Neo-adjuvant chemotherapy for operable breast cancer induces apoptosis

Can Multi-Parametric MR Based Approach Improve the Predictive Value of Pathological and Clinical Therapeutic Response in Breast Cancer Patients?

The potential of total choline (tCho), apparent diffusion coefficient (ADC) and tumor volume, both individually and in combination of all these three parameters (multi-parametric approach), was evaluated in predicting both pathological and clinical responses in 42 patients with locally advanced breast cancer (LABC) enrolled for neoadjuvant chemotherapy (NACT). Patients were sequentially examined by conventional MRI; diffusion weighted imaging and in vivo proton MR spectroscopy at 4 time points (pre-therapy, after I, II, and III NACT) at 1.5 T. Miller Payne grading system was used for pathological assessment of response. Of the 42 patients, 24 were pathological responders (pR) while 18 were pathological non-responders (pNR). Clinical response determination classified 26 patients as responders (cR) while 16 as non-responders (cNR). tCho and ADC showed significant changes after I NACT, however, MR measured tumor volume showed reduction only after II NACT both in pR and cR. After III NACT, the sensitivity to detect responders was highest for MR volume (83.3% for pR and 96.2% for cR) while the specificity was highest for ADC (76.5% for pR and 100% for cR). Combination of all three parameters exhibited lower sensitivity (66.7%) than MR volume for pR prediction, however, a moderate improvement was seen in specificity (58.8%). For the prediction of clinical response, multi-parametric approach showed 84.6% sensitivity with 100% specificity compared to MR volume (sensitivity 96.2%; specificity 80%). Kappa statistics demonstrated substantial agreement of clinical response with MR volume (k = 0.78) and with multi-parametric approach (k = 0.80) while moderate agreement was seen for tCho (k = 0.48) and ADC (k = 0.46). The values of k for tCho, MR volume and ADC were 0.31, 0.38, and 0.18 indicating fair, moderate, and slight agreement, respectively with pathological response. Moderate agreement (k = 0.44) was observed between clinical and pathological responses. Our study demonstrated that both tCho and ADC are strong predictors of assessment of early pathological and clinical responses. Multi-parametric approach yielded 100% specificity in predicting clinical response. Following III NACT, MR volume emerged as highly suitable predictor for both clinical and pathological assessments. PCA demonstrated separate clusters of pR vs. pNR and cR vs. cNR at post-therapy while with some overlap at pre-therapy.

Apoptosis, Chemoresistance, and Breast Cancer: Insights From the MCF-7 Cell Model System

The MCF-7 cell line was derived from a patient with metastatic breast cancer in 1970. Since then it has become a prominent model system for the study of estrogen receptor-positive breast cancer. With this model as a focus, this review summarizes important studies addressing tumor necrosis factor-α as a prototypical apoptosis-inducing cytokine in MCF-7 cells. Both survival and death receptor signaling pathways are discussed in terms of their role in chemotherapy-induced apoptosis as well as in chemoresistance. Novel therapeutic approaches to the treatment of breast cancer are proposed utilizing knowledge of these signaling pathways as targets. Specifically, ceramide metabolism is proposed as a novel target for chemosensitivity, perhaps combined with selective inhibitors of Bcl-2 or PI3K/Akt/nuclear factor-κB. Suggested areas of future research include translational studies manipulating candidate survival and death signaling pathways.

Simultaneous Bilateral Breast Carcinomas: A Category with Frequent Coexpression of HER-2 and ER-α, High Ki-67 and bcl-2, and Low p53

