Gene Expression-Based Prediction of Neoadjuvant Chemotherapy Response in Early Breast Cancer: Results of the Prospective Multicenter EXPRESSION Trial.

PURPOSE: Expression-based classifiers to predict pathologic complete response (pCR) after neoadjuvant chemotherapy (NACT) are not routinely used in the clinic. We aimed to build and validate a classifier for pCR after NACT. PATIENTS AND METHODS: We performed a prospective multicenter study (EXPRESSION) including 114 patients treated with anthracycline/taxane-based NACT. Pretreatment core needle biopsies from 91 patients were used for gene expression analysis and classifier construction, followed by validation in five external cohorts (n = 619). RESULTS: A 20-gene classifier established in the EXPRESSION cohort using a Youden index-based cut-off point predicted pCR in the validation cohorts with an accuracy, AUC, negative predictive value (NPV), positive predictive value, sensitivity, and specificity of 0.811, 0.768, 0.829, 0.587, 0.216, and 0.962, respectively. Alternatively, aiming for a high NPV by defining the cut-off point for classification based on the complete responder with the lowest predicted probability of pCR in the EXPRESSION cohort led to an NPV of 0.960 upon external validation. With this extreme-low cut-off point, a recommendation to not treat with anthracycline/taxane-based NACT would be possible for 121 of 619 unselected patients (19.5%) and 112 of 322 patients with luminal breast cancer (34.8%). The analysis of the molecular subtypes showed that the identification of patients who do not achieve a pCR by the 20-gene classifier was particularly relevant in luminal breast cancer. CONCLUSIONS: The novel 20-gene classifier reliably identifies patients who do not achieve a pCR in about one third of luminal breast cancers in both the EXPRESSION and combined validation cohorts.

Pelvic Lymphadenectomy in Vulvar Cancer - Does it make sense?

Since the publication of the updated German guideline in 2015, the recommendations for performing pelvic lymphadenectomy (LAE) in patients with vulvar cancer (VSCC) have changed considerably. The guideline recommends surgical lymph node staging in all patients with a higher risk of pelvic lymph node involvement. However, the current data do not allow the population at risk to be clearly defined, therefore, the indication for pelvic lymphadenectomy is still not clear. There are currently two published German patient populations who had pelvic LAE which can be used to investigate both the prognostic effect of histologically verified pelvic lymph node metastasis and the relation between inguinal and pelvic lymph node involvement. A total of 1618 patients with primary FIGO stage ≥ IB VSCC were included in the multicenter AGO CaRE-1 study (1998 - 2008), 70 of whom underwent pelvic LAE. During a retrospective single-center evaluation carried out at the University Medical Center Hamburg-Eppendorf (UKE), a total of 514 patients with primary VSCC treated between 1996 - 2018 were evaluated, 21 of whom underwent pelvic LAE. In both cohorts, around 80% of the patients who underwent pelvic LAE were inguinally node-positive, with a median number of three affected groin lymph nodes. There were no cases of pelvic lymph node metastasis without inguinal lymph node metastasis in either of the two cohorts. Between 33 - 35% of the inguinal node-positive patients also had pelvic lymph node metastasis; the median number of affected groin lymph nodes in these patients was high (> 4), and the maximum median diameter of the largest inguinal metastasis was > 40 mm in both cohorts. Pelvic lymph node staging and pelvic radiotherapy is therefore probably not necessary for the majority of node-positive patients with VSCC, as the relevant risk of pelvic lymph node involvement was primarily found in node-positive patients with high-grade disease. More, ideally prospective data collections are necessary to validate the relation between inguinal and pelvic lymph node involvement.

Predicting the course of disease in recurrent vulvar cancer - A subset analysis of the AGO-CaRE-1 study.

