Increase in number of circulating disseminated epithelial cells after surgery for non-small cell lung cancer monitored by MAINTRAC(R) is a predictor for relapse: A preliminary report

Heterogeneity in Circulating Tumor Cells: The Relevance of the Stem-Cell Subset

The release of circulating tumor cells (CTCs) into vasculature is an early event in the metastatic process. The analysis of CTCs in patients has recently received widespread attention because of its clinical implications, particularly for precision medicine. Accumulated evidence documents a large heterogeneity in CTCs across patients. Currently, the most accepted view is that tumor cells with an intermediate phenotype between epithelial and mesenchymal have the highest plasticity. Indeed, the existence of a meta-stable or partial epithelial–mesenchymal transition (EMT) cell state, with both epithelial and mesenchymal features, can be easily reconciled with the concept of a highly plastic stem-like state. A close connection between EMT and cancer stem cells (CSC) traits, with enhanced metastatic competence and drug resistance, has also been described. Accordingly, a subset of CTCs consisting of CSC, present a stemness profile, are able to survive chemotherapy, and generate metastases after xenotransplantation in immunodeficient mice. In the present review, we discuss the current evidence connecting CTCs, EMT, and stemness. An improved understanding of the CTC/EMT/CSC connections may uncover novel therapeutic targets, irrespective of the tumor type, since most cancers seem to harbor a pool of CSCs, and disclose important mechanisms underlying tumorigenicity.

The Value of Monitoring the Behavior of Circulating Tumor Cells at the End of Endocrine Therapy in Breast Cancer Patients

After five years of endocrine therapy, patients with ER+ (estrogen receptor positive) breast cancer face the question of the benefit of further treatment. Ten years of endocrine therapy has been demonstrated to improve survival compared to five years. However, the individual benefit of continuation remains unclear. Therefore, markers for predicting benefit from endocrine treatment and extended endocrine treatment are desperately needed. In this study the dynamics over time of the tumor cells circulating in peripheral blood of patients, circulating tumor cells/ circulating epithelial tumor cells (CTC/CETC), as the systemic part of the tumor were investigated in 36 patients with ER+ primary breast cancer. CTC/CETCs were monitored serially during and after endocrine therapy. After termination of endocrine therapy 12 patients showed an increase in CTC/CETCs, with 8 of 12 suffering relapse. No change or a reduction was observed in 24 patients, with 2 of 24 suffering relapse. Initial tumor size was marginally prognostic (p = 0.053) but not nodal status nor the mere number of CTC/CETCs. Only the trajectory of CTC/CETCs was a statistically significant predictor of relapse free survival (increasing cell numbers: mean = 940 days vs. stable/decreasing cell numbers mean not reached). Individual cases demonstrated that an increase of CTC/CETCs after discontinuation of tamoxifen therapy could be stopped by resuming the endocrine therapy.

The Present and Future of Liquid Biopsies in Non-Small Cell Lung Cancer: Combining Four Biosources for Diagnosis, Prognosis, Prediction, and Disease Monitoring

PURPOSE OF REVIEW

Liquid biopsies have potential as tools for diagnosis, prognosis, and prediction of response to therapy. Herein, we will extensively review four liquid biosources, tumor-educated platelets (TEPs), cell-free DNA (cfDNA), circulating tumor cells (CTCs), and extracellular vesicles (EVs) and we will clarify their optimal application in non-small cell lung cancer (NSCLC) diagnosis and therapy.

RECENT FINDINGS

Liquid biopsies are a minimally invasive alternative to tissue biopsies-especially important in NSCLC patients-since tumor tissue is often unavailable or insufficient for complete genetic analysis. The main advantages of liquid biopsies include the possibility for repeated sampling, the lower cost, and the fact that they can reflect the complete molecular status of the patient better than a single-site biopsy. This is specifically important for lung adenocarcinoma patients since the detection of specific genetic alterations can predict response to targeted therapies. Molecular analysis is currently cardinal for therapy decision-making and disease monitoring in lung cancer patients. Liquid biopsies can make easier our daily clinical practice and if prospectively tested and validated may serve as a means for lung cancer early detection.

The role of liquid biopsy in predicting post-operative recurrence of non-small cell lung cancer

Background

Radical resection is the cornerstone for patients with early stage of non-small cell lung cancer (NSCLC). However, fatal disease recurs in about 30-70% of resected cases. The circulating tumor cells (CTCs) is one of the main causes of recurrence of cancer. Circulating tumor DNA (ctDNA) is also a potential predictive biomarker of recurrence in patients with early stage NSCLC. A meta-analysis was conducted to identify the prognostic value of the CTCs and ctDNA in predicting the disease recurrence after surgery of NSCLC patients.

