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Showing papers by "Klaus Pantel published in 2012"


Journal ArticleDOI
TL;DR: This is the first study to document the capacity of circulating miRNAs to indicate CTC status and their potential as prognostic markers in patients with MBC.
Abstract: Purpose: The use of circulating tumor cells (CTC) as a prognostic marker in metastatic breast cancer (MBC) has been well established. However, their efficacy and accuracy are still under scrutiny mainly because of methods of their enrichment and identification. We hypothesized that circulating miRNAs can predict the CTC status of patients with MBC, and tested for the same. Furthermore, we aimed at establishing a panel of circulating miRNAs capable of differentiating MBC cases from healthy controls. Experimental Design: Circulating miRNAs from plasma of CTC-positive and CTC-negative patients with MBC, and healthy controls, were profiled by TaqMan Human MicroRNA arrays. Candidates from the initial screen were validated in an extended cohort of 269 individuals (61 CTC-positive, 72 CTC-negative, 60 CTC-low MBC cases, and 76 controls). Results: CTC-positive had significantly higher levels of miR-141, miR-200a, miR-200b, miR-200c, miR-203, miR-210, miR-375, and miR-801 than CTC-negative MBC and controls ( P P Conclusion: This is the first study to document the capacity of circulating miRNAs to indicate CTC status and their potential as prognostic markers in patients with MBC. Clin Cancer Res; 18(21); 5972–82. ©2012 AACR .

252 citations


Journal ArticleDOI
TL;DR: Patients with benign inflammatory colon diseases in particular can harbor viable circulating epithelial cells that are detectable with current CTC assays, and this finding points to the need for further molecular characterization of circulating epitocytes and has important implications for the use of CTC testing.
Abstract: BACKGROUND: Detection of circulating tumor cells (CTCs) in the peripheral blood is a rapidly developing research field with clear clinical implications for the staging and monitoring of cancer patients. Current CTC assays, including the US Food and Drug Administration–cleared CellSearch® system, typically use markers [e.g., cytokeratins (CKs), the transmembrane protein EpCAM (epithelial cell adhesion molecule)] that are expressed on normal and malignant epithelial cells but not on the surrounding normal leukocytes. METHODS: We enrolled 53 patients with benign colon diseases (e.g., diverticulosis, benign polyps, Crohn disease, ulcerative rectocolitis, colonic endometriosis) and analyzed their peripheral blood with 2 previously validated CTC assays: the epithelial immunospot (EPISPOT) assay and the CellSearch system. The EPISPOT assay detects only viable, CK19-releasing CTCs that were enriched by depletion of CD45+ leukocytes, whereas the CellSearch system detects CK-positive CTCs after positive EpCAM-based immunomagnetic enrichment. RESULTS: In patients with benign colon diseases, positive events that met the criteria for “tumor cells” were detected with both the CellSearch system (11.3%) and the CK19-EPISPOT assay (18.9%), whereas no positive events were detected in samples from healthy volunteers. Positive events were detected most frequently in patients with diverticulosis and Crohn disease. All positive events lacked expression of CD45, a common leukocyte antigen. CONCLUSIONS: These results indicate that patients with benign inflammatory colon diseases in particular can harbor viable circulating epithelial cells that are detectable with current CTC assays. This finding points to the need for further molecular characterization of circulating epithelial cells and has important implications for the use of CTC testing.

231 citations


Journal ArticleDOI
TL;DR: The DETECT trial for metastatic breast cancer patients was designed to directly compare the prognostic impact of two commercially available CTC assays that are prominent representatives of immunocytochemical and RT-PCR based technologies and indicates that the CellSearch system is superior to the Adna test in predicting clinical outcome in advanced breast cancer.
Abstract: There is a multitude of assays for the detection of circulating tumor cells (CTCs) but a very limited number of studies comparing the clinical relevance of results obtained with different test methods. The DETECT trial for metastatic breast cancer patients was designed to directly compare the prognostic impact of two commercially available CTC assays that are prominent representatives of immunocytochemical and RT-PCR based technologies. In total, 254 metastatic breast cancer patients were enrolled in this prospective multicenter trial. CTCs were assessed using both the AdnaTest Breast Cancer and the CellSearch system according to the manufacturers' instructions. With the CellSearch system, 116 of 221 (50%) evaluable patients were CTC-positive based on a cut-off level at 5 or more CTCs. The median overall survival (OS) was 18.1 months in CTC-positive patients. (95%-CI: 15.1-22.1 months) compared to 27 months in CTC-negative patients (23.5-30.7 months; p<0.001). This prognostic impact for OS was also significant in the subgroups of patients with triple negative, HER2-positive and hormone receptor-positive/HER2-negative primary tumors. The progression free survival (PFS) was not correlated with CTC status in our cohort receiving different types and lines of systemic treatment (p = 0.197). In multivariate analysis, the presence of CTCs was an independent predictor for OS (HR: 2.7, 95%-CI: 1.6-4.2). When the AdnaTest Breast was performed, 88 of 221 (40%) patients were CTC-positive. CTC-positivity assessed by the AdnaTest Breast had no association with PFS or OS. The prognostic relevance of CTC detection in metastatic breast cancer patients depends on the test method. The present results indicate that the CellSearch system is superior to the AdnaTest Breast Cancer in predicting clinical outcome in advanced breast cancer. Current Controlled Trials Registry number ISRCTN59722891 .

