EGFR, HER-2/neu, cyclin D1, p21 and p53 in correlation to cell proliferation and steroid hormone receptor status in ductal carcinoma in situ of the breast

The clinical and biological significance of HER2 over-expression in breast ductal carcinoma in situ: a large study from a single institution

BACKGROUND

Previous studies have reported up to 50% of ductal carcinoma in situ (DCIS), is HER2 positive, but the frequency of HER2-positive invasive breast cancer (IBC) is lower. The aim of this study is to characterise HER2 status in DCIS and assess its prognostic value.

METHODS

HER2 status was evaluated in a large series of DCIS (n = 868), including pure DCIS and DCIS associated with IBC, prepared as tissue microarrays (TMAs). HER2 status was assessed using immunohistochemistry (IHC) and chromogenic in situ hybridisation (CISH).

RESULTS

In pure DCIS, HER2 protein was over-expressed in 9% of DCIS (3+), whereas 15% were HER2 equivocal (2+). Using CISH, the final HER2 status was positive in 20%. In mixed DCIS, HER2 amplification of the DCIS component was detected in 15% with amplification in the invasive component of only 12%. HER2-positive DCIS was associated with features of aggressiveness (p < 0.0001) and more frequent local recurrence (p = 0.03). On multivariate analysis, combined HER2+/Ki67+ profile was an independent predictor of local recurrence (p = 0.006).

CONCLUSIONS

The frequency of HER2 positivity in DCIS is comparable to IBC- and HER2-positive DCIS is associated with features of poor prognosis. The majority of HER2 over-expression in DCIS is driven by gene amplification.

Intratumoral Heterogeneity in Ductal Carcinoma In Situ: Chaos and Consequence

Ductal carcinoma in situ (DCIS) is a non-invasive proliferative growth in the breast that serves as a non-obligate precursor to invasive ductal carcinoma. The widespread adoption of screening mammography has led to a steep increase in the detection of DCIS, which now comprises approximately 20% of new breast cancer diagnoses in the United States. Interestingly, the intratumoral heterogeneity (ITH) that has been observed in invasive breast cancers may have been established early in tumorigenesis, given the vast and varied ITH that has been detected in DCIS. This review will discuss the intratumoral heterogeneity of DCIS, focusing on the phenotypic and genomic heterogeneity of tumor cells, as well as the compositional heterogeneity of the tumor microenvironment. In addition, we will assess the spatial heterogeneity that is now being appreciated in these lesions, and summarize new approaches to evaluate heterogeneity of tumor and stromal cells in the context of their spatial organization. Importantly, we will discuss how a growing understanding of ITH has led to a more holistic appreciation of the complex biology of DCIS, specifically its evolution and natural history. Finally, we will consider ways in which our knowledge of DCIS ITH might be translated in the future to guide clinical care for DCIS patients.

Ductal Carcinoma in Situ Biomarkers in a Precision Medicine Era: Current and Future Molecular-Based Testing

Historically, ductal carcinoma in situ (DCIS) of the breast has been managed aggressively with surgery and radiotherapy because of a risk of progression to invasive ductal carcinoma. However, this treatment paradigm has been challenged by overtreatment concerns and evidence that suggests that DCIS can be stratified according to risk of recurrence or risk of progression to invasive disease. Traditional methods of risk stratification include histologic grade and hormone receptor status. Recent technological advancements have enabled an era of precision medicine, where DCIS can be molecularly analyzed by tools, such as next-generation DNA and RNA sequencing, to identify molecular biomarkers for risk stratification. These findings have led to the development of tools such as the Oncotype DX Breast DCIS Score, a gene expression-based assay with the potential to prevent overtreatment in low-risk disease.

Single-cell heterogeneity in ductal carcinoma in situ of breast

Heterogeneous patterns of mutations and RNA expression have been well documented in invasive cancers. However, technological challenges have limited the ability to study heterogeneity of protein expression. This is particularly true for pre-invasive lesions such as ductal carcinoma in situ of the breast. Cell-level heterogeneity in ductal carcinoma in situ was analyzed in a single 5 μm tissue section using a multiplexed immunofluorescence analysis of 11 disease-related markers (EGFR, HER2, HER4, S6, pmTOR, CD44v6, SLC7A5 and CD10, CD4, CD8 and CD20, plus pan-cytokeratin, pan-cadherin, DAPI, and Na+K+ATPase for cell segmentation). Expression was quantified at cell level using a single-cell segmentation algorithm. K-means clustering was used to determine co-expression patterns of epithelial cell markers and immune markers. We document for the first time the presence of epithelial cell heterogeneity within ducts, between ducts and between patients with ductal carcinoma in situ. There was moderate heterogeneity in a distribution of eight clusters within each duct (average Shannon index 0.76; range 0-1.61). Furthermore, within each patient, the average Shannon index across all ducts ranged from 0.33 to 1.02 (s.d. 0.09-0.38). As the distribution of clusters within ducts was uneven, the analysis of eight ducts might be sufficient to represent all the clusters ie within- and between-duct heterogeneity. The pattern of epithelial cell clustering was associated with the presence and type of immune infiltrates, indicating a complex interaction between the epithelial tumor and immune system for each patient. This analysis also provides the first evidence that simultaneous analysis of both the epithelial and immune/stromal components might be necessary to understand the complex milieu in ductal carcinoma in situ lesions.

The Differential Regulation of Human Telomerase Reverse Transcriptase and Vascular Endothelial Growth Factor May Contribute to the Clinically More Aggressive Behavior of P63-Positive Breast Carcinomas

p63, a p53 homologue, is a myoepithelial cell marker in the normal mammary gland but p63-positive neoplastic cells may be found in up to 11% of invasive breast carcinomas. This study aims to verify the relationship between p63 expression and several clinicopathological features and tumor markers of clinical significance in breast pathology including key regulators of the cell cycle, oncogenes, apoptosis-related proteins, metalloproteinases and their inhibitors. Immunohistochemistry with 27 primary antibodies was performed in 100 formalin-fixed paraffin-embedded samples of invasive ductal carcinomas. p63-positive cells were found in 16% of carcinomas. p63-positive carcinomas were poorly differentiated, hormone receptor-negative neoplasms with a high proliferation rate. p63 also correlated with advanced pathological stage, tumor size, and the expression of human telomerase reverse transcriptase (hTERT), tissue inhibitor of matrix metalloproteinase 1 (TIMP1) and vascular endothelial growth factor (VEGF). The expression of TIMP1 suggests that the anti-proteolytic stimuli may be preponderant in p63-positive carcinomas. hTERT activity is associated with nodal metastases and cellular proliferation. VEGF regulates angiogenesis, which is also a fundamental event in the process of tumor growth and metastatic dissemination. Thus, the differential regulation of hTERT and VEGF in p63-positive breast carcinomas may contribute to the clinically more aggressive behavior of these neoplasms.

Current Approaches to Diagnosis and Treatment of Ductal Carcinoma In Situ and Future Directions

The presentation and treatment of ductal carcinoma in situ (DCIS) has changed substantially over the years. While previously an incidental pathologic finding in more advanced, palpable tumors, the institution of screening mammography has repositioned this disease entity as one largely diagnosed as a non-palpable lesion, often prior to any invasive disease. As DCIS is a precursor to invasive carcinoma, evolution in the approach to treatment has followed in the footsteps of that for invasive disease, including breast conservation therapy, adjuvant radiation, and use of antihormonal therapy. Survival outcomes for DCIS are very high and more recent literature has investigated tailoring therapeutic approaches to avoid overtreatment. Two important areas of ongoing clinical debate concerning overtreatment include use of preoperative MRI and the role of adjuvant radiation. The heterogeneity of the disease makes it difficult to differentiate lesions that would benefit from more aggressive treatment from those in which overtreatment could be avoided. Clinical characteristics, such as histologic appearance, age at diagnosis, and margin status at tumor excision have been established as moderate predictors of disease recurrence, but none has provided strong enough evidence as to guide consensus decisions on adjuvant therapy. Continuing research seeks to define the genetic and molecular characteristics that can predict disease course and serve as the potential targets for novel therapeutic agents. While several markers have shown promise in differentiating tumor aggressiveness, there is still much to be discovered about the precise mechanisms of disease progression and how this can be applied clinically to optimize treatment.

