mRNA expression profiles in circulating tumor cells of metastatic colorectal cancer patients

The molecular characterization of circulating tumor cells (CTCs) is a promising tool for the repeated and non-invasive evaluation of predictive and prognostic factors. Challenges associated with CTC characterization using the only FDA approved method for CTC enumeration, the CellSearch technique, include the presence of an excess of leukocytes in CTC-enriched blood fractions. Here we aimed to identify colorectal tumor-specific gene expression levels in the blood of patients with and without detectable CTCs according to CellSearch criteria. Materials and methods: Blood of 30 healthy donors (HDs) and 142 metastatic colorectal cancer (mCRC) patients was subjected to CellSearch CTC enumeration and isolation. In all samples, 95 mRNAs were measured by reverse transcriptase quantitative PCR (RT-qPCR). HD blood samples and patient samples with three or more CTCs were compared to identify CTC-specific mRNAs. Patient samples without detectable CTCs were separately analyzed. Results: Thirty-four CTC-specific mRNAs were higher expressed in patients with ≥3 CTCs compared with HDs (Mann-Whitney U-test P<0.05). Among patients without detectable CTCs, a HD-unlike subgroup was identified which could be distinguished from HDs by the expression of epithelial genes such as KRT19, KRT20 and AGR2. Also, in an independent patient set, a similar HD-unlike group could be identified among the patients without detectable CTCs according to the CellSearch system. Conclusion: Extensive molecular characterization of colorectal CTCs is feasible and a subgroup of patients without detectable CTCs according to CellSearch criteria bears circulating tumor load, which may have clinical consequences. This CTC-specific gene panel for mCRC patients may enable the exploration of CTC characterization as a novel means to further individualize cancer treatment

Molecular characteristics of circulating tumor cells resemble the liver metastasis more closely than the primary tumor in metastatic colorectal cancer

Background: CTCs are a promising alternative for metastatic tissue biopsies for use in precision medicine approaches. We investigated to what extent the molecular characteristics of circula

Prognostic value of circulating tumour cells for early recurrence after resection of colorectal liver metastases

Background: Despite good outcomes for many, a substantial group of patients undergoing metastasectomy for isolated liver metastases from colorectal cancer (CRC) experience early recurrence. We have investigated whether circulating tumour cell (CTC) detection can identify patients developing disease recurrence within 1 year after liver metastasectomy. Methods: In CRC patients undergoing liver metastasectomy, 30 ml peripheral blood was withdrawn preoperatively. CTCs were detected by the CellSearch system after a density-gradient-based enrichment step. Results: One hundred and seventy-three samples from 151 individual patients were analysed. In 75 samples (43%), CTCs were detected, 16% had >= 3 CTCs/7.5 ml of blood. Eighty-two patients (47%) experienced early disease recurrence (= 3 CTCs/7.5 ml of blood) (50% vs 47%). Also disease-free and overall survival were similar between patients with or without CTCs. Conclusions: The presence of CTCs in preoperative peripheral blood samples does not identify patients at risk for early disease recurrence after curative resection of colorectal liver metastases. Other parameters are needed to better identify patients at high risk to relapse after liver metastasectomy for CRC

mRNA expression profiles in circulating tumor cells of metastatic colorectal cancer patients

Introduction: The molecular characterization of circulating tumor cells (CTCs) is a promising tool for the repeated and non-invasive evaluation of predictive and prognostic factors. Challenges associated with CTC characterization using the only FDA approved method for CTC enumeration, the CellSearch technique, include the presence of an excess of leukocytes in CTC-enriched blood fractions. Here we aimed to identify colorectal tumor-specific gene expression levels in the blood of patients with and without detectable CTCs according to CellSearch criteria. Materials and methods: Blood of 30 healthy donors (HDs) and 142 metastatic colorectal cancer (mCRC) patients was subjected to CellSearch CTC enumeration and isolation. In all samples, 95 mRNAs were measured by reverse transcriptase quantitative PCR (RT-qPCR). HD blood samples and patient samples with three or more CTCs were compared to identify CTC-specific mRNAs. Patient samples without detectable CTCs were separately analyzed. Results: Thirty-four CTC-specific mRNAs were higher expressed in patients with >= 3 CTCs compared with HDs (Mann Whitney U-test P < 0.05). Among patients without detectable CTCs, a HD-unlike subgroup was identified which could be distinguished from HDs by the expression of epithelial genes such as KRT19, KRT20 and AGR2. Also, in an independent patient set, a similar HD-unlike group could be identified among the patients without detectable CTCs according to the CellSearch system. Conclusion: Extensive molecular characterization of colorectal CTCs is feasible and a subgroup of patients without detectable CTCs according to CellSearch criteria bears circulating tumor load, which may have clinical consequences. This CTC-specific gene panel for mCRC patients may enable the exploration of CTC characterization as a novel means to further individualize cancer treatment. (C) 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved

