the platinum resistant than in the platinum sensitive patient group, and indicated poor outcome independent from classical prognostic parameters. CONCLUSIONS Molecular characterization of CTC is superior to a mere CTC enumeration or even be the rationale for CTC diagnostics at all. Ultimately CTC diagnostics may lead to more personalized treatment of EOC, especially in the recurrent situation.

Influence of intratumoral basic fibroblast growth factor concentration on survival in ovarian cancer patients

Since basic fibroblast growth factor (bFGF) is considered as a potent mitogen that stimulates the growth of ovarian cancer cells, we evaluated the role of bFGF as a prognostic marker in patients with epithelial ovarian cancer. bFGF was quantified from the tumor cytoplasm of 76 patients with FIGO stage I-III ovarian cancer by a human FGF basic immunoassay (R&D Systems). After a mean follow-up period of 42 months, 50 patients were found to be free of tumor while 26 patients had died of the disease. The median bFGF concentration was 352.9 pg/mg (range 27.4-26600 pg/mg). After dichotomization cytoplasmic expression of bFGF was found to be low in 44 tumors (< or =500 pg/mg) and high in 32 tumors (>500 pg/mg). The probability of overall survival was 38.8 and 58.5% in the low bFGF and high bFGF groups, respectively (log-rank P = 0.0066). In multivariate analysis, residual tumor after initial surgery and bFGF, but not histologic grade or stage of the disease, independently influenced the overall survival probability. Furthermore, tumors with high cytoplasmic expression of bFGF revealed a much greater stromal content. Therefore, we hypothesize that bFGF may induce a fibroblastic response which causes tumors with a high bFGF to be less aggressive than those with less stromal tissue.

ABC transporter gene expression in benign and malignant ovarian tissue.

OBJECTIVE ATP-binding Cassette (ABC) transporters are thought to cause multiple drug resistance (MDR) in various carcinomas. Gene expression data from individual transporters in ovarian cancer tissue is contradictory and also scarce for some of them. RNA levels of a panel of ABC transporters were collected and analyzed to get a more detailed overview which transporters are of importance in resistance to chemotherapeutic agents in ovarian carcinoma. METHODS Real-time PCR was used to determine RNA expression levels of 9 ABC transporters in 50 benign tissue samples and 50 recurrent ovarian cancer samples. Genes exhibiting a significant difference between those two groups were further evaluated in 50 primary cancer samples. Data were analyzed with receiver operating characteristic (ROC) curves and multiple Wilcoxon-Mann-Whitney U-tests with Shaffer correction. RESULTS Gene expression of four transporters (ABCC1, ABCC2, ABCC3, and ABCB3) was significantly elevated in recurrent cancer lesions compared to benign tissue. Expression levels of these 4 ABC transporters were further analyzed in primary ovarian cancer lesions. A significant difference between primary and recurrent tumor tissue was found in all four genes. Changes in gene expression between benign samples and primary lesions were minor and not relevant. CONCLUSIONS Four of the examined ABC transporters are likely to play a role in the MDR of ovarian carcinoma. Gene expression of these transporters seems only up regulated through chemotherapy. The thesis that MDR in ovarian cancer is acquired through therapy itself and not present ab initio is supported by these findings.

Role of TRAP1 and estrogen receptor alpha in patients with ovarian cancer -A study of the OVCAD consortium

BackgroundThe role of the tumor necrosis factor receptor associated protein 1 (TRAP1) – supposed to be involved in protection of cells from apoptosis and oxidative stress – has just started to be investigated in ovarian cancer. TRAP1 has been shown to be estrogen up-regulated in estrogen receptor α (ERα) positive ovarian cancer cells. The clinical impact of TRAP1 is not clear so far and the significance of ERα expression as therapeutic and prognostic marker is still controversial. Therefore, we investigated the importance of TRAP1 together with ERα in regard to clinicopathological parameters, chemotherapy response, and survival.Methods and resultsExpressions of TRAP1 and ERα were evaluated by immunohistochemical staining of tissue microarrays comprised of 208 ovarian cancer samples. TRAP1 was highly expressed in 55% and ERα was expressed in 52% of all cases. High TRAP1 expression correlated significantly with ERα (p < 0.001) but high TRAP1 expression was also found in 42% of ERα negative cases. High TRAP1 expression correlated significantly with favorable chemotherapy-response (HR = 0.48; 95%CI 0.24-0.96, p=0.037) and showed a significant impact on overall survival (OS) (HR = 0.65; 95%CI 0.43-0.99, p = 0.044). ERα expression was a favorable prognostic factor for OS in univariate and multivariate analyses. Interestingly, the combined pattern (ERα positive and/or TRAP1-high) revealed the strongest independent and significant positive influence on OS (HR = 0.41; 95%CI 0.27-0.64).ConclusionImmunohistochemical evaluation of TRAP1 together with ERα provides significant prognostic information. TRAP1 alone is significantly associated with chemotherapy response and overall survival, rendering TRAP1 as interesting scientific and therapeutic target.