MLL1 promotes cervical carcinoma cell tumorigenesis and metastasis through interaction with β-catenin

MLL protein genes encode a family of crucial transcription factors that play a key role in multiple cancer development. The functions of different MLL proteins have not been definitively studied. MLL1 is a histone methyltransferase that mediates histone H3 lysine 4, and it has been found to have aberrant expression in several tumors. However, the function of MLL1 in cervical carcinoma is little known. We used tissue analysis, cell culture experiments, and molecular profiling to investigate the mechanism of MLL1 in cervical carcinoma development. We report here that MLL1 is overexpressed in cervical carcinoma tissues and cell lines, and its overexpression is correlated with the tumor grade. Through FACScan flow cytometry assay, we found that MLL1 promotes cell proliferation by promoting the G₁/S transition through transcriptional activation of CCND1 in cervical carcinoma cells. Furthermore, we utilized co-immunoprecipitation and glutathione S-transferase pull-down assays to identify β-catenin as the transcription partner for MLL1 and demonstrated that MLL1 and β-catenin act in synergy in the transcriptional activation of CCND1 in cervical carcinoma cells. In addition, transwell assay and anchorage-independent cell growth assay also revealed that MLL1 promotes metastasis of cervical carcinoma cells through interaction with β-catenin. Our study not only demonstrated a role for MLL1 in the proliferation and metastasis of cervical carcinoma cells but also revealed the interaction of MLL1 with β-catenin to play a different role.

Oncogene-triggered suppression of DNA repair leads to DNA instability in cancer

DNA instability is an important contributor to cancer development. Previously, defects in the chromosome segregation and excessive DNA double strand breaks due to the replication or oxidative stresses were implicated in DNA instability in cancer. Here, we demonstrate that DNA instability can directly result from the oncogene-induced senescence signaling. Expression of the activated form of Her2 oncogene, NeuT, in immortalized breast epithelial cells led to downregulation of the major DNA repair factor histone H2AX and a number of other components of the HR and NHEJ double strand DNA breaks repair pathways. H2AX expression was regulated at the transcriptional level via a senescence pathway involving p21-mediated regulation of CDK and Rb1. The p21-dependent downregulation of H2AX was seen both in cell culture and the MMTV-neu mouse model of Her2-positive breast cancer. Importantly, downregulation of H2AX upon Her2/NeuT expression impaired repair of double strand DNA breaks. This impairment resulted in both increased DNA instability in the form of somatic copy number alterations, and in increased sensitivity to the chemotherapeutic drug doxorubicin. Overall, these findings indicate that the Her2/NeuT oncogene signaling directly potentiates DNA instability and increases sensitivity to DNA damaging treatments.

siRNA targeting of Trop2 suppresses the proliferation and invasion of lung adenocarcinoma H460 cells

The aim of the present study was to investigate the effect of the small interfering RNA (siRNA)-induced inhibition of the Trop2 gene on the proliferation and invasion of lung adenocarcinoma H460 cells. A recombinant adenovirus expression vector, which contained siRNA targeting open reading frames for Trop2 (rAd5-siTrop2), was transfected into lung adenocarcinoma H460 cells. Three groups were included in the study, namely the Ctrl (non-transfected control), rAd5-siCtrl (native control) and rAd5-siTrop2 (knockdown Trop2 gene) groups. The mRNA and protein expression levels of Trop2 were detected using quantitative polymerase chain reaction and western blot analysis, respectively. In addition, the expression levels of cyclin Dl and phospho-extracellular signal regulated kinase (p-ERK)-1 were detected using western blot analysis. The effects of Trop2 inhibition on the proliferation and invasion of lung adenocarcinoma H460 cells were investigated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Transwell assay. Trop2-targeted siRNA recombinant plasmids were successfully constructed. The recombinant adenovirus vector, rAd5-siTrop2, significantly downregulated the mRNA and protein expression levels of Trop2 in the lung adenocarcinoma H460 cells, with cyclin D1 and p-ERK-1 expression downregulated simultaneously. In addition, following the silencing of Trop2, the proliferation and invasion rates of the lung adenocarcinoma H460 cells were reduced. Therefore, the results indicated that Trop2 serves a key function in the proliferation and invasion of lung adenocarcinoma H460 cells in vitro.

Short hairpin RNA targeting AKT1 and PI3K/p85 suppresses the proliferation and self-renewal of lung cancer stem cells

The aim of the present study was to investigate the effect of short hairpin (sh)RNA targeting AKT1 and phosphatidylinositol 3-kinase (PI3K)/p85 on the proliferation and self-renewal of lung cancer stem cells (LCSCs). The recombinant adenovirus expression vector, which contained shRNA targeting open reading frames of AKT1 and PI3K/p85, was transfected into LCSCs. It was found that AKT1 and PI3K/p85 expression was upregulated in LCSCs compared with that in the primary lung cancer cells. Recombinant adenovirus vector rAd5-siAKT1-siPI3K/p85 significantly downregulated AKT1 and PI3K/p85 mRNA and protein expression in LCSCs. The downstream factors, proliferating cell nuclear antigen (PCNA) and cyclin D1 were also downregulated, while p53 was upregulated. Following silencing of AKT1 and PI3K/p85, cell proliferation, tumor sphere formation and tumor formation in NOD/SCID mice were also reduced. According to the present results, it was hypothesized that the PI3K/Akt signaling pathway is important in the self‑renewal and proliferation of LCSCs, and that targeting the PI3K/Akt signaling pathway decreases the rate of tumor formation in vivo.

Preliminary results of centralized HER2 testing in ductal carcinoma in situ (DCIS): NSABP B-43

NSABP B-43 is the first prospective, randomized phase III multi-institution clinical trial targeting high-risk, HER2-positive DCIS. It compares whole breast irradiation alone with WBI given concurrently with trastuzumab in women with HER2-positive DCIS treated by lumpectomy. The primary aim is to determine if trastuzumab plus radiation will reduce in-breast tumor recurrence. HER2-positive DCIS was previously estimated at >50 %, occurring primarily in ER-negative, comedo-type DCIS of high nuclear grade. There has been no documented centralized multi-institutional HER2 analysis of DCIS. NSABP B-43 provides a unique opportunity to evaluate this in a large cohort of DCIS patients. Patients undergoing lumpectomy for DCIS without evidence of an invasive component are eligible. A central review of each patient's pure DCIS lesion is carried out by immunohistochemistry analysis. If the lesion is 2+, FISH analysis is performed. Patients whose tumors are HER2 3+ or FISH-positive are randomly assigned to receive two doses of trastuzumab during WBI or WBI alone. NSABP B-43 opened 11/9/08. As of 7/31/2013, 5,861 patients have had specimens received centrally, and 5,645 of those had analyzable blocks; 1,969 (34.9 %) were HER2 positive. A total of 1,428 patients have been accrued, 1,137 (79.6 %) of whom have follow-up information. The average follow-up time for the 1,137 patients is 23.3 months. No grade 4 or 5 toxicity has been observed. In NSABP B-43 the HER2-positive rate for pure DCIS among patients undergoing breast-preserving surgery is 34.9 %, lower than the previously reported rate. No trastuzumab-related safety signals have been observed. Interest in this trial has been robust.

