Cell kinetics in human breast cancer: comparison between the prognostic value of the cytofluorimetric S-phase fraction and that of the antibodies to Ki-67 and PCNA antigens detected by immunocytochemistry

The Role of Transforming Growth Factor Beta and Smad Receptors in Determining Prognosis in High-Grade Primary Brain Tumors: Glioblastoma Multiforme

Introduction High-grade primary brain tumors cause serious morbidity and mortality. This study aimed to investigate the role of transforming growth factor beta (TGF-β) and suppressor of mothers against decapentaplegic (Smad) receptors in high-grade primary brain tumors.

Material and Method Thirteen patients with a pathological diagnosis of glioblastoma multiforme were included in the study. Pathological preparations of each patient were analyzed retrospectively in histochemistry and immunohistochemistry laboratories. Transforming growth factor beta 1, TGF-β2, TGF-β3, Smad 1/2/3, Smad 6, and Smad 7 stainings were evaluated, and the immunoreactivity densities were examined.

Result We found out an increase in the expression of TGF-β1 and TGF-β3 protein. Regarding the inhibitin receptors, Smad 6 showed much more expression than Smad 7. Thus, we found that Smad 6 has a protective effect and role in the tissue. Immunhistochemically, TGF-β family stains, which are activated by types I-and -II receptors, and the stainless staining of the Smad family might also be showing that the TGF-β family is taking action with a secondary pathway other than the Smad family.

Conclusion In addition to Smad family receptors, Shc-GBR2, SARA, and Ras-Erk1/2 receptors should be investigated in future research. After that, the prognosis, diagnosis, and patient-based chemotherapy strategies for the treatment of glioblastoma multiforme may take a more prominent role.

The STAT3 inhibitor pyrimethamine displays anti-cancer and immune stimulatory effects in murine models of breast cancer

The transcription factor signal activator and transducer or transcription (STAT3), which regulates genes controlling proliferation, survival, and invasion, is activated inappropriately in many human cancers, including breast cancer. Activation of STAT3 can lead to both malignant cellular behavior and suppression of immune cell function in the tumor microenvironment. Through a chemical-biology screen, pyrimethamine (PYR), an FDA approved anti-microbial drug, was identified as an inhibitor of STAT3 function at concentrations known to be achieved safely in humans. We report that PYR shows therapeutic activity in two independent mouse models of breast cancer, with both direct tumor inhibitory and immune stimulatory effects. PYR-inhibited STAT3 activity in TUBO and TM40D-MB metastatic breast cancer cells in vitro and inhibited tumor cell proliferation and invasion into Matrigel basement membrane matrix. In tumor-transplanted mice, PYR had both direct and indirect tumor inhibitory effects. Tumor-bearing mice treated with PYR showed reduced STAT3 activation in tumor cells, attenuated tumor growth, and reduced tumor-associated inflammation. In addition, expression of Lamp1 by tumor infiltrating CD8+ T cells was elevated, indicating enhanced release of cytotoxic granules. These findings suggest that PYR may have beneficial effects in the treatment of breast cancer.

Low concordance of biomarkers in histopathological and cytological material from breast cancer

AIMS

The aim of this study was to investigate in primary breast cancer the congruency of routine clinical predictive biomarker evaluations, including ER, PR and Ki67, obtained using immunocytochemistry (ICC) and immunohistochemistry (IHC).

METHODS AND RESULTS

Clinicopathological data were collected on all women diagnosed with primary breast cancer at Karolinska University Hospital in 2011. A total of 346 patients were included in a retrospective paired comparison of predictive biomarker evaluations on direct smear ICC and IHC. This showed a low congruency between findings with the two methods, especially evident for Ki67 (κ = 0.35-0.42). By suggested adjustments to ICC cut-offs, we managed to improve the inter-rater agreement of Ki67 classification slightly to κ = 0.46.

CONCLUSIONS

Our findings suggest that routine clinical ICC and IHC evaluations of predictive biomarkers produce discordant results. Consequently, basing therapeutic decisions on cytology with cut-offs defined for IHC induces a risk that patients will receive suboptimal therapy. However, our analysis shows that local adjustments to biomarker cut-off levels may improve congruency and increase the probability of correct classifications.

Ki-67 biomarker in breast cancer of Indian women

Background:

Biological markers that reliably predict clinical or pathological response to primary systemic therapy early during a course of chemotherapy may have considerable clinical potential.

Aims:

Aims of study to evaluated changes in Ki-67 (MIB-1) labeling index and apoptotic index (AI) before, during, and after neoadjuvant anthracycline chemotherapy in breast cancer in Indian women.

Materials and Methods:

Breast cancer tissues were collected from Grant Medical College and Sir J.J. Group of Hospitals, Mumbai, India. Twenty-seven patients receiving neoadjuvant FEC (5-fluorouracil, epirubicin, and cyclophosphamide) chemotherapy for operable breast cancer underwent repeat core biopsy after 21 days of treatment.

Results:

The objective clinical response rate was 56%. Eight patients (31%) achieved a pathological response by histopathological criteria; two patients had a near-complete pathological response. Increased day-21 AI was a statistically significant predictor of pathological response (p = 0.049). A strong trend for predicting pathological response was seen with higher Ki-67 indices at day 21 and AI at surgery (p = 0.06 and 0.06, respectively).

Conclusion:

The clinical utility of early changes in biological marker expression during chemotherapy remains unclear. Until further prospectively validated evidence confirming the reliability of predictive biomarkers is available, clinical decision-making should not be based upon individual biological tumor biomarker profiles.

Prognostic value of proliferation markers: immunohistochemical ki-67 expression and cytometric s-phase fraction of women with breast cancer in libya

Background: We evaluated the association of the immunohistochemical Ki-67 expression, and S-phase fraction with clinicopathological variables and patient outcome.

Patients and methods: Histological samples from 100 primary Libyan breast carcinoma patients were retrospectively studied with monoclonal antibody to Ki-67. S-phase fraction was determined by DNA image cytometry.

Results: The median Ki-67 percentage for all tumors was 27.5%, ranging from 1 to 80% and the median S-phase fraction (SPF) was 11%, ranging from 0 to 62 %. Tumors with high Ki-67 expression were found in 76% of patients and with high SPF values in 56%. Ki-67 expression was more frequent in tumors with high SPF than low SPF. High Ki-67 and high SPF were associated with advanced stages, poor differentiation of tumors, positive lymph nodes, and distant metastasis. The Ki-67 was associated with hormone receptor negative tumors. The SPF was higher in young patients (<50 years) than in older patients. In the overall population (median follow-up 49 months), patients with high Ki-67 and high SPF had shorter survival time and predicted recurrence than patients with low Ki-67 and low SPF. In a Cox multivariate analysis, high SPF (p= 0.007), hormonal status (p= 0.001) and clinical stage (p=0.005) were independent predictors of disease-specific survival. The Ki-67 (p=0.065) in borderline significance proved to be independent predictor of disease-free survival. The SPF showed more statistically significance with a high grade of malignancy and survival time than Ki-67.

Conclusions: The SPF value is useful cell proliferation marker to assess tumor prognosis. These markers may reflect the aggressive behavior of Libyan breast cancer and predict of the recurrence. It is therefore important to take these markers into consideration to select a high risk subgroup of the patients for intensive treatment.