OBJECTIVE: In vulvar cancer (VSCC), the course of disease with regard to localization of recurrence and relation of different recurrence sites is poorly described. METHODS: The AGO CaRE-1 study is a retrospective survey of treatment patterns and prognostic factors in vulvar cancer. Patients (pts) with primary VSCC, FIGO stage ≥1B treated in Germany from 1998 to 2008 were included in a centralized database (n = 1618). In the current subgroup analysis, different sites of primary recurrence and their impact on disease course and survival were analyzed using multistate and competing risks methods. RESULTS: 1249 pts with surgical groin staging and known lymph-node status (35.8% N+) were included in the analysis. 360 pts (28.8%) developed disease recurrence; thereof 193 (53.6%) at the vulva only, with a cumulative incidence of 12.6% after 2 years. Generally, prognosis after disease depended on recurrence site: Hazard ratios (HRs) (95% confidence interval) to die for pts with compared to without recurrence at the same time: vulvar only: 5.9 (4.3-8.2); groins only: 6.0 (3.0-10.2); vulvar and groins: 14.1 (7.6-26.4); pelvic/distant: 21.2 (15.3-29.4). Fifty-eight (30.1%) pts with local recurrence developed second recurrence. 2-year mortality after any recurrence was 56.3%. After vulvar recurrence pts had a 2-year and 5-year overall survival rate of 82.2% and 66.9%. CONCLUSIONS: Prognosis after recurrence is highly depending on recurrence site. Pts with isolated vulvar recurrence have an impaired prognosis as many affected pts develop second recurrences.

Predictive factors for lymph node metastases in vulvar cancer. An analysis of the AGO-CaRE-1 multicenter study.

BACKGROUND: Lymph node (LN) metastasis is the most important prognostic factor in primary vulvar cancer. Assessing risk factors for the incidence and extent of LN metastases may help to select the optimal treatment strategy for each individual patient. METHODS: In a subgroup analysis of the large multicenter AGO-CaRE-1 study we included all patients treated with radical groin dissection. Univariate and multivariate regression analyses were performed in order to detect factors associated with the prevalence and extent of nodal involvement. RESULTS: In total, 1162 patients were analyzed. Univariate analyses detected age, ECOG as well as multiple tumor characteristics such as FIGO stage, grading, depth of invasion, tumor diameter, and (lymph)vascular space invasion to be related with the prevalence of LN metastases. Interestingly, only tumor stage, tumor diameter and depth of infiltration were found to be significantly associated with the number of LN metastases. In multivariate analysis, age (OR 1.03), lymphvascular space invasion (OR 4.97), tumor stage (OR 2.22) and depth of infiltration (OR 1.08) showed an association with the prevalence of LN metastases. Regarding the number of metastatic LNs, only tumor stage (OR 2.21) or, if excluded, tumor diameter (OR 1.02) were tested significant. CONCLUSION: This large analysis of the multicenter AGO-CaRE-1-study identified lymphvascular space invasion, tumor stage, and depth of infiltration as factors with the strongest association regarding the prevalence of LN metastasis. Interestingly, tumor stage or, if excluded, tumor diameter were the only factors associated with the prevalence as well as the extent of LN metastases.

Impact of intratumoral heterogeneity of breast cancer tissue on quantitative metabolomics using high-resolution magic angle spinning 1 H NMR spectroscopy.