QM-FISH analysis of the genes involved in the G1/S checkpoint signaling pathway in triple-negative breast cancer

This study was conducted to analyze copy number alterations (CNAs) of the genes involved in the G1/S checkpoint signaling pathway of triple-negative breast cancer (TNBC) and to evaluate their clinical value in the prognosis of TNBC. Quantitative multi-gene fluorescence in situ hybridization was used to study CNAs of the genes involved in the G1/S checkpoint signaling pathway, including cyclin d1 (CCND1), c-Myc, p21, cell-cycle-checkpoint kinase 2 gene, p16, retinoblastoma (Rb1), murine double minute 2 (Mdm2) and p53, in 60 TNBC samples and 60 non-TNBC samples. In comparison with the non-TNBC samples, CNAs of the genes involved in the G1/S checkpoint signaling pathway were more frequently observed in the TNBC samples (p = 0.000). Out of a total of eight genes, six (CCND1, c-Myc, p16, Rb1, Mdm2, and p53) exhibited significantly different CNAs between the TNBC group and the non-TNBC group. Univariate survival analysis revealed that the gene amplification of c-Myc (p = 0.008), Mdm2 (p = 0.020) and the gene deletion of p21 (p = 0.004), p16 (p = 0.015), and Rb1 (p = 0.028) were the independent predictive factor of 5-year OS for patients with TNBC. Cox multivariate analysis revealed that the gene amplification of c-Myc (p = 0.026) and the gene deletion of p21 (p = 0.019) and p16 (p = 0.034) were independent prognostic factors affecting the 5-year OS for TNBC. CNAs of the genes involved in the G1/S checkpoint signaling pathway presented a higher rate of incidence in TNBC than in non-TNBC, which could indicate one of the molecular mechanisms for the specific biological characteristics of TNBC. The genes c-Myc, p21, and p16 were correlated with the prognosis of TNBC and therefore may have potential clinical application values in the prognostic prediction of TNBC.

Next-generation sequencing: a powerful tool for the discovery of molecular markers in breast ductal carcinoma in situ

Mammographic screening leads to frequent biopsies and concomitant overdiagnosis of breast cancer, particularly ductal carcinoma in situ (DCIS). Some DCIS lesions rapidly progress to invasive carcinoma, whereas others remain indolent. Because we cannot yet predict which lesions will not progress, all DCIS is regarded as malignant, and many women are overtreated. Thus, there is a pressing need for a panel of molecular markers in addition to the current clinical and pathological factors to provide prognostic information. Genomic technologies such as microarrays have made major contributions to defining subtypes of breast cancer. Next-generation sequencing (NGS) modalities offer unprecedented depth of expression analysis through revealing transcriptional boundaries, mutations, rare transcripts and alternative splice variants. NGS approaches are just beginning to be applied to DCIS. Here, the authors review the applications and challenges of NGS in discovering novel potential therapeutic targets and candidate biomarkers in the premalignant progression of breast cancer.

Ductal carcinoma in situ of the breast: current concepts and future directions

CONTEXT

In situ carcinomas of the breast constitute 15% to 30% of all newly diagnosed breast cancer cases; 80% of these in situ lesions belong to the ductal carcinoma in situ (DCIS) category. Similar to invasive breast carcinomas, DCIS is not a single disease but rather many distinct diseases with different histopathologic and molecular characteristics, a propensity to progress to invasive disease, and differential response to treatment.

OBJECTIVE

To review the classic pathologic parameters of clinical significance and the differential diagnosis of the DCIS lesions, present our new understanding of the importance of biomarkers, and discuss innovative approaches for targeted therapy in DCIS.

DATA SOURCES

Extensive review of the relevant peer-reviewed literature.

CONCLUSIONS

In DCIS, improved understanding of the underlying biologic pathways of tumor progression is expected to lead to more accurate classification and innovative targeted treatment approaches for the management of these lesions.

Clinicopathologic, mammographic, and sonographic features in 1,187 patients with pure ductal carcinoma in situ of the breast by estrogen receptor status

The clinicopathologic, mammographic, and sonographic findings in patients with pure ductal carcinoma in situ (DCIS) were assessed by estrogen receptor (ER) expression. After institutional review board approval, patients with pure DCIS evaluated from January 1996 to July 2009 with known ER status and available imaging were identified. Images were reviewed as per the ACR BI-RADS(®) lexicon (4th edition). Clinical, pathologic, and imaging characteristics were analyzed by ER status using t test, Chi square test, and Fisher's exact test. Of 1,219 patients with pure DCIS and known ER status identified, 1,187 with complete data were included. Mammography was performed in all 1,187 patients and sonography in 519 (44 %). There were 972 (82 %) patients with ER-positive and 215 (18 %) with ER-negative disease. ER-negative DCIS was more likely to be high grade (93 vs 44 %, p < 0.0001), associated with comedonecrosis (64 vs 29 %, p < 0.0001), and multifocal (23 vs 15 %, p = 0.009). On sonography, ER-negative DCIS was more likely to be visible (61 vs 46 %, p = 0.004), larger (mean size, 2.3 vs 1.6 cm, p = 0.006), and show posterior shadowing (53 vs 28 %, p = 0.006). Mastectomy was more frequently performed for ER-negative DCIS (47 vs 37 %, p = 0.008). Palpable DCIS was visible on sonography in 55 % of cases and mammography in 81 %. Compared with ER-positive palpable DCIS, ER-negative palpable DCIS was larger and more likely to be visible on sonography. Compared with ER-positive noncalcified DCIS, ER-negative noncalcified DCIS was less likely to be visible on mammography. ER-positive and ER-negative pure DCIS have different clinicopathologic and imaging characteristics. ER-negative DCIS is associated with worse prognostic factors than ER-positive DCIS. On sonography, ER-negative DCIS is more frequently visible than ER-positive DCIS, tends to be larger, and more frequently demonstrates posterior shadowing.

miR-708 acts as a tumor suppressor in human glioblastoma cells

Glioblastoma (GBM) is one of the most lethal forms of human cancer, and new clinical biomarkers and therapeutic targets are urgently required. microRNAs (miRNAs) are small, non-coding RNAs that negatively regulate gene expression at the post-transcriptional and/or translational level by binding the 3' untranslated regions (3' UTRs) of target mRNAs. The dysregulated expression of several miRNAs has been reported to modulate glioma progression. In the present study, we defined the expression and function of miR-708, which, based on real-time PCR analysis, were downregulated in GBM cells. The overexpression of miR-708 inhibited cell proliferation and invasion and induced apoptosis in the human GBM cell lines A172 and T98G. Furthermore, the overexpression of miR-708 reduced the expression of Akt1, CCND1, MMP2, EZH2, Parp-1 and Bcl2 in A172 and T98G cells. Taken together, our study suggests that miR-708 affects GBM cell proliferation and invasion, and induces apoptosis. It is suggested that miR-708 may play an important role as a tumor suppressor in GBM and it may be an attractive target for therapeutic intervention in GBM.

Antisense transcript long noncoding RNA (lncRNA) HOTAIR is transcriptionally induced by estradiol

HOTAIR (HOX antisense intergenic RNA) is a long noncoding RNA (lncRNA) that is transcribed from the antisense strand of homeobox C gene locus in chromosome 12. HOTAIR coordinates with chromatin-modifying enzymes and regulates gene silencing. It is overexpressed in various carcinomas including breast cancer. Herein, we demonstrated that HOTAIR is crucial for cell growth and viability and its knockdown induced apoptosis in breast cancer cells. We also demonstrated that HOTAIR is transcriptionally induced by estradiol (E2). Its promoter contains multiple functional estrogen response elements (EREs). Estrogen receptors (ERs) along with various ER coregulators such as histone methylases MLL1 (mixed lineage leukemia 1) and MLL3 and CREB-binding protein/p300 bind to the promoter of HOTAIR in an E2-dependent manner. Level of histone H3 lysine-4 trimethylation, histone acetylation, and RNA polymerase II recruitment is enriched at the HOTAIR promoter in the presence of E2. Knockdown of ERs and MLLs downregulated the E2-induced HOTAIR expression. Thus, similar to protein-coding gene transcription, E2-induced transcription of antisense transcript HOTAIR is coordinated via ERs and ER coregulators, and this mechanism of HOTAIR overexpression potentially contributes towards breast cancer progression.

[Does molecular biology play any role in ductal carcinoma in situ?]

The natural history of ductal carcinoma in situ (DCIS) is not fully elucidated, but it is recognized that DCIS is the true precursor of invasive carcinoma. Studies could show that DCIS is as heterogeneous as invasive ductal carcinoma, yet, they were unable to predict which DCIS will progress to invasion. Several biomarkers were also demonstrated to have a certain prognostic value. However, except for estrogen receptors and HER2, biomarkers are not yet widely used in clinical practice since their predictive value has not proven to be better than the grade and the classical classifying systems of DCIS. Identifying biomarkers for risk of invasiveness in DCIS could be of great value to help high risk patients through the management of their disease and to avoid overtreatment in low risk patients.