The aim of this study was to evaluate clinicopathological characteristics and immunophenotypes of simultaneous bilateral adenocarcinomas of the breast and their axillary metastases. Immunohistochemical analysis and in situ hybridization were performed using formalin-fixed/paraffin-embedded tissues. In total, 15 primary and 9 metastatic tumors from 8 patients were evaluated. The expression of estrogen receptor-alpha (ER-α), progesterone receptor (PR), Ki 67, p53, bcl-2, and bax were evaluated by immunohistochemistry. Her2 gene amplification was evaluated by chromogenic in situ hybridization (CISH). Four patients were younger that 40 years of age (mean 47 years). Six patients had pleomorphic lobular carcinoma in 1 breast. Four of these had invasive ductal carcinoma in the contralateral breast. One patient had atypical medullary carcinoma in both breasts and 1 patient had atypical medullary carcinoma in 1 breast and pleomorphic lobular carcinoma in the other. The phenotype of the primary tumors and corresponding metastatic tumors was similar for the expression of ER-α (p=0.001), PR (p=0.03), and HER-2 (p=0.018). While strong coexpression of HER-2 and ER-α is exceptional in hereditary breast carcinoma and sporadic breast carcinoma, 6/8 (75%) patients in this study had tumors with strong coexpression of HER-2 and ER-α. P53 protein expression was found in only 2/15 (13%) primary tumors, which is in contrast to BRCA1-related hereditary bilateral breast carcinomas, which often express p53 protein. Most of the patients presented with axillary metastases and had very aggressive course. Characteristically, the tumors showed high levels of expression of ER-α and Her2 amplification, were bcl-2 positive, and had high Ki-67 fraction. However, in patients with atypical medullary carcinoma there was no expression of ER-α or amplification of Her-2.

The expression of SIAH1 is downregulated and associated with Bim and apoptosis in human breast cancer tissues and cells

Seven in absentia homolog1 (SIAH1) was reported as a tumor suppressor and played an important role in regulating cell apoptosis. However, its effects on the breast carcinogenesis remain unclear. In this study, our aims were to examine the relationship between SIAH1 and Bcl-2-interacting mediator of cell death (Bim) and to explore the effects of SIAH1 on the breast carcinogenesis. Immunohistochemical analysis in 231 cases of breast tissues showed that the expression of SIAH1 and Bim were significantly decreased in the breast carcinogenesis. Moreover, SIAH1 expression was significantly correlated with Bim. Both SIAH1 and Bim expression were significantly higher in well to moderately differentiated and in early-stage breast cancer. Reverse transcription (RT)-polymerase chain reaction (PCR) and Western blot analysis in paired breast cancer tissues and breast cell lines found that the expression of SIAH1 was lower in the breast cancer tissues and cell lines. SIAH1 inducing apoptosis of the breast cancer cells was dependent on Bim. However, SIAH1 inhibiting invasion of the breast cancer cells was independent of Bim. The increase of the function of SIAH1 to upregulate the expression of Bim may play an important role in the progression of breast cancer. Restoration of the function of SIAH1 may be a new therapeutic target of human breast cancer.

What's new in neoadjuvant therapy for breast cancer?

Neoadjuvant treatment of breast cancer is currently being used in patients with advanced disease as well as with increasing application in those that present with initially operable breast cancer. The current clinical benefits of the use of NAC include: NAC increases the possibility of the use of BCS, the safety of NAC is comparable with that of adjuvant chemotherapy, and pCR may be predictive of overall survival. Although there are still unresolved clinical questions regarding the use of neoadjuvant therapy in initially operable breast cancer, there appears to be equivalent survival to the standard of care. Future research should be aimed at tailoring treatment to individual patients using specific tumor characteristics that may predict response to different types of chemotherapy, molecular targeted therapy, and endocrine therapy.

Semi-automated imaging system to quantitate estrogen and progesterone receptor immunoreactivity in human breast cancer