Methods

Electronic databases were comprehensively searched for eligible studies. A random effects model was used. The primary endpoint was the hazards ratio (HR) for the disease-free survival (DFS) between CTCs/ctDNA positive and negative groups. The relative risks (RR) of one and two-year recurrence rate between CTCs/ctDNA positive and negative groups were also calculated.

Results

A total of 5 studies involving 351 patients were included, in which 3 were studies on CTCs and 2 were ctDNA. Our result revealed that positive peripheral blood CTCs (HR, 3.37; 95% CI: 2.28-4.96; P<0.001) and ctDNA (HR, 8.15; 95% CI: 2.11-31.50; P=0.002) indicated poor prognosis for DFS. One (68% vs. 18.2%; RR 3.28; P<0.001) and two (76% vs. 44%; RR 1.80; P=0.06) years recurrence rate were higher in CTCs positive group compared with the negative group, respectively. The same result was also observed in ctDNA positive versus negative groups of 1 (77.9% vs. 8.3%; RR 9.05; P=0.001) and 2 (85.6% vs. 8.3%; RR 9.63; P<0.001) years recurrence rate.

Conclusions

Both postoperative CTCs and ctDNA are promising predictive biomarkers of early tumor recurrence in NSCLC patients. In addition, detection based on ctDNA seems to be more sensitive than CTCs.

Detection of Circulating Tumor Cells Using Microfluidics

Metastasis is the main cause of death in cancer patients worldwide. During metastasis, cancer cells detach from the primary tumor and invade distant tissue. The cells that undergo this process are called circulating tumor cells (CTCs). Studies show that the number of CTCs in the peripheral blood can predict progression-free survival and overall survival and can be informative concerning the efficacy of treatment. Research is now concentrated on developing devices that can detect CTCs in the blood of cancer patients with improved sensitivity and specificity that can lead to improved clinical evaluation. This review focuses on devices that detect and capture CTCs using different cell properties (surface markers, size, deformability, electrical properties, etc.). We also discuss the process of tumor cell dissemination, the biology of CTCs, epithelial-mesenchymal transition (EMT), and several challenges and clinical applications of CTC detection.

Embedded Disposable Functionalized Electrochemical Biosensor with a 3D-Printed Flow Cell for Detection of Hepatic Oval Cells (HOCs)

Hepatic oval cells (HOCs) are considered the progeny of the intrahepatic stem cells that are found in a small population in the liver after hepatocyte proliferation is inhibited. Due to their small number, isolation and capture of these cells constitute a challenging task for immunosensor technology. This work describes the development of a 3D-printed continuous flow system and exploits disposable screen-printed electrodes for the rapid detection of HOCs that over-express the OV6 marker on their membrane. Multiwall carbon nanotube (MWCNT) electrodes have a chitosan film that serves as a scaffold for the immobilization of oval cell marker antibodies (anti-OV6-Ab), which enhance the sensitivity of the biomarker and makes the designed sensor specific for oval cells. The developed sensor can be easily embedded into the 3D-printed flow cell to allow cells to be exposed continuously to the functionalized surface. The continuous flow is intended to increase capture of most of the target cells in the specimen. Contact angle measurements were performed to characterize the nature and quality of the modified sensor surface, and electrochemical measurements (cyclic voltammetry (CV) and square wave voltammetry (SWV)) were performed to confirm the efficiency and selectivity of the fabricated sensor to detect HOCs. The proposed method is valuable for capturing rare cells and could provide an effective tool for cancer diagnosis and detection.

Circulating epithelial cells in patients with thyroid carcinoma

Goal: To investigate whether circulating epithelial cells (CEC) recognized via the epithelial cell adhesion molecule (EpCAM) can be identified in the blood of patients with thyroid carcinoma, given that CEC have already been detected in other types of carcinoma and are considered a potential marker of tumour dissemination. Patients, methods: Blood samples of patients with active differentiated thyroid carcinoma (DTC) (n = 50) were compared to samples of patients with: a) recent surgical excision of a thyroid carcinoma (postOP-DTC) (n = 16); b) athyreotic, tumour-free status after radioiodine ablation (AT-DTC) (n= 33); and c) benign thyroid diseases (BTD) (n = 51). Samples of volunteers with normal thyroid parameters (NT) (n = 12) were also investigated. Cells from EDTAblood were subjected to erythrocyte lysis, isolated by centrifugation, and incubated with a fluorescence-labeled antibody against EpCAM. The numbers of vital cells were counted via fluorescence microscopy. Results: CEC were identified in all groups, with the postOP-DTC group showing the highest mean CEC numbers of all groups. The DTC group had significantly higher CEC numbers than the NT group, and numerically higher numbers than the other groups, although not reaching statistical significance. Within the DTC group there was a correlation between levels of serum thyroglobulin and numbers of CEC (r = 0.409, p = 0.003). Conclusions: High CEC numbers were not specific to thyroid carcinoma. The methodology used here, based on a single measurement does not allow to identify severe forms of DTC, emphasizing the need of longitudinal measurements throughout therapy. Detection and characterization of tumour thyroid cells in circulation should be based on additiona l consideration of tissue-specific characteristics.