175 citations


Journal ArticleDOI
TL;DR: In this article, the diagnostic potential of circulating cell-free microRNAs targeting PTEN in breast cancer was examined on pre-operative serum samples of 102 patients with early breast cancer and a subset of 34 post-operative samples, as well as of 32 patients with benign breast disease and 53 healthy women.
Abstract: MicroRNAs play a role in breast cancer development and progression by post-transcriptional repression of the expression of important genes, such as the tumor suppressor gene phosphatase and tensin homolog (PTEN). The focus of the current study was to examine the diagnostic potential of circulating cell-free microRNAs targeting PTEN in breast cancer. Our analyses were performed on preoperative serum samples of 102 patients with early breast cancer and a subset of 34 postoperative samples, as well as of 32 patients with benign breast disease and 53 healthy women. The relative concentrations of four circulating microRNAs (miR-19a, miR-20a, miR-21, and miR-214) in blood serum were measured by TaqMan MicroRNA assays. Levels of preoperative serum miR-20a and miR-21 were significantly higher in patients with breast cancer and benign disease than in healthy women (p = 0.0001), but only serum miR-214 could discriminate malignant from benign tumors and healthy controls (p = 0.0001) with an area under the curve of 0.878 and 0.883 in ROC analysis, respectively. Moreover, miR-214 levels significantly decreased in the postoperative serum samples (p = 0.0001) as compared to the preoperative samples. The comparison with the clinicopathologic data of the breast cancer patients showed that increased miR-214 levels were associated with a positive lymph node status (p = 0.039). Our data show that circulating, cell-free miR-214 has diagnostic potential in breast cancer as indicator of malignant disease and metastatic spread to regional lymph nodes. Since PTEN is an important target gene of miR-214, this finding could also have potential implications for therapeutic approaches.

144 citations


Journal ArticleDOI
TL;DR: Breast cancer cells show a complex pattern of keratin expression with potential biologic relevance and individual keratin antibodies recognizing only a limited set of keratins inherit the risk to miss biologically relevant CTCs in cancer patients, and antibody cocktails including these keratin are recommended.
Abstract: Purpose: Circulating tumor cells (CTC) might function as early markers for breast cancer metastasis or monitoring therapy efficacy. Enrichment and identification of CTCs are based on epithelial markers that might be modulated during epithelial–mesenchymal transition. Little is known about the expression of keratins in CTCs and whether all CTCs can be detected with antibodies directed against a limited panel of keratins. Experimental Design: Protein expression of keratin 2, 4–10, 13–16, 18, and 19 were assessed by a cocktail of antibodies (C11, AE1, AE3, and K7) and keratin antibodies C11 and A45-B/B3 alone in 11 breast cancer cell lines and 50 primary breast carcinomas and their lymph node metastases. Furthermore, CTCs were assessed in blood of 70 metastatic breast cancer patients. Results: Claudin-low cell lines did not show expression of normal breast epithelial keratins but were positive for K14 and K16, detected by the cocktail only. Primary breast carcinomas showed changes in keratin expression during metastatic progression to the lymph nodes. In 35 of 70 patients CTCs were identified, of which 83%, 40%, and 57% were identified by the cocktail, C11 and A45-B/B3, respectively. Identification of CTCs by the cocktail was associated with shorter survival ( P < 0.01). In silico analyses revealed association between KRT16 expression and shorter relapse-free survival in metastatic breast cancer. Conclusion: Breast cancer cells show a complex pattern of keratin expression with potential biologic relevance. Individual keratin antibodies recognizing only a limited set of keratins inherit the risk to miss biologically relevant CTCs in cancer patients, and antibody cocktails including these keratins are therefore recommended. Clin Cancer Res; 18(4); 993–1003. ©2012 AACR . This article is featured in Highlights of This Issue, [p. 915][1] [1]: /lookup/volpage/18/915?iss=4