High-resolution magic angle spinning (HR MAS) nuclear magnetic resonance (NMR) spectroscopy is increasingly being used to study metabolite levels in human breast cancer tissue, assessing, for instance, correlations with prognostic factors, survival outcome or therapeutic response. However, the impact of intratumoral heterogeneity on metabolite levels in breast tumor tissue has not been studied comprehensively. More specifically, when biopsy material is analyzed, it remains questionable whether one biopsy is representative of the entire tumor. Therefore, multi-core sampling (n = 6) of tumor tissue from three patients with breast cancer, followed by lipid (0.9- and 1.3-ppm signals) and metabolite quantification using HR MAS 1 H NMR, was performed, resulting in the quantification of 32 metabolites. The mean relative standard deviation across all metabolites for the six tumor cores sampled from each of the three tumors ranged from 0.48 to 0.74. This was considerably higher when compared with a morphologically more homogeneous tissue type, here represented by murine liver (0.16-0.20). Despite the seemingly high variability observed within the tumor tissue, a random forest classifier trained on the original sample set (training set) was, with one exception, able to correctly predict the tumor identity of an independent series of cores (test set) that were additionally sampled from the same three tumors and analyzed blindly. Moreover, significant differences between the tumors were identified using one-way analysis of variance (ANOVA), indicating that the intertumoral differences for many metabolites were larger than the intratumoral differences for these three tumors. That intertumoral differences, on average, were larger than intratumoral differences was further supported by the analysis of duplicate tissue cores from 15 additional breast tumors. In summary, despite the observed intratumoral variability, the results of the present study suggest that the analysis of one, or a few, replicates per tumor may be acceptable, and supports the feasibility of performing reliable analyses of patient tissue.

Outcome After Sentinel Lymph Node Dissection in Vulvar Cancer: A Subgroup Analysis of the AGO-CaRE-1 Study.

PURPOSE: Analyzing the large patient cohort of the multicenter AGO-CaRE-1 study, we compared isolated sentinel lymph node dissection (SLND) with radical lymph node dissection (LND) of the groin in relation to recurrence rates and survival. METHODS: The AGO-CaRE-1 study retrospectively collected data on treatment patterns and follow-up of vulvar cancer patients [International Federation of Gynecology and Obstetrics (FIGO) stage ≥1B] treated at 29 gynecologic cancer centers between 1998 and 2008. This subgroup analysis evaluated the influence of SLND alone on progression-free survival (PFS) and overall survival (OS). RESULTS: In 487 (63.1%) of 772 included patients with tumors smaller than 4 cm, an LND was performed and no metastatic lymph nodes were detected (LN0). Another 69/772 (8.9%) women underwent SLND alone, showing a negative SLN (SLN0). Tumors in the LN0 group were larger and showed a deeper invasion (LN0 vs. SLN0 tumor diameter: 20.0 vs. 13.0 mm, p < 0.001; depth of invasion: 4.0 vs. 3.0 mm, p = 0.002). After a median follow-up of 33 months (0-156), no significant differences in relation to isolated groin recurrence rates (SLN0 3.0% vs. LN0 3.4%, p = 0.845) were detected. Similarly, univariate 3-year PFS analysis showed no significant differences between both groups (SLN0 82.7% vs. LN0 77.6%, p = 0.230). A multivariate Cox regression analysis, including tumor diameter, depth of invasion, age, grading, and lymphovascular space invasion was performed: PFS [hazard ratio (HR) 0.970, 95% confidence interval (CI) 0.517-1.821] and OS (HR 0.695, 95% CI 0.261-1.849) did not differ significantly between both cohorts. CONCLUSION: This subgroup analysis of the large AGO-CaRE-1 study showed similar results for groin LND and SLND alone with regard to recurrence rates and survival in node-negative patients with tumors <4 cm.

Role of tumour-free margin distance for loco-regional control in vulvar cancer-a subset analysis of the Arbeitsgemeinschaft Gynäkologische Onkologie CaRE-1 multicenter study.

