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Gert Auer

Publications and source records attributed to Gert Auer.

At least 37 records · Page 2Linked to original sources

Prognostic factors in surgical stage I endometrial carcinoma.

The prognostic impact of DNA ploidy, MIB-1 and p53 was evaluated in relation to clinical and histopathological features in surgical stage I endometrial carcinoma (n = 284) and in the histopathological endometrioid subgroup (n = 257). Tumour material from 284 consecutive patients was analysed regarding image cytometric DNA ploidy and the immunohistochemical MIB-1 and p53 expression. Twenty-four tumours relapsed. In univariate analysis, histopathological subgroup (endometrioid vs. non-endometrioid), grade, DNA ploidy and p53 were highly significant prognostic factors (p < or = 0.001). MIB-1 was also significant (p = 0.039). In the endometrioid subgroup only DNA ploidy and p53 were significant (p < 0.001). In multivariate analysis of the entire material, ploidy and histopathological subgroup retained their significance (p = 0.001, p = 0.004), whereas only ploidy was significant in the endometrioid subgroup (p = 0.001). DNA ploidy was the strongest predictor of relapse-free survival and the only independent prognostic factor in the endometrioid subgroup.

Adult↗

Image cytometry DNA-analysis of fine needle aspiration cytology to aid cytomorphology in the distinction of branchial cleft cyst from cystic metastasis of squamous cell carcinoma: a prospective study.

OBJECTIVE: Frequently, the distinction between branchial cleft cyst and cystic metastases from squamous cell carcinoma is difficult by cytomorphology. In a prospective study, we investigated the need for, and the value of, image cytometry DNA-analysis as a complement to cytologic evaluation of cystic lesions in the neck. STUDY DESIGN: Image cytometry DNA-analysis was performed on the fine needle aspiration cytology smears from 50 patients, referred to our department, with a solitary cystic lesion in the lateral region of the neck. METHODS: Smears from aspirates were Giemsa stained and cytologically evaluated. Ahrens image analysis was used for DNA analysis on smears stained with Schiff reagent, and lymphocytes were used as control cells. Epithelial cells with DNA values exceeding 5c were regarded as aneuploid, indicating malignancy. RESULTS: Nine lesions were diagnosed as squamous cell cancer metastases cytologically. DNA analysis showed aneuploidy in all of them except one. Three of these lesions had earlier been diagnosed as branchial cleft cyst at the referring hospital. Eight lesions were cytologically inconclusive and four of them were revealed as cystic metastasis at histopathologic analysis, and DNA analysis showed aneuploidy in all but one, which could not be analyzed. Two of these lesions were also diagnosed as branchial cleft cysts at the referring hospital. All benign lesions were diploid. Nine lesions were thyroid and salivary gland lesions. CONCLUSION: Image cytometry DNA-analysis was shown to help in the distinction between benign and malignant cystic lesions. Thus, when conventional cytomorphology does not suffice, DNA-analysis is clearly a valuable supplement.

Adolescent↗

Laminin-5 gamma2 chain expression facilitates detection of invasive squamous cell carcinoma of the uterine cervix.

Because it has been suggested that laminin-5 can be used as a sensitive marker for epithelial cell invasion, specimens from patients with invasive squamous cell carcinoma of the uterine cervix with a previous history of preinvasive lesions were evaluated by a newly developed monoclonal antibody directed against the gamma2 chain of laminin-5. Thirty-two archival paraffin specimens consisting of the matched preinvasive and invasive lesions from 15 women were evaluated to determine whether gamma2 chain laminin-5 staining was present in lesions that progressed to invasive cancer. With the exception of one tumor (a small cell nonkeratinizing squamous carcinoma), all squamous cell carcinomas exhibited positive staining. Five of 17 preinvasive lesions also were immunoreactive for the laminin-5 protein. A blinded histologic reevaluation revealed invasion or lesions suspicious for invasion in four of five preinvasive lesions. Our findings suggest that laminin-5 determined by a monoclonal antibody facilitates the identification of invasive lesions that are difficult or impossible to identify on routinely stained histologic sections.