139 citations


Journal ArticleDOI
TL;DR: It is demonstrated that brain metastases often show very complex genomic-aberration patterns, suggesting a potential role of PTEN and EGFR in brain metastasis formation.
Abstract: With the improvement of therapeutic options for the treatment of breast cancer, the development of brain metastases has become a major limitation to life expectancy in many patients. Therefore, our aim was to identify molecular markers associated with the development of brain metastases in breast cancer. Patterns of chromosomal aberrations in primary breast tumors and brain metastases were compared with array-comparative genetic hybridization (CGH). The most significant region was further characterized in more detail by microsatellite and gene-expression analysis, and finally, the possible target gene was screened for mutations. The array CGH results showed that brain metastases, in general, display similar chromosomal aberrations as do primary tumors, but with a notably higher frequency. Statistically significant differences were found at nine different chromosomal loci, with a gain and amplification of EGFR (7p11.2) and a loss of 10q22.3-qter being among the most significant aberrations in brain metastases (P < 0.01; false discovery rate (fdr) < 0.04). Allelic imbalance (AI) patterns at 10q were further verified in 77 unmatched primary tumors and 21 brain metastases. AI at PTEN loci was found significantly more often in brain metastases (52%) and primary tumors with a brain relapse (59%) compared with primary tumors from patients without relapse (18%; P = 0.003) or relapse other than brain tumors (12%; P = 0.006). Loss of PTEN was especially frequent in HER2-negative brain metastases (64%). Furthermore, PTEN mRNA expression was significantly downregulated in brain metastases compared with primary tumors, and PTEN mutations were frequently found in brain metastases. These results demonstrate that brain metastases often show very complex genomic-aberration patterns, suggesting a potential role of PTEN and EGFR in brain metastasis formation.

91 citations


Journal ArticleDOI
TL;DR: The data indicate the important role in EGFR, HER2 and HER3 lateral signalling in breast cancer cell migration and show that primary tumour cells and DTCs can vary in their HER activation status, which is important to know in the context of cancer therapy.
Abstract: HER2 signalling by heterodimerisation with EGFR and HER3 in breast cancer is associated with worst outcome of the afflicted patients, which is attributed not only to the aggressiveness of such tumours but also to therapy resistance. Thus, in the present study we investigated the role of EGFR, HER2 and HER3 lateral signalling in cell migration by applying the MDA-MB-468-HER2 (MDA-HER2) breast cancer cell line, representing a valid model system. Knockdown of HER3 expression by siRNA resulted in decreased phosphorylated AKT (pAKT) levels, abrogated epidermal growth factor (EGF)-mediated PLC-γ1 activation and a diminished EGF-induced migratory activity, depicting the interplay of EGF receptor (EGFR)/HER2/PLC-γ1 and HER2/HER3/PI3K signalling in mediating the migration of EGFR/HER2/HER3-expressing breast cancer cells. Since therapy failure usually arises from metastatic cells, we further investigated whether HER3 signalling was active in established breast cancer disseminated tumour cell (DTC) lines as well as in primary DTCs derived from breast cancer patients. EGF treatment of DTC lines resulted solely in increased pAKT S473 levels, whereas in MDA-HER2 cells both pAKT S473 and pAKT T308 levels were increased upon EGF stimulation. Moreover, despite active HER3 molecules, as indicated by pTyr1222 staining, about 90% of analysed breast cancer patient DTCs exhibited very low or even no detectable pAKT S473 levels, suggesting that these cells might have fallen into dormancy. In summary, our data indicate the important role in EGFR, HER2 and HER3 lateral signalling in breast cancer cell migration. Moreover, our data further show that primary tumour cells and DTCs can vary in their HER activation status, which is important to know in the context of cancer therapy.

84 citations


Journal ArticleDOI
04 Jun 2012-PLOS ONE
TL;DR: Blood-based microarray profiling of microRNA (miR) expression was performed in preoperative serum of non-small cell lung cancer (NSCLC) patients and 11 healthy individuals, and quantitative assessment of these miRs in blood serum might have diagnostic potential to detect NSCLC, in particular in smokers.
Abstract: The high mortality rate of lung cancer patients is mainly due to the late stage at which lung cancer is diagnosed. For effective cancer prevention programs and early diagnosis, better blood-based markers are needed. Hence, blood-based microarray profiling of microRNA (miR) expression was performed in preoperative serum of 21 non-small cell lung cancer (NSCLC) patients and 11 healthy individuals by microfluid biochips containing 1158 different miRs. Two out of the 30 most dysregulated miRs were further validated in serum of 97 NSCLC patients, 20 patients with benign lung diseases and 30 healthy individuals by TaqMan MicroRNA Assays. Microarray profiling showed that miR-361-3p and miR-625* were significantly down-regulated in serum of lung cancer patients. Their further evaluation by quantitative RT-PCR showed that the levels of miR-361-3p and miR-625* were lower in NSCLC than in benign disease (p = 0.0001) and healthy individuals (p = 0.0001, p = 0.0005, respectively). Moreover, the levels of miR-625* were significantly lower in patients with large cell lung cancer (LCLC, p = 0.014) and smoking patients (p = 0.030) than in patients with adenocarcinoma and non-smoking patients, respectively. A rise in the levels of both miRs was observed in the postoperative samples compared with the preoperative levels (p = 0.0001). Functional analyses showed that Smad2 and TGFs1 are not dysregulated by miR-361-3p and miR-625* in the lung cell line A549, respectively. Our present pilot study suggests that miR-361-3p and miR-625* might have a protective influence on the development of NSCLC, and the quantitative assessment of these miRs in blood serum might have diagnostic potential to detect NSCLC, in particular in smokers.