Blood-based tumor biomarkers in lung cancer for detection and treatment

The therapeutic landscape of lung cancer has expanded significantly over the past decade. Advancements in molecularly targeted therapies, strategies to discover and treat resistance mutations, and development of personalized cancer treatments in the context of tumor heterogeneity and dynamic tumor biology have made it imperative to obtain tumor samples on several different occasions through the course of patient treatment. While this approach is critical to the delivery of optimal cancer treatment, it is fraught with a number of barriers including the need for invasive procedures with associated complications, access to limited amount of tissue, logistical delays in obtaining the biopsy, high healthcare cost, and in many cases inability to obtain tissue because of technically difficult location of the tumor. Given multiple limitations of obtaining tissue samples, the use of blood-based biomarkers ("liquid biopsies") may enable earlier diagnosis of cancer, lower costs by avoiding complex invasive procedures, tailoring molecular targeted treatments, improving patient convenience, and ultimately supplement clinical oncologic decision-making. In this paper, we review various blood-based biomarkers including circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), tumor derived exosomes, tumor educated platelets (TEPs), and microRNA; and highlight current evidence for their use in detection and treatment of lung cancer.

Establishment and Application of Prostate Cancer Circulating Tumor Cells in the Era of Precision Medicine

Prostate cancer (PC) is the second most common cancer in men and is the fifth leading cause of cancer-related deaths worldwide. Additionally, there is concern for overdiagnosis and overtreatment of PC. Thus, selection of an appropriate candidate for active surveillance as well as more accurate and less invasive tools for monitoring advanced PC is required. Circulating tumor cells (CTCs) have emerged as a liquid biopsy tool; there have been several reports on its role, technologies, and applications to various cancers, including PC. Liquid biopsy using CTCs has been gaining attention as a minimal invasive tool for investigation of biomarkers and for prognosis and assessment of response to therapies in patients with PC. Because of the lower invasiveness of liquid biopsy using CTCs, it can be performed more frequently; accordingly, personalized disease status can be successively determined at serial time points. CTC analysis enables detection of genomic alterations, which is drug-targetable, and it is a potential tool for monitoring response to therapeutic agents in patients with PC. This review focuses on the characteristics, technologies for analysis, and advantages and disadvantages of CTCs as a liquid biopsy tool and their application in PC. Finally, we propose future directions of CTCs.

Detection of circulating tumor cells using oHSV1-hTERT-GFP in lung cancer

BACKGROUND

This study was conducted to evaluate the clinical utility of the oHSV1-hTERT-GFP circulating tumor cell (CTC) detection method in the peripheral blood of patients with lung cancer by comparing its sensitivity to the CellSearch CTC detection method.

METHODS

The oHSV1-hTERT-GFP and CellSearch CTC detection methods were compared using peripheral blood samples of patients pathologically diagnosed with lung cancer.

RESULTS

A total of 240 patients with lung cancer were recruited, including 89 patients who were newly diagnosed and 151 patients who had previously received treatment. Sixty-six newly diagnosed patients were evaluated using both methods. The CTC detection rates were 71.2% and 33.3% using the oHSV1-hTERT-GFP and CellSearch methods, respectively; this difference was statistically significant (P = 0.000). Among the entire cohort (n = 240), the CTC detection rate using the oHSV1-hTERT-GFP method was 76.3%, with a CTC count of 0-81. The CTC detection rates were 76.7%, 68.9%, and 76.3% in patients with squamous cell carcinoma, adenocarcinoma, and small cell lung cancer, respectively. There was no statistically significant difference in the CTC detection rates between these different pathological subtypes (P = 0.738). The CTC detection rates of 79.8% and 74.4% in patients with stage I-III and IV lung cancer, respectively, were not significantly different (P = 0.427).

CONCLUSION

The oHSV1-hTERT-GFP method is highly effective for detecting CTCs in patients with lung cancer, independent of pathological type and disease stage, and is ideal for large-scale clinical applications.

Frequency and clinical impact of preoperative circulating tumor cells in resectable non-metastatic lung adenocarcinomas

OBJECTIVES

Despite successful surgery, 30-50% of patients with resectable non-small cell lung cancer develop tumor recurrence within 5 years of surgery.