Antibodies, Monoclonal↗

Comparative genomic hybridization analysis of tonsillar cancer reveals a different pattern of genomic imbalances in human papillomavirus-positive and -negative tumors.

Our aim was to map and compare genomic imbalances in human papillomavirus (HPV)-positive and -negative squamous cell carcinomas of the tonsil. Twenty-five primary carcinomas were analyzed by comparative genomic hybridization. Fifteen (60%) were found to be HPV-positive by PCR, and the majority were HPV-16. There were statistically significant differences in the distribution of DNA gains and losses between the HPV-positive and -negative samples. Eleven of 15 HPV-positive samples (73%) showed gain on chromosome 3q24-qter, while only 4/10 (40%) HPV-negative samples had the same gain (p = 0.049). Furthermore, 4/10 (40%) HPV-negative samples but no HPV-positive samples had gain on chromosome 7q11.2-q22 (p = 0.017). As expected, and similar to previous studies, patients with an HPV-positive tumor had a statistically significantly better disease-specific survival than patients with an HPV-negative tumor (p = 0.002). The most common changes, e.g., gain on 3q or 8q, loss on 11q or 13 and loss on chromosome 7q in HPV-negative tumors, did not have any influence on prognosis. However the number of cases in each subgroup was limited.

Adult↗

Expression of cyclins A, E and topoisomerase II alpha correlates with centrosome amplification and genomic instability and influences the reliability of cytometric S-phase determination.

BACKGROUND: The progression of normal cells through the cell cycle is meticulously regulated by checkpoints guaranteeing the exact replication of the genome during S-phase and its equal division at mitosis. A prerequisite for this achievement is synchronized DNA-replication and centrosome duplication. In this context the expression of cyclins A and E has been shown to play a principal role. RESULTS: Our results demonstrated a correlation between centrosome amplification, cell cycle fidelity and the level of mRNA and protein expression of cyclins A and E during the part of the cell cycle defined as G1-phase by means of DNA content based histogram analysis. It is shown that the normal diploid breast cell line HTB-125, the genomically relatively stable aneuploid breast cancer cell line MCF-7, and the genomically unstable aneuploid breast cancer cell line MDA-231 differ remarkably concerning both mRNA and protein expression of the two cyclins during G1-phase. In MDA-231 cells the expression of e.g. cyclin A mRNA was found to be ten times higher than in MCF-7 cells and about 500 times higher than in HTB-125 cells. Topoisomerase II alpha showed high mRNA expression in MDA compared to MCF-7 cells, but the difference in protein expression was small. Furthermore, we measured centrosome aberrations in 8.4% of the MDA-231 cells, and in only 1.3% of the more stable aneuploid cell line MCF-7. MDA cells showed 27% more incorporation of BrdU than reflected by S-phase determination with flow cytometric DNA content analysis, whereas these values were found to be of the same size in both HTB-125 and MCF-7 cells. CONCLUSIONS: Our data indicate that the breast cancer cell lines MCF-7 and MDA-231, although both DNA-aneuploid, differ significantly regarding the degree of cell cycle disturbance and centrosome aberrations, which partly could explain the different genomic stability of the two cell lines. The results also question the reliability of cytometric DNA content based S-phase determination in genomically unstable tumor cell populations.

Antigens, Neoplasm↗

Detection of genomic amplification of the human telomerase gene (TERC) in cytologic specimens as a genetic test for the diagnosis of cervical dysplasia.

Invasive cervical carcinomas frequently reveal additional copies of the long arm of chromosome 3. The detection of this genetic aberration in diagnostic samples could therefore complement the morphological interpretation. We have developed a triple-color DNA probe set for the visualization of chromosomal copy number changes directly in thin-layer cervical cytology slides by fluorescence in situ hybridization. The probe set consists of a BAC contig that contains sequences for the RNA component of the human telomerase gene (TERC) on chromosome band 3q26, and repeat sequences specific for the centromeres of chromosomes 3 and 7 as controls. In a blinded study, we analyzed 57 thin-layer slides that had been rigorously screened and classified as normal (n = 13), atypical squamous cells (ASC, n = 5), low-grade squamous intraepithelial lesions (LSIL, n = 14), and high-grade squamous intraepithelial lesions (HSIL) grade 2 (CIN2, n = 8), and grade 3 (CIN3, n = 17). The percentage of tetraploid cells (P(Trend) < 0.0005) and cells with multiple 3q signals increased with the severity of the cytologic interpretation (P(Trend) < 0.0005). While only few normal samples, ASC and LSIL lesions, revealed copy number increases of 3q, 63% of the HSIL (CIN2) lesions and 76% of the HSIL (CIN3) lesions showed extra copies of 3q. We conclude that the visualization of chromosome 3q copy numbers in routinely prepared cytological material using BAC clones specific for TERC serves as an independent screening test for HSIL and may help to determine the progressive potential of individual lesions.