77 citations


Journal ArticleDOI
TL;DR: The improved detection of LOH on cell-free DNA provides important information on DNA losses of tumor suppressor genes TIG1, PTEN, cyclin D2, RB1, and BRCA1 in breast cancer and might become an important prognostic marker easily detectable in the peripheral blood.
Abstract: Purpose: LOH on circulating DNA may provide tumor-specific information on breast cancer. As identification of LOH on cell-free DNA is impeded by the prevalence of wild type DNA in blood of cancer patients, we fractionated plasma DNA, and determined the diagnostic and prognostic value of both fractions. Experimental design: Our cohort of 388 patients with primary breast cancer before chemotherapy was selected from a multicenter study (SUCCESS). Postoperative plasma was fractionated in low- and high-molecular weight DNA by two different column systems. In both fractions, LOH was determined by a PCR-based microsatellite analysis using a panel of 8 polymorphic markers. Circulating tumor DNA in plasma from 30 patients after chemotherapy was additionally analyzed. The significance levels were adjusted for multiple comparisons. Results: More patients (38%) had LOH at all markers in the fraction containing short DNA fragments than in the fraction containing the long DNA molecules (28%, P = 0.0001). In both fractions 32.85% of LOH were concordant. LOH at the markers D3S1605, D10S1765, D12S1725, D13S218, and D17S855 significantly correlated with tumor stage, tumor size, and lymph node metastasis, positive progesterone, and HER2 receptor status. Most importantly, LOH at D12S1725 mapping to cyclin D2 correlated with shorter overall survival ( P = 0.004). Conclusions: The improved detection of LOH on cell-free DNA provides important information on DNA losses of tumor suppressor genes TIG1, PTEN, cyclin D2, RB1 , and BRCA1 in breast cancer. In particular, loss of the cyclin D2 gene might become an important prognostic marker easily detectable in the peripheral blood. Clin Cancer Res; 18(20); 5719–30. ©2012 AACR .

74 citations


Journal ArticleDOI
TL;DR: A single‐cell array comparative genomic hybridization (SCaCGH) method providing molecular analysis of immunomorphologically detected DTCs is presented and may be a powerful tool for the molecular characterization of D TCs.
Abstract: The presence of disseminated tumor cells (DTCs) in bone marrow (BM) identifies breast cancer patients with less favorable outcome. Furthermore, molecular characterization is required to investigate the malignant potential of these cells. This study presents a single-cell array comparative genomic hybridization (SCaCGH) method providing molecular analysis of immunomorphologically detected DTCs. The resolution limit of the method was estimated using the cancer cell line SK-BR-3 on 44 and 244k arrays. The technique was further tested on 28 circulating tumor cells and four hematopoietic cells (HCs) from peripheral blood (n = 8 patients). The SCaCGH method was finally applied to 24 DTCs, three immunopositive cells morphologically classified as probable HCs from breast cancer patients and five HC controls from BM (n = 7 patients plus n = 1 healthy donor). The frequency of copy number changes of the DTCs revealed similarities with primary breast tumor samples. Three of the patients had available profiles for DTCs and the corresponding tumor tissue from primary surgery. More than two-third of the analyzed DTCs disclosed equivalent changes, both to each other and to the corresponding primary disease, whereas the rest of the cells showed balanced profiles. The probable HCs revealed either balanced profiles (n = 2) or changes comparable to the tumor tissue and DTCs (n = 1), indicating morphological overlap between HCs and DTCs. Similar aberration patterns were visible in DTCs collected at diagnosis and at 3 years relapse-free follow-up. SCaCGH may be a powerful tool for the molecular characterization of DTCs.

53 citations


Journal ArticleDOI
TL;DR: This editorial highlights the current strategies used for enrichment and detection of circulating tumor cells and considers CTC analyses as a real-time “liquid biopsy” in cancer patients.
Abstract: Early during the formation and growth of a primary epithelial tumor, cells disseminate through the bloodstream to distant organs These circulating tumor cells (CTCs) can be enriched and detected via different technologies and CTC analyses are considered as a real-time “liquid biopsy” in cancer patients This biopsy allows the characterization of specific sub-populations of CTCs and may revolutionize cancer detection and management This editorial highlights the current strategies used for enrichment and detection of CTCs

