LASER-INDUCED M1 RESONANCE SPECTROSCOPY OF THE 1S2P3P1-3P2 FINE-STRUCTURE OF F-19(7+)

We report the first observation of a laser-induced M1 transition in a fast beam. This new method has been applied to a measurement of the F=12-32 and F=32-52 hyperfine components of the 1s2p P13-P23 fine-structure interval in heliumlike fluorine. The results are 953.60(3) and 961.77(3) cm -1, respectively. From these we extract the fine-structure splitting Δ12=957.88(3) cm-1. © 1981 The American Physical Society

Catch and release: Rare cell analysis from a functionalised medical wire

Enumeration and especially molecular characterization of circulating tumour cells (CTCs) holds great promise for cancer management. We tested a modified type of an in vivo enrichment device (Catch&Release) for its ability to bind and detach cancer cells for the purpose of single-cell molecular downstream analysis in vitro. The evaluation showed that single-cell analysis using array comparative genome hybridization (array-CGH) and next generation sequencing (NGS) is feasible. We found array-CGH to be less noisy when whole genome amplification (WGA) was performed with Ampli1 as compared to GenomePlex (DLRS values 0.65 vs. 1.39). Moreover, Ampli1-processed cells allowed detection of smaller aberrations (median 14.0 vs. 49.9 Mb). Single-cell NGS data obtained from Ampli1-processed samples showed the expected non-synonymous mutations (deletion/SNP) according to bulk DNA. We conclude that clinical application of this refined in vivo enrichment device allows CTC enumeration and characterization, thus, representing a promising tool for personalized medicine

In Vivo Detection of Circulating Tumor Cells in High-Risk Non-Metastatic Prostate Cancer Patients Undergoing Radiotherapy

High-risk non-metastatic prostate cancer (PCa) has the potential to progress into lethal disease. Treatment options are manifold but, given a lack of surrogate biomarkers, it remains unclear which treatment offers the best results. Several studies have reported circulating tumor cells (CTCs) to be a prognostic biomarker in metastatic PCa. However, few reports on CTCs in high-risk non-metastatic PCa are available. Herein, we evaluated CTC detection in high-risk non-metastatic PCa patients using the in vivo CellCollector CANCER01 (DC01) and CellSearch system. CTC counts were analyzed and compared before and after radiotherapy (two sampling time points) in 51 high-risk non-metastatic PCa patients and were further compared according to isolation technique; further, CTC counts were correlated to clinical features. Use of DC01 resulted in a significantly higher percentage of CTC-positive samples compared to CellSearch (33.7% vs. 18.6%; p = 0.024) and yielded significantly higher CTC numbers (range: 0–15 vs. 0–5; p = 0.006). Matched pair analysis of samples between two sampling time points showed no difference in CTC counts determined by both techniques. CTC counts were not correlated with clinicopathological features. In vivo enrichment using DC01 has the potential to detect CTC at a higher efficiency compared to CellSearch, suggesting that CTC is a suitable biomarker in high-risk non-metastatic PCa

Multiplex Gene Expression Profiling of In Vivo Isolated Circulating Tumor Cells in High-Risk Prostate Cancer Patients

International audienceBACKGROUND: Molecular characterization of circulating tumor cells (CTCs) is important for selecting patients for targeted treatments. We present, for the first time, results on gene expression profiling of CTCs isolated in vivo from high-risk prostate cancer (PCa) patients compared with CTC detected by 3 protein-based assays-CellSearch\textregistered, PSA-EPISPOT, and immunofluorescence of CellCollector\textregistered in vivo-captured CTCs-using the same blood draw. METHODS: EpCAM-positive CTCs were isolated in vivo using the CellCollector from 108 high-risk PCa patients and 36 healthy volunteers. For 27 patients, samples were available before and after treatment. We developed highly sensitive multiplex RT-qPCR assays for 14 genes (KRT19, EpCAM, CDH1, HMBS, PSCA, ALDH1A1, PROM1, HPRT1, TWIST1, VIM, CDH2, B2M, PLS3, and PSA), including epithelial markers, stem cell markers, and epithelial-to-mesenchymal-transition (EMT) markers. RESULTS: We observed high heterogeneity in gene expression in the captured CTCs for each patient. At least 1 marker was detected in 74 of 105 patients (70.5%), 2 markers in 45 of 105 (40.9%), and 3 markers in 16 of 105 (15.2%). Epithelial markers were detected in 31 of 105 (29.5%) patients, EMT markers in 46 of 105 (43.8%), and stem cell markers in 15 of 105 (14.3%) patients. EMT-marker positivity was very low before therapy (2 of 27, 7.4%), but it increased after therapy (17 of 27, 63.0%), whereas epithelial markers tended to decrease after therapy (2 of 27, 7.4%) compared with before therapy (13 of 27, 48.1%). At least 2 markers were expressed in 40.9% of patients, whereas the positivity was 19.6% for CellSearch, 38.1% for EPISPOT, and 43.8% for CellCollector-based IF-staining. CONCLUSIONS: The combination of in vivo CTC isolation with downstream RNA analysis is highly promising as a high-throughput, specific, and ultrasensitive approach for multiplex liquid biopsy-based molecular diagnostics