Algorithms↗

Pronounced chromosomal instability and multiple gene amplifications characterize ulcerative colitis-associated colorectal carcinomas.

Patients with ulcerative colitis have a significantly increased lifetime risk for the development of colorectal carcinomas. While genetic and genomic changes during carcinogenesis have been thoroughly studied in sporadic colorectal cancers, less is known about ulcerative colitis-associated colorectal carcinomas. The aim of this study was to extend the identification of specific genomic imbalances to ulcerative colitis-associated colorectal carcinomas and to establish a comprehensive map of DNA gains and losses by investigating 23 tumor specimens from 23 patients. The molecular cytogenetic characterization was performed using comparative genomic hybridization; immunohistochemistry was used to measure proliferative activity and laminin-5 expression as a marker for invasiveness. The results indicate that these tumors are invariably aneuploid, with a high proliferative activity and increased invasive potential. The average number of copy alterations correlates with increased cyclin A levels (P=0.044), which is an independent predictor of risk of carcinoma development in ulcerative colitis. Despite severe genetic instability, the general pattern of specific chromosomal aberrations that defines sporadic colorectal carcinomas is maintained in ulcerative colitis-associated malignancies. High-level copy number increases (amplifications) are dispersed throughout the genome. Strikingly, these amplifications are much more frequent than in sporadic carcinomas and map to chromosomal regions that have not been described before.

Adenocarcinoma↗

Usefulness of TA02 (napsin A) to distinguish primary lung adenocarcinoma from metastatic lung adenocarcinoma.

TA02 (napsin A) associated with primary lung adenocarcinoma detected by the two-dimensional polyacrylamide gel electrophoresis (2-DE), has a molecular weight of 35.0 kDa and an isoelectric point 5.29. We developed a mouse monoclonal antibody against the N-terminal of the TA02 molecule (clone TMU-Ad02 (6A1)) and attempted to investigate its immunohistochemical reactivity for nodular lesions of the peripheral lung, and evaluate its usefulness for making a differential diagnosis between primary and metastatic lung adenocarcinomas. The TA02-immunohistochemical evaluation was carried out using surgically resected materials of 109 cases of lung cancer (76 cases of primary lung cancer and 33 cases of metastatic lung adenocarcinoma from other organs), five cases with mesothelioma, four cases with atypical adenomatous hyperplasia (AAH) and five cases with tuberculoma of the lung. In 39 out of 43 (90.7%) primary lung adenocarcinomas, positive immunohistochemical reactivity with a granular cytoplasmic staining pattern was observed. Even though two out of seven (28.6%) large cell carcinomas showed positive results with a granular staining pattern, the immunohistochemical staining intensity was weak. The other cancerous lesions containing metastatic lung adenocarcinoma and mesothelioma were all completely negative. In comparison with the immunohistochemical reactivity of TA02 and SpA, TA02 was superior to SpA both in terms of positive rate and immunohistochemical intensity. We concluded that the evaluation of TA02 expression in lung tumorous lesions was very valuable for discriminating between primary and metastatic lung adenocarcinoma, and TA02 was superior to SpA as a discriminating marker.

Adenocarcinoma↗

MIB-1 index in thyroid tumors: a predictor of the clinical course in papillary thyroid carcinoma.

