Image analysis systems for the detection of disseminated breast cancer cells on bone-marrow cytospins

We assessed the accuracy of automated cell imaging systems when compared to manual evaluation of cytospin slides in determining the presence of cytokeratin-positive, disseminated breast cancer cells in bone marrow aspirates. A total of 298 cytospin slides of bone marrow aspirates were first evaluated by individual screening by one expert immunocytologist. Subsequently, all 298 slides were evaluated by the Automated Cell Imaging System (ACIS) by ChromaVisiontrade mark. Two separate analysis cycles were performed using ACIS. The results of the two ACIS analysis cycles were almost identical: in 293 out of 298 samples (98.3%), identical numbers of disseminated breast cancer cells were detected. In the remaining five samples (1.7%), the result of the two ACIS analysis cycles differed by only one tumor cell. By using the manual technique, 120 cytospin samples were found to be positive. ACIS was able to detect additional tumor cells in 64 cases. Not once did ACIS miss tumor cells when compared to the manual technique. Using ACIS, we were able to determine the bone marrow status of patients with nonmetastatic breast cancer faster, with greater accuracy, and with greater reproducibility than with the manual technique.

Breast cancer in young women (?35 years): Genomic aberrations detected by comparative genomic hybridization

Sporadic breast cancer in young women is different from the one in older patients regarding pathological features and aggressiveness of the tumors, but the spectrum of genetic alterations are largely unknown. We used comparative genomic hybridization (CGH) to analyze DNA copy number changes in 88 tumor samples from women </=35 years of age. Findings were compared to histopathological data including tumor type, grading, lymph nodes and metastasis. Genomic gains clustered to chromosome arms 1q (64.8%), 8q (61.4%), 17q (50.0%), 20q (33.0%), 3q (20.5%), 1p (17.0%), 5p (17.0%) and 15q (17%). Losses were commonly located on 8p (19.3 %), 11q (11.4%), 16q (11.4%), 17p (11.4%) and 18q (10.2%). A comparison with published CGH data from breast carcinomas of similar type and grade showed the following differences: (1) gains were much more frequent than losses, and (2) losses on 8p22-p23 were more prevalent in patients with positive lymph node metastasis (p = 0.02), and Grade III tumors were associated with gains on the long arm of chromosome 8 (p = 0.01). Therefore, alterations in these genomic regions may be responsible for the reduced survival of patients with early onset breast cancer.

Exploration of sequence space for protein engineering

The process of protein engineering is currently evolving towards a heuristic understanding of the sequence-function relationship. Improved DNA sequencing capacity, efficient protein function characterization and improved quality of data points in conjunction with well-established statistical tools from other industries are changing the protein engineering field. Algorithms capturing the heuristic sequence-function relationships will have a drastic impact on the field of protein engineering. In this review, several alternative approaches to quantitatively assess sequence space are discussed and the relatively few examples of wet-lab validation of statistical sequence-function characterization/correlation are described.

Clinical relevance of genomic aberrations in homogeneously treated high-risk stage II/III breast cancer patients

Little is known about the prognostic impact of chromosome aberrations in breast cancer. The aim of our study was to determine whether genomic aberrations of prognostic relevance can be identified in the context of a clinical study using molecular cytogenetics. Paraffin-embedded tumor samples of 44 patients with high-risk stage II/III breast cancer were analyzed by comparative genomic hybridization. All patients received identical therapy including dose-escalated chemotherapy followed by peripheral blood stem cell transplantation. The most frequent chromosomal aberrations were gains on chromosome arms 17q (24 cases), 1q (21 cases), 8q (17 cases), 20q (13 cases), 6p (9 cases) as well as losses on chromosome arms 13q (25 cases), 11q (20 cases), 5q (11 cases), 6q (11 cases), 9p (10 cases), 18q (10 cases), 8p (9 cases) and 16q (9 cases). In univariate analysis, the correlation with the clinical outcome revealed a higher risk for patients with tumors exhibiting 13q losses and a reduced risk for tumors exhibiting 16q losses (p = 0.020), 6q losses (p = 0.041) and estrogen-receptor positivity (0.051). In multivariate analysis using the Cox model, only the loss of 16q exhibited borderline significance (p = 0.065). These data show that comparative genomic hybridization can be performed in the context of a clinical trial. In our subgroup of high-risk breast cancer patients, chromosomal aberrations were valuable prognostic parameters.

Aberrant cytoplasmic expression of the p16 protein in breast cancer is associated with accelerated tumour proliferation

The p16 protein plays an important role in the transition of cells into the G1 phase of the cell cycle. We have studied the prevalence of p16 protein expression in breast carcinomas in a prospective series of 368 invasive and 52 non-invasive malignancies, as well as in 88 locally recurring tumours and three tumour cell lines. p16 protein expression was evaluated immunohistochemically on paraffin sections using monoclonal and polyclonal anti-p16 antibodies, and by immunoblotting of tumour cell suspensions. Tumour cell lines were also subjected to polymerase chain reaction-single strand polymorphism (PCR-SSCP) analysis and direct DNA sequencing. The results were compared with established prognostic parameters, DNA flow cytometry and p53 protein expression. In 33 (9%) invasive and two (4%) intraductal carcinomas, a cytoplasmic accumulation of the p16 protein was seen. These cases were characterized by poor histological grade of differentiation, loss of of oestrogen receptors and progesterone receptors and frequent overexpression of the p53 protein. In addition, breast carcinomas with aberrant p16 expression demonstrated a high proliferative activity, with median S-phase fractions 74% higher than in the control group and the median Ki67 fractions elevated to 75%. A genetic alteration of the p16 gene was not detectable in three analysed cell lines with cytoplasmic p16 expression applying PCR-SSCP and direct DNA sequencing. These results indicate that cytoplasmic accumulation of the p16 protein identifies a subset of highly malignant breast carcinomas with accelerated tumour proliferation and other unfavourable parameters in breast cancer. The described protein accumulation is apparently not caused by an alteration of the p16 gene.

[Complete remission after salvage chemotherapy in metastatic breast carcinoma after failure of induction cycles of planned high dosage chemotherapy with stem cell support]

We report on a patient with metastatic breast cancer confined to visceral (lung and pleura) site. A high-dose chemotherapy with peripheral progenitor blood cell transplantation was indicated. In contrast to other 24 patients two induction cycle chemotherapies (intensive dosis of Epirubicin/Ifosfamid/GCSF) didn't show any remission of metastases. Therefore a high dose chemotherapy with peripheral progenitor blood cell transplantation was not indicated any more. This patient had lung and pleura metastases and showed a complete remission after the following conventional chemotherapy (Carboplatin/Toxol) persisting more than 7 months. Non-responder after induction therapies have a poor prognosis but salvage therapy may be successful anyway. Mammary neoplasms can be sensible on special chemotherapy drugs only.