AIM OF THE STUDY: A tumour-free pathological resection margin of ≥8 mm is considered state-of-the-art. Available evidence is based on heterogeneous cohorts. This study was designed to clarify the relevance of the resection margin for loco-regional control in vulvar cancer. METHODS: AGO-CaRE-1 is a large retrospective study. Patients (n = 1618) with vulvar cancer ≥ FIGO stage IB treated at 29 German gynecologic-cancer-centres 1998-2008 were included. This subgroup analysis focuses on solely surgically treated node-negative patients with complete tumour resection (n = 289). RESULTS: Of the 289 analysed patients, 141 (48.8%) had pT1b, 140 (48.4%) pT2 and 8 (2.8%) pT3 tumours. One hundred twenty-five (43.3%) underwent complete vulvectomy, 127 (43.9%) partial vulvectomy and 37 (12.8%) radical local excision. The median minimal resection margin was 5 mm (1 mm-33 mm); all patients received groin staging, in 86.5% with full dissection. Median follow-up was 35.1 months. 46 (15.9%) patients developed recurrence, thereof 34 (11.8%) at the vulva, after a median of 18.3 months. Vulvar recurrence rates were 12.6% in patients with a margin <8 mm and 10.2% in patients with a margin ≥8 mm. When analysed as a continuous variable, the margin distance had no statistically significant impact on local recurrence (HR per mm increase: 0.930, 95% CI: 0.849-1.020; p = 0.125). Multivariate analyses did also not reveal a significant association between the margin and local recurrence neither when analysed as continuous variable nor categorically based on the 8 mm cutoff. Results were consistent when looking at disease-free-survival and time-to-recurrence at any site (HR per mm increase: 0.949, 95% CI: 0.864-1.041; p = 0.267). CONCLUSIONS: The need for a minimal margin of 8 mm could not be confirmed in the large and homogeneous node-negative cohort of the AGO-CaRE database.

Choline-releasing glycerophosphodiesterase EDI3 drives tumor cell migration and metastasis.

Metastasis from primary tumors remains a major problem for tumor therapy. In the search for markers of metastasis and more effective therapies, the tumor metabolome is relevant because of its importance to the malignant phenotype and metastatic capacity of tumor cells. Altered choline metabolism is a hallmark of cancer. More specifically, a decreased glycerophosphocholine (GPC) to phosphocholine (PC) ratio was reported in breast, ovarian, and prostate cancers. Improved strategies to exploit this altered choline metabolism are therefore required. However, the critical enzyme cleaving GPC to produce choline, the initial step in the pathway controlling the GPC/PC ratio, remained unknown. In the present work, we have identified the enzyme, here named EDI3 (endometrial differential 3). Purified recombinant EDI3 protein cleaves GPC to form glycerol-3-phosphate and choline. Silencing EDI3 in MCF-7 cells decreased this enzymatic activity, increased the intracellular GPC/PC ratio, and decreased downstream lipid metabolites. Downregulating EDI3 activity inhibited cell migration via disruption of the PKCα signaling pathway, with stable overexpression of EDI3 showing the opposite effect. EDI3 was originally identified in our screening study comparing mRNA levels in metastasizing and nonmetastasizing endometrial carcinomas. Both Kaplan-Meier and multivariate analyses revealed a negative association between high EDI3 expression and relapse-free survival time in both endometrial (P < 0.001) and ovarian (P = 0.029) cancers. Overall, we have identified EDI3, a key enzyme controlling GPC and choline metabolism. Because inhibition of EDI3 activity corrects the GPC/PC ratio and decreases the migration capacity of tumor cells, it represents a possible target for therapeutic intervention.

Vascular endothelial growth factor gene polymorphisms in ovarian cancer.

BACKGROUND: Polymorphisms within the vascular endothelial growth factor (VEGF) gene, the most important regulator of angiogenesis and vascular permeability, were shown to be independently associated with an impaired prognosis in various malignancies. No data have been reported in ovarian cancer. METHODS: In the present multi-center study, we examined three common polymorphisms within the VEGF gene (VEGF +405G/C, VEGF -460C/T, and VEGF +936C/T) in 553 Caucasian patients with ovarian cancer using pyrosequencing. RESULTS: The three investigated polymorphisms did not correlate with any of the investigated clinico-pathological parameters. In univariate and multivariate models, only FIGO stage and patient's age at diagnosis, but not any polymorphism or any haplotype were correlated with patients' overall survival. CONCLUSIONS: In our large multi-center study, the investigated VEGF gene polymorphisms were not associated with prognosis in patients with ovarian cancer.

Vascular endothelial growth factor gene polymorphisms are associated with prognosis in ovarian cancer.