MIB-1 is useful in evaluating proliferative activity and in predicting the aggressiveness in a variety of tumors. To investigate if MIB-1 immunoreactivity can add prognostic information to conventional prognostic variables in papillary thyroid carcinoma (PTC), 30 PTCs were evaluated using the MIB-1 antibody. For comparison, 10 follicular thyroid carcinomas (FTC), 8 anaplastic thyroid carcinomas (ATC), and 96 follicular thyroid adenomas (FTA) were similarly analyzed. The median MIB-1 index was 0.5% in FTA, 1.9% in PTC, 2.7% in FTC, and 16.2% in ATC. The 13 tumors from patients classified as having aggressive PTC (defined as dead from disease, persisting disease, or the occurrence of distant metastases) had significantly higher MIB-1 index (median, 5.4%) than the 17 patients with nonaggressive disease (median, 1.1%). MIB-1 index 1.85% or more was found to be an independently significant risk factor for a less favorable clinical course in PTC. Because of overlap of single values the utility of MIB-1 index as a clinical test is somewhat limited. Still, at levels where no overlap occurs (MIB-1 index 2 3.2% or ' 0.5%) the index seems to add information to the established prognostic parameters. MIB-1 index should therefore be considered in routine histopathology of PTC.

Adenocarcinoma, Follicular↗

DNA amplifications and aneuploidy, high proliferative activity and impaired cell cycle control characterize breast carcinomas with poor prognosis.

In order to explore whether specific cytogenetic abnormalities can be used to stratify tumors with a distinctly different clinical course, we performed comparative genomic hybridization (CGH) of tumors from patients who were diagnosed with metastatic disease after an interval of less than 2 years or who remained free from distant metastases for more than 10 years. All patients presented with distant metastases after mastectomy indicating that none of the patients in this study was cured and free of remaining tumor cells. Tumors in the group of short-term survivors showed a higher average number of chromosomal copy alterations compared to the long-term survivors. Of note, the number of sub-chromosomal high-level copy number increases (amplifications) was significantly increased in the group of short-term survivors. In both short- and long-term survivors recurrent chromosomal gains were mapped to chromosomes 1q, 4q, 8q, and 5p. Copy number changes that were more frequent in the group of short-term survivors included gains of chromosome 3q, 9p, 11p and 11q and loss of 17p. Our results indicate that low- and high grade malignant breast adenocarcinomas are characterized by a specific pattern of chromosomal copy number changes. Furthermore, immunohistochemical evaluation of the expression levels of Ki-67, p27KIP1, p21WAF1, p53, cyclin A and cyclin E revealed a correlation between increased proliferative activity and poor outcome.

Adenocarcinoma↗

Inhibition of Rel/Nuclear Factor-kappaB signaling in skin results in defective DNA damage-induced cell cycle arrest and Ha-ras- and p53-independent tumor development.

In recent years a growth inhibitory role in skin for the Rel/NF-kappaB transcription factors has been established, and the block of Rel/NF-kappaB signaling results in rapid development of spontaneous skin cancer. The molecular mechanism underlying tumor development is however unknown. In the present study, we show that inhibition of NF-kappaB signaling in mouse skin by targeted expression of degradation resistant IkappaB-alpha generates transgenic keratinocytes unable to arrest the cell cycle in response to DNA damage induced by gamma-radiation. The results indicate that transgenic keratinocytes have a defect at the G1-S checkpoint whereas the G2-M checkpoint response was found to be intact. However, transgenic keratinocytes still respond by induction of the cyclin dependent kinase inhibitor p21(Cip1/Waf) after exposure to gamma-radiation. In the spontaneous skin tumors that develop in transgenic mice no mutations were found in the Ha-ras or p53 gene, suggesting that inhibition of NF-kappaB signaling in skin can induce cancer development independently of initiating mutations in the Ha-ras gene or additional mutations in the p53 gene. These findings demonstrate an involvement of NF-kappaB signaling in the DNA damage response and cell cycle checkpoint control in the skin.

Animals↗

Molecular classification of borderline ovarian tumors using hierarchical cluster analysis of protein expression profiles.