A semi-automated imaging system is described to quantitate estrogen and progesterone receptor immunoreactivity in human breast cancer. The system works for any conventional method of image acquisition using microscopic slides that have been processed for immunohistochemical analysis of the estrogen receptor and progesterone receptor. Estrogen receptor and progesterone receptor immunohistochemical staining produce colorimetric differences in nuclear staining that conventionally have been interpreted manually by pathologists and expressed as percentage of positive tumoral nuclei. The estrogen receptor and progesterone receptor status of human breast cancer represent important prognostic and predictive markers of human breast cancer that dictate therapeutic decisions but their subjective interpretation result in interobserver, intraobserver and fatigue variability. Subjective measurements are traditionally limited to a determination of percentage of tumoral nuclei that show positive immunoreactivity. To address these limitations, imaging algorithms utilizing both colorimetric (RGB) as well as intensity (gray scale) determinations were used to analyze pixels of the acquired image. Image acquisition utilized either scanner or microscope with attached digital or analogue camera capable of producing images with a resolution of 20 pixels /10 mu. Areas of each image were screened and the area of interest richest in tumour cells manually selected for image processing. Images were processed initially by JPG conversion of SVS scanned virtual slides or direct JPG photomicrograph capture. Following image acquisition, images were screened for quality, enhanced and processed. The algorithm-based values for estrogen receptor and progesterone receptor percentage nuclear positivity both strongly correlated with the subjective measurements (intraclass correlation: 0.77; 95% confidence interval: 0.59, 0.95) yet exhibited no interobserver, intraobserver or fatigue variability. In addition the algorithms provided measurements of nuclear estrogen receptor and progesterone receptor staining intensity (mean, mode and median staining intensity of positive staining nuclei), parameters that subjective review could not assess. Other semi-automated image analysis systems have been used to measure estrogen receptor and progesterone receptor immunoreactivity but these either have required proprietary hardware or have been based on luminosity differences alone. By contrast our algorithms were independent of proprietary hardware and were based on not just luminosity and colour but also many other imaging features including epithelial pattern recognition and nuclear morphology. These features provide a more accurate, versatile and robust imaging analysis platform that can be fully automated in the near future. Because of all these properties, our semi-automated imaging system 'adds value' as a means of measuring these important nuclear biomarkers of human breast cancer.

Preoperative chemotherapy for women with operable breast cancer

BACKGROUND

Currently, preoperative chemotherapy is the standard of care in locally advanced breast cancer to achieve local tumour downsizing in order to make surgery possible. Since the early 1980s, the role of preoperative chemotherapy in early stage (or operable) breast cancer has been the subject of study. Potential advantages are early introduction of systemic therapy, determination of chemosensitivity, reduction of tumour volume and downstaging of surgical requirement. Concerns exist about local control after downsized surgery and the delay of local treatment in patients with tumours resistant to chemotherapy.

OBJECTIVES

To assess the effectiveness of preoperative chemotherapy in women with operable breast cancer when compared to postoperative chemotherapy.

SEARCH STRATEGY

The Specialised Register maintained by the Editorial Base of the Cochrane Breast Cancer Group was searched on 4th of August 2005.

SELECTION CRITERIA

Randomised trials comparing preoperative chemotherapy with postoperative in women with operable breast cancer.

DATA COLLECTION AND ANALYSIS

Studies were assessed for eligibility and quality, and data were extracted by two independent review authors. Hazard ratios were derived for time-to-event outcomes directly or indirectly using the methods described by Parmar. Relative risks were derived for dichotomous outcomes. Meta-analyses were performed using fixed effect model.

MAIN RESULTS

We identified 14 eligible studies which randomised a total of 5,500 women. Median follow-up ranged from 18 to 124 months. Eight studies described a satisfactory method of randomisation.Data, based on 1139 estimated deaths in 4620 women available for analysis, show equivalent overall survival rates with a HR of 0.98 (95% CI, 0.87 to 1.09; p, 0.67; no heterogeneity). Preoperative chemotherapy increases breast conservation rates, yet at the associated cost of increased loco regional recurrence rates. However, this rate was not increased as long as surgery remains part of the treatment even after complete tumour regression (HR, 1.12; 95% CI, 0.92 to 1.37; p, 0.25; no heterogeneity. Preoperative chemotherapy was associated with fewer adverse effects. Pathological complete response is associated with better survival than residual disease (HR, 0.48; 95% CI, 0.33 to 0.69; p, < 10-4).

AUTHORS' CONCLUSIONS

This review suggests safe application of preoperative chemotherapy in the treatment of women with early stage breast cancer in order to down-stage surgical requirement, to evaluate chemosensitivity and to facilitate translational research.