Exploring the anti-tumour activity of bisphosphonates in early breast cancer

Bisphosphonates are potent inhibitors of osteoclast-mediated bone resorption and are firmly established in the management of breast cancer patients with metastatic skeletal disease. There are extensive data that bisphosphonates, particularly nitrogen-containing bisphosphonates such as zoledronic acid, exhibit anti-tumour activity potentially via both indirect and direct mechanisms in vitro. In vivo studies using animal models of breast cancer induced bone disease have shown that bisphosphonates exert anti-tumour effects via inhibiting osteolysis and reducing skeletal tumour burden. Furthermore, pre-clinical studies have demonstrated synergistic anti-tumour effects between chemotherapy agents commonly used in breast cancer treatment and nitrogen-containing bisphosphonates. This, coupled with emerging evidence from pre-clinical in vivo studies suggesting that bisphosphonates may have additional anti-tumour activity outside of the bone microenvironment, could be of significant importance in the clinical management of breast cancer. The evidence in favour of an anti-tumour effect of bisphosphonates in the clinical setting is inconclusive however, with conflicting evidence from several trials. This review focuses on the anti-tumour activity of bisphosphonates in breast cancer, with particular focus on zoledronic acid. The pre-clinical evidence for anti-tumour activity will be reviewed, followed by the synergistic effects with anti-cancer agents. Finally, the clinical relevance and strategies for the evaluation of anti-tumour activity in breast cancer will be discussed. We are currently exploring the potential synergistic anti-tumour effects of the sequential treatment of neoadjuvant chemotherapy followed by zoledronic acid in a randomised phase II study evaluating biological endpoints including apoptosis, proliferation and angiogenesis in patients with breast cancer.

Use of the Oncotype DX 21-gene assay to guide adjuvant decision making in early-stage breast cancer

The decision to use adjuvant chemotherapy in patients with early stage breast cancer involves the consideration of many factors that traditionally rely heavily on tumor size and lymph node involvement and a limited set of biologic characteristics such as estrogen receptor and HER2 expression. Overtreatment with cytotoxic chemotherapy is a significant concern among patients and physicians. Using the currently accepted guidelines it has been estimated that a large percentage of patients receiving chemotherapy for low-risk breast cancers may be overtreated. Gene expression profiling is a new technology being developed to help improve risk stratification of patients and to predict outcomes. The Oncotype DXtrade mark assay is one example of a gene expression profile validated in women with lymph node-negative, estrogen receptor-expressing breast cancer. This assay and others aim to help improve risk classification and recurrence prediction and, therefore, optimize selection of patients for adjuvant chemotherapy.

Measurement of pancreatic islet cell proliferation by heavy water labeling

We describe a sensitive technique for measuring long-term islet cell proliferation rates in vivo in rats. Pancreatic islets were isolated and the incorporation of deuterium ((2)H) from heavy water ((2)H(2)O) into the deoxyribose moiety of DNA was measured by GC-MS. The results of heavy water labeling and BrdU staining were compared. The two methods were highly correlated (r = 0.9581, P < 0.001). Based on long-term heavy water labeling, approximately 50% of islet cells divided in rats between 8 and 15 wk of age. Of interest, long-term BrdU administration suppressed proliferation of islet cells significantly, but not of bone marrow cells. Physiological evidence further supported the validity of the method: older animals (24 wk old) had 60% lower islet cell proliferation rates than younger rats (5 wk old), and partial (50%) pancreatectomy increased proliferation by 20%. In addition, cholecystokinin-8 treatment significantly stimulated proliferation in pancreatectomized rats only. In summary, heavy water labeling is a quantitative approach for measuring islet cell proliferation and testing therapeutic agents.

Low-grade central osteosarcoma of the mandible: a case study report

Low-grade central osteosarcoma is a rare type of osteosarcoma with peculiar clinical radiographic and microscopic features. The aim of this article is to report and discuss a case of low-grade central osteosarcoma in the mandible of a 42-year-old woman. The patient reported sensing mild pain and tooth mobility for a period of 4 years, despite continuous dental treatment. Radiographic evaluation showed a mixed radiopaque/radiolucenct lesion in the body, ramus, coronoid process, and condyle of the left side of the mandible. Destruction of the mandibular cortex in the area was also observed. After incisional biopsy, the patient underwent hemimandibulectomy. Microscopic findings showed a tumor exhibiting spindle cells with nuclear hyperchromasia and no mitotic activity, irregular osteoid formation, and soft tissue infiltration. The immunohistochemical analysis of the expression of Ki-67, Cyclin B1, and PCNA proteins (cellular proliferation markers) revealed a very low Ki-67+ and Cyclin B1+ cell index (mean 7% and 3%, respectively), but a moderate number of PCNA+ cells (mean 49%). The 2 years of clinical and imaging postoperative follow-up showed no evidence of recurrence. Clinicians should be aware of these lesions, because histopathologicially low-grade central osteosarcoma may be misinterpreted as fibrous dysplasia.

Evaluation of Ki-67 proliferation and apoptotic index before, during and after neoadjuvant chemotherapy for primary breast cancer

INTRODUCTION

Biological markers that reliably predict clinical or pathological response to primary systemic therapy early during a course of chemotherapy may have considerable clinical potential. This study evaluated changes in Ki-67 labeling index and apoptotic index (AI) before, during, and after neoadjuvant anthracycline chemotherapy.

METHODS

Twenty-seven patients receiving neoadjuvant FEC (5-fluorouracil, epirubicin, and cyclophosphamide) chemotherapy for operable breast cancer underwent repeat core biopsy after 21 days of treatment. Tissue from pre-treatment biopsy, day 21 and surgery was analysed for Ki-67 index and AI.

RESULTS

The objective clinical response rate was 56%. Eight patients (31%) achieved a pathological response by histological criteria; two patients had a near-complete pathological response. A reduction in Ki-67 index was observed in 68% of patients at day 21 and 72% at surgery; Ki-67 index increased between day 21 and surgery in 54%. AI decreased in 50% of tumours by day 21, increased in 45% and was unchanged in one patient; 56% demonstrated rebound increases in AI by the time of surgery. Neither pre-treatment nor post-chemotherapy median Ki-67 index nor median AI at all three time points or relative changes at day 21 and surgery differed significantly between clinical or pathological responders and non-responders. Clinical responders had lower median Ki-67 indices at day 21 (11.4% versus 27.0%, p = 0.02) and significantly greater percentage reductions in Ki-67 at day 21 than did non-responders (-50.6% versus -5.3%, p = 0.04). The median day-21 Ki-67 was higher in pathological responders (30.3% versus 14.1%, p = 0.046). A trend toward increased AI at day 21 in pathological responders was observed (5.30 versus 1.68, p = 0.12). Increased day-21 AI was a statistically significant predictor of pathological response (p = 0.049). A strong trend for predicting pathological response was seen with higher Ki-67 indices at day 21 and AI at surgery (p = 0.06 and 0.06, respectively).

CONCLUSION

The clinical utility of early changes in biological marker expression during chemotherapy remains unclear. Until further prospectively validated evidence confirming the reliability of predictive markers is available, clinical decision-making should not be based upon individual biological tumour marker profiles.

Tumour proliferation, angiogenesis, and ploidy status in human colon cancer

AIMS

Tumour angiogenesis is essential for carcinogenesis and facilitates the process of tumour development and metastasis. Vascular endothelial growth factor (VEGF) is a well characterised angiogenetic factor and is known to play a crucial role in new vessel development. To gain further insight into the effects of microvessel density and VEGF expression in colon cancer, their relation with tumour proliferation, ploidy status, and p53 expression was investigated in colon cancer.

METHODS

Tissue samples of 50 archived colon cancers were analysed by immunohistochemistry for VEGF, p53, and the endothelial cell marker, von Willebrand factor (VWF), using specific antibodies. The same samples were re-cut for flow cytometric studies to obtain S phase fraction (SPF) and ploidy status.

RESULTS

A positive significant correlation was found between SPF and angiogenesis. The median microvessel count in high SPF tumours was significantly higher than in low SPF ones. No association was found between VEGF expression and SPF. A positive correlation was found between ploidy status and p53 expression and microvessel count. Furthermore, a positive correlation was established between DNA ploidy, VEGF expression, and microvessel count.

CONCLUSION

This study provides evidence that in colon cancer, tumour growth may be stimulated by vascular supply, and the lack of a correlation between tumour cell proliferation and VEGF expression indicates that these two parameters may be regulated by separate mechanisms. Furthermore, the positive correlation between microvessel density, VEGF expression, and ploidy status provides more evidence that genetic alterations are involved in tumour angiogenesis.

Proliferative markers as prognostic and predictive tools in early breast cancer: where are we now?