Progesterone receptor inhibits proliferation of human breast cancer cells via induction of MAPK phosphatase 1 (MKP-1/DUSP1)

The roles of progesterone (P(4)) and of progesterone receptor (PR) in development and pathogenesis of breast cancer remain unclear. In this study, we observed that treatment of T47D breast cancer cells with progestin antagonized effects of fetal bovine serum (FBS) to stimulate cell proliferation, whereas siRNA-mediated knockdown of endogenous PR abrogated progestin-mediated anti-proliferative effects. To begin to define mechanisms for the anti-proliferative action of P(4)/PR, we considered the role of MAPK phosphatase 1 (MKP-1/DUSP1), which catalyzes dephosphorylation and inactivation of MAPKs. Progestin treatment of T47D cells rapidly induced MKP-1 expression in a PR-dependent manner. Importantly, P(4) induction of MKP-1 was associated with reduced levels of phosphorylated ERK1/2, whereas siRNA knockdown of MKP-1 blocked progestin-mediated ERK1/2 dephosphorylation and repression of FBS-induced cell proliferation. The importance of PR in MKP-1 expression was supported by findings that MKP-1 and PR mRNA levels were significantly correlated in 30 human breast cancer cell lines. By contrast, no correlation was observed with the glucocorticoid receptor, a known regulator of MKP-1 in other cell types. ChIP and luciferase reporter assay findings suggest that PR acts in a ligand-dependent manner through binding to two progesterone response elements downstream of the MKP-1 transcription start site to up-regulate MKP-1 promoter activity. PR also interacts with two Sp1 sites just downstream of the transcription start site to increase MKP-1 expression. Collectively, these findings suggest that MKP-1 is a critical mediator of anti-proliferative and anti-inflammatory actions of PR in the breast.

A phase II neoadjuvant trial of anastrozole, fulvestrant, and gefitinib in patients with newly diagnosed estrogen receptor positive breast cancer

Endocrine therapy in patients with breast cancer can be limited by the problem of resistance. Preclinical studies suggest that complete blockade of the estrogen receptor (ER) combined with inhibition of the epidermal growth factor receptor can overcome endocrine resistance. We tested this hypothesis in a phase II neoadjuvant trial of anastrozole and fulvestrant combined with gefitinib in postmenopausal women with newly diagnosed ER-positive breast cancer. After a baseline tumor core biopsy, patients were randomized to receive anastrozole and fulvestrant or anastrozole, fulvestrant, and gefitinib (AFG) for 3 weeks. After a second biopsy at 3 weeks, all patients received AFG for 4 months and surgery was done if the tumor was operable. The primary endpoint was best clinical response by RECIST criteria and secondary endpoints were toxicity and change in biomarkers. The study closed after 15 patients were enrolled because of slow accrual. Median patient age was 67 years and median clinical tumor size was 7 cm. Four patients had metastatic disease present. Three patients withdrew before response was assessed. In the remaining 12 patients, there were two complete clinical responses (17%), three partial responses (25%), five had stable disease (41%), and two (17%) had progressive disease. Most common adverse events were rash in four patients, diarrhea in four, joint symptoms in three, and abnormal liver function tests in three. There were no grade 4 toxicities and all toxicities were reversible. At 3 weeks, cell proliferation as measured by Ki-67 was significantly reduced in the AFG group (P value = 0.01), with a parallel reduction in the expression of the Cyclin D1 (P value = 0.02). RNA microarray data showed a corresponding decrease in the expression of cell cycle genes. These results suggest that AFG was an effective neoadjuvant therapy and consistently reduced proliferation in ER-positive tumors.

Responsiveness of adjacent ductal carcinoma in situ and changes in HER2 status after neoadjuvant chemotherapy/trastuzumab treatment in early breast cancer--results from the GeparQuattro study (GBG 40)

Adjacent ductal carcinoma in situ (DCIS) is found in approximately 45% of invasive ductal carcinomas (IDC) of the breast. Pure DCIS overexpresses HER2 in approximately 45%. There is uncertainty whether adjacent DCIS impacts on the response to neoadjuvant chemotherapy and trastuzumab as well as whether HER2 expression in IDC component or adjacent DCIS changes throughout treatment. Core biopsies and surgical tissue from participants of the GeparQuattro study with HER2-positive IDC were centrally examined for the area of invasive ductal component and adjacent DCIS before and after receiving neoadjuvant anthracycline-taxane-trastuzumab containing chemotherapy. HER2 overexpression in IDC and adjacent DCIS was quantified separately by immunohistochemistry using the Ventana automated staining system. Pathological complete response (pCR) was defined as no residual invasive or non-invasive tumor tissue. Fifty-nine (37.3%) of 158 IDCs presented with adjacent DCIS at diagnosis. These tumors showed lower regression grades than pure IDC (P = 0.033). The presence of adjacent DCIS was an independent negative predictor of pCR [odds ratio 0.42 (95% CI 0.2-0.9), P = 0.027]. Adjacent DCIS area decreased from pre-treatment to surgery (r = 0.205) with 30 (50.8%) IDCs with adjacent DCIS showing complete eradication of adjacent DCIS. HER2 status of adjacent DCIS was highly correlated with HER2 status of IDC component before (r = 0.892) and after treatment (r = 0.676). Degree of HER2 overexpression of the IDC component decreased in 16 (33.3%) out of 49 patients without a pCR. These 16 IDCs showed lower RGs compared to the 33 IDCs with unchanged HER2 expression (P = 0.055). HER2-positive IDCs with adjacent DCIS is less responsive to neoadjuvant chemotherapy and trastuzumab compared to pure IDC. However, complete eradication of adjacent DCIS is frequently observed. HER2-overexpression of the invasive ductal component decreases in a subset of tumors, which showed less tumor regression.

Biological Markers in DCIS and Risk of Breast Recurrence: A Systematic Review

Understanding of the biology and clinical behavior of ductal carcinoma in situ (DCIS) is currently inadequate. The aim of this comprehensive review was to identify important molecular biological markers associated with DCIS and candidate markers associated with increased risk of ipsilateral recurrence after diagnosis of DCIS. A comprehensive systematic review was performed to identify studies published in the past 10 years that investigated biological markers in DCIS. To be included in this review, studies that investigated the rate of biological expression of markers had to report on at least 30 patients; studies that analyzed the recurrence risk associated with biomarker expression had to report on at least 50 patients. There were 6,252 patients altogether in our review. Biological markers evaluated included steroid receptors, proliferation markers, cell cycle regulation and apoptotic markers, angiogenesis-related proteins, epidermal growth factor receptor family receptors, extracellular matrix-related proteins, and COX-2. Although the studies in this review provide valuable preliminary information regarding the expression and prognostic significance of biomarkers in DCIS, common limitations of published studies (case-series, cohort, and case-control studies) were that they were limited to small patient cohorts in which the extent of surgery and use of radiotherapy or endocrine therapy varied from patient to patient, and variable methods of determining biomarker expression. These constraints made it difficult to interpret the absolute effect of expression of various biomarkers on risk of local recurrence. No prospective validation studies were identified. As the study of biomarkers are in their relative infancy in DCIS compared with invasive breast cancer, key significant prognostic and predictive markers associated with invasive breast cancer have not been adequately studied in DCIS. There is a critical need for prospective analyses of novel and other known breast cancer molecular markers in large cohorts of patient with DCIS to differentiate indolent from aggressive DCIS and better tailor the need and extent of current therapies.