A Comprehensive Molecular Analysis of in Vivo Isolated EpCAM-Positive Circulating Tumor Cells in Breast Cancer

BACKGROUND: Circulating tumor cell (CTC) analysis is highly promising for liquid biopsy-based molecular diagnostics. We undertook a comprehensive molecular analysis of in vivo isolated CTCs in breast cancer (BrCa). METHODS: In vivo isolated CTCs from 42 patients with early and 23 patients with metastatic breast cancer (MBC) were prospectively collected and analyzed for gene expression, DNA mutations, and DNA methylation before and after treatment. 19 healthy donor (HD) samples were analyzed as a control group. In identical blood draws, CTCs were enumerated using CellSearch (R) and characterized by direct IF staining. RESULTS: All 19 HD samples were negative for CK8, CK18, CK19, ERBB2, TWIST1, VEGF, ESR1, PR, and EGFR expression, while CD44, CD24, ALDH1, VIM, and CDH2 expression was normalized to B2M (reference gene). At least one gene was expressed in 23/42 (54.8%) and 8/13 (61.5%) CTCs in early BrCa before and after therapy, and in 20/23 (87.0%) and 5/7 (71.4%) MBC before and after the first cycle of therapy. PIK3CA mutations were detected in 11/42 (26.2%) and 3/13 (23.1%) in vivo isolated CTCs in early BrCa before and after therapy, and in 11/23 (47.8%) and 2/7 (28.6%) MBC, respectively. ESR1 methylation was detected in 5/32 (15.7%) and 1/10 (10.0%) CTCs in early BrCa before and after therapy, and in 3/15(20.0%) MBC before the first line of therapy. The comprehensive molecular analysis of CTC revealed a higher sensitivity in relation to CellSearch or IF staining when based on creatine kinase selection. CONCLUSIONS: In vivo-CTC isolation in combination with a comprehensive molecular analysis at the gene expression, DNA mutation, and DNA methylation level comprises a highly powerful approach for molecular diagnostic applications using CTCs

Characterization of circulating breast cancer cells with tumorigenic and metastatic capacity

Functional studies giving insight into the biology of circulating tumor cells (CTCs) remain scarce due to the low frequency ofCTCs and lack of appropriate models. Here, we describe the characterization of a novelCTC-derived breast cancer cell line, designatedCTC-ITB-01, established from a patient with metastatic estrogen receptor-positive (ER+) breast cancer, resistant to endocrine therapy.CTC-ITB-01 remainedER(+)in culture, and copy number alteration (CNA) profiling showed high concordance betweenCTC-ITB-01 andCTCs originally present in the patient with cancer at the time point of blood draw.RNA-sequencing data indicate thatCTC-ITB-01 has a predominantly epithelial expression signature. Primary tumor and metastasis formation in an intraductalPDXmouse model mirrored the clinical progression ofER(+)breast cancer. DownstreamERsignaling was constitutively active inCTC-ITB-01 independent of ligand availability, and theCDK4/6 inhibitor Palbociclib strongly inhibitedCTC-ITB-01 growth. Thus, we established a functional model that opens a new avenue to studyCTCbiology

Characterization of circulating breast cancer cells with tumorigenic and metastatic capacity

Functional studies giving insight into the biology of circulating tumor cells (CTCs) remain scarce due to the low frequency ofCTCs and lack of appropriate models. Here, we describe the characterization of a novelCTC-derived breast cancer cell line, designatedCTC-ITB-01, established from a patient with metastatic estrogen receptor-positive (ER+) breast cancer, resistant to endocrine therapy.CTC-ITB-01 remainedER(+)in culture, and copy number alteration (CNA) profiling showed high concordance betweenCTC-ITB-01 andCTCs originally present in the patient with cancer at the time point of blood draw.RNA-sequencing data indicate thatCTC-ITB-01 has a predominantly epithelial expression signature. Primary tumor and metastasis formation in an intraductalPDXmouse model mirrored the clinical progression ofER(+)breast cancer. DownstreamERsignaling was constitutively active inCTC-ITB-01 independent of ligand availability, and theCDK4/6 inhibitor Palbociclib strongly inhibitedCTC-ITB-01 growth. Thus, we established a functional model that opens a new avenue to studyCTCbiology