In vivo model for research of breast cancer biomarkers

The preoperative (neoadjuvant) setting of breast cancer treatment is an optimal in vivo model by which to allow the characterization of biomarker expression pattern with the tumor remaining in situ throughout treatment as an in vivo measure of response to particular therapy. Elucidating surrogate molecular or cellular markers of tumor response to therapy, may provide biological insight into both, the mechanism of tumor growth dynamics and drug sensitivity/resistance. Owing to the knowledge that many drugs are effective on actively proliferating cells and more intriguingly, that many anticancer agents with differing modes of action achieve cytotoxic effects by inducing apoptosis, has lead to a reappraisal of traditional views of tumor response/resistance to cytotoxic drugs in vivo. Accordingly, this review article will focus on discussing apoptosis phenomena and the p53 and bcl-2 protein as its regulators of principal impor?tance; a cell proliferation determined by the Ki-67 expression, as the major counterbalancing process to apoptosis is also considered. This paper reviews the rationale for the use of these proteins as indices of tumor response to therapy, as well as the published literature regarding their clinical relevance. So far, no firm conclusions can be made concerning their predictive utility. .

Neoadjuvant versus adjuvant systemic treatment in breast cancer: a meta-analysis

BACKGROUND

Interest in the use of preoperative systemic treatment in the management of breast cancer has increased because such neoadjuvant therapy appears to reduce the extent of local surgery required. We compared the clinical end points of patients with breast cancer treated preoperatively with systemic therapy (neoadjuvant therapy) and of those treated postoperatively with the same regimen (adjuvant therapy) in a meta-analysis of randomized trials.

METHODS

We evaluated nine randomized studies, including a total of 3946 patients with breast cancer, that compared neoadjuvant therapy with adjuvant therapy regardless of what additional surgery and/or radiation treatment was used. Fixed and random effects methods were used to combine data. Primary outcomes were death, disease progression, distant disease recurrence, and loco-regional disease recurrence. Secondary outcomes were local response and conservative local treatment. All statistical tests were two-sided.

RESULTS

We found no statistically or clinically significant difference between neoadjuvant therapy and adjuvant therapy arms associated with death (summary risk ratio [RR] = 1.00, 95% confidence interval [CI] = 0.90 to 1.12), disease progression (summary RR = 0.99, 95% CI = 0.91 to 1.07), or distant disease recurrence (summary RR = 0.94, 95% CI = 0.83 to 1.06). However, neoadjuvant therapy was statistically significantly associated with an increased risk of loco-regional disease recurrences (RR = 1.22, 95% CI = 1.04 to 1.43), compared with adjuvant therapy, especially in trials where more patients in the neoadjuvant, than the adjuvant, arm received radiation therapy without surgery (RR = 1.53, 95% CI = 1.11 to 2.10). Across trials, we observed heterogeneity in the rates of complete clinical response (range = 7%-65%; P for heterogeneity of <.001), pathologic response (range = 4%-29%; P for heterogeneity of <.001), and adoption of conservative local treatment (range = 28%-89% in neoadjuvant arms, P for heterogeneity of <.001).

CONCLUSIONS

Neoadjuvant therapy was apparently equivalent to adjuvant therapy in terms of survival and overall disease progression. Neoadjuvant therapy, compared with adjuvant therapy, was associated with a statistically significant increased risk of loco-regional recurrence when radiotherapy without surgery was adopted.

Primary chemotherapy for breast cancer: the evidence and the future

The first generation of randomised trials assessing the role of primary chemotherapy in breast cancer has failed to demonstrate the expected survival benefit. However, it has established the role of this treatment in 'downstaging' tumours of patients with locally advanced disease and, consequently, in improving breast conservation rates. Also, a number of surrogates of outcome have been identified, which will hopefully lead to earlier results in breast cancer clinical trials. Encouraging results have also been reported in trials investigating a number of novel approaches.