PURPOSE: Vascular endothelial growth factor (VEGF), an important regulator of angiogenesis and vascular permeability, is involved in various steps of ovarian carcinogenesis. Gene polymorphisms within the gene encoding VEGF were shown to be independently associated with an adverse outcome in various malignancies. No data are available for ovarian cancer. EXPERIMENTAL DESIGN: In the present multicenter study, we examined three common polymorphisms within the VEGF gene (-634G/C, -1154G/A, and -2578C/A) known to be associated with an increased VEGF production in 563 Caucasian patients with ovarian cancer from Austria and Germany using pyrosequencing. Results were correlated with clinical data. RESULTS: The three investigated polymorphisms did not correlate with any of the investigated clinicopathologic variables. In univariate and multivariate models, no significant correlations between any polymorphism and patients' overall survival were ascertained. Simultaneous carriage of the three homozygous genotypes (i.e., VEGF -634C/C, VEGF -1154G/G, VEGF -2578C/C) known to be associated with increased VEGF expression in an individual patient, however, was independently associated with a shortened overall survival (hazard ratio, 2.1; 95% confidence interval, 1.1-3.9; P=0.02). CONCLUSIONS: We present the first data on VEGF gene polymorphisms in ovarian cancer. Simultaneous carriage of the three investigated homozygous genotypes was shown to be an independent adverse prognosticator of overall survival.

Surgery in recurrent ovarian cancer: the Arbeitsgemeinschaft Gynaekologische Onkologie (AGO) DESKTOP OVAR trial.

BACKGROUND: The role of cytoreductive surgery in relapsed ovarian cancer is not clearly defined. Therefore, patient selection remains arbitrary and depends on the center's preference rather than on established selection criteria. The Descriptive Evaluation of preoperative Selection KriTeria for OPerability in recurrent OVARian cancer (DESKTOP OVAR) trial was undertaken to form a hypothesis for a panel of criteria for selecting patients who might benefit from surgery in relapsed ovarian cancer. METHODS: The DESKTOP trial was an exploratory study based on data from a retrospective analysis of hospital records. Twenty-five member institutions of the Arbeitsgemeinschaft Gynaekologische Onkologie Ovarian Committee (AGO OC) and AGO-OVAR boards collected data on their patients with cytoreductive surgery for relapsed invasive epithelial ovarian cancer performed in 2000-2003. RESULTS: Two hundred and sixty-seven patients were included. Complete resection was associated with significantly longer survival compared with surgery leaving any postoperative residuals [median 45.2 vs. 19.7 months; hazard ratio (HR) 3.71; 95% confidence interval (CI) 2.27-6.05; P < .0001]. Variables associated with complete resection were performance status (PS) [Eastern Cooperative Oncology Group (ECOG) 0 vs. > 0; P < .001], International Federation of Gynecology and Obstetrics (FIGO) stage at initial diagnosis (FIGO I/II vs. III/IV, P = .036), residual tumor after primary surgery (none vs. present, P <.001), and absence of ascites > 500 ml (P < .001). A combination of PS, early FIGO stage initially or no residual tumor after first surgery, and absence of ascites could predict complete resection in 79% of patients. CONCLUSIONS: Only complete resection was associated with prolonged survival in recurrent ovarian cancer. The identified criteria panel will be verified in a prospective trial (AGO-DESKTOP II) evaluating whether it will render a useful tool for selecting the right patients for cytoreductive surgery in recurrent ovarian cancer.

ErbB-3 predicts survival in ovarian cancer.