Molecular characteristics of circulating tumor cells resemble the liver metastasis more closely than the primary tumor in metastatic colorectal cancer

BACKGROUND: CTCs are a promising alternative for metastatic tissue biopsies for use in precision medicine approaches. We investigated to what extent the molecular characteristics of circulating tumor cells (CTCs) resemble the liver metastasis and/or the primary tumor from patients with metastatic colorectal cancer (mCRC). RESULTS: The CTC profiles were concordant with the liver metastasis in 17/23 patients (74%) and with the primary tumor in 13 patients (57%). The CTCs better resembled the liver metastasis in 13 patients (57%), and the primary tumor in five patients (22%). The strength of the correlations was not associated with clinical parameters. Nine genes (CDH1, CDH17, CDX1, CEACAM5, FABP1, FCGBP, IGFBP3, IGFBP4, and MAPT) displayed significant differential expressions, all of which were downregulated, in CTCs compared to the tissues in the 23 patients. PATIENTS AND METHODS: Patients were retrospectively selected from a prospective study. Using the CellSearch System, CTCs were enumerated and isolated just prior to liver metastasectomy. A panel of 25 CTC-specific genes was measured by RT-qPCR in matching CTCs, primary tumors, and liver metastases. Spearman correlation coefficients were calculated and considered as continuous variables with r=1 representing absolute concordance and r= -1 representing absolute discordance. A cut-off of r>0.1 was applied in order to consider profiles to be concordant. CONCLUSIONS: In the majority of the patients, CTCs reflected the molecular characteristics of metastatic cells better than the primary tumors. Genes involved in cell adhesion and epithelial-to-mesenchymal transition were downregulated in the CTCs. Our results support the use of CTC characterization as a liquid biopsy for precision medicine

Clinical impact of five large-scale screening projects for chronic hepatitis B in Chinese migrants in the Netherlands

BACKGROUND & AIMS: In low-endemic countries it is debated whether first-generation migrants should be screened for chronic hepatitis B infection. We describe the clinical impact of five large-scale Dutch screening projects for hepatitis B in first-generation Chinese migrants. METHODS: Between 2009 and 2013 five independent outreach screening projects for hepatitis B targeting first-generation Chinese migrants were conducted in five main Dutch regions. To explore the relevance of our screening we defined clinical impact as the presence of an indication for: (i) antiviral therapy, (ii) strict follow-up because of high hepatitis B DNA levels and/or (iii) surveillance for hepatocellular carcinoma. RESULTS: In total, 4423 persons participated in the projects of whom 6.0% (n = 264) were HBsAg positive. One hundred and twenty-nine newly diagnosed HBsAg-positive patients were analysed in specialist care. Among these patients prevalence of cirrhosis was 6.9% and antiviral therapy for hepatitis B was started in 32 patients (25%). In patients without a treatment indication, strict follow-up because of high hepatitis B DNA levels and/or surveillance for hepatocellular carcinoma was considered indicated in 64 patients (50%). CONCLUSIONS: In our screening project in first-generation Chinese migrants, antiviral treatment, strict follow-up because of high hepatitis B DNA levels and/or surveillance for hepatocellular carcinoma were considered indicated in three of four analysed HBsAg-positive patients. These data show that detection of hepatitis B in Chinese migrants can have considerable impact on patient care