MATERIALS AND METHODS

In this prospective study, we performed CTC enumerations in 40 patients with non-metastatic lung adenocarcinoma (NMLA) using a size-based microfilter. Additionally, cfDNA isolated from plasma was analyzed in 35 out of 40 patients.

RESULTS

CTCs were identified in 15 out of 40 patients (37.5%) with a range of 1-44 cells, whereas mutated cfDNA was only detected in 3 out of 35 patients (8.6%). Disease-free survival (DFS) was significantly associated with CTC positivity (log-rank p=0.025), grading (log-rank p=0.019), tumor stage (log-rank p=0.025) and lymph node status (log-rank p=0.029). Multivariate analysis, including tumor stage and grading, showed that CTC positivity (p=0.006), grading (0.039) and tumor stage (p=0.022) were independently associated with DFS.

CONCLUSION

Our study found that microfilter-based CTC enumeration in NMLA patients is an independent predictor of worse DFS. The used NGS-based cfDNA characterization had limited sensitivity to be clinically informative in our study cohort. CTC assessment before surgery can thus identify NMLA patients at high risk of disease recurrence.

Clinical utility of circulating tumor cells in patients with non-small-cell lung cancer

Several different studies have addressed the role of the circulating tumor cells (CTC) in non-small-cell lung cancer (NSCLC). In particular, the potential of CTC analysis in the early diagnosis of NSCLC and in the prediction of the outcome of patients with early and advanced NSCLC have been explored. A major limit of these studies is that they used different techniques for CTC isolation and enumeration, they employed different thresholds to discriminate between high- and low-risk patients, and they enrolled heterogeneous and often small cohort of patients. Nevertheless, the results of many studies are concordant in indicating a correlation between high CTC count and poor prognosis in both early and advanced NSCLC. The reduction of CTC number following treatment might also represent an important indicator of sensitivity to therapy in patients with metastatic disease. Preliminary data also suggest the potential for CTC analysis in the early diagnosis of NSCLC in high-risk individuals. However, these findings need to be confirmed in large prospective trials in order to be transferred to the clinical practice. The molecular profiling of single CTC in NSCLC might provide important information on tumor biology and on the mechanisms involved in tumor dissemination and in acquired resistance to targeted therapies. In this respect, xenografts derived from CTC might represent a valuable tool to investigate these phenomena and to develop novel therapeutic strategies.

Isolation of circulating tumor cells in pancreatic cancer patients by immunocytochemical assay

BACKGROUND

The patients diagnosed with pancreatic cancer have the possibilities of getting the cancer again even after resection. The tumor cells identified from blood can be related to different stages of tumor.

METHODS

In this study, we used an immunoassay to detect circulating tumor cells in blood and bone marrow samples. About 120 patients' blood and bone marrow samples were used in this study along with controls. The presence of tumor cells was evaluated with different stages of cancer classified by UICC. The survival rate at each stages of tumor was also analyzed.

RESULTS

The tumor cells were isolated both in blood (29%) and bone marrow samples (25%). The prevalence of tumor cells increased with increase in stages of tumor in blood samples.

CONCLUSION

The survival of the patients considerably related to different stages of tumor but it cannot be taken a parameter alone for the patients' survival.

[Diagnostic Value of Folate Receptor-positive Circulating Tumor Cell in Lung Cancer: A Pilot Study]

背景与目的

评价一种通过叶酸受体(folate receptor, FR)检测循环肿瘤细胞(circulating tumor cell, CTC)的方法用于肺癌临床诊断的实用性和可行性及进一步探究CTC在肺癌术后复发的预测价值。

方法

通过免疫磁珠负向富集方法从3 mL外周血中捕获循环肿瘤细胞，再用肿瘤特异性叶酸配体-寡核苷酸偶和物标记捕获的循环肿瘤细胞，洗去没有结合的偶和物后，洗脱下特异性结合的偶合物的寡核苷酸用于定量PCR扩增分析。

结果

97例肺癌患者的CTC水平高于肺部良性疾病患者(P < 0.001)。本检测方法以8.7 Folate Units/3 mL为cutoff值，结果显示靶向PCR法对肺癌的检测灵敏度为82.5%，特异性为72.2%，特别是在Ⅰ期肺癌灵敏度达到86.8%。与其他肿瘤标志物(NSE、CEA、CYFRA21-1)比较，CTC对肺癌及Ⅰ期肺癌具有较高的诊断准确性(0.859; 95%CI: 0.779-0.939)和(0.912; 95%CI: 0.829-0.994)。5例肺癌患者术后2周内CTC水平高于cutoff值。