Journal ArticleDOI
TL;DR: Preliminary evidence is provided for the potential clinical utility of ALCAM as a prognostic biomarker for EC and a subset of DTC of the bone marrow indicates a potential function in the metastatic cascade of EC.
Abstract: The expression of the activated leukocyte cell adhesion molecule (ALCAM and CD166) is increased in various types of cancer. We aimed to evaluate its role as a prognostic marker for esophageal cancer (EC). We retrospectively analyzed ALCAM expression in 299 primary lesions, 147 lymph node and 46 distant metastases from EC patients, on a tissue microarray using immunohistochemistry. Bone marrow samples from representative cancer patients (n = 16), taken before primary surgery, were stained by double-immunofluorescence for ALCAM and cytokeratins (CK). Blood serum samples from 236 cancer patients and 127 controls were analyzed for serum ALCAM (s-ALCAM) by ELISA. The immunohistochemical analysis showed increased ALCAM expression in the majority of lesions (primary tumor 71%, lymph node 76% and distant metastases 80%). ALCAM expression was not associated with histopathological parameters except for tumor grading (p = 0.015). ALCAM-positive patients had significantly worse recurrence-free and overall survival (OS; p = 0.002). Disseminated tumor cells (DTC) in bone marrow showed two phenotypes, ALCAM+/CK+ (36%) and ALCAM-/CK+ (64%). Multivariate analysis revealed that ALCAM expression and elevated s-ALCAM serum values are powerful prognostic variables for OS in patients with EC (hazard ratio [HR] 3.987, 95% confidence interval [95%CI] 1.906-8.340, p < 0.001 and HR 1.915, 95%CI 1.021-3.592, p = 0.043). The results of our study provide preliminary evidence for the potential clinical utility of ALCAM as a prognostic biomarker for EC, which might be a basis for future clinical application. In addition, ALCAM expression in a subset of DTC of the bone marrow indicates a potential function in the metastatic cascade of EC.

Journal ArticleDOI
17 Oct 2012-PLOS ONE
TL;DR: The correlation of CXCR4- and HER2-expression and the elevation of Her2- expression and reduction of metastases through CX CR4-inhibition suggest a possible functional linkage and a role in tumor dissemination in HER2 -positive esophageal carcinoma.
Abstract: A functional linkage of the structurally unrelated receptors HER2 and CXCR4 has been suggested for breast cancer but has not been evaluated for esophageal carcinoma. The inhibition of HER2 leads to a reduction of primary tumor growth and metastases in an orthotopic model of esophageal carcinoma. The chemokine receptor CXCR4 has been implicated in metastatic dissemination of various tumors and correlates with poor survival in esophageal carcinoma. The aim of this study was to investigate a correlation between the expression levels of HER2 and CXCR4 and to evaluate the involvemnent of CXCR4-expression in HER2-positive esophageal carcinoma. The effects of HER2-inhibition with trastuzumab and of CXCR4-inhibition with AMD3100 on primary tumor growth, metastatic homing, and receptor expression were evaluated in vitro and in an orthotopic model of metastatic esophageal carcinoma using MRI for imaging. The clinical relevance of HER2- and CXCR4-expression was examined in esophageal carcinoma patients. A significant correlation of HER2- and CXCR4-expression in primary tumor and metastases exists in the orthotopic model. Trastuzumab and AMD3100 treatment led to a significant reduction of primary tumor growth, metastases and micrometastases. HER2-expression was significantly elevated under AMD3100 treatment in the primary tumor and particularly in the metastases. The positive correlation between HER2- and CXCR4-expression was validated in esophageal cancer patients. The correlation of CXCR4- and HER2-expression and the elevation of HER2-expression and reduction of metastases through CXCR4-inhibition suggest a possible functional linkage and a role in tumor dissemination in HER2-positive esophageal carcinoma.

Journal ArticleDOI
TL;DR: The presence of DTC in bone marrow is a strong and independent prognostic factor in patients with resectable EC and was evident in subgroup analysis stratified for nodal status, lymph nodes yield, lymph node ratio, and tumor subtypes.
Abstract: Objective:To assess the impact of disseminated tumor cells (DTC) in bone marrow on recurrence and survival in complete resected esophageal cancer (EC).Background:Current modalities to predict tumor recurrence and survival in EC are insufficient. Here, we evaluated in a prospective study the prognost

Journal ArticleDOI
TL;DR: It is proposed that combination of CTCs and PSA velocity or doubling-time assessments may offer insights into the prognosis and management of advanced PC.
Abstract: Prostate-specific antigen (PSA) has been used for over two decades as a serum marker for adenocarcinoma of the prostate. Although PSA screening remains an important part of disease screening and monitoring in early prostate cancer (PC), its utility in monitoring disease progression in advanced PC is undetermined. Furthermore, the role of PSA monitoring in the management of patients with PC and bone metastases appears limited. The purpose of this review is to evaluate the role of circulating tumor cells (CTCs) as potential novel biomarkers in advanced PC. We present a review of CTC testing and the clinical data supporting the prognostic potential of CTCs in this setting. We propose that combination of CTCs and PSA velocity or doubling-time assessments may offer insights into the prognosis and management of advanced PC.

