Dietary topoisomerase II-poisons

DNA topoisomerases are nuclear enzymes inducing transient breaks in the DNA allowing DNA strands or double helices to pass through each other. The clinically used DNA topoisomerase II-poison etoposide is known to induce DNA double strand breaks leading to chromosomal aberrations and leukemias. Recently, some alarming studies have been published, suggesting that maternal exposure to low doses of dietary topoisomerase II-poisons, including bioflavonoids such as genistein or quercetin, may contribute to the development of infant leukemia: approximately 80% of infants with acute myelogenous leukemia (AML) and acute lymphoblastic leukemia (ALL) have chromosome translocations involving the MLL (mixed lineage leukemia) gene. It has been shown that antineoplastic chemotherapy with the leukemogenic topoisomerase II-poison etoposide induced identical chromosomal aberrations involving the MLL gene compared to children with infant leukemia. Interestingly, the MLL cleavage sites induced by etoposide colocalized with the cleavage sites observed in infant leukemia. In addition, an almost 10-fold higher risk of infant AML has been reported for mothers consuming relatively high levels of topoisomerase II-poison containing foods. These observations are relevant, since many foods contain topoisomerase II-poisons, predominantly soy and soy products, but also coffee, wine, tea, cocao, as well as some fruits and vegetables. Further studies on the role of dietary topoisomerase II-poisons are urgently required. If the causal relationship between dietary exposure to topoisomerase II-poisons and infant leukemia will be confirmed, care should be taken to reduce exposure to critical foods during pregnancy

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

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. (C) 2019 Elsevier Inc. All rights reserved

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 221) 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. (C) 2019 Elsevier Inc. All rights reserved

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

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

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. 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). 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. 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