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Background. African-American women (AAW) have more adverse tumor characteristics than non-African American women (non-AAW) and there is a need for a specific predictive marker for AAW recurrence. Tumors with higher grade and proliferative activity are associated with overexpression of the glucose transporter (Glut-1). An examination of Glut-1 expression relative to recurrence and no recurrence was conducted on both groups to determine if it predicts prognosis and could predict a race specific prognosis. Methods. A breast cancer data set containing clinical information including race and biological characteristics was generated between 1991 and 1996. Tissue samples were selected from this group with similar characteristics in both racial groups for a retrospective analysis of Glut-1 expression using tissue microarrays (TMAs). Mean Glut-1 expression for intensity and percent of tumor cells staining was determined using standard immunohistochemistry. Results. Clinical and biological differences were noted in the original data set between AAW and non-AAW. No significant difference between races was noted in mean Glut-1 values using a subset which had similar characteristics. The mean Glut-1 did not predict recurrence but a rounded score did indicate that higher levels of Glut-1 expression was indicative of a lower disease free survival (p = 0.063). The actual average mean for AAW with no recurrence was significantly lower than any other group (p = 0.04). Conclusions. TMA analysis for Glut-1 expression may be useful to predict disease free survival but it does not predict race specific recurrence.

Herceptin is a humanized antibody that binds to the product of the HER-2 oncogene. Clinical studies have indicated that treatment with Herceptin may slow disease progression in tumors expressing high levels of the HER-2 antigen. However, the mechanism of this action is not known.Four different cell lines were used that had different levels of HER-2 expression. Treated and nontreated cells were analyzed for DNA strand breaks and cell cycle perturbation using standard flow cytometry methods.In this study we found that cell lines expressing high levels of HER-2, when treated with Herceptin, exhibited marked increases in DNA strand breaks as measured by the TUNEL assay, and that these cells also exhibited slowed growth. BT-474 and SKBR-3 cell lines, both of which express high levels of the HER-2 antigen, had significant increases in labeled nucleotide expression at 3 and 6 day time points following exposure to Herceptin at a concentration of 10 microg/ml. Similar treatment of MCF-7 and MDA-231 cell lines, both of which express low levels of HER-2, had little effect on the level of labeled nucleotide expression at either the 3 or 6 day time points. Following 4 days of Herceptin treatment, BT-474 and SKBR-3 cell lines had significant decreases in the percentage of cells in the S phase of growth. This effect was not seen in either the MCF-7 or MDA-231 cell lines.Herceptin has a biological effect only on cells that contain high levels of HER-2. This effect is a decrease in cell proliferation that is coincident with, and may be caused by an increase frequency of DNA strand breaks.

Prognostic factors are highly needed to divide node negative breast cancer patients into groups of low versus high risk of recurrence and death. In order to invade and spread, cancer cells must degrade extracellular matrix proteins. Accordingly, tumor levels of molecules involved in this degradation might be associated with patient outcome. Previous work has demonstrated that high levels of the aspartyl protease cathepsin D in breast cancer are associated with a poor prognosis and similar findings have been reported for molecules involved in the urokinase pathway of plasminogen activation. Interactions between different protease systems have been described and data suggest that several proteolytic enzymes may be operable at the same time in a tumor. In the present study we measured cathepsin D (n=162), uPA (n=116), uPAR (n=109) and PAI-1 (n=135) in tumor cytosols obtained from a population of node negative breast cancer patients. A significant correlation was found between levels of uPA, uPAR, and PAI-1. Levels of cathepsin D were directly related to levels of uPA and uPAR. With a median observation time of 4.81 years, univariate survival analyses showed that high levels of uPA and cathepsin D significantly predicted a shorter disease free survival, while only high levels of cathepsin D were able to significantly predict a shorter overall survival. Tumor levels of uPAR and PAI-1 gave mixed results depending on the cut-off point choosen. Interestingly, multivariate analysis demonstrated that PAI-1 and cathepsin D were independent significant prognostic indicators for disease-free survival while only cathepsin D was helpful in overall survival. The five year relapse rate of patients with low PAI-1 and low cathepsin D was 13% while patients who had greater than the median value for both of these molecules had a 5 year relapse rate of 40%. These data would indicate that at least two different protease systems are active in spread of node negative breast cancer and that measurement of these molecules may aid in the decisions to be made when offering adjuvant treatment to these patients.

The prime importance of axillary node status in predicting recurrence and survival has been appreciated for a long time. More recently routine measurements of estrogen and progesterone receptors have added to our prognostic abilities. The next generation of prognostic markers to be used in the routine clinical setting will be measures of tumor aggressiveness which will prompt therapeutic decisions. The technique of flow cytometry can provide clinicians with two new important pieces of information. First, it gives a measurement of the percentage of cells in S phase of the DNA replicative cycle, in other words, how fast a tumor is growing. Second, it assesses the aneuploidy, or total amount of extra DNA in the tumor cell, which appears to correlate with malignant aggressive tumor behavior.

Flow cytometry (FC), estrogen receptor (ER), and progesterone receptor (PR) analyses were performed on 226 breast cancers. The presence of steroid receptors was inversely proportional to proliferative index and percent aneuploidy. Within the two ER (+ and -) groups, the presence of PR did not add significantly to the comparison. The mean proliferative index for the diploid tumors was 17.5 +/- 6.8 compared to 27.8 +/- 9.8 for aneuploid tumors (p less than .001). The degree of aneuploidy, or DNA index, was not related to cell cycle kinetics or steroid receptor status. In 163 tissues analyzed for percent tumor present, a correlation between the relative number of aneuploid cells and percent tumor in the histologic review was observed. A study of the diploid tumors indicated greater than 75% had at least 10% tumor cells by histologic review. Since with FC one can observe at least 10% aneuploid cells in a tumor sample, it is our opinion that the percent aneuploidy in this study is not artifactually low due to sampling error. There was no significant relationship between nodal status or number of positive nodes and proliferative index, aneuploidy, or steroid receptor status. Metastatic tumors had a higher mean proliferative index, but this was not statistically significant. There was a relationship between age and proliferative index but not between age and ploidy status. In a small group of patients there was a trend for proliferative index and percent aneuploidy to be higher in the poorly differentiated and larger tumors when compared to the well differentiated and smaller tumors.