Cyclin D-1 protein over-expression is not associated with gene amplification in benign and atypical apocrine lesions of the breast

Cyclin D-1 protein over-expression and/or gene amplification have been shown to be frequent events in subsets of breast carcinomas. Cyclin D-1 is generally considered as a weak oncogene, and its over-expression has been shown to occur in occasional benign breast lesions. In a previous series, we have shown that cyclin D-1 was over-expressed in subsets of apocrine metaplasia (APM) and apocrine adenosis (AA) of the breast and that such over-expression was mostly associated with a significant increase in the proliferative capacity of these lesions. We examined the mechanisms involved in cyclin D-1 over-expression in apocrine lesions. A total of 41 cases were analysed in this study. The cases were divided into: 18 cases of APM and 23 cases of AA. All cases analysed had been previously analysed by immunohistochemistry, and all showed over-expression of the cyclin D-1 protein. Fluorescence in situ hybridisation (FISH) was performed using a dual cyclin D-1 (spectrum orange)/chromosome 11 centromere (spectrum green) DNA probe. The results showed that none of the cases studied had concomitant gene amplification. These results suggest that other post-transcriptional mechanisms might be responsible for cyclin D-1 protein over-expression in benign apocrine lesions. Further studies are needed to understand the mechanisms involved in abnormal cyclin D-1 expression in these lesions.

MiRNA-451 plays a role as tumor suppressor in human glioma cells

MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression at the post-transcriptional and/or translational level by binding loosely complimentary sequences in the 3'untranslated regions (UTRs) of target mRNAs. Increased expressions of several miRNAs, specifically hsa-miR-21, have been reported to modulate glioma development. Here we report downregulation of miR-451 in A172, LN229 and U251 human glioblastoma cells. Increased expression of miR-451 by administration of miR-451 mimics oligonucleotides reversed the biology of each of the three cell lines, inhibiting cell growth, inducing G0/G1 phase arrest and increasing cell apoptosis. Further, treatment with miR-451 mimics oligonucleotides diminished the invasive capacity of these cells, as the number of cells invading through matrigel was significantly decreased. Akt1, CyclinD1, MMP-2, MMP-9 and Bcl-2 protein expression decreased, and p27 expression increased in a dose-dependent manner with miR-451 mimics oligonucleotides. Taken together, these studies reveal miR-451 impacts glioblastoma cell proliferation, invasion and apoptosis, perhaps via regulation of the PI3K/AKT signaling pathway. We propose an essential role for miR-451 as a tumor-suppressor of human glioma.

Nuclear EGFR in ductal invasive breast cancer: correlation with cyclin-D1 and prognosis

The epidermal growth factor receptor (EGFR)-family and cyclin-D1 have been extensively studied in breast cancer; however systematic studies that examine protein expression and gene status in the same cohort of patients are lacking. Also emerging evidences suggest existence of a direct EGFR-signaling pathway, which involves cellular transport of EGFR from cell membrane to the nucleus, and transcriptional regulation of the target genes. Thus, we examined the protein expression of membrane EGFR, nuclear EGFR, cyclin-D1 and the corresponding gene status in 113 breast carcinomas by immunohistochemistry and fluorescence in situ hybridization using tissue microarrays. Membrane EGFR overexpression and EGFR gene amplification were detected in 2% cases, while nuclear EGFR was detected in 40% of cases, with 12% having high nuclear EGFR staining. Nuclear EGFR correlated with tumor size (P=0.0005), lymph node metastasis (P=0.0288), Nottingham prognostic index (P=0.0011) and estrogen receptor (ER) expression (P=0.0258) but the letter correlation was observed only in premenopausal group of patients. Strong cyclin-D1 expression and cyclin-D1 gene (CCND1) amplification were found in 64 and 13% of the cases, respectively. Cyclin-D1 expression showed positive correlation with ER (P=0.0113) and inverse correlation with Nottingham prognostic index (P=0.0309) and membrane EGFR (P=0.0201). CCND1 amplification also showed inverse correlation with membrane EGFR (P=0.0420). A strong correlation between membrane EGFR expression and gene amplification (P=0.0035), as well as cyclin-D1 overexpression and gene amplification (P=0.0362), was demonstrated. On univariate analysis cyclin-D1 expression showed a correlation with longer overall survival in the premenopausal group and nuclear EGFR correlated with shorter overall survival in whole cohort as well in the premenopausal group of patients. Multivariate analysis revealed nuclear EGFR to be an independent prognostic factor and showed 3.4 times greater mortality risk for nuclear EGFR+++ patients as compared with nuclear EGFR negative patients (hazard ratio =3.402; P=0.0026).

Gene amplification in ductal carcinoma in situ of the breast

Multiple different biologically and clinically relevant genes are often amplified in invasive breast cancer, including HER2, ESR1, CCND1, and MYC. So far, little is known about their role in tumor progression. To investigate their significance for tumor invasion, we compared pure ductal carcinoma in situ (DCIS) and DCIS associated with invasive cancer with regard to the amplification of these genes. Fluorescence in situ hybridization (FISH) was performed on a tissue microarray containing samples from 130 pure DCIS and 159 DCIS associated with invasive breast cancer. Of the latter patients, we analyzed the intraductal and invasive components separately. In addition, lymph node metastases of 23 patients with invasive carcinoma were included. Amplification rates of pure DCIS and DCIS associated with invasive cancer did not differ significantly (pure DCIS vs. DCIS associated with invasive cancer: HER2 22.7 vs. 24.2%, ESR1 19.0 vs. 24.1%, CCND1 10.0 vs. 14.8%, MYC 11.8 vs. 6.5%; P > 0.05). Furthermore, we observed a high concordance of the amplification status for all genes if in situ and invasive carcinoma of individual patients were compared. This applied also to the corresponding lymph node metastases. Our results indicate no significant differences between the gene amplification status of DCIS and invasive breast cancer concerning HER2, ESR1, CCND1, and MYC. Therefore, our data suggest an early role of all analyzed gene amplifications in breast cancer development but not in the initiation of invasive tumor growth.

Significance of HER2 protein examination in ductal carcinoma in situ

BACKGROUND

HER2 expression is routinely checked in ductal carcinoma in situ, as in invasive ductal carcinoma. However, the effect of HER2 status in ductal carcinoma in situ on the development of malignancy and the significance of overexpression of HER2 are still not clear.

MATERIALS AND METHODS

We experienced 103 cases that were diagnosed as pure ductal carcinoma in situ from operative specimens in the 2-y period from 2006 to 2007. We examined their HER2 status and other markers. We added 38 cases of ductal carcinoma in situ with small invasive disease 5mm or less in diameter as subjects. We also examined how accurately HER2 status in biopsy specimens predicted the existence of an invasive component.

RESULTS

In pure ductal carcinoma in situ, tumors that were comedo type, high grade, or ER negative showed a high frequency of HER2 overexpression. In cases with small invasion, HER2 expression was higher than that in pure ductal carcinoma in situ. Among cases that were diagnosed as ductal carcinoma in situ by biopsy, 28% had invasive disease in operative specimens. In tumors that were palpable, large, or expressed HER2 3+ in biopsy samples, invasive disease was frequently observed in operative specimens.

CONCLUSIONS

Overexpression of HER2 in ductal carcinoma in situ might not always be necessary for progression to invasive ductal carcinoma. To clarify the significance of HER2 examination in DCIS, further investigations of the potential for invasive ductal carcinoma and the prognosis are still needed.

Alterations of the cell cycle regulators cyclin D1, cyclin A, p27, p21, p16, and pRb in apocrine metaplasia of the breast

G1/S transition defects have been a proposed requirement for tumor development. Apocrine metaplasia (APM) in the breast has been held as a sign of benignity. Yet, a number of studies have reported the presence of molecular abnormalities in some forms of APM suggesting a possible oncogenic potential for some of these lesions. We currently investigate the role of some of the cell cycle proteins, previously reported to be de-regulated in breast cancer, in an attempt to assess their significance in APM. Using immunohistochemistry, the expression of cyclin D1, cyclin A, p27, p21, p16, pRb and Ki-67 was examined in 93 cases of APM. The cases were divided into nonpapillary (NAPM) (30 cases) and papillary metaplasia (PAPM) (63 cases). PAPM was further subdivided into simple papillary (SPAPM) (29 cases), complex papillary (28 cases) and highly complex papillary (six cases). For statistical analysis, the last two groups were merged together (CPAPM). The results showed that increased histological complexity was associated with significant increase of proliferative capacity and alterations of the cell cycle control. The median Ki-67 index was 1.5% in SPAPM and 4.8% in the CPAPM. Also, alterations of the cell cycle regulators were significantly higher in the CPAPM than in the SPAPM. NAPM was generally similar to normal breast epithelium. Apocrine cells were negative for p16 while pRb was expressed in all cases. These findings suggest that in complex forms of APM, there is a considerable degree of cellular unrest. This may contribute to increased susceptibility to carcinogenesis.