Journal ArticleDOI
TL;DR: Measurements of androgen receptor (AR) signaling in circulating tumor cells (CTC) enable real-time quantitative monitoring of intratumoral AR signaling, indicating that measuring AR signaling within CTCs may help to guide therapy in metastatic prostate cancer.
Abstract: Summary: Miyamoto and colleagues present data that prostate-specific antigen/prostate-specific membrane antigen (PSA/PSMA)–based measurements of androgen receptor (AR) signaling in circulating tumor cells (CTC) enable real-time quantitative monitoring of intratumoral AR signaling. This finding indicates that measuring AR signaling within CTCs may help to guide therapy in metastatic prostate cancer and highlights the use of CTCs as liquid biopsy. Cancer Discov; 2(11); 974–5. ©2012 AACR . Commentary on Miyamoto et al., [p. 995][1]. [1]: /lookup/volpage/2/995?iss=11

Journal ArticleDOI
TL;DR: The presence of DTC in bone marrow is a strong and independent prognostic factor of survival in patients with pancreatic cancer, and bone‐targeting may be a new future therapeutic option for DTC‐positive patients.
Abstract: Pancreatic cancer is one of the most devastating cancers with a 6-month median survival and a 5-year survival rate of 3–5%. Still important aspects of its aggressive biology remain elusive and advanced therapeutic regimens have not been substantially successful. We investigated the prognostic role of disseminated tumor cells (DTC) in bone marrow, a reservoir for early DTC potentially contributing to metastatic progression, of pancreatic cancer patients. After exclusion of patients with different postsurgery diagnosis or missing DTC status (n = 40) a total of 175 patients remained for final analyses. One-hundred and nineteen patients were male and 96 female with a median age of 67 years, 96 patients underwent complete resection. Bone marrow aspirates taken at primary surgery were analyzed for DTC by an immunocytochemical cytokeratin assay and correlated to survival data. Overall 13.7% of patient samples (24/175) harbored DTC in their bone marrow. Histopathological parameters did not correlate significantly. Univariate survival analysis revealed a borderline significant correlation between DTC and decreased progression-free survival (p = 0.069), and was significant for overall survival (p = 0.036). Regarding patients with resected tumors, the respective p-values were 0.058 for progression-free and 0.016 for overall survival. Importantly, the prognostic influence was independent from other risk factors as shown by multivariate analyses for progression-free (p = 0.030, HR: 2.057; CI (95%): 1.073–3.943) and overall survival (p = 0.006, HR: 2.283; CI (95%): 1.260–4.135). The presence of DTC in bone marrow is a strong and independent prognostic factor of survival in patients with pancreatic cancer. Thus, bone-targeting may be a new future therapeutic option for DTC-positive patients.

Journal ArticleDOI
TL;DR: Results suggest that both FOXA1 and NKX2‐1 may act as lineage‐specific target genes within the 14q amplicon with opposite functions in lung cancer.
Abstract: Gene copy number profiles of primary lung tumors were screened for high-level amplifications. We detected 22 high-level amplifications in various loci, including 14q13. This locus is known to harbor the adenocarcinoma (AC) lineage-specific target gene NKX2-1, which is not expressed in squamous cell carcinoma (SCC). As the 14q amplification was also found in SCC, we investigated whether or not FOXA1 might be the corresponding target gene for SCC. Focusing on these two target genes, we assessed gene amplifications and protein expression of NKX2-1 and FOXA1 in primary lung tumors (n = 554) and brain metastases (n = 68). Primary AC (n = 194) showed positive protein expression of NKX2-1 in 58.2% of the samples compared with 4.2% of primary SCC samples (n = 212). Positive staining for FOXA1 was seen in 34.7% of the SCC samples, which was comparable with 39.6% in the AC samples. For brain metastases, FOXA1 expression was slightly higher in the SCC samples (55.6%) compared with the non-matched primary SCC tumor samples (43.4%), whereas NKX2-1 expression was comparable in both primary tumors and brain metastases. Positive FOXA1 and NKX2-1 expression was associated with a gain or amplification in 34.6% and 28.6% of cases, respectively. The expression of NKX2-1 was associated with early stage and grade among the AC cases. In contrast, FOXA1 expression in SCC was associated with distant metastases as well as an unfavorable survival rate (P = 0.039). These results suggest that both FOXA1 and NKX2-1 may act as lineage-specific target genes within the 14q amplicon with opposite functions in lung cancer.