In the last few decades, proliferative markers have been broadly evaluated as prognostic and predictive factors for early stage breast cancer patients. Several papers evaluating one or more markers have been published, often with contradictory results. As a consequence, there is still uncertainty about the role of these proliferative markers. The present paper critically reviews the current knowledge about the following markers: thymidine labeling index, S phase fraction/flow cytometry, Ki 67, thymidine kinase (TK), cyclins E, cyclin D, the cyclin inhibitors p27 and p21, and topoisomerase IIalpha. For each marker, the prognostic and predictive role was separately analyzed. Only papers published in English in peer-reviewed journals before June 2004 that include at least 100 evaluable patients were selected. In addition, the prognostic and predictive role of the proliferative markers had to be assessed through multivariate analyses. One hundred and thirty-two papers fulfilled these criteria and 159 516 patients were analyzed. Unfortunately, several methodological problems in the research to date prevent us from including any one of these proliferative markers among the standard prognostic and predictive factors. Early incorporation of translational research and new technologies with clinical trials are needed to prospectively validate biological markers and allow their use in clinical practice.

[Cytosolic pS2 levels and cellular proliferation in ER-positive and PgR-positive infiltrating ductal carcinomas of the breast]

OBJECTIVE

The trefoil factor 1 (TFF1/pS2) is an estrogen-induced molecule in breast tumours. We wanted to study its expression in ER+ and PgR+ infiltrating ductal carcinomas of the breast (IDCs), and to correlate it with other clinical-biological parameters and the outcome.

MATERIAL AND METHODS

Cytosolic pS2 levels were measured using an IRMA (CIS. Biointernational. France) in 170 tumors. Likewise we determined the cytosolic levels of cathepsin D and tissue-type plasminogen activator (t-PA), as well as the concentrations of the epidermal growth factor receptor (EGFR), erbB2 oncoprotein, CD44v5 and CD44v6 on cell surfaces. Also the tumour size, histological grade (HG), axillary lymph node involvement, distant metastasis, ploidy, DNA index and of cellular synthesis phase (SP) was taken in account.

RESULTS

The pS2-positive (> 5 ng/mg prot.) tumours showed higher concentrations of cathepsin D (p: 0.0043) and t-PA (p: 0.0089) than the pS2-negative ones. Likewise, they were less frequently HG3 (p: 0.0231), SP > 7 % (p: 0.0005) and SP > 14% (p:0.0014). During the follow-up time (r: 1-147; 50,1+/-31,7; median 37 months) the pS2-positive tumors showed a less number of recurrences (5/101 vs 6/69; p: 0.059) but not of deaths by the tumor (1/101 vs 2/69).

CONCLUSIONS

These results support an inverse relationship between pS2 positivity and cellular proliferation in IDCs and suggest a new role of this protein (different of the hormone dependence) in the biology of these breast carcinomas, while further studies will be required to establish the impact of this finding on their outcome.

Neoadjuvant Trastuzumab Induces Apoptosis in Primary Breast Cancers

Purpose

Greater understanding of the cellular response in trastuzumab-treated patients will provide insight into the clinical management of patients.

Patients and Methods

We performed a neoadjuvant trial in 35 patients with locally advanced HER-2/neu overexpressing breast cancers who received weekly trastuzumab given as a single agent for the first 3 weeks, followed by a combination of trastuzumab and docetaxel for 12 weeks before surgery. Sequential core biopsies were taken at baseline and within weeks 1 and 3 after the first dose of trastuzumab. Clinical response to trastuzumab was assessed by tumor measurements on day 22 before chemotherapy. Core biopsies were assessed by immunohistochemistry for cell cycle and proliferation (Ki67, p27, phosphorylated [p] -MAPK), apoptosis and survival (apoptotic index, p-Akt), epidermal growth factor receptor, and total and p-HER-2.

Results

There was early tumor regression with a median decrease of −20.0% (range. 0% to 60.4%) after only 3 weeks of trastuzumab, and eight patients (23%) had a partial response. Consistent with the clinical regressions, apoptosis was significantly induced (median increase from 3.5% to 4.7%; P = .006) within week 1, a 35% increase above baseline. No significant change in epidermal growth factor receptor score was observed in week 1, without changes in total or p-HER-2 expression. Tumors with high baseline Ki67 were less likely to respond (P = .02).

Conclusion

In primary breast cancers, trastuzumab substantially induces apoptosis, providing a molecular explanation for both its therapeutic efficacy and its successful combination with cytotoxic chemotherapy.

Prognostic implication of p53 protein expression in relation to nuclear pleomorphism and the MIB-1 counts in breast cancer

BACKGROUND

A close correlation of the p53 protein expression to nuclear pleomorphism and proliferative activity in breast cancer has been reported. The prognostic implications of p53 protein expression, however, in relation to nuclear pleomorphism and proliferative activity in breast cancer remain controversial.

PATIENTS AND METHODS

Nuclear pleomorphism and immunohistochemical reactivity for p53 protein and MIB-1 were evaluated on formalin-fixed paraffin-stored sections from 250 patients with breast cancer for whom the median follow-up duration was 6.4 years.

RESULTS

p53 protein expression was positive in 66 (26.4%) of 250 cases. Nuclear pleomorphism was grade I or II in 169 (67.6%) cases and grade III in 81(32.4%)cases. The MIB-1 counts were more than 10% in 102 (40.8%) cases and less than 10% in 148 (59.2%) cases. There was a close correlation between p53 protein expression and nuclear pleomorphism (p<0.0001) and between p53 protein expression and MIB-1 counts (p<0.0001). Univariate analyses showed the 66 cases with positive p53 protein expression to have a significantly (p=0.0284) worse disease free survival (DFS) than the 184 cases with negative p53 protein expression. A multivariate analysis, however, on the variables including all of p53 protein expression, nuclear pleomorphism and MIB-1 counts indicated the MIB-1 counts (p=0.0041) as well as the lymph node status to be independently significant factors for DFS, while neither p53 protein expression nor nuclear pleomorphism were independently significant factors for DFS.

CONCLUSION

The present study demonstrated that the p53 protein expression, nuclear pleomorphism and MIB-1 counts all demonstrated prognostic significance for breast cancer, while the most significant prognostic indicator among these three biological parameters was the MIB-1 counts.

Validation of the use of proliferation markers in canine neoplastic and non-neoplastic tissues: comparison of KI-67 and proliferating cell nuclear antigen (PCNA) expression versus in vivo bromodeoxyuridine labelling by immunohistochemistry

In order to evaluate the suitability of Ki-67 and proliferating cell nuclear antigen (PCNA) for determination of proliferative activity, the immunohistochemically determined nuclear expression of these antigens in canine non-neoplastic and neoplastic tissues was compared with the results of in vivo bromodeoxyuridine (BrdU) labelling, which - by measurement of the fraction of S-phase cells - is considered as the standard in the analysis of proliferative activity. The samples investigated consisted of non-neoplastic mammary and lymphoid tissues, and of benign and malignant (primary/metastatic) mammary tumours, and malignant lymphomas. Great regional heterogeneity prevented determination of an overall labelling index (LI) in normal lymphoid tissues. In the remaining combined group of samples, LI values were significantly ranked in the order PCNA>Ki-67>BrdU. However, the correlation of Ki-67 or PCNA as compared to BrdU LI values was only moderate in the combined group [approximately 0.5, Spearman rank test] as well as in most subgroups, whilst it was very poor in the group of primary mammary cancers. These observations indicate that Ki-67 or PCNA LIs as markers of proliferation do not evenly match in vivo BrdU labelling.

Prognostic and predictive role of proliferation indices in adjuvant therapy of breast cancer

In breast cancer, proliferative activity represents one of the biologic processes most thoroughly investigated for its association with tumor progression. In addition to the mitotic activity component of pathologic grading systems, several proliferation indices have provided independent information on prognosis and response to specific treatments in large retrospective studies. Recently, results from treatment protocols prospectively planned to test the clinical utility of proliferative activity have indicated that tumor cell proliferation markers identify two subsets among patients with lymph node-negative cancers: 1) those at a very low risk of relapse and 2) those who will benefit from regimens including antimetabolites. Future efforts should compare the prognostic accuracy of different proliferation markers, confirm preliminary evidence of a relationship between proliferation and response to specific systemic treatments, and standardize assay techniques to facilitate their transfer to general oncology practice.