Ovarian tumors range from benign to aggressive malignant tumors, including an intermediate class referred to as borderline carcinoma. The prognosis of the disease is strongly dependent on tumor classification, where patients with borderline tumors have much better prognosis than patients with carcinomas. We here describe the use of hierarchical clustering analysis of quantitative protein expression data for classification of this type of tumor. An accurate classification was not achieved using an unselected set of 1,584 protein spots for clustering analysis. Different approaches were used to select spots that were differentially expressed between tumors of different malignant potential and to use these sets of spots for classification. When sets of proteins were selected that differentiated benign and malignant tumors, borderline tumors clustered in the benign group. This is consistent with the biologic properties of these tumors. Our results indicate that hierarchical clustering analysis is a useful approach for analysis of protein profiles and show that this approach can be used for differential diagnosis of ovarian carcinomas and borderline tumors.

Adult↗

Detection of chromosomal aneuploidies and gene copy number changes in fine needle aspirates is a specific, sensitive, and objective genetic test for the diagnosis of breast cancer.

Fine needle aspiration cytology is central to the evaluation of clinically or mammographically detected suspicious lesions of the breast. On the basis of results from studies of >500 breast cancers by comparative genomic hybridization we have developed protocols and designed probe sets that allow one to visualize recurrent chromosomal aneuploidies, amplification of oncogenes, and deletion of tumor suppressor genes directly in cytological preparations using multicolor fluorescence in situ hybridization. The fluorescence in situ hybridization probes are specific for chromosome arm 1q, the c-MYC and HER2 oncogenes, the tumor suppressor gene p53 and, as controls for chromosome ploidy of each cell, the centromeres of chromosomes 8, 10, and 17. Application of these diagnostic mixtures to 20 invasive breast cancers, 7 mastopathias, and 2 fibroadenomas demonstrates that a highly sensitive, specific, and objective diagnosis of breast cancer is now possible on cytological preparations obtained by minimally invasive fine needle aspiration.

Aneuploidy↗

The clinical value of image cytometry DNA analysis in distinguishing branchial cleft cysts from cystic metastases of head and neck cancer.

OBJECTIVES/HYPOTHESIS: A branchial cleft cyst presents as a lump in the neck that, generally, is easily cured by surgical excision. The preoperative diagnosis is based on clinical examination and, especially in the Scandinavian countries, fine-needle aspiration cytology. However, at times, the histopathological analysis of the excised cyst reveals a cystic metastasis of squamous cell carcinoma of the head and neck. If adequate diagnosis could be obtained preoperatively, patients would most likely fare better. The study was performed to investigate whether the diagnostic accuracy for these lesions could be improved preoperatively by image cytometry DNA analysis of the fine-needle aspiration cytology specimen. STUDY DESIGN: Image cytometry DNA analysis was performed on the preoperative fine-needle aspiration cytology specimen and the surgical specimens from 51 patients with solitary cysts in the lateral region of the neck. Thirty-six patients were selected because there was a discrepancy between findings on fine-needle aspiration cytology and the final histopathological diagnosis or an uncertain cytological diagnosis. There were 25 metastatic squamous cell carcinomas and 3 thyroid cancers, there was 1 lymphoma and 1 sialoadenitis, and there were 21 branchial cleft cysts. METHODS: The cytodiagnostic Giemsa-stained slides were destained in Methanol and then stained with Schiff's reagent. The paraffin-embedded material from excised cysts were cut and deparaffinized and then stained with Schiff's reagent. Ahrens image analysis was used for DNA analysis and lymphocytes were used as control cells. DNA valves exceeding 5c was regarded as aneuploid. RESULTS: Image cytometry DNA analysis of the preoperative cytological specimen was possible in 41 of 51 patients. We found that in 53% of the cases with cystic metastasis, image cytometry DNA analysis, when possible, revealed aneuploidy, thus indicating malignancy. DNA analysis showed diploidy in all benign cases. CONCLUSIONS: Aneuploidy is highly specific for malignancy. Image cytometry DNA analysis increases the diagnostic sensitivity for malignant cystic metastasis and therefore is a valuable supplement to conventional cytological study for these lesions.

Adult↗

Chromosomal imbalances are associated with metastasis-free survival in breast cancer patients.