Journal ArticleDOI
TL;DR: The hypothesis that the prognostic relevance of lymph node metastases may lie in their ability to indicate that primary tumors are producing soluble factors that have the potential to promote metastasis at these distant sites is examined.
Abstract: Although tumor cells are found in the blood early after tumorigenesis, dissemination through the lymphatic system and in particular the formation of lymph node metastases has long been considered to be a driving force behind the formation of secondary tumors in distant vital organs Contemporary experimental observations and clinical trial results suggest that this may not be the case In this review we survey the evidence for both points of view, and examine the hypothesis that the prognostic relevance of lymph node metastases may lie in their ability to indicate that primary tumors are producing soluble factors that have the potential to promote metastasis at these distant sites, for example by releasing tumor cells from dormancy Furthermore, the interconnectivity between the lymphatic and blood circulatory systems underscores the relevance of the analysis of the properties of circulating and disseminated tumor cells for prognostic evaluation, patient stratification and understanding the biology of metastasis We therefore give an overview of the current state of the art in this field

Journal ArticleDOI
TL;DR: The properties of the microenvironment including metabolic and cytoprotective programs that ensure survival of disseminated tumor cells, blood vessel structure, and the hypoxia-normoxia switch are focused as well as intrinsic factors affecting the evolvement of novel tumor cell populations.
Abstract: The interrelating dynamics of the primary tumor cells and their surrounding microenvironment might determine phenotypic characteristics of disseminated tumor cells and contribute to cancer metastasis. Cytoprotective mechanisms (e.g., energy metabolism control, DNA damage response, global translation control and unfolded protein response) exert selective pressure in the tumor microenvironment. In particular, adaptation to hypoxia is vital for survival of malignant cells in the tumor and at distant sites such as the bone marrow. In addition to the stress response, the ability of tumor cells to undergo certain cellular re-differentiation programmes like the epithelial-mesenchymal transition (EMT), which is linked to cancer stemness, appears to be important for successful cancer cell spread. Here we will discuss the selection pressures that eventually lead to the formation of overt metastases. We will focus the properties of the microenvironment including (i) metabolic and cytoprotective programs that ensure survival of disseminated tumor cells, (ii) blood vessel structure, and (iii) the hypoxia-normoxia switch as well as intrinsic factors affecting the evolvement of novel tumor cell populations.

Journal ArticleDOI
31 Oct 2012-PLOS ONE
TL;DR: Clinical significance of loss at 11p15 in primary breast cancer (BC) and breast cancer brain metastases (BCBM) is investigated and it is found to be a marker for TNBC primary tumors and BCBM and PRKCDBP is a potential target gene in this locus.
Abstract: The occurrence of brain metastases among breast cancer patients is currently rising with approximately 20-25% incidence rates, underlining the importance of the identification of new therapeutic and prognostic markers. We have previously screened for new markers for brain metastasis by array CGH. We found that loss of 11p15 is common among these patients. In this study, we investigated the clinical significance of loss of 11p15 in primary breast cancer (BC) and breast cancer brain metastases (BCBM). 11p15 aberration patterns were assessed by allelic imbalance (AI) analysis in primary BC (n = 78), BCBM (n = 21) and metastases from other distant sites (n = 6) using six different markers. AI at 11p15 was significantly associated with BCBM (p = 0.002). Interestingly, a subgroup of primary BC with a later relapse to the brain had almost equally high AI rates as the BCBM cases. In primary BC, AI was statistically significantly associated with high grade, negative hormone receptor status, and triple-negative (TNBC) tumors. Gene expression profiling identified PRKCDBP in the 11p15 region to be significantly downregulated in both BCBM and primary BC with brain relapse compared to primary tumors without relapse or bone metastasis (fdr<0.05). qRT-PCR confirmed these results and methylation was shown to be a common way to silence this gene. In conclusion, we found loss at 11p15 to be a marker for TNBC primary tumors and BCBM and PRKCDBP to be a potential target gene in this locus.

Journal ArticleDOI
TL;DR: This work will focus on blood as the source of biomarker research and in particular comment on circulating tumor cells (CTCs) and circulating nucleic acids.
Abstract: The NIH Biomarkers Definition Working Group defined a biomarker as “a characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacological responses to a therapeutic intervention” (1). In lung cancer, an enormous research effort is underway related to biomarkers in airway epithelial cells, sputum, breath, urine and blood for early diagnosis or prediction of high risk. Here, we will focus on blood as the source of biomarker research and in particular comment on circulating tumor cells (CTCs) and circulating nucleic acids.

Journal ArticleDOI
TL;DR: This is a randomized, open-label, two arm phase III study to investigate the clinical efficacy of lapatinib, as a Her2-targeted therapy in initially HER2-negative metastatic breast cancer pts with HER2 -positive CTC at the time of distant disease.
Abstract: TPS1146 Background: HER2 status may change over the course of disease in breast cancer pts. Approx. 20-30% of pts with initially HER2-negative breast cancer have HER2-positive metastasis (Zidan et ...