BACKGROUND: HER3 (erbB-3) is a member of the epidermal growth factor receptor (EGFR) family. After dimerization with other members of the EGFR family several signal transduction cascades can be activated, including phosphoinosite 3'-kinase (PI3-K)/Akt and extracellular signal-regulated kinase (ERK1/2). Here, we studied a possible association between HER3 expression and prognosis in patients with ovarian cancer. METHODS: Tumor tissue of 116 consecutive patients diagnosed with primary epithelial ovarian cancer between 1986 and 1995 was analyzed immunohistochemically for HER3 expression. A possible influence of HER3 expression on survival was studied by multivariate Cox regression adjusting for established clinical prognostic factors. RESULTS: A positive HER3 expression was observed in 53.4% of the patients. HER3 expression was associated with decreased survival in proportional hazard modeling, including the International Federation of Gynecology and Obstetrics (FIGO) stage, histologic grade and type, residual disease, and age. After likelihood ratio forward as well as backward selection, only HER3 expression (hazard ratio, 1.71; 95% CI, 1.10 to 2.67; P = .018), FIGO stage (hazard ratio, 4.78; 95% CI, 1.89 to 12.08; P = .001), residual tumor (hazard ratio, 2.69; 95% CI, 1.40 to 5.17; P = .003), and age (hazard ratio, 2.06; 95% CI, 1.17 to 3.65; P = .013) were found to be significant. Kaplan-Meier plots demonstrated a clear influence of HER3 expression on survival time. Median survival time was 3.31 years (95% CI, 1.93 to 4.68) for patients with low HER3 expression, compared with only 1.80 years (95% CI, 0.83 to 2.78) for patients with HER3 overexpression (log-rank test P = .0034). CONCLUSION: HER3 may represent a new prognostic factor in primary epithelial ovarian cancer. Pending validation, exploration of therapeutic strategies to block HER3 could be warranted.

Dephosphorylation of p-ERK1/2 in relation to tumor remission after HER-2 and Raf1 blocking therapy in a conditional mouse tumor model.

Several studies have shown that HER-2/neu (erbB-2) blocking therapy strategies can cause tumor remission. However, the responsible molecular mechanisms are not yet known. Both ERK1/2 and Akt/PKB are critical for HER-2-mediated signal transduction. Therefore, we used a mouse tumor model that allows downregulation of HER-2 in tumor tissue by administration of anhydrotetracycline (ATc). Switching-off HER-2 caused a rapid tumor remission by more than 95% within 7 d of ATc administration compared to the volume before switching-off HER-2. Interestingly, HER-2 downregulation caused a dephosphorylation of p-ERK1/2 by more than 80% already before tumor remission occurred. Levels of total ERK protein were not influenced. In contrast, dephosphorylation of p-Akt occurred later, when the tumor was already in remission. These data suggest that in our HER-2 tumor model dephosphorylation of p-ERK1/2 may be more critical for tumor remission than dephosphorylation of p-Akt. To test this hypothesis we used a second mouse tumor model that allows ATc controlled expression of BXB-Raf1 because the latter constitutively signals to ERK1/2, but cannot activate Akt/PKB. As expected, downregulation of BXB-Raf1 in tumor tissue caused a strong dephosphorylation of p-ERK1/2, but did not decrease levels of p-Akt. Interestingly, tumor remission after switching-off BXB-Raf1 was similarly efficient as the effect of HER-2 downregulation, despite the lack of p-Akt dephosphorylation. In conclusion, two lines of evidence strongly suggest that dephosphorylation of p-ERK1/2 and not that of p-Akt is critical for the rapid tumor remission after downregulation of HER-2 or BXB-Raf1 in our tumor model: (i) dephosphorylation of p-ERK1/2 but not that of p-Akt precedes tumor remission after switching-off HER-2 and (ii) downregulation of BXB-Raf1 leads to a similarly efficient tumor remission as downregulation of HER-2, although no p-Akt dephosphorylation was observed after switching-off BXB-Raf1.

SPOC1, a novel PHD-finger protein: association with residual disease and survival in ovarian cancer.