Genomic deletions in the BRCA1, BRCA2 and TP53 regions associate with low expression of the estrogen receptor in sporadic breast carcinoma

Sporadic breast carcinoma is associated with multiple genetic alterations. The clinical relevance of these alterations, however, needs further clarification. In the present study we analyzed 266 spontaneously arising breast carcinomas for allelic losses in the BRCA1 and TP53 regions on chromosome 17, the BRCA2 region on chromosome 13, the ATM (mutated in ataxia‐telangiectasia) region on chromosome 11 and on the chromosomal arms 7q and 16q. In addition the following clinical and pathological parameters were evaluated: age at diagnosis, tumor size, presence or absence of regional and distant metastases, hormone‐receptor status, histopathological classification and tumor grading. The analysis of genetic and clinical observations revealed significant associations: absence of expression of the estrogen receptor was linked to a high rate of allelic losses of markers in the BRCA1, TP53 and BRCA2 regions. Expression of the progesterone receptor coincided with allelic loss on the long arm of chromosome 16. High‐grade malignant lesions and ductal differentiation were frequently associated with allelic losses in the proximal portion of chromosome 17q. The accumulation of multiple allelic deletions was linked to high‐grade malignant tumors, to tumor size, and to loss of expression of the estrogen receptor. Our data point to a relationship between clinically relevant prognostic factors and specific genomic deletions in the BRCA1, BRCA2 and TP53 region. Int. J. Cancer 74:322‐325, 1997.

Validating the impact of a molecular subtype in ovarian cancer on outcomes: A study of the OVCAD Consortium

Most patients with epithelial ovarian cancer (EOC) are diagnosed at advanced stage and have a poor prognosis. However, a small proportion of these patients will survive, whereas others will die very quickly. Clinicopathological factors do not allow precise identification of these subgroups. Thus, we have validated a molecular subclassification as new prognostic factor in EOC. One hundred and ninety‐four patients with Stage II–IV EOC were characterized by whole‐genome expression profiling of tumor tissues and were classified using a published 112 gene set, derived from an International Federation of Gynecology and Obstetrics (FIGO) stage‐directed supervised classification approach. The 194 tumor samples were classified into two subclasses comprising 95 (Subclass 1) and 99 (Subclass 2) tumors. All nine FIGO II tumors were grouped in Subclass 1 (P = 0.001). Subclass 2 (54% of advanced‐stage tumors) was significantly correlated with peritoneal carcinomatosis and non‐optimal debulking. Patients with Subclass 2 tumors had a worse overall survival for both serous and non‐serous histological subtypes, as revealed by univariate analysis (hazard ratios [HR] of 3.17 and 17.11, respectively; P ≤ 0.001) and in models corrected for relevant clinicopathologic parameters (HR 2.87 and 12.42, respectively; P ≤ 0.023). Significance analysis of microarrays revealed 2082 genes that were differentially expressed in advanced‐grade serous tumors of both subclasses and the focal adhesion pathway as the most deregulated pathway. In the present validation study, we have shown that, in advanced‐stage serous ovarian cancer, two approximately equally large molecular subtypes exist, independent of classical clinocopathological parameters and presenting with highly different whole‐genome expression profiles and a markedly different overall survival. Similar results were obtained in a small cohort of patients with non‐serous tumors. (Cancer Sci 2012; 103: 1334–1341)

Lavage of the Uterine Cavity for Molecular Detection of Müllerian Duct Carcinomas: A Proof-of-Concept Study

Purpose Type II ovarian cancer (OC) and endometrial cancer (EC) are generally diagnosed at an advanced stage, translating into a poor survival rate. There is increasing evidence that Müllerian duct cancers may exfoliate cells. We have established an approach for lavage of the uterine cavity to detect shed cancer cells. Patients and Methods Lavage of the uterine cavity was used to obtain samples from 65 patients, including 30 with OC, five with EC, three with other malignancies, and 27 with benign lesions involving gynecologic organs. These samples, as well as corresponding tumor tissue, were examined for the presence of somatic mutations using massively parallel sequencing (next-generation sequencing) and, in a subset, singleplex analysis. Results The lavage technique could be applied successfully, and sufficient amounts of DNA were obtained in all patients. Mutations, mainly in TP53, were identified in 18 (60%) of 30 lavage samples of patients with OC using next-generation sequencing. Singleplex analysis of mutations previously determined in corresponding tumor tissue led to further identification of six patients. Taken together, in 24 (80%) of 30 patients with OC, specific mutations could be identified. This also included one patient with occult OC. All five analyzed lavage specimens from patients with EC harbored mutations. Eight (29.6%) of 27 patients with benign lesions tested positive for mutations, six (75%) as a result of mutations in the KRAS gene. Conclusion This study proved that tumor cells from ovarian neoplasms are shed and can be collected via lavage of the uterine cavity. Detection of OC and EC and even clinically occult OC was achieved, making it a potential tool of significant promise for early diagnosis.