结论

叶酸受体阳性循环肿瘤细胞可以应用于肺癌的临床诊断，即使是对早期非小细胞肺癌(non-small cell lung cancer, NSCLC)的诊断。

Fourier Ptychographic Microscopy for Rapid, High-Resolution Imaging of Circulating Tumor Cells Enriched by Microfiltration

Examining the hematogenous compartment for evidence of metastasis has increased significantly within the oncology research community in recent years, due to the development of technologies aimed at the enrichment of circulating tumor cells (CTCs), the subpopulation of primary tumor cells that gain access to the circulatory system and are responsible for colonization at distant sites. In contrast to other technologies, filtration-based CTC enrichment, which exploits differences in size between larger tumor cells and surrounding smaller, non-tumor blood cells, has the potential to improve CTC characterization through isolation of tumor cell populations with greater molecular heterogeneity. However, microscopic analysis of uneven filtration surfaces containing CTCs is laborious, time-consuming, and inconsistent, preventing widespread use of filtration-based enrichment technologies. Here, integrated with a microfiltration-based CTC and rare cell enrichment device we have previously described, we present a protocol for Fourier Ptychographic Microscopy (FPM), a method that, unlike many automated imaging platforms, produces high-speed, high-resolution images that can be digitally refocused, allowing users to observe objects of interest present on multiple focal planes within the same image frame. The development of a cost-effective and high-throughput CTC analysis system for filtration-based enrichment technologies could have profound clinical implications for improved CTC detection and analysis.

Liquid Biopsy in Non-Small Cell Lung Cancer

Liquid biopsy analyses are already incorporated in the routine clinical practice in many hospitals and oncology departments worldwide, improving the selection of treatments and monitoring of lung cancer patients. Although they have not yet reached its full potential, liquid biopsy-based tests will soon be as widespread as “standard” biopsies and imaging techniques, offering invaluable diagnostic, prognostic, and predictive information. This review summarizes the techniques available for the isolation and analysis of circulating free DNA and RNA, exosomes, tumor-educated platelets, and circulating tumor cells from the blood of cancer patients, presents the methodological challenges associated with each of these materials, and discusses the clinical applications of liquid biopsy testing in lung cancer.

Propofol inhibits invasion and growth of ovarian cancer cells via regulating miR-9/NF-κB signal

Propofol is one of the most commonly used intravenous anesthetic agents during cancer resection surgery. A previous study has found that propofol can inhibit invasion and induce apoptosis of ovarian cancer cells. However, the underlying mechanisms are not known. miR-9 has been reported to be little expressed in ovarian cancer cells, which has been related to a poor prognosis in patients with ovarian cancer. Studies have also demonstrated that propofol could induce microRNAs expression and suppress NF-κB activation in some situations. In the present study, we assessed whether propofol inhibits invasion and induces apoptosis of ovarian cancer cells by miR-9/NF-κB signaling. Ovarian cancer ES-2 cells were transfected with anti-miR-9 or p65 cDNA or p65 siRNA for 24 h, after which the cells were treated with different concentrations of propofol (1, 5, and 10 μg/mL) for 24 h. Cell growth and apoptosis were detected using MTT assay and flow cytometry analysis. Cell migration and invasion were detected using Transwell and Wound-healing assay. Western blot and electrophoretic mobility shift assay were used to detect different protein expression and NF-κB activity. Propofol inhibited cell growth and invasion, and induced cell apoptosis in a dose-dependent manner, which was accompanied by miR-9 activation and NF-κB inactivation. Knockdown of miR-9 abrogated propofol-induced NF-κB activation and MMP-9 expression, reversed propofol-induced cell death and invasion of ES-2 cells. Knockdown of p65 inhibited NF-κB activation rescued the miR-9-induced down-regulation of MMP-9. In addition, overexpression of p65 by p65 cDNA transfection increased propofol-induced NF-κB activation and reversed propofol-induced down-regulation of MMP-9. Propofol upregulates miR-9 expression and inhibits NF-κB activation and its downstream MMP-9 expression, leading to the inhibition of cell growth and invasion of ES-2 cells.

Propofol inhibits growth and invasion of pancreatic cancer cells through regulation of the miR-21/Slug signaling pathway

AIM

Propofol, an intravenous anesthetic agent, has been found to inhibit invasion and growth of pancreatic cancer cells in vitro. However, the mechanisms underlying these tumor-promoting phenotypes are not known. The microRNA miR-21 has been reported to be overexpressed in pancreatic cancer, and overexpression of miR-21 confers a poor prognosis to patients with pancreatic cancer. Further studies have identified the E-cadherin transcription repressor Slug as a direct target of miR-21. In this study, we assessed whether propofol inhibits invasion and growth of pancreatic cancer cells by regulation of miR-21/Slug signaling.