Journal ArticleDOI
TL;DR: VEGFR2 germline polymorphisms predict tumor recurrence and OS in NSCLC and were a predictor for better OS in squamous cell carcinoma.
Abstract: VEGFR-2 gene displays several functional germline polymorphisms with impact on VEGFR-2 mediated angiogenesis. Our purpose was to evaluate VEGFR-2 polymorphisms as prognostic markers for tumor recurrence and overall survival (OS) in non-small-cell lung cancer (NSCLC). In total, 209 Caucasian patients who had been surgically treated for NSCLC between 1996 and 2010 were included in this study. Genotyping of peripheral blood cells was performed by TaqMan® genotyping assays or polymerase chain reaction for five VEGFR-2 polymorphisms. Chi- square test, Kaplan–Meier estimator, and Cox regression hazard model were used to assess the prognostic value of VEGFR-2 polymorphisms. VEGFR-2+4422 (AC)10–14 polymorphism was identified as a positive prognostic marker for time to metastasis (11/12 vs. 11/11 (AC) repeats: hazard ratio (HR), 0.28; 95% confidence interval (CI), 0.11–0.75; p = 0.012) and OS (11/12 vs. 11/11 (AC) repeats: HR, 0.41; 95% CI, 0.21–0.82; p = 0.012) in squamous cell carcinoma. For adenocarcinoma, VEGFR-2−906 C>T (C/T vs. CC: HR, 0.19; 95% CI, 0.43–0.82; p = 0.027) and VEGFR-2−271 G>A (G/A vs. G/G: HR, 0.25; 95% CI, 0.07–0.86; p = 0.027) predicted longer time to local recurrence and VEGFR-2−906 C>T was a predictor for better OS (T/T vs. C/C: HR, 0.28; 95% CI, 0.09–0.84; p = 0.024). VEGFR2 germline polymorphisms predict tumor recurrence and OS in NSCLC.

Journal ArticleDOI
TL;DR: In this paper, the role of placental growth factor (PlGF) and its receptor VEGFR-1 in tumor biology remain more elusive, and the authors determined mRNA expression levels of PlGF1-4 and of VEGfr-1 by QRT-PCR in human esophageal tumor tissue and investigated whether gene expression levels correlate with clinical data.
Abstract: Blocking angiogenesis by inhibiting VEGF represents an established therapeutic strategy in many cancers. The role of placental growth factor (PlGF) and of its receptor VEGFR-1 in tumor biology remain more elusive. Currently, humanized monoclonal antibodies against PlGF are studied in early phase clinical trials because PlGF inhibition blocked murine tumor growth and angiogenesis. In contrast to mice exclusively expressing one PlGF isoform (PlGF-2), humans can produce four PlGF isoforms (PlGF1-4). Surprisingly nothing is yet known about expression of all four PlGF isoforms in human cancer, because until now mostly total PlGF levels or PlGF-1/2 were analyzed without discriminating further. In this study we determined mRNA expression levels of PlGF1-4 and of VEGFR-1 by QRT-PCR in human esophageal tumor tissue and investigated whether gene expression levels correlate with clinical data. PlGF-1 and -2 were expressed in virtually all analyzable tumors, whereas PlGF-3 and -4 were present in tumors of 59 and 74 % of patients, respectively. MRNA Expression levels of all four splice variants correlated with each other. In contrast, PlGF-1 and -2 mRNA expression was lower in esophageal control tissue and PlGF-3 and -4 mRNA were undetectable. VEGFR-1 was expressed by more than 80 % of patients. Interestingly, VEGFR-1 expression levels significantly correlate with presence of disseminated tumor cells (DTCs) in bone marrow. Patients with DTCs exhibit lower VEGFR-1 mRNA expression than patients without DTCs. Pending validation in other types of cancer, expression levels of VEGFR-1 might be useful as surrogate marker for DTCs.




Journal ArticleDOI
TL;DR: The Her2-status of CTC was prospectively evaluated in the German multicenter SUCCESS B study and the results confirmed that CTC-positivity is low compared to other breast cancer patients receiving adjuvant treatment with Trastuzumab.
Abstract: 10540 Background: Recent reports showed a discrepancy in the Her2-status of metastases or minimal residual disease in blood and bone marrow compared to the primary tumor in patients with breast can...

Book ChapterDOI
TL;DR: A robust reliable system for the immunochemical detection of individual micrometastatic tumour cells from the BM aspirates of patients with solid epithelial tumours, based on the binding of antibody to cytokeratin proteins is described.
Abstract: Detection of micrometastases in the bone marrow (BM) of cancer patients may be a helpful method for early detection of relapse. The diverse methodology employed across different laboratories, however, renders comparison of results difficult. This chapter describes a robust reliable system for the immunochemical detection of individual micrometastatic tumour cells from the BM aspirates of patients with solid epithelial tumours, based on the binding of antibody to cytokeratin proteins.