Multiparametric flow cytometric analysis in a breast cancer cell line (MCF-7)

OBJECTIVE

To investigate whether multiparameter flow cytometric analysis of solid tumor specimens, including gynecologic tumors, which were stained triply with phycoerythrin (PE), fluorescein isothiocyanate (FITC) and propidium iodide (PI), can be performed simultaneously without interference from normal diploid cell populations and spectral overlap on a standard flow cytometer.

METHODS

MCF-7 breast cancer cell lines and heterogeneous cell populations mixed with MCF-7 cells and human peripheral blood lymphocytes (PBL) were fixed with 1% paraformaldehyde and permeabilized with 100% methanol. Cytokeratin and several proliferation-associated cellular antigens (proliferating cell nuclear antigen (PCNA), p53, c-erbB/2 and c-myc) were labeled with PE and FITC, which was followed by DNA staining using PI. These labeled cells were measured on a standard FACScan flow cytometer equipped with a 488 nm single laser.

RESULTS

The coefficient of variation (CV) of the G0G1 peak of MCF-7 cells was 4.3 and the cell cycle phase fractions of G0G1, S and G2M were 44.9, 45.9 and 9.2%, respectively. Fluorescein isothiocyanate, PE and PI fluorescences were detected without interference. The MCF-7 cells expressed cytokeratin, PCNA, p53, c-erbB/2 and c-myc antigen. In the heterogeneous population of MCF-7 cells mixed with PBL, two cellular populations were clearly separated into diploid PBL and aneuploid MCF-7 cells without interference. The CV of G0G1 peak of PBL was 2.3 and the G0G1, S and G2M phase fractions were 85.5, 2.7 and 11.8%, respectively. The DNA index of MCF-7 cells was 1.7, which indicated that the MCF-7 cell line was composed of tumor cells with aneuploid DNA. The CV of the G0G1 peak of the MCF-7 cells was 4.2, and the cell cycle phase fractions were 47.5% for G0G1, 42.3% for S, and 10.2% for G2M. The MCF-7 cells expressed cytokeratin, but the PBL did not.

CONCLUSIONS

Multiparameter flow cytometer analysis was useful to determine DNA ploidy status, phase fraction of the cell cycle and expression of cellular antigens and selective cytokeratin expression allowed epithelial originated tumor cells to be differentiated from normal stromal cells. This analysis could be performed without interference of spectral overlaps of fluorochromes using software-based algorithmic compensation of spectral overlaps. Thus, this method offers new possibilities for multiparameter flow cytometric analysis and its use should be extended to future studies of the diagnosis, treatment and prediction of prognosis of the neoplasm.

Prognostic significance of tumor cell proliferation analyzed in fine needle aspirates from primary breast cancer

The objective of this study was to analyze the role of proliferating fraction (PF) measured with Ki-67/MIB-1 antibody in a large series of preoperative fine-needle aspirate (FNA) biopsies as a prognosticator of disease recurrence. The study comprised 732 patients who all had a conclusive cytological diagnosis of breast cancer. The follow-up time ranged from 1.2 to 10.2 years with a median of 5.7 years. In multivariate analysis Ki-67/MIB-1 value was a strong (p < 0.001) significant, prognosticator of disease recurrence free interval (DRFI) independent of lymph node status, progesterone receptor content, and tumor size. In the subgroup analysis of 430 node-negative patients the distant recurrence-free rate after 5 years was 94.4% in patients with Ki-67/MIB-1 value < 15% compared to 88.7% in patients with Ki-67/MIB-1 value > or = 15% (p = 0.03). Test of the interaction between tumor size and the value of PF revealed a p-value of 0.06. If the patients, in addition, had a tumor size >20 mm the distant recurrence-free rate after 5 years was 93.2% if Ki-67/MIB-1 < 15% compared to 80.7% in patients with Ki-67/MIB-1 value > or = 15%. This difference was statistically significant (p < 0.01). For patients with tumors <20mm Ki-67/MIB-1 value did not add any prognostic information. In the subgroup of 302 node-positive patients the distant recurrence-free rate after 5 years was 86.0% in patients with Ki-67/MIB-1 value < 15% compared to 70.6% in patients with Ki-67/MIB-1 value > or = 15% (p < 0.01). We conclude that PF assessed by Ki-67/MIB-1 antibodies in preoperative FNA biopsies has a significant prognostic value independent of lymph node status, PgR status and tumor size. To our knowledge, this is the first study demonstrating PF, which can contribute prognostic information when analyzed in preoperative smears.

MIB-1 labeling index in feline dysplastic and neoplastic mammary lesions and its relationship with postsurgical prognosis

Samples from feline normal, dysplastic, and neoplastic mammary tissues were used to investigate the usefulness of MIB-1 labeling index (MIB-1 I) as a prognostic indicator. Forty-eight queens bearing invasive carcinomas were included in a 2-year follow-up study. Mammary lesions were classified according to the World Health Organization system, and invasive carcinomas were further graded on the basis of the degree of tubule formation, the degree of nuclear and cellular pleomorphism, and mitotic count. Additional sections were immunostained using MIB-1 antibody, and MIB-1 I was expressed as a percentage of positive nuclei. In normal mammary gland tissues, the mean MIB-1 I was <1%. A low proliferation rate was found in all mammary adenosis and in situ carcinomas, and the highest rates were observed in feline mammary hypertrophy and invasive carcinomas. Twenty-one (43.7%) of the queens bearing invasive carcinomas were still alive at the end of the trial, and 27 (56.2%) had died. The MIB-1 I was not significantly correlated with clinical outcome, age, histologic type, or grading of the tumors, but a borderline correlation was observed with invasion of lymphatic vessels. Univariate analysis showed that high MIB-1 I was also not associated with decreased overall survival, whereas the grading system of the tumors had high predictive value (P = 0.0040) for postsurgery survival. The lack of correlation between MIB-1 I and postsurgery survival suggests that this marker alone is not sufficient to determine a correct prognosis in feline mammary carcinomas, even if it is a useful proliferation marker.

Comparison between different cell kinetic variables in human breast cancer

Cell kinetics holds a prominent role among biological factors in predicting clinical outcome and response to treatment in neoplastic patients. Different cell kinetic variables are often considered as valid alternatives to each other, but the limited size of case series analysed in several studies and the lack of simultaneous determinations of all the variables on the same tumours do not justify this conclusion. In the present study, the correlation between [3H]thymidine labelling index ([3H]dT LI), flow cytometric S phase cell fraction (FCM-S) and Ki-67 immunoreactivity (Ki-67/MIB-1) was verified and the type of correlation with the most important clinical, pathological and biological patient and tumour characteristics was investigated in a very large series of breast cancer patients. Ki-67/MIB-1, FCM-S and [3H]dT LI were determined in 609, 526 and 485 patients, respectively, and all three cell proliferation indices were evaluated in parallel on the same tumour in a series of 330 breast cancer patients. All the cell kinetic determinations were performed within the context of National Quality Control Programmes. Very poor correlation coefficients (ranging from 0.37 to 0.18) were observed between the different cell kinetic variables determined in parallel on the same series of breast cancers. Moreover, Ki-67/MIB-1 and FCM-S showed a significant relationship with histological type, grade and tumour size, whereas statistically significant correlations were not observed for [3H]dT LI. In conclusion, the results show that the different cell kinetic variables provide different biological information and cannot be considered as alternatives to each other.

Prognostic comparative study of S-phase fraction and Ki-67 index in breast carcinoma

AIMS

To investigate the prognostic value of recently proposed flow cytometric S-phase fraction (SPF) variables (average SPF and SPF tertiles) compared with conventional SPF, and to compare the one with the best predictive value with the immunohistochemical Ki-67 index in breast carcinoma.