METHODS

PANC-1 pancreatic cancer cells were treated with different concentrations of propofol (1, 5 or 10 μg/mL) for 48 h, or 10 μg/mL propofol for 12, 24 or 36 h. Cell survival and apoptosis were detected by LDH release, BrdU cell proliferation and flow cytometry assays; cell invasion and migration were detected by transwell migration assays. miR-21 mimic (miR-21), Slug cDNA, PUMA siRNA and E-cadherin siRNA transfection was used to assess the signaling pathway in which propofol functions in PANC-1 cells. Protein and mRNA expression, respectively, were detected by western blotting and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assays.

RESULTS

Propofol inhibited growth and invasion, and induced apoptosis, in a dose- and time-dependent manner in PANC-1 cells. Propofol inhibited miR-21 levels and decreased Slug expression, resulting in an increase in Slug-dependent PUMA and E-cadherin expression in PANC-1 cells. miR-21 overexpression or PUMA or E-cadherin silencing impaired propofol-induced cell apoptosis, growth and invasion. Re-expression of Slug attenuated the expression of PUMA and E-cadherin that was induced by propofol treatment, the reduction of growth and invasion, and the increase in cell apoptosis.

CONCLUSIONS

Propofol can effectively inhibit invasion and induce apoptosis of PANC-1 cells by regulating miR-21/Slug signals.

Liquid biopsy based biomarkers in non-small cell lung cancer for diagnosis and treatment monitoring

Advances in the knowledge of the biology of non-small cell lung cancer (NSCLC) have revealed molecular information used for systemic cancer therapy targeting metastatic disease, with an important impact on patients overall survival (OS) and quality of life. However, a biopsy of overt metastases is an invasive procedure limited to certain locations and not easily acceptable in the clinic. Moreover, a single biopsy cannot reflect the clonal heterogeneity of the tumor. The analysis of peripheral blood samples of cancer patients represents a new source of cancer-derived material, known as liquid biopsy, and its components can be obtained from almost all body fluids. These components have shown to reflect characteristics of the status of both the primary and metastatic diseases, helping the clinicians to move towards a personalized medicine. The present review focuses on the liquid biopsy components: circulating tumor cells (CTCS), circulating free DNA (cfDNA), exosomes and tumor-educated platelets (TEP); the isolation technologies used and their potential use for non-invasive screening, early diagnosis, prognosis, response to treatment and real time monitoring of the disease, in NSCLC patients.

A New Cell Block Method for Multiple Immunohistochemical Analysis of Circulating Tumor Cells in Patients with Liver Cancer

PURPOSE

We developed a new method of detecting circulating tumor cells (CTCs) in liver cancer patients by constructing cell blocks from peripheral blood cells, including CTCs, followed by multiple immunohistochemical analysis.

MATERIALS AND METHODS

Cell blockswere constructed from the nucleated cell pellets of peripheral blood afterremoval of red blood cells. The blood cell blocks were obtained from 29 patients with liver cancer, and from healthy donor blood spikedwith seven cell lines. The cell blocks and corresponding tumor tissues were immunostained with antibodies to seven markers: cytokeratin (CK), epithelial cell adhesion molecule (EpCAM), epithelial membrane antigen (EMA), CK18, α-fetoprotein (AFP), Glypican 3, and HepPar1.

RESULTS

The average recovery rate of spiked SW620 cells from blood cell blocks was 91%. CTCs were detected in 14 out of 29 patients (48.3%); 11/23 hepatocellular carcinomas (HCC), 1/2 cholangiocarcinomas (CC), 1/1 combined HCC-CC, and 1/3 metastatic cancers. CTCs from 14 patients were positive for EpCAM (57.1%), EMA (42.9%), AFP (21.4%), CK18 (14.3%), Gypican3 and CK (7.1%, each), and HepPar1 (0%). Patients with HCC expressed EpCAM, EMA, CK18, and AFP in tissue and/or CTCs, whereas CK, HepPar1, and Glypican3 were expressed only in tissue. Only EMA was significantly associated with the expressions in CTC and tissue. CTC detection was associated with higher T stage and portal vein invasion in HCC patients.

CONCLUSION

This cell block method allows cytologic detection and multiple immunohistochemical analysis of CTCs. Our results show that tissue biomarkers of HCC may not be useful for the detection of CTC. EpCAM could be a candidate marker for CTCs in patients with HCC.

Circulating Tumor Cells Identify Early Recurrence in Patients with Non-Small Cell Lung Cancer Undergoing Radical Resection

Background

Surgery is the treatment of choice for patients with non-small cell lung cancer (NSCLC) stages I-IIIA. However, more than 20% of these patients develop recurrence and die due to their disease. The release of tumor cells into peripheral blood (CTCs) is one of the main causes of recurrence of cancer. The objectives of this study are to identify the prognostic value of the presence and characterization of CTCs in peripheral blood in patients undergoing radical resection for NSCLC.