Precancerous lesions of the breast

The management of precancerous lesions of the breast has become a considerable clinical problem in the past 20 years, mostly as a consequence of increased detection due to the introduction of mammographic screening. It is not possible to identify with absolute certainty which of these lesions will progress to invasive carcinoma, and tailoring the treatment according to each individual case remains a challenge. There is a particular dilemma for surgeons, who must balance the risk of resecting too much and causing unnecessary cosmetic damage, or resecting too little and leaving an increased risk of recurrence. Further knowledge in the field of predictive and prognostic factors together with the development of gene-profiling techniques will, hopefully, provide answers to these questions. Among precancerous lesions of the breast, particular attention should be paid to ductal carcinoma in situ or intraductal carcinoma, appropriate treatment of which is crucial to prevent invasive breast cancer. Nearly all possible combinations of surgery, radiotherapy and medical treatments (anti-estrogens) have been tested in different clinical trials, but the situation is far from satisfactory. We believe that an important contribution can come from oncoplastic surgery, which is the application of plastic and reconstructive surgical techniques to ensure both radical excision of the disease and acceptable cosmetic outcomes.

The epidermal growth factor receptor family in breast cancer

THE HUMAN EPIDERMAL GROWTH FACTOR RECEPTOR (HER) FAMILY COMPRISES FOUR HOMOLOGOUS MEMBERS: EGFR, HER-2, HER-3, and HER-4. The activation of these receptors triggers a complex series of signal transduction pathways which affect pivotal tumorigenic processes. The deregulation of HER signaling is seen in several human malignancies. HER-2 is now recognized as a key oncogene in breast cancer pathogenesis. Assessment of HER-2 status is of central importance in the prognosis of breast cancer patients. In the light of clinical data suggesting that HER-2 can also be useful as a predictive marker both for trastuzumab and chemotherapy, standardized determination of the HER-2 status in tumors has become more important. Moreover, current data provide evidence for the significance of HER-3 and HER-4 alterations in breast carcinogenesis. Because of the complex interactions among the HER receptors, it is likely that the effect on cell proliferation and tumor growth depends on receptor trans-signaling and thus, the evaluation of the combined expression pattern of all family members is of particular interest. This review presents the current evidence highlighting the role of the family as a whole panel and an update on the role of HER-3 and HER-4 receptors in breast cancer. Moreover, we provide updated data regarding the prognostic value of HER family members giving emphasis to novel methods for the determination of their status, such as real-time polymerase chain reaction. In addition, we review recent therapeutic approaches aimed at targeting the HER family in breast cancer patients.

Progesterone receptor inhibits aromatase and inflammatory response pathways in breast cancer cells via ligand-dependent and ligand-independent mechanisms

Aromatase (product of CYP19 gene), the critical enzyme in estrogen biosynthesis, is up-regulated in 70% of all breast cancers and is highly correlated with cyclooxygenase 2 (COX-2), the rate-determining enzyme in prostanoid biosynthesis. Expression of COX-2 also is correlated with the oncogene HER-2/neu. The efficacy of current endocrine therapies for breast cancer is predicted only if the tumor contains significant amounts of estrogen receptor. Because the progesterone receptor (PR) is an estrogen-induced target gene, it has been suggested that its presence may serve as an indicator of estrogen receptor functional capacity and the differentiation state of the tumor. In the present study, we tested the hypothesis that PR serves a crucial protective role by antagonizing inflammatory response pathways in the breast. We observed that progesterone antagonized the stimulatory effects of cAMP and IL-1beta on aromatase, COX-2, and HER-2/neu expression in T47D breast cancer cells. These actions of progesterone were associated with increased expression of the nuclear factor-kappaB inhibitor, IkappaBalpha. In 28 breast cancer cell lines, IkappaBalpha expression was positively correlated with PR mRNA levels; overexpression of a phosphorylation-defective mutant of IkappaBalpha inhibited expression of aromatase, COX-2, and HER-2/neu. Moreover, in breast cancer cell lines cultured in the absence of progesterone, up-regulation of endogenous PR caused decreased expression of aromatase, COX-2, and HER-2/neu expression, whereas down-regulation of endogenous PR resulted in a marked induction of aromatase and HER-2/neu mRNA. Collectively, these findings suggest that PR plays an important antiinflammatory role in breast cancer cells via ligand-dependent and ligand-independent mechanisms.

COX-2 and PPARgamma expression are potential markers of recurrence risk in mammary duct carcinoma in-situ

BACKGROUND

In women with duct carcinoma in-situ (DCIS) receiving breast conservation therapy (BCT), in-breast recurrences are seen in approximately 10%, but cannot be accurately predicted using clinical and histological criteria. We performed a case-control study to identify protein markers of local recurrence risk in DCIS.

METHODS

Women treated for DCIS with BCT, who later developed in-breast recurrence (cases) were matched by age and year of treatment to women who remained free of recurrence (controls).

RESULTS

A total of 69 women were included in the study, 31 cases and 38 controls. Immunohistochemical evaluation of DCIS tissue arrays was performed for estrogen receptor, progesterone receptor, HER-2/neu, cyclin D1, p53, p21, cycloxygenase-2 (COX-2) and peroxisome proliferator activated receptor gamma (PPARgamma). Two markers were significantly different between cases and controls on univariate analysis: strong COX-2 expression was associated with increased risk of recurrence, with 67% vs. 24% positivity in cases and controls p = 0.006; and nuclear expression of PPARgamma was associated with protection from recurrence with 4% vs. 27% positivity in cases and controls, p = 0.024. In a multivariate model which included size, grade, COX-2 and PPARgamma positivity, we found COX-2 positivity to be a strong independent risk factor for recurrence (OR 7.90, 95% CI 1.72-36.23)., whereas size and grade were of borderline significance. PPARgamma expression continued to demonstrate a protective trend, (OR 0.14, 95% CI 0.06-1.84).

CONCLUSION

Our findings suggest that COX-2 and PPARgamma should be investigated further as biologic markers to predict DCIS recurrence, particularly since they are also potential therapeutic targets.

Trastuzumab not for ductal carcinoma in situ?

Ductal carcinoma in situ (DCIS) is a preinvasive breast lesion accounting for approximately 30% of all newly detected breast cancers in the US. DCIS has been separated into two groups by architecture (comedo versus noncomedo) and nuclear grade. The expression of biological markers in DCIS, however, would reflect the true biologic potential of the lesion. Patients with estrogen receptor (ER)-negative, human epidermal growth factor-2 (HER-2)-positive DCIS pose a treatment challenge. They are not candidates for tamoxifen; trastuzumab has an undetermined role in DCIS. In this report, we present a case of a 45-year-old woman diagnosed with invasive breast cancer and ER-negative/HER-2-positive DCIS who developed recurrence and progression of DCIS as manifested by a new palpable mass while receiving trastuzumab as part of adjuvant treatment for invasive breast cancer. The potential clinical implications are discussed.

Molecular restoration of archived transcriptional profiles by complementary-template reverse-transcription (CT-RT)

Gene expression profiling of formalin-fixed and paraffin-embedded (FFPE) specimens, banked from completed clinical trials and routine clinical care, has the potential to yield valuable information implicating and linking genes with clinical parameters. In order to prepare high-quality cDNA from highly fragmented FFPE-RNA, previously precluded from high-throughput analyses, we have designed a novel strategy based on the nucleic acid restoration of incomplete cDNA sequences prior to T7 in vitro transcription (IVT) amplification. We describe this strategy as complementary-template reverse-transcription (CT-RT) because short single-stranded T7-oligo-dT₂₄-VN-DNA sequences, obtained from FFPE-RNA, are used as primers for the RT of complementary RNA templates contained in a sense-RNA library. We validated our assay by determining the correlation between expression profiles of a matched 10-year-old frozen and FFPE breast cancer sample. We show that T7 IVT-amplification of cDNA transcripts restored by CT-RT is a specific and reliable process that allows recovery of transcriptional features undetectable by direct T7 IVT-amplification of FFPE-RNA. Furthermore, CT-RT restored 35–41% of the transcripts from archived breast and cervical specimens when compared to matched frozen tissue; and profiles included tissue-specific transcripts. Our results indicate that CT-RT allows microarray profiling of severely degraded RNA that could not be analyzed by previous methods.