METHODS

A short term follow up study (median, 39.6 months) of a large series of patients (n = 306) was conducted. DNA ploidy was analysed on fresh/frozen tumour samples by flow cytometry, and the SPF was calculated from the DNA histogram using an algorithm. The Ki-67 index was assessed on paraffin wax embedded material by immunohistochemistry (cut off point, 10%). The two methods were compared by means of kappa statistics, and the prognostic significance of both in relation to disease free survival (DFS) and overall survival (OS) was determined.

RESULTS

SPF and Ki-67 analysis was performed on 234 (76.5%) and 295 (96.4%) tumours, respectively. The two assessments were simultaneously available in 230 cases. All SPF variables analysed in the whole series significantly correlated with disease evolution, with the conventional median SPF (cut off point, 6.1%) showing the highest predictive value in relation to both DFS (p = 0.0001) and OS (p = 0.0003). SPF tertiles and median SPF evaluated according to DNA ploidy status had no prognostic significance. The Ki-67 index showed a trend in relation to DFS (p = 0.086) that did not reach significance, and no correlation with OS was found (p = 0.264). The comparative analysis of SPF and Ki-67 revealed some agreement between the two methods (agreement, 69.13%; kappa statistic, 0.3844; p < 0.001), especially in the subgroup of diploid tumours.

CONCLUSIONS

Flow cytometric SPF is a better prognosticator than the Ki-67 index, but only SPF variables applied in the whole series show potential clinical usefulness.

Prognostic and predictive factors in breast cancer

Around 570 000 women develop breast cancer worldwide. In the U.K. it affects 33 000 women and causes 16 000 deaths each year. Treatment of early breast cancer is surgical, comprising breast conserving surgery (followed by radiotherapy) for small unifocal tumours, or mastectomy for larger or multifocal tumours. Survival of patients with breast cancer depends on two different types of prognostic factors: tumour size reflecting how long the tumour has been present, and biological factors (i.e. grade) which represent tumour aggressiveness. In women with a tumour that has adverse features predicting early recurrence (i.e. lymph node positivity, large size, high grade) adjuvant systemic chemo- or hormonal therapy is given to reduce the risk of relapse. Chemotherapy is given to pre-menopausal women for oestrogen receptor negative post-menopausal breast cancer, whereas hormone therapy is reserved for oestrogen receptor positive cancer. Since 50% of patients will never relapse, identification of which women are at high risk of recurrence is necessary so as to offer treatment with adjuvant therapy. The use of hormone therapy and chemotherapy has been aided by factors predicting the likelihood of response, e.g. oestrogen receptor status. The value of newer prognostic and predictive markers is addressed.

Clinical relevance of T1-S, an oncogene-inducible, secreted glycoprotein of the immunoglobulin superfamily, in node-negative breast cancer

Axillary lymph node-negative breast cancer patients have a low risk for disease recurrence, and the majority of these patients are cured by surgery alone. However, accurate identification of that 30% of node-negative patients who are at high-risk for relapse and who might therefore benefit from adjuvant systemic therapy has not been possible using traditional histomorphological and clinical prognostic factors alone. Identification of novel tumor-associated molecules may therefore provide a basis for a better understanding of and eventually for an interference with disease progression. We have recently reported on tumor-associated RNA up-regulation of the secreted, soluble T1-S receptor in node-negative breast cancer. In the present study we analyzed the tumor-associated level of the T1-S receptor using semiquantitative immunohistochemistry in a collective of 102 node-negative breast carcinomas to study its clinical relevance. A high T1-S immunoreactivity score indicating T1-S overexpression was observed in 58 of 102 (57%) cases. The T1-S score was independent of the tumor size, type, grade, steroid hormone receptor status, and the proliferation rate determined by monoclonal antibody against KI-67 protein (MIB1) immunohistochemistry. In univariate and multivariate analysis of disease-free survival, a high T1-S score (p = 0.003) and a low MIB1 score (p = 0.001) were the only parameters that were highly significantly associated with an improved disease-free survival period. We conclude that T1-S receptor overexpression is a novel and independent tumor biological factor that may be associated with reduced progression of lymph node-negative breast cancer.

Prognostic significance of immunohistochemically localized biomarkers in stage II and stage III breast cancer: a multivariate analysis

BACKGROUND

The aim was to investigate the expression of a panel of biomarkers such as prolactin (PRL), p53, Bcl-2, c-erb B2, Ki-67, CD44, and factor VIII-related antigen (FVIII-RA) in primary tumors of stage II and stage III breast cancer and its correlation with disease prognostication.

METHODS

The streptavidin-biotin peroxidase complex technique was used for the detection of these antigens. Cytoplasmic staining pattern was observed for PRL, Bcl-2, and Ki-67. Staining pattern for p53 was nuclear. Membranous and/or cytoplasmic staining was noted for c-erb B2 and CD44. Microvessel staining was noted for FVIII-RA.

RESULTS

Of the 93 primary breast tumors analyzed, positivity for PRL was noted in 82%, for p53 in 56%, for Bcl-2 in 73%, for c-erb B2 in 68%, and for Ki-67 and CD44 in 78% each. The microvessel count (MVC) for FVIII-RA ranged from 0.0 to 29.0, with a median of 6.0, which was used as a cutoff. MVC > or = 6.0 was noted in 51% of breast tumors. With increasing tumor size, the higher frequency of positivity of MVC > or = 6.0 (P = .0001), CD44 (P = .001), PRL (P = .002), and c-erb B2 (P = .008), and higher frequency of Bcl-2 negativity (P = .033), was noted. In stage III patients, a higher positivity of the following biomarkers was noted, compared with stage II patients: MVC > or = 6.0 (P = .0004), PRL (P = .0002), c-erb B2 (P = .001), and CD44 (P = .005). Further, Bcl-2 positivity was significantly lower in patients with stage III disease compared with those with stage II disease (P = .024). In patients with nodal involvement, the frequency of c-erb B2 (P = .006), MVC > or = 6.0 (P = .011), and PRL (P = .032) was higher than in those without nodal involvement. Moreover, in these patients, with the increase in the number of involved lymph nodes, there was a significant increase in frequency of CD44+ (P = .0004) and PRL+ (P = .013) tumors. Abnormal expression of one biomarker was seen in 7% of tumors, of two biomarkers in 4%, of three in 15%, of four in 19%, of five in 28%, of six in 20%, and of all seven biomarkers in 7% of tumors. The frequency of an increasing number of biomarkers coexpressed was higher in stage III patients compared with stage II patients (P = .00003). In the total number of patients (n = 93), tumors with Bcl-2 negativity (P = .00001), MVC > or = 6.0 (P = .001), PRL positivity (P = .02), and CD44 positivity (P = .034) had a significantly poorer overall survival (OS) compared with their respective counterparts. In stage II patients (n = 40), only p53 expression was significantly associated with reduced relapse-free survival (P = .009) and OS (P = .040). In multivariate analysis, p53 expression was an independent prognostic factor that influenced relapse-free survival (P = .034) of stage II breast cancer patients. However, it failed to attain statistical significance for OS. In stage III patients (n = 53), tumors with Bcl-2 negativity (P = .0005) and MVC > or = 6.0 (P = .039) had a significantly poorer OS compared with their respective counterparts. In multivariate analysis of stage III patients, Bcl-2 was the only independent prognostic factor (P = .001) for predicting OS. There was a significant association between coexpression of the biomarkers and OS (P = .001). The OS rates decreased with the increase in number of abnormally expressed biomarkers.

CONCLUSIONS

p53 expression in primary tumors was an independent prognostic factor that influenced relapse-free survival in patients with stage II disease. In stage III patients, lack of Bcl-2 expression was independently associated with a poor prognosis and, thus, may be an indicator of aggressive phenotype.