Patients and Methods

56 patients who underwent radical surgery for previously untreated NSCLC were enrolled in this prospective study. Peripheral blood samples for CTC analysis were obtained before and one month after surgery. In addition CTCs were phenotypically characterized by epidermal growth factor receptor (EGFR) expression.

Results

51.8% of the patients evaluated were positive with the presence of CTCs at baseline. A decrease in the detection rate of CTCs was observed in these patients one month after surgery (32.1%) (p = 0.035). The mean number of CTCs was 3.16 per 10 ml (range 0–84) preoperatively and 0.66 (range 0–3) in postoperative determination. EGFR expression was found in 89.7% of the patients at baseline and in 38.9% patients one month after surgery. The presence of CTCs after surgery was significantly associated with early recurrence (p = 0.018) and a shorter disease free survival (DFS) (p = .008). In multivariate analysis CTC presence after surgery (HR = 5.750, 95% CI: 1.50–21.946, p = 0.010) and N status (HR = 0.296, 95% CI: 0.091–0.961, p = 0.043) were independent prognostic factors for DFS.

Conclusion

CTCs can be detected and characterized in patients undergoing radical resection for non-small cell lung cancer. Their presence might be used to identify patients with increased risk of early recurrence.

Automated Classification of Circulating Tumor Cells and the Impact of Interobsever Variability on Classifier Training and Performance

Application of personalized medicine requires integration of different data to determine each patient's unique clinical constitution. The automated analysis of medical data is a growing field where different machine learning techniques are used to minimize the time-consuming task of manual analysis. The evaluation, and often training, of automated classifiers requires manually labelled data as ground truth. In many cases such labelling is not perfect, either because of the data being ambiguous even for a trained expert or because of mistakes. Here we investigated the interobserver variability of image data comprising fluorescently stained circulating tumor cells and its effect on the performance of two automated classifiers, a random forest and a support vector machine. We found that uncertainty in annotation between observers limited the performance of the automated classifiers, especially when it was included in the test set on which classifier performance was measured. The random forest classifier turned out to be resilient to uncertainty in the training data while the support vector machine's performance is highly dependent on the amount of uncertainty in the training data. We finally introduced the consensus data set as a possible solution for evaluation of automated classifiers that minimizes the penalty of interobserver variability.

Effects of Nanotexture on Electrical Profiling of Single Tumor Cell and Detection of Cancer from Blood in Microfluidic Channels

Microfluidic channels have been implemented to detect cancer cells from blood using electrical measurement of each single cell from the sample. Every cell provided characteristic current profile based on its mechano-physical properties. Cancer cells not only showed higher translocation time and peak amplitude compared to blood cells, their pulse shape was also distinctively different. Prevalent microfluidic channels are plain but we created nanotexture on the channel walls using micro reactive ion etching (micro-RIE). The translocation behaviors of the metastatic renal cancer cells through plain and nanotextured PDMS microchannels showed clear differences. Nanotexture enhanced the cell-surface interactions and more than 50% tumor cells exhibited slower translocation through nanotextured channels compared to plain devices. On the other hand, most of the blood cells had very similar characteristics in both channels. Only 7.63% blood cells had slower translocation in nanotextured microchannels. The tumor cell detection efficiency from whole blood increased by 14% in nanotextured microchannels compared to plain channels. This interesting effect of nanotexture on translocation behavior of tumor cells is important for the early detection of cancer.

Prognostic significance of circulating tumor cells in small--cell lung cancer patients: a meta-analysis

Circulating tumor cells (CTCs) are believed to be particularly important and a reliable marker of malignancy. However, the prognostic significance of CTCs detected in patients with small cell lung cancer (SCLC) is still unclear. We therefore aimed to assess the prognostic relevance of CTCs using a meta-analysis. We searched PubMed for relevant studies and statistical analyses were conducted to calculate the hazard ratio (HR) and 95% confidence intervals (CIs) using fixed or random-effect models according to the heterogeneity of included studies. A total of 7 papers covering 440 SCLC patients were combined in the final analysis. The meta-analysis revealed that CTCs were significantly associated with shorter overall survival (HR=1.9; 95%CI: 1.19-3.04; Z=2.67; P<0.0001) and progression-free survival (HR=2.6; 95%CI: 1.9-3.54; Z=6.04; P<0.0001). The results thus suggest that the presence of CTCs indicates a poor prognosis in patients with SCLC. Further well-designed prospective studies are required to explore the clinical applications of CTCs in SCLC.