Precursors and preinvasive lesions of the breast: the role of molecular prognostic markers in the diagnostic and therapeutic dilemma

Precursors and preinvasive lesions of the breast include atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS), and lobular neoplasia (LN). There is a significant debate regarding the classification, diagnosis, prognosis and management of these lesions. This review article describes the current theories regarding the pathogenesis and molecular evolution of these lesions. It reviews the implication of a variety of molecules in the continuum of breast lesions: estrogen receptors (ER-alpha and ER-beta), c-erb-B2 (Her2/neu), p53, Ki-67, bcl-2, E-cadherin, transforming growth factor-beta (TGF-beta), p27 (Kip1), p16 (INK4a), p21 (Waf1), vascular endothelial growth factor (VEGF). With respect to the aforementioned molecules, this article reviews their pathophysiological importance, and puts the stress on whether they confer additional risk for invasive breast cancer or not. This knowledge has the potential to be of importance in the therapeutic decisions presenting in the common clinical practice.

The expression of FHIT, PCNA and EGFR in benign and malignant breast lesions

Immunohistochemical staining for FHIT and PCNA proteins was carried out in 451 breast lesions showing nonproliferative benign breast disease (BBD) (n=263), proliferative BBD without atypia (n=128), proliferative BBD with atypia (n=11), carcinoma in situ (n=15) or invasive carcinoma (n=34) and for EGFR protein in a subset of 71 of these cases. FHIT underexpression was not detected in nonproliferative lesions, but occurred in 2% of proliferative BBD without atypia, 10% proliferative BBD with atypia, 27% of carcinoma in situ and 41% of invasive carcinoma, which suggests that it could be useful in assessing those carcinoma in situ lesions (ductal, DCIS and lobular, LCIS) that are more likely to progress to malignancy. Preliminary microarray comparisons on DCIS and invasive carcinoma samples dissected from formalin-fixed paraffin sections showed a consistent downregulation of two previously identified FHIT-related genes, caspase 1 and BRCA1 in lesions underexpressing FHIT.

Role of the progesterone receptor (PR) in the regulation of inflammatory response pathways and aromatase in the breast

There is convincing evidence to suggest that estrogen and inflammatory mediators play important roles in growth and progression of breast cancer. Moreover, local conversion of androgens to estrogens by aromatase (product of CYP19 gene) occurs in 70% of all breast cancers. The actions of aromatase in both the breast tumor and in surrounding adipose stromal and endothelial cells can result in high local levels of estrogen production that stimulate tumor growth. The efficacy of current endocrine therapies is predicted only if the tumor contains significant amounts of ER. Presence of PR in the tumor also is an important predictor of tumor aggressiveness and responsiveness to endocrine therapy. Immunoreactivity for aromatase in human breast tumors is highly correlated with that for cyclooxygenase 2 (COX-2), the rate-determining enzyme in prostanoid biosynthesis. COX-2 expression also is correlated with expression of HER-2/neu, an oncogene expressed in >30% of breast tumors. In this manuscript, we will review findings to suggest that induction of COX-2 by inflammatory cytokines acting through NF-kappaB contributes to the increase in CYP19 expression and breast cancer progression, and that PR plays a dominant protective role in breast cancer cells by antagonizing NF-kappaB activation of COX-2.

A phase II trial of EMD72000 (matuzumab), a humanized anti-EGFR monoclonal antibody, in patients with platinum-resistant ovarian and primary peritoneal malignancies

OBJECTIVE

The primary objective of this study was to determine the rate of response to matuzumab in patients with recurrent, EGFR-positive ovarian, or primary peritoneal cancer. Secondary end points included safety and tolerability, time to tumor progression, duration of response, and overall survival.

METHODS

A multi-institutional single arm phase II trial.

RESULTS

Of 75 women screened for the study, 37 were enrolled and treated. Median age of the treated patient population was 58 years, and most patients had more than four prior lines of chemotherapy. Therapy was well tolerated, the most common toxicities being a constellation of skin toxicities, including rash, acne, dry skin, and paronychia, as well as headache, fatigue, and diarrhea. Serious adverse events were very rare but included a single episode of pancreatitis that may have been drug related. All patients completed therapy, receiving 1 to 30 infusions of matuzumab. There were no formal responses (RR=0%, 95% CI: 0-9.5%), although 7 patients (21%) were on therapy for more than 3 months with stable disease.

CONCLUSIONS

Matuzumab at the dose and schedule selected is well tolerated. In this population of very heavily pretreated patients with epithelial ovarian and primary peritoneal malignancies, there was no evidence of significant clinical activity when matuzumab was administered as monotherapy.

Prognostische Faktoren beim duktalen Carcinoma in situ

Ductal carcinoma in situ (DCIS) is a heterogeneous disease that progresses to invasive cancer in 30-50% of the patients. Its natural history is poorly defined so that we are unable to identify cases of DCIS that do not progress to invasive carcinoma during an individual's lifetime. However, pathologic features of DCIS are nowadays the basis for the estimation of the prognosis and planning of therapy. Exclusion of microinvasion, characterization of nuclear grade, architecture, size and distribution of the DCIS, presence or absence of comedonecrosis as well as the assessment of surgical margins are relevant factors for local treatment. The determination of steroid hormone receptor status is indicated in patients considering tamoxifen therapy after breast conservation. It is advisable to evaluate the features according to internationally accepted guidelines with proven prognostic relevance and reproducibility. Nevertheless, better prognostic factors are needed to adapt the management of this increasingly diagnosed disease to the individual patient.

The receptor expression pattern in ductal carcinoma in situ predicts recurrence

BACKGROUND

The treatment of ductal carcinoma in situ (DCIS) is based on size and pathologic morphology. We hypothesized that as with invasive breast cancer, receptor expression in DCIS is important for predicting recurrence.

METHODS

Retrospective review from 1990 through 2002 identified 94 DCIS patients who had documented estrogen receptor (ER), progesterone receptor (PR), p53, Her-2/neu (HER), tumor characteristics, type of surgery, use of radiation or tamoxifen, and site of recurrence.

RESULTS

Median age and tumor size was 57.5 years and 2.0 cm, respectively. Median follow-up was 4 years. Overall recurrence rate was 6%. The ER-positive/PR-negative/HER-positive receptor pattern represented 50% (3 of 6) of total recurrences (P = .01). The length of disease-free-survival in the ER-positive/PR-negative/HER-positive receptor pattern was significantly shorter than in the rest of the patients (P = .0011).

COMMENTS

Receptor expression may be important in DCIS for predicting recurrence. HER positivity, even with ER positivity, is significantly associated with a higher risk of recurrence.

Expression of HER2 and the coamplified genes GRB7 and MLN64 in human breast cancer: quantitative real-time reverse transcription-PCR as a diagnostic alternative to immunohistochemistry and fluorescence in situ hybridization

PURPOSE

Accurate testing of HER2 is centrally important for breast cancer therapy and prognosis. Immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) are current standard testing methods. As a potential alternative for assessment of HER2, we explored quantitative real-time reverse transcription-PCR (RT-PCR), a fast and inexpensive method yielding quantitative results insensitive to interobserver variability and amenable to standardized scoring.

EXPERIMENTAL DESIGN

We assessed HER2 status at the DNA, mRNA, and protein levels with FISH, quantitative RT-PCR, and IHC in 136 tumor samples from 85 breast cancer patients. Expression of GRB7, MLN64, and p21, genes coregulated with HER2, was also quantified with quantitative RT-PCR and correlated with the overall survival (OS) and disease-free survival (DFS) individually and in combination with HER2.