Multiple chromosomal imbalances have been identified in breast cancer using comparative genomic hybridization (CGH). Their association with the primary tumors' potential for building distant metastases is unknown. In this study we have investigated 39 invasive breast carcinomas with a mean follow-up period of 99 months (max. 193 months) by CGH to determine the prognostic value of chromosomal gains and losses. The mean number of chromosomal imbalances per tumor was 6.5+/-0.7 (range 2 to 18). The most frequent alterations identified in more than 1/3 of cases were gains on chromosomes 11q13, 12q24, 16, 17, and 20q, and losses on 2q and 13q. A significantly different frequency of chromosomal aberrations (p<or=0.05) was found between DNA-diploid and non-diploid tumors (gain on chromosome 17). Differences were also noted between tumors progressing to distant metastases within the period of follow-up and those which do not (gains on 11q13 and 12q24; loss on 12q). Significant univariate correlations (p<or=0.05) with the metastasis-free survival of patients were found for lymph node status, the cytometrical determined DNA ploidy (diploid/non-diploid) and anisokaryosis, and for DNA gains on 11q13, 12q24, 17, and 18p. An unexpected inverse correlation was found between clinical outcome and gains on 11q13 and 12q24. In multivariate analysis independent prognostic value, in addition to lymph node status, was found for chromosomal gains on 11q13, 12q24, 17 and 18p. Amplification on 20q, which did not correlate with metastasis-free survival in a univariate analysis, showed weak prognostic significance in combination with the nodal status. The prognostic value of chromosomal alterations - some of them by inverse correlation - suggests an interaction and/or compensation of the involved amplified genes and their effects on the occurrence of distant metastases in breast cancer patients.

Breast Neoplasms↗

Aberrations of centrosomes in adrenocortical tumors.

The frequent and generalized chromosomal imbalances that are characteristic of adrenocortical carcinomas suggest that incomplete chromosome segregation often takes place in these tumors. As a step towards elucidating the mechanism behind the multiple numerical chromosomal aberrations, we have evaluated a series of 14 such tumors for centrosome abnormalities using immunohistochemical detection of the gamma-tubulin centrosome component. The proportion of cells with more than the expected number of 2 centrosomes was moderately increased in the 4 adenomas (1-7%), while a high increase was observed in the 10 carcinomas (1-19%), as compared to the normal reference tissues (0.3%) (p<0.001). Similarly, the centrosome amplification tended to be more pronounced in the carcinomas where the aberrant cells carried 3 or 4 positive signals in 9 of the 10 tumors, and 6 signals were recorded in one tumor, while in the adenomas more than 3 signals was only recorded in one of the 4 cases. The findings demonstrate that centrosome amplifications occur frequently in both adrenocortical adenomas and carcinomas, thus supporting its role in driving the tumor development as opposed to being a consequence of it. Furthermore, the more pronounced occurrence in the malignant form as well as in the larger tumors, offers one likely explanation for the increasing generalized aneuploidy observed during the tumor development, and points to new therapeutic strategies aimed at restoring normal centrosome function.

Adenoma↗

Human papillomavirus and DNA ploidy in tonsillar cancer--correlation to prognosis.

BACKGROUND: Human papillomavirus (HPV) is frequently observed in tonsillar cancer. Here, tonsillar tumors were examined to see whether DNA content varied depending on HPV status, and influenced clinical outcome. MATERIALS AND METHODS: Image cytometry (ICM) was used for DNA content analysis and PCR for HPV analysis in 66 tonsillar cancer biopsies. RESULTS: Most tumors exhibited a high degree of aneuploidy, while only 12% were diploid. Although non-significant, proportionally more patients with cancer with a 5c ER below the mean value compared to patients with tumors with a 5c ER above the mean value were disease-free and displayed a better survival. Forty-five percent of the tumors were HPV-16-positive. Significantly more HPV-positive tumors than HPV-negative tumors had a 5c ER below the mean value and more patients with HPV- positive, compared to patients with HPV-negative tumors stayed disease-free and had a better survival. CONCLUSION: Tonsillar cancer displays a high degree of aneuploidy, albeit HPV-positive tumors have a lower degree of aneuploidy than HPV-negative tumors. Finally, HPV status provides a stronger prognostic value in tonsillar cancer than DNA content.

Adult↗