We report the identification of a novel human gene (SPOC1) which encodes a protein with a PHD-finger domain. The gene is located in chromosomal region 1p36.23, a region implicated in tumor development and progression. RNA in situ hybridization experiments showed strong SPOC1 expression in some rapidly proliferating cell types, such as spermatogonia, but not in nonproliferating mature spermatocytes. In addition, high SPOC1 mRNA expression was observed in several ovarian cancer cell lines. This prompted us to systematically examine SPOC1 expression in ovarian cancer in relation to prognosis. SPOC1 mRNA expression was quantified in tumor tissue of 103 patients with epithelial ovarian cancer. Interestingly, SPOC1 was associated with residual disease, whereby patients with unresectable tumors showed higher levels compared to patients without residual tumor tissue after surgery (p = 0.029). The univariable proportional hazards model showed an association between SPOC1 expression and survival (p = 0.043, relative risk = 1.535). Median survival time was 1,596 days for patients with low SPOC1 expression vs. only 347 days for patients with high expression, using Kaplan-Meier analysis. However, SPOC1 was not associated with survival when multivariable analysis was adjusted for residual disease. This can be explained by the correlation between residual disease and SPOC1 expression. In conclusion, SPOC1 is a novel PHD-finger protein showing strong expression in spermatogonia and ovarian cancer cells. SPOC1 overexpression was associated with unresectable carcinomas and shorter survival in ovarian cancer.

Long-term prognostic significance of HER-2/neu in untreated node-negative breast cancer depends on the method of testing.

INTRODUCTION: The prognostic significance of HER-2/neu in breast cancer is a matter of controversy. We have performed a study in 101 node-negative breast cancer patients with long-term follow-up not treated in the adjuvant setting, and analysed the prognostic significance of immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), both separately and in combination, in comparison with traditional prognostic factors. METHODS: Overexpression was classified semiquantitatively according to a score (0 to 3+) (HER-2_SCO). FISH was used to analyse HER2/neu amplification (HER-2_AMP). Patients classified 2+ by IHC were examined with FISH for amplification (HER-2_ALG). Patients with 3+ overexpression as well as amplification of HER-2/neu were positive for the combined variable HER2_COM. These variables were compared with tumour size, histological grade and hormone receptor status. RESULTS: HER-2_SCO was 3+ in 20% of all tumours. HER-2_ALG was positive in 22% and amplification (HER-2_AMP) was found in 17% of all tumours. Eleven percent of the tumours showed simultaneous 3+ overexpression and amplification. Only histological grade (relative risk [RR] 3.22, 95% confidence interval [CI] 1.73-5.99, P = 0.0002) and HER-2_AMP (RR 2.47, 95% CI 1.12-5.48, P = 0.026) were significant for disease-free survival in multivariate analysis. For overall survival, both histological grade (RR 3.89, 95% CI 1.77-8.55, P = 0.0007) and HER-2_AMP (RR 3.08, 95% CI 1.24-7.66, P = 0.016) retained their independent significance. CONCLUSION: The prognostic significance of HER-2/neu in node-negative breast cancer depends on the method of testing: only the amplification of HER-2/neu is an independent prognostic factor for the long-term prognosis of untreated node-negative breast cancer.

Nuclear expression of apurinic/apyrimidinic endonuclease increases with progression of ovarian carcinomas.