RESULTS

Twenty-nine percent and 19% of the patients scored HER2 positive with IHC and quantitative RT-PCR, respectively. In 18 of 19 cases, HER2 statuses in tumors and lymph node metastases were identical. HER2 status significantly correlated with DFS when determined by IHC (P < 0.01), quantitative RT-PCR (P < 0.003), but not with FISH (P = 0.09). The combination of HER2 with MLN64, but not with GRB7 or p21, enhanced the prognostic power for the DFS (P < 0.00005) and OS (P < 0.0008).

CONCLUSIONS

Quantitative RT-PCR seems to be clinically as useful in the assessment of HER2 status as IHC and FISH, yielding comparable correlations of HER2 status with the OS and DFS. Thus, quantitative RT-PCR analysis of HER2 or HER2 plus MLN64 is a promising complement or alternative to current methods for HER2 testing, particularly in laboratories lacking FISH or IHC technology.

Impact of concurrent proliferative high-risk lesions on the risk of ipsilateral breast carcinoma recurrence and contralateral breast carcinoma development in patients with ductal carcinoma in situ treated with breast-conserving therapy

BACKGROUND

The purpose of the study was to determine the risk of ipsilateral breast carcinoma recurrence (IBCR) and contralateral breast carcinoma (CBC) development in patients with a concurrent diagnosis of ductal carcinoma in situ (DCIS) with atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), or lobular carcinoma in situ (LCIS).

METHODS

Records of all 307 patients with DCIS treated with breast-conserving treatment (BCT) from 1968 to 1998 were analyzed. Initial pathology reports and all slides available were re-reviewed for evidence of ADH, ALH, or LCIS. Actuarial local recurrence rates were calculated.

RESULTS

Fifty-five cases of DCIS were associated with ADH, 11 with ALH or LCIS, and 14 with both ADH and ALH or LCIS. Overall, IBCR occurred in 14% and no significant difference in the IBCR rate was identified for patients with proliferative lesions compared with patients without these lesions (P = 0.38). Development of CBC in patients with concurrent DCIS and ADH was 4.4 times (95% confidence interval [CI], 1.44-13.63) that in patients with DCIS alone (P < 0.01). The 15-year cumulative rate of CBC development was 22.7% in patients with ALH or LCIS compared with 6.5% in patients without these lesions (P = 0.30) and 19% in patients with ADH compared with 4.1% in patients with DCIS alone (P < 0.01).

CONCLUSION

The risk of CBC development is higher with concurrent ADH than in patients with DCIS alone, and these patients may therefore be appropriate candidates for additional chemoprevention strategies. Concurrent ADH, ALH, or LCIS with DCIS is not a contraindication to BCT.

Cooperative interactions of HER-2 and HPV-16 oncoproteins in the malignant transformation of human mammary epithelial cells

To better understand the mechanisms of transformation by the oncogene HER-2, we transduced the human mammary epithelial (HME) cell line MCF-10A with HER-2 and developed a cell line that appeared to moderately overexpress HER-2. These MCF-10HER-2 cells were unable to grow in the absence of epidermal growth factor (EGF). However, coexpression of HER-2 with the HPV-16 oncoproteins E6 and E7 resulted in EGF-independent cells that expressed very high levels of constitutively activated HER-2. Interestingly, coexpression of E7 with HER-2 resulted in cells that were EGF-independent for growth but did not express HER-2 to high levels, and coexpression of E6 with HER-2 resulted in cells expressing higher levels of HER-2, which were still dependent on EGF for growth and survival. The MCF-10HER-2E7 and HER-2/E6E7 cells exhibited constitutive activation of a form of epidermal growth factor receptor (EGFR) that had a faster electrophoretic mobility than EGFR activated by exogenous growth factors. Exposure of cells with EGFR activation to ZD1839 (Iressa), at concentrations specific for EGFR, had little or no influence on proliferation of cells with amplified HER-2 but little or no EGFR. These results indicate that HER-2, E6, and E7 cooperate with endogenous EGFR to yield fully transformed cells.

Angiogenic potential of ductal carcinoma in situ (DCIS) of human breast

AIMS

Comedo carcinoma is generally regarded as the subtype of ductal carcinoma in situ (DCIS) most likely to progress to invasive carcinoma. Increased angiogenesis could be associated with an enhanced risk of progression and might therefore be a marker of poor prognosis, as can be demonstrated for invasive breast tumours. Therefore, the present study investigates the correlations between the expression of oncoproteins (HER2, HER1/EGFR), angiogenic growth factors (VEGF and PD-ECGF/TP) and microvessel density (MVD) in DCIS.

METHODS AND RESULTS

Forty-six breast cancer specimens of DCIS were tested immunohistochemically for the expression of angiogenic factors and oncoproteins. Different vascular distribution patterns of DCIS were examined semiquantitatively. Our results showed a significantly inverse correlation between HER1/EGFR and comedo-type DCIS (P = 0.048), but HER1/EGFR expression seemed to be independent of HER2 overexpression. VEGF expression was significantly associated with endoglin expression (P = 0.031) and the cuffing phenomenon (P = 0.017).

CONCLUSIONS

The significantly inverse correlation between HER1/EGFR and comedo-type DCIS and the observation that VEGF and the other angiogenic factors tested are independent of HER2 overexpression, suggest that progression of comedo-type DCIS and angiogenesis in breast carcinoma are not regulated via the HER1/EGFR or HER2 pathway.

Validation of transgenic models of breast cancer: ductal carcinoma in situ (DCIS) and Brca1-mutation-related breast cancer

Available mouse models of ductal carcinoma in situ (DCIS) and BRCA1-mutation-related breast cancer are reviewed. The best validated mouse models of human DCIS are the conditional estrogen receptor α in mammary tissue (CERM) model initiated by deregulated estrogen receptor α and the serial explant mouse model initiated by p53 deficiency. At present the most useful and best validated mouse model of BRCA1-mutation-related breast cancer uses the cre-lox system to make a conditional Brca1 deletion targeted to mammary epithelial cells. The major shortcoming of the non-conditional Brca1 models is the high incidence of non-mammary tumor development. The use of mammary gland transplants or explants from these mice into nude hosts is one approach that could be used to circumvent this deficiency. Development and validation of a Brca1-mutation-related mouse model of basal cell breast cancer is an important next step.

Absence of HER4 expression predicts recurrence of ductal carcinoma in situ of the breast

The type 1 tyrosine kinase receptor HER2 (c-erbB2/neu) is associated with resistance to hormone therapy and poor survival in invasive breast cancer, whereas HER4 expression is associated with endocrine responsiveness. Patterns of tyrosine kinase receptor coexpression may aid prediction of recurrence risk after surgery for ductal carcinoma in situ (DCIS). Women who had undergone surgery for pure DCIS were studied. Out of 129 primary tumors, 39 had recurred and 90 had not recurred after 5 years of follow-up. Primary tumors were compared for HER2, HER3, and HER4, estrogen receptor, and Ki67 by immunohistochemistry. HER2 was expressed in 58%, HER3 in 49%, and HER4 in 63% of nonrecurrent DCIS, compared with HER2 expression in 82% (P = 0.008), HER3 expression in 71% (P = 0.04), and HER4 expression in 36% (P = 0.004) in DCIS that subsequently recurred. Dually expressing HER2/4 DCIS was more likely to be estrogen receptor positive than HER2-only-expressing DCIS (73% versus 53%; P = 0.05). HER2 expression was associated with a higher percentage and HER4 expression a significantly lower percentage of proliferating DCIS cells (median, 13.8% versus 8.4%; P = 0.001). Coexpression of HER2 with HER4 was associated with reduced recurrence compared with HER2-only positive DCIS (P = 0.003). This association remained significant when analyzing only high nuclear-grade DCIS (P = 0.015). Low nuclear grade, low proliferation rate and presence of HER4 expression were independent predictors of nonrecurrence. Potentially, HER4 expression may identify women who could avoid radiotherapy after breast-conserving surgery for DCIS.