The prognostic value of proliferation indices: a study with in vivo bromodeoxyuridine and Ki-67

Proliferation indices are intended to help patients and clinicians make treatment decisions. We have previously demonstrated that a proliferation index based on in vivo labeling of S-phase cells with bromodeoxyuridine (BrdUrd) correlates with Ki-67 labeling index (LI). We now compare the prognostic value of these indices. With written consent, we gave 129 women with biopsy confirmed breast cancer 200 mg/M2 BrdUrd during 30 min immediately preceding surgery. We used IU-4 anti BrdUrd antibody to count the immunohistochemical labeling index (LI) of DNA-incorporated BrdUrd in 2,000 cells and MIB-1 to count Ki-67 (118 cases). Patients received standard surgical and adjuvant treatment. No patients were lost to follow-up and patients were followed a minimum of 2 (median 5.1) years. We compared survival and recurrence in tumors with high vs low labeling indices. We found that women in the low BrdUrd LI group had better disease free survival (92% vs 67% 5-yr DFS p = 0.001) and overall survival (94% vs 70% 5-yr OS, p = 0.0001) than those with a high LI. In comparison, a low Ki-67 index predicted better OS (87% vs 80% 5-yr OS, p = 0.020) and a trend for better DFS (84% vs 72% DFS p = 0.055). The apparent superiority of BrdUrd LI over Ki-67 LI is likely due to chance (p = 0.18). In multivariate survival analyses we found that BrdUrd LI proliferative index significantly improves prediction of DFS or OS even when node status, age or tumor size is in the model. We conclude that markers of proliferation are useful adjuncts in predicting patient prognosis.

Risk-group discrimination in node-negative breast cancer using invasion and proliferation markers: 6-year median follow-up

Factors reflecting two major aspects of tumour biology, invasion (urokinase-type plasminogen activator (uPA), plasminogen activator inhibiter (PAI-1), cathepsin D) and proliferation (S-phase fraction (SPF), Ki-67, p53, HER-2/neu), were assessed in 125 node-negative breast cancer patients without adjuvant systemic therapy. Median follow-up time was 76 months. Antigen levels of uPA, PAI-1 and cathepsin D were immunoenzymatically determined in tumour tissue extracts. SPF and ploidy were determined flow-cytometrically, Ki"'-67, p53, and HER-2/neu immunohistochemically in adjacent paraffin sections. Their prognostic impact on disease-free (DFS) and overall survival (OS) was compared to that of traditional factors (tumour size, grading, hormone receptor status). Univariate analysis determined PAI-1 (P < 0.001), uPA (P = 0.008), cathepsin D (P = 0.004) and SPF (P = 0.023) as significant for DFS. All other factors failed to be of significant prognostic value. In a Cox model, only PAI-1 was significant for DFS (P < 0.001, relative risk (RR) 6.2). In CART analysis for DFS, the combination of PAI-1 and uPA gave the best risk group discrimination. For OS, PAI-1, cathepsin D, tumour size and ploidy were statistically significant in univariate, but PAI-1 was the only independently significant factor in Cox analysis (P < 0.001, RR 8.9). In particular, this analysis shows that PAI-1 is still a strong and independent prognostic factor in node-negative breast cancer after extended 6-year median follow-up.

Prognostic significance of Ki-67 and topoisomerase IIalpha expression in infiltrating ductal carcinoma of the breast. A multivariate analysis of 863 cases

To evaluate the prognostic relevance of Ki-67 and topoisomerase IIalpha expression in relation to tumor stage, grade, and hormone receptor content, 942 ductal infiltrating carcinomas of the breast were examined by means of the monoclonal antibodies Ki-S11 (Ki-67) and Ki-S4 (topoisomerase IIalpha). pS2, c-erbB2, and p53 were additionally considered as prognostic variables. The median follow-up time was 149 months. Eight-hundred-and-sixty-three tumors reacted with Ki-S11 and Ki-S4; the labeling indices of the two antigens were closely associated (r = 0.93). Both correlated positively with the tumor size, c-erbB2, and p53 expression, and negatively with patient age, hormone receptor content, and pS2 immunostaining. In the univariate analysis, Ki-S11 and Ki-S4 scores, nodal status, tumor size, tumor grade, and progesterone receptor content strongly predicted both overall and metastasis-free survival (p < 0.00001). Estrogen receptor status, p53, and c-erbB2 were of minor significance. Concerning overall survival, multivariate Cox regression analysis selected a Ki-S4 score >25% (p < 0.00001) next to the nodal status, and before tumor size, progesterone receptor content, and patient age. Independent predictors of the occurrence of distant metastases were nodal status, Ki-S4, tumor size, grade 1, and progesterone receptor negativity, in that order. The Ki-S11 score was of independent prognostic significance only if examined as a continuous variable. We conclude that topoisomerase IIalpha expression as assessed by monoclonal antibody Ki-S4 may add valuable information to current prognostic models for breast cancer. Its predictive value appears to be essentially related to the proliferative activity of tumor cells.

S-phase fraction and breast cancer--a decade of experience

During the past decade, more than 300 articles, abstracts, and book chapters have been published about S-phase fraction (SPF) determined by DNA flow cytometry and its clinical utility for patients with breast cancer. However, the use of SPF for making treatment decisions for breast cancer patients remains controversial. After reviewing 273 published articles, we conclude: 1) Despite different techniques and cutpoints, correlations between SPF and other prognostic markers are relatively consistent across studies; higher SPF is generally associated with worse tumor grade, absence of steroid receptors, larger tumors, and positive axillary lymph nodes. 2) Higher SPF is generally associated with worse disease-free and overall survival in both univariate and multivariate analyses; SPF values from laboratories that have conducted validation studies can be used, in combination with other factors, to estimate the prognosis of patients with primary breast cancer. 3) There is considerable variability among laboratories regarding assay methodology, cell-cycle analysis techniques, and cutpoints for classifying and interpreting SPF; use of SPF values from different laboratories is problematic, and there remains a need for standardization of these processes and well-designed confirmation studies. We conclude that measurement of SPF does have clinical utility for patients with breast cancer, but standardization and quality control must be improved before it can be routinely used in community settings.

Prognostic value of vascular density and cell proliferation in breast cancer patients

We measured microvessel density and cell proliferation index in 84 breast cancers using survival analysis to find out their prognostic value. Immunohistochemistry was applied using antibody to factor VIII-related antigen as a marker for microvessels and MIB-1 antibody to stain proliferating cells. We were not able to show any difference in survival with a mean follow-up of 10.3 years between patients with high and low microvessel count or cell proliferation index. Vascular density did not correlate with the cell proliferation rate (p = 0.4). However, patient age correlated negatively with the cell proliferation index of the tumor (p = 0.0009). There was no significant difference both in microvessel count and in cell proliferation between patients with lymph node metastasis and node negative patients. This result questions the usefulness of vascular density and cell proliferation rate as prognostic markers in breast cancer.

Immunologic proliferation marker Ki-S2 as prognostic indicator for lymph node-negative breast cancer

BACKGROUND

Proper treatment of lymph node-negative breast cancer depends on an accurate prognosis. To improve prognostic models for this disease, we evaluated whether an immunohistochemical marker for proliferating cells, Ki-S2 (a monoclonal antibody that binds to a 100-kd nuclear protein expressed in S, G2, and M phases of the cell cycle), is an accurate indicator of prognosis.

METHODS

We studied 371 Swedish women with lymph node-negative breast cancer; the median follow-up time was 95 months. The fraction of tumor cells in S phase was assessed by flow cytometry, and tumor cell proliferation was measured immunohistochemically with the monoclonal antibodies Ki-S2 and Ki-S5 (directed against the nuclear antigen Ki-67). A combined prognostic index was calculated on the basis of the S-phase fraction, progesterone receptor content, and tumor size.

RESULTS

In multivariate analyses that did or did not (263 and 332 observations, respectively) include the S-phase fraction and the combined prognostic index, the Ki-S2 labeling index (percentage of antibody-stained tumor cell nuclei) emerged as the most statistically significant predictor of overall survival, disease-specific survival, and disease-free survival (all two-sided P<.0001). In the risk group defined by a Ki-S2 labeling index of 10% or less, life expectancy was not statistically significantly different from that of age-matched women without breast cancer, whereas the group with a high Ki-S2 labeling index had an increased risk of mortality of up to 20-fold.