A novel continuous infusional 5-fluorouracil-based chemotherapy regimen compared with conventional chemotherapy in theneo-adjuvant treatment of early breast cancer: 5 year results of the TOPIC trial

BACKGROUND

To compare the efficacy of continuous infusional 5-fluorouracil (5-FU)-based chemotherapy against conventional bolus chemotherapy in the preoperative treatment of patients with large operable early breast cancer.

PATIENTS AND METHODS

Four hundred and twenty-six women with histologically proven 3 cm invasive early breast cancer were randomised to receive pre-operative infusional 5-FU 200 mg/m(2) by daily 24 h continuous infusion via a Hickman line for 18 weeks with epirubicin 60 mg/m(2) intravenous (i.v.) bolus on day 1 and cisplatin 60 mg/m(2) i.v. bolus on day 1, both repeating 3-weekly (infusional ECisF), or conventional bolus doxorubicin 60 mg/m(2) i.v. on day 1 and cyclophosphamide 600 mg/m(2) i.v. on day 1, both repeating 3-weekly (AC), both schedules for six courses. Patients subsequently had local therapy (surgery or radiotherapy or both) and tamoxifen 20 mg orally daily as appropriate.

RESULTS

The 5 year results for AC and infusional ECisF, respectively, were as follows: overall response, 75% and 77%; complete clinical remission, 31% and 34%; pathological complete remission (pathCR), 16% for both; and pathCR with residual ductal carcinoma in situ (DCIS), 25% and 24%. Mastectomy rates were 37% and 34%, respectively. Five-year overall survival was 74% for AC and 82% for infusional ECisF (hazard ratio 0.76, 95% confidence interval 0.51-1.13; P = 0.18). Both treatments were well tolerated. Grade III/IV lethargy, vomiting, alopecia and plantar-palmar erythema were significantly greater for infusional ECisF; grade III/IV leucopenia was significantly greater for AC.

CONCLUSIONS

Preoperative continuous infusional 5-FU-based chemotherapy is no more active than conventional AC for early breast cancer; with a median 5 year follow-up, the infusion-based schedule shows a non-significant trend towards improved survival.

Is there still a role for neoadjuvant therapy in breast cancer?

The role of neoadjuvant chemotherapy in locally advanced breast cancer is firmly established. There is now also an emerging role for neoadjuvant systemic therapy in the treatment of operable breast cancer. There is good evidence that the chances of breast conserving surgery can be increased with this approach and results of randomised studies indicate that survival is at least as good with neoadjuvant as with adjuvant chemotherapy. Similar clinical data are emerging with neoadjuvant endocrine therapy. For the future, there are important potential advantages in having an in vivo measure of chemosensitivity rather than blindly treating micrometastatic disease in the adjuvant setting. Clinical response to neoadjuvant treatment, and in particular complete pathological response, are predictors of subsequent outcome. Pathological involvement of axillary nodes following neoadjuvant therapy portends a poor prognosis. The potential for biological surrogate markers of response to predict for long-term outcome may allow individualisation of systemic treatment and the rapid assessment of new drugs in early breast cancer.

Preoperative/neoadjuvant medical therapy for early breast cancer

Preoperative (neoadjuvant) medical therapy has emerged over the past decade as a new approach for the treatment of early breast cancer. Results show it has high activity, but survival is no better than with conventional adjuvant treatment. The need for mastectomy is reduced but not abolished; in some studies this effect is associated with a small increase in risk of local recurrence, but without any detriment to survival. Predictive factors for improved outcome include clinical response, and especially pathological complete remissions. However, persisting pathological axillary node involvement is associated with poor outcome. Biological changes in apoptosis or proliferation pathways may prove to be more sensitive surrogate markers than clinical or pathological responses for assessing treatment outcome. The main long-term aim of preoperative medical treatment must be to establish such surrogate predictive markers. This would lead to individualised treatment for each patient, and would allow much more rapid assessment of new drugs than is currently possible with adjuvant therapy trials.