OBJECTIVE: Apurinic/apyrimidinic endonuclease (APE alias Ref-1) is a key enzyme in the base excision repair pathway. Besides its function in DNA repair, APE serves to maintain several transcription factors in an active reduced state such as c-Fos, c-Jun, NF-kappaB, p53 and HIF-1alpha, all of which have been shown to play a role in tumorigenesis. Because of the importance of APE in maintaining genomic stability and gene regulation, we examined whether APE expression is associated with survival and histopathological parameters of patients with ovarian cancer. METHODS: Tissue sections of primary epithelial ovarian carcinomas from 141 patients were immunostained using a monoclonal antibody directed against APE. RESULTS: Nuclear expression of APE was clearly associated with progression of ovarian carcinomas. Patients with Federation of Gynecology and Obstetrics (FIGO) stages III and IV showed a higher nuclear APE expression level than patients with FIGO stages I and II (P < 0.0001). Similarly, nuclear APE expression was associated with histological grading (grade 1 vs. 2 vs. 3; P = 0.025). In contrast, cytoplasmic and stromal APE expression were not associated with progression. The fraction of APE-positive nuclei (P = 0.0185), the intensity of nuclear staining (P = 0.0496) and a combination of both (P = 0.0070) were associated with survival of ovarian cancer patients, as evidenced by a univariable proportional hazards model. CONCLUSIONS: Multivariable analysis, adjusted to FIGO stage, histological grade and type as well as residual tumor after surgery showed that APE is not independent from "classical" prognostic factors of ovarian cancer. An unexpected observation was the inverse correlation between nuclear and cytoplasmic expression of APE. Tumors with strong cytoplasmic APE reactivity showed a higher fraction of APE-negative nuclei than tumors with weak or negative cytoplasmic APE expression (P = 0.045). This suggests that nuclear translocation of APE is impaired during ovarian carcinogenesis. In conclusion, we have shown that nuclear APE expression increases during tumor progression. This suggests that increased base excision repair capacity and/or APE-mediated activation of transcription factors may contribute to more aggressive proliferation of ovarian carcinomas.

Switching off HER-2/neu in a tetracycline-controlled mouse tumor model leads to apoptosis and tumor-size-dependent remission.

Overexpression of the receptor tyrosine kinase HER-2/neu is associated with poor prognosis in patients with breast and ovarian cancer. Recent excitement has surrounded the therapeutic effects of HER-2-blocking therapy strategies and has rekindled interest on the molecular mechanisms of HER-2/neu in tumor biology. To study the role of HER-2/neu overexpression in vivo, we used a murine fibroblast cell line (NIH3T3-her2) conditionally expressing human HER-2/neu under control of a tetracycline-responsive promoter. Expression of HER-2 could be down-regulated below detection limit (>625-fold dilution) by exposure of NIH3T3-her2 cells to anhydrotetracycline (ATc). Subcutaneous injection of NIH3T3-her2 cells into nude mice resulted in rapid tumor growth. Mice with mean tumor volumes of 0.2, 0.8, 1.9, and 14.9 cm(3) were treated daily with 10 mg/kg ATc to switch off HER-2/neu expression, producing reductions in tumor size of 100, 98.1, 81.4, and 74.2%, respectively, by 7 days after onset of ATc administration (P = 0.005, Kruskal-Wallis test). Different long-term effects of HER-2 down-regulation were observed when mice with small (0.2 cm(3); n = 7), intermediate (0.8-1.2 cm(3); n = 10) and large (> or =1.9 cm(3); n = 11) tumors received ATc for up to 40 days. Complete remission was observed for 100, 40, and 18% of the small-, intermediate-, and large-sized tumors, respectively (P = 0.003). However, after 20-45 days of ATc administration, recurrent tumor growth was observed for all mice, even in those with previous complete remissions. The time periods for which mean tumor volume could be suppressed to volumes <0.1 cm(3) under ATc administration were 34, 22, 8, and 0 days for tumors with initial volumes of 0.2, 0.8, 1.9 and 14.9 cm(3), respectively (P = 0.005, Kruskal-Wallis test). Interestingly, HER-2 remained below the detection limit in recurrent tumor tissue, suggesting that initially HER-2-dependent tumors switched to HER-2 independence. The "second hits" leading to HER-2-independent tumor growth have not yet been identified. The rapid regression of tumors after down-regulation of HER-2 was explained by two independent mechanisms: (a) a block in cell cycle progression, as evidenced by a decrease in Ki-67 antigen expression from 40% before ATc treatment to 8.3% after 7 days of ATc treatment; and (b) induction of apoptosis as demonstrated by caspase-3 activation and by the terminal deoxynucleotidyltransferase (Tdt)-mediated nick end labeling assay (TUNEL). In conclusion, we have shown that switching off HER-2 may disturb the sensitive balance between cell proliferation and cell death, leading to apoptosis and tumor remission. Tumor remission was dependent on the volume of the tumors before down-regulation of HER-2/neu.