CONCLUSIONS

Cellular proliferation is a major determinant of the biologic behavior of breast cancer. Prognosis is apparently best indicated by the percentage of cells in S through M phases of the cell cycle. Measurement of the Ki-S2 labeling index of a tumor sample may improve a clinician's ability to make an accurate prognosis and to identify patients with a low risk of recurrence who may not need adjuvant therapy.

Comparison of the Ki-67 score and S-phase fraction as prognostic variables in soft-tissue sarcoma

Immunohistochemically determined Ki-67 scores and flow cytometrically determined S-phase fractions were successfully evaluated from the primary tumours of 123 patients with soft-tissue sarcoma. All patients had either limb or superficial trunk tumours. Ki-67 score correlated strongly with ploidy, S-phase fraction and grade. Ki-67 did not correlate with the size of the primary tumour. When analysed as a continuous variable, Ki-67 was a stronger predictor of both metastasis-free survival and disease-specific overall survival (P = 0.003 and 0.04 respectively) than was the S-phase fraction (P = 0.06 and 0.07 respectively). We tested the relevance of different cut-point values by dividing the whole material into two parts at every 10% (e.g. 10% of patients vs. the remaining 90%, 20% vs. 80%, etc.). We counted the relative risk and confidence interval at all these cut-off points. Ki-67 had good prognostic discriminating power irrespective of the cut-point value, but S-phase fraction lost its prognostic power at higher cut-point values. In conclusion, we found that Ki-67 is a useful prognostic tool in the treatment of soft-tissue sarcoma patients irrespective of the cut-point value. S-phase fraction can be used at lower cut-point values.

Ki-67 index as indicator of the post-surgical prognosis in feline mammary carcinomas

Forty-eight feline mammary carcinomas (FMC) were resected surgically from 48 cats to determine whether the Ki-67 index (Ki-67I) would provide an indication of the post-surgical survival time (PST). Twenty-four cats (50 per cent) were still alive (group A) one year after surgery, whilst 24 (50 per cent) (group B) had died. Formalin-fixed, paraffin wax-embedded histological sections were immunostained with a monoclonal antibody to Ki-67 (MIB-1) and at least 1000 nuclei in eight to 10 representative fields were counted. The Ki-67I was expressed as the percentage of positive nuclei. In FMC, the Ki-67I ranged from 7.5 to 49.7 (24.8+/-9.5). A statistically significant difference (P = 0.000006) in the Ki-67I was found between group A and group B cats. No other statistically significant differences were found between these groups. The Ki-67I did not correlate with age or different histological type, according to the WHO classification. A Ki-67I cut-off of 25.2 represents a useful tool for identifying FMC with a more aggressive course.

MIB-1 labelling index is an independent prognostic marker in primary breast cancer

The proliferative activity of a tumour is considered to be an important prognostic factor in primary breast cancer. We have investigated the prognostic value of the MIB-1 labelling index in 341 patients with primary breast cancer and compared the results with the S-phase fraction in 220 patients of the same cohort. All patients were treated in one hospital and had a median follow-up of 128 months. No correlation between MIB-1 labelling and S-phase fraction could be demonstrated. MIB-1 had prognostic value for disease-free survival in the whole group of patients (P < 0.001) and in the node-negative subgroup (P < 0.001). In multivariate analysis, MIB-1 was an independent prognostic factor (P = 0.004) besides axillary lymph node status (P = 0.001). In univariate analysis high S-phase fraction was associated with decreased overall survival (P = 0.04); however, not in multivariate analysis. Moreover, S-phase fraction had a borderline prognostic significance for post-relapse survival in multivariate analysis (P= 0.08). Thus, in conclusion, the growth fraction of a tumour as determined by the MIB-1 labelling index is an important prognostic factor in patients with primary breast cancer.

Immunohistochemical detection of Ki-67 and PCNA in canine mammary tumors: relationship to clinical and pathologic variables

The objectives of this study were to measure the proliferation indices in canine mammary tumors using immunohistochemical detection of Ki-67 and proliferating cell nuclear antigen (PCNA), to determine the relationship of these antigens to clinical and pathologic variables, and to investigate the usefulness of these antigens as prognostic indicators. Ninety-six female dogs with 115 primary nonmetastasized spontaneous mammary tumors and dysplasias were included in the study. Immunostaining was performed using MIB-1 and PC10 monoclonal antibodies against Ki-67 and PCNA, respectively. Ki-67 and PCNA proliferation indices were determined. Dogs were followed for 18 months, with clinical examinations every 3-4 months. There was a significant correlation between Ki-67 and PCNA indices in the dogs with dysplasias and benign tumors but not in the dogs with malignant tumors. The clinical stage at first presentation was related to the proliferative index measured with Ki-67 but not to that measured with PCNA. Proliferation indices were significantly lower in the nonmalignant tumors and dysplasias than in the malignant tumors. In malignant tumors, the PCNA index had a positive correlation with the histologic malignant grade and the nuclear grade. High index values of Ki-67 were positively correlated with metastasis, death from neoplasia, low disease-free survival rates, and low overall survival rates. PCNA displayed no significant association with these variables. Multivariate analyses concerning metastasis, disease-free survival, and overall survival revealed that the Ki-67 index had prognostic value.

Rapid and prognostically valid quantification of immunohistochemical reactions by immunohistometry of the most positive tumour focus. A prospective follow-up study on breast cancer using antibodies against MIB-1, PCNA, ER, and PR

The prognostic significance of immunohistochemical markers for cell proliferation [MIB-1, proliferating cell nuclear antigen (PCNA)] and hormone receptor analysis [oestrogen receptor (ER), progesterone receptor (PR)] was tested by means of immunohistometry in a series of 103 breast cancer patients in comparison with the lymph node status N, the tumour size T, histomorphological grading, and the biochemical ER and PR status. Immunohistochemical reactions were performed on 2 microns sections from paraffin-embedded tissue, using an indirect peroxidase method. The proportion of immunostained tumour cell nuclei was determined using a TV-image analysis system. Measurements were performed using a 20 x objective on 40 viewing fields (1.94 mm2, MIB-1 and PCNA) or 20 viewing fields (0.97 mm2, ER and PR). The mean immunopositivity of all viewing fields and the value of the most immunopositive viewing field (MIB-1max, PCNAmax, PRmax, ERmax) were calculated. The mean values and the maximal values were highly correlated (r = 0.903, P < 0.001). After 1:2:1 quantilization, 84.2 per cent of the 412 single measurements revealed mean and maximal values in the same category (P < 0.0001). For each of the four immunohistochemical markers, the prognostic significance of the maximal values was higher than that of the mean values. The highest prognostic significance was found for MIC-1max (P = 0.0002), followed by PRmax (P = 0.0046), ERmax (P = 0.0154), and PCNAmax (P = 0.0161). From the results of a Cox model, a 'prognostic index (PI)' was developed, ranging from -1 to 8: PI = 2 x N + T + MIB-1max-PRmax. The four groups of patients with PI values of < 2, 2-3, 4-5, and > 5 revealed significantly different 7.5-year survival probabilities (P < 0.0001). The simplicity of the PI makes it a clinically useful, routinely applicable, and understandable parameter in the surgical pathology of breast carcinoma.

How should PCNA be assessed? Total of stained cells or only the most intensely stained ones?

OBJECTIVE

This study aimed to analyse whether a marker of proliferative activity (PCNA) could provide a prognosis of tumor evolution and to determine whether different interpretation criteria could alter the results.

METHOD

The presence of PCNA in 59 patients of state II (T2 N0.1 M0) mammary carcinoma was determined.

RESULT

Numerical proportions of total and intensely stained cells were established. These data were compared with anatomopathological parameters. A significant association between higher cyclin values and worse histological and nuclear grading was encountered, particularly in patients with a "negative axilla" using the PCNA index. Cyclin values were not significant in relation to any parameters when indices from the intensely stained cells were considered exclusively.

CONCLUSION

Higher nuclear (NG3) and histological (HGIII) grading, associated with a high PCNA index (> 50), distinguish high-risk patients, and it is more appropriate considering all the stained cells as representative of PCNA indices, thus reflecting tumor aggressiveness.