Growth arrest and cell death in the breast tumor cell in response to ionizing radiation and chemotherapeutic agents which induce DNA damage

Breast tumor cells are relatively refractory to apoptosis in response to modalities which induce DNA damage such as ionizing radiation and the topoisomerase II inhibitor, adriamycin. Various factors which may modulate the apoptotic response to DNA damage include the p53 status of the cell, levels and activity of the Bax and Bcl-2 families of proteins, activation of NF-kappa B, relative levels of insulin like growth factor and insulin-like growth factor binding proteins, activation of MAP kinases and PI3/Akt kinases, (the absence of) ceramide generation and the CD95 (APO1/Fas) signaling pathway. Prolonged growth arrest associated with replicative senescence may represent an alternative and reciprocal response to DNA-damage induced apoptosis that is p53 and/or p21waf1/cip1 dependent while delayed apoptosis may occur in p53 mutant breast tumor cells which fail to maintain the growth-arrested state. Clearly, the absence of an immediate apoptotic response to DNA damage does not eliminate other avenues leading to cell death and loss of self-renewal capacity in the breast tumor cell. Nevertheless, prolonged growth arrest (even if ultimately succeeded by apoptotic or necrotic cell death) could provide an opportunity for subpopulations of breast tumor cells to recover proliferative capacity and to develop resistance to subsequent clinical intervention.

Significance of Apoptosis and Apoptotic-Related Proteins, Bcl-2, and Bax in Primary Breast Cancer

Apoptosis and expression of apoptosis-regulating proteins, Bcl-2 and Bax, have been observed in human breast carcinomas. The authors investigated whether expression of Bcl-2 and Bax proteins and apoptotic index (AI) had significance in cases of primary breast cancer. The authors evaluated Bcl-2 and Bax immunoreactivity and AI in primary breast cancers with the ApopTag method in 91 breast cancer patients retrospectively with long-term follow-up (median 60 months). Bcl-2 expression was seen in 60 (65.9%) cases and Bax expression was observed in 59 (64.8%) cases. Increased Bcl-2 and absence or low Bax immunoreactivity were significantly associated with low AI, high tumor grade, axillary lymph node involvement, postoperative recurrence, and metastasis. Thirty-five (38.5%) samples expressed high AI, which correlated with low tumor grade, absent axillary lymph node metastasis, and low levels of Bcl-2 with Bax overexpression. In univariate analysis, the variables associated with short relapse-free survival (RFS) and overall survival (OS) were large tumor size, axillary lymph node involvement, high histologic grade, low AI, high Bcl-2 expression, and absence or low Bax expression. In multivariate analysis, only Bcl-2 expression, lymph node status, and histologic grade were of independent prognostic value with respect to RFS and OS. Because the vast majority of the patients in this study received chemotherapy, it can be concluded that these apoptotic markers were also predictive of response to chemotherapy. Immunostaining of apoptosis-related genes, Bcl-2 and Bax, together with AI, may stratify high- versus low-risk breast cancer patients.

Gene therapy for carcinoma of the breast: Pro-apoptotic gene therapy

The dysregulation of apoptosis contributes in a variety of ways to the malignant phenotype. It is increasingly recognized that the alteration of pro-apoptotic and anti-apoptotic molecules determines not only escape from mechanisms that control cell cycle and DNA damage, but also endows the cancer cells with the capacity to survive in the presence of a metabolically adverse milieu, to resist the attack of the immune system, to locally invade and survive despite a lack of tissue anchorage, and to evade the otherwise lethal insults induced by drugs and radiotherapy. A multitude of apoptosis mediators has been identified in the past decade, and the roles of several of them in breast cancer have been delineated by studying the clinical correlates of pathologically documented abnormalities. Using this information, attempts are being made to correct the fundamental anomalies at the genetic level. Fundamental to this end are the design of more efficient and selective gene transfer systems, and the employment of complex interventions that are tailored to breast cancer and that are aimed concomitantly towards different components of the redundant regulatory pathways. The combination of such genetic modifications is most likely to be effective when combined with conventional treatments, thus robustly activating several pro-apoptotic pathways.