Prognostic role of clinical, pathological and biological characteristics in patients with locally advanced breast cancer

Forty-two patients with clinical stage IIIA or IIIB breast cancer were treated with neoadjuvant chemotherapy followed by mastectomy and radiotherapy. The median follow-up was 32 months (range 10-72 months) and the median time to progression was 17 months (range 10-30 months). A multivariate analysis showed that a longer disease-free survival (DFS) was related to more chemotherapy cycles given (P = 0.003), a better pathological response to chemotherapy (P = 0.04) and fewer positive axillary lymph nodes (P = 0.05). A better overall survival (OS) was related to more chemotherapy cycles given (P = 0.03) and better pathological response to chemotherapy (P = 0.04). In patients with residual tumour after neoadjuvant chemotherapy, high levels of staining for Ki-67 was correlated with a worse DFS (P = 0.008). Other biological characteristics, including oestrogen receptor status, microvessel density (CD31 staining), P-glycoprotein (P-gp) staining and nuclear accumulation of p53, were not independent prognostic factors for either DFS or OS. If both P-gp and p53 were expressed, DFS and OS were worse in the uni- and multivariate analysis. The preliminary results of this phase II study suggest that coexpression of P-gp/p53 and a high level of staining for Ki-67 after chemotherapy are associated with a worse prognosis, and that prolonged neoadjuvant chemotherapy and the attainment of a pathological complete remission are important factors in determining outcome for patients with this disease.

Sulindac sulfide induces several subpopulations of colon cancer cells, defined by PCNA/Ki-67 and DNA strand breaks

We assessed the effect of sulindac sulfide (SS), a colon cancer chemopreventive agent, on the proliferation and apoptosis in the colon cancer cell lines HCT-15 and HT-29. We applied a triparameter flow cytometric analysis that simultaneously determined DNA content, expression of Ki-67 or proliferating cell nuclear antigen (PCNA), and extent of DNA strand breaks by TUNEL (TdT-mediated dUTP nick end labeling). HCT-15 and HT-29 cells were exposed to SS 200 microM and 175 microM, respectively, for up to 72 h. As expected, SS inhibited proliferation and induced apoptosis. SS also induced several subpopulations of cells defined by their expression of proliferation markers and DNA strand breaks. By 72 h the rapidly proliferating cells [PCNA/Ki-67(+)/TUNEL(-)] were reduced from > 90% to about one third. Of the remaining cells, about one third were apoptotic [PCNA/Ki-67(-)/TUNEL(+)] and one third were quiescent [PCNA/Ki-67(-)/TUNEL(-)]. Another subpopulation was detected that was PCNA/Ki-67(+)/TUNEL(+), some had a dominant subdiploid peak and over half were in S or G2/M phases by DNA content. Thus, a subpopulation of apoptotic cells strongly expressed PCNA and Ki-67, suggesting that their specificity as proliferation markers may need reassessment. Similar results were obtained with the HL-60 promyelocytic cell line.

The cell cycle in breast cancer

Breast cancer is a heterogeneous disease regarding morphology, invasive behavior, metastatic capacity, hormone receptor expression and clinical outcome. For prediction of prognosis, tumor cell kinetics is an important feature, traditionally evaluated by estimation of cell growth-associated parameters such as mitotic index, S-phase fraction and expression of proliferation coupled proteins, for example proliferating cell nuclear antigen (PCNA) and Ki-67 antigen. Recent data indicate that deregulation of the cell cycle can occur at different levels in cancer and that the "deregulation pattern" can be of clinical significance. In the present overview we give a short description of approaches used for cell proliferation assessments, whereafter more recent data on cell cycle deregulation are discussed. Alterations of importance in breast cancer include overexpression of cyclins D1 and E, down-regulation of cyclin-dependent kinase inhibitors, such as p16, and inactivation of the retinoblastoma and p53 tumor suppressor proteins.

Sulindac sulfide inhibits the proliferation of colon cancer cells: diminished expression of the proliferation markers PCNA and Ki-67

We evaluated the effect of sulindac sulfide (SS), which reduces cell number and induces apoptosis in cultured colon cancer cells (CCCs), on expression of the proliferation markers PCNA and Ki-67 in HT-29 and HCT-15 CCCs; only the former express cyclooxygenases. DNA content and PCNA/Ki-67 expression were analyzed by bivariate flow cytometry. SS inhibited cell proliferation, determined by the reduced expression of PCNA and Ki-67, roughly by half at 72 h, and induced apoptosis (accounting for about two-thirds and one-third of the reduction in cell number, respectively). A similar effect of SS occurred in HT-29 and HCT-15 CCCs, and also in non-colonic cells, indicating that this rather general effect of SS on cultured cells is not dependent on inhibition of prostaglandin synthesis.

Cytological evaluation of biological prognostic markers from primary breast carcinomas

This study was undertaken to evaluate our ability to detect multiple molecular markers of prognosis and response to treatment in fine needle aspirates (FNA) from patients with primary breast carcinomas. 147 patients with operable primary breast carcinomas who had been recruited to a randomized trial of primary medical therapy (PMT) versus adjuvant chemoendocrine therapy were analysed. FNAs were taken prior to therapy and from this multiple slides were produced using cytospin cytocentrifugation and stored at -80 degrees C for subsequent immunocytochemical analysis (ICA). ICA was performed for oestrogen receptor (ER), progesterone receptor (PgR), p53, Ki67, and Bcl-2. Part of the aspirate was snap frozen and used for flow cytometric analysis of ploidy and S-phase fraction (SPF). In a subgroup of 50 patients who had surgery prior to systemic therapy, as well as FNAs, sections were also taken from paraffin-embedded blocks and stained by ICA for ER, PgR and p53 for validation. In these patients ER was additionally measured by enzyme immunoassay (EIA) from frozen tissue taken at surgery. ER, PgR, p53, Bcl-2, and Ki67 were successfully detected by ICA while ploidy and SPF were successfully measured by flow cytometry from FNA material. The percentage positive values obtained were reasonable and as follows: 74% for ER, 70% for PgR, 36% for p53, 80% for Bcl-2,68% of tumours were aneuploid and 32% diploid. Significant relationships between these measurements were observed in accordance with expectations. The concordance for ER, PgR, and p53 from FNA when compared to ICA of matching histological sections was 91.5%, 75.5%, and 75% respectively. For ER the concordance between measurement by ICA of cytological and histological samples and by EIA of frozen tissue was 82.5% and 84% respectively. These results indicate that multiple molecular markers can be adequately tested on cytological preparations from primary breast tumours. These markers can be used to determine prognosis and predict response to PMT.

Analysis of Cdc2 and Cyclin D1 Expression in Breast Cancer by Immunoblotting

Cyclins and cyclin-dependent kinases may reflect the status of cell proliferation in cancer tissues. The authors sought to determine whether cdc2 and cyclin D1 are expressed in breast cancer and are useful as prognostic factors. Accumulation of cdc2 and cyclin D1 proteins was examined in 88 cases of breast cancer using immunoblotting techniques and correlations with clinicopathological factors and prognoses were investigated. Cdc2 and cyclin D1 proteins were observed in 27.3 % and 75.0 % of breast cancers studied, respectively. The incidence of lymph node metastasis was significantly high in cdc2/cyclin D1-double positive group and low in double negative group. On the other hand, the incidence of estrogen receptor (ER) negative cases was significantly higher in the cdc2-positive/cyclin D1-negative group. Relapse-free survival times of cdc2-positive cases were significantly shorter than those of Cdc2-negative cases. The relapse-free survival times of cyclin D1-positive cases also tended to be poorer than those of cyclin D1-negative cases. Multivariate analyses revealed cdc2 as the second most significant of the prognostic variables, following lymph node status. The three-year relapse-free survival rate of cdc2/cyclin D1-double positive cases was 58.9%, whereas that of cdc2/cyclin D1-doublue negative cases was 100%. Cdc2 and cyclin D1 represent the status of cell proliferation in breast cancer, and may be useful in breast cancer assessment.