Current and potential use of MAINTRAC method for cancer diagnosis and prediction of metastasis

Cells shed from solid malignant tumors into the circulation are considered to be the origin of metastases. In spite of a wealth of research on the pathway of metastasis formation, it is still not clear when and how metastases develop, nor is there a consensus on the number and the nature of circulating tumor cells present in individual patients and their relationship to the formation of metastases. We have developed a method to detect a maximum of unselected non-hematological, epithelial cells in the blood, assuming that in cancer patients the majority of these cells are derived from the tumor. Assessment of the number of these cells longitudinally during the course of disease and therapy allows the response to different treatments to be monitored. Due to the viability of the cells, additional analyses such as expression profiles and determination of their sensitivity to drugs can be performed.

Microfluidic platform for negative enrichment of circulating tumor cells

Negative enrichment is the preferred approach for tumor cell isolation as it does not rely on biomarker expression. However, size-based negative enrichment methods suffer from well-known recovery/purity trade-off. Non-size based methods have a number of processing steps that lead to compounded cell loss due to extensive sample processing and handling which result in a low recovery efficiency. We present a method that performs negative enrichment in two steps from 2 ml of whole blood in a total assay processing time of 60 min. This negative enrichment method employs upstream immunomagnetic depletion to deplete CD45-positive WBCs followed by a microfabricated filter membrane to perform chemical-free RBC depletion and target cells isolation. Experiments of spiking two cell lines, MCF-7 and NCI-H1975, in the whole blood show an average of >90 % cell recovery over a range of spiked cell numbers. We also successfully recovered circulating tumor cells from 15 cancer patient samples.

Surgical pathway seeding of clivo-cervical chordomas

Objective Clival chordomas are slow-growing aggressive tumors that originate from the extra-axial remnants of the notochord. Current management of these tumors use surgical resection combined with radiation therapy. Given the location and invasive nature of these tumors, complete resection is difficult. A variety of both open and endoscopic therapeutic approaches have evolved and combined with the improvements in proton therapy, long-term control of these tumors appears to be improving. However, in recent literature the relatively rare complication of surgical seeding or surgical pathway recurrence has been reported. We report a case of surgical seeding following primary resection and review the world literature regarding surgical pathway recurrence.

Study Design Retrospective chart review and review of current literature.

Methods We report a case of a patient with a large chordoma that required treatment with a staged endoscopic endonasal and external transcervical approach. The patient subsequently developed recurrent disease along the cervical skin incision due to surgical seeding. Literature review and case reports were identified by a comprehensive search of Medline for the years 1950 to 2012.

Results The overall surgical pathway recurrence rate for clival chordoma resection based on analysis of the open nonendoscopic published case studies was 14 of 497 (2.8%).

Conclusion Tumor seeding can occur anywhere along the operative route and is often outside the field of radiotherapy. Increased awareness of this rare occurrence is necessary. The use of novel techniques to minimize exposure to tumor including primary endoscopic resection and so-called clean oncologic technique may help limit tumor seeding. Level of evidence: 4.

Predictive and prognostic value of circulating tumor cell detection in lung cancer: a clinician's perspective

There is increasing evidence for the use of circulating tumor cells (CTCs) as a "liquid biopsy" for early detection of lung cancer recurrence, prognosticating disease and monitoring treatment response. Further, CTC molecular analysis and interrogation of single cells hold significant potential in providing insights into tumor biology and the metastatic process. Ongoing research will likely see the translation of CTCs as a prognostic and predictive biomarker in both small cell, and non-small cell, lung cancer to routine clinical practice.

Tracking viable circulating tumor cells (CTCs) in the peripheral blood of non-small cell lung cancer (NSCLC) patients undergoing definitive radiation therapy: pilot study results

BACKGROUND

Assays identifying circulating tumor cells (CTCs) allow noninvasive and sequential monitoring of the status of primary or metastatic tumors, potentially yielding clinically useful information. However, to the authors' knowledge, the effect of radiation therapy (RT) on CTCs in patients with non-small cell lung cancer (NSCLC) has not been previously explored.

METHODS

This report describes results from a pilot study of 30 patients with NSCLC who received RT. Peripheral blood samples obtained from these patients were assayed for CTCs using an assay that identified live cells using an adenoviral probe that detected the elevated telomerase activity present in almost all cancer cells, but not in normal cells, and the validity of the assay was confirmed with secondary tumor-specific markers. Patients were assayed before initiation of RT (pre-RT), during the RT course, and/or after the completion of RT (post-RT).

RESULTS

The assay successfully detected CTCs in the majority of patients, including 65% of patients before the start of RT, and in patients with both epidermal growth factor receptor wild-type and mutation-positive tumors. The median CTC counts in patients before RT was 9.1 CTCs per mL (range, undetectable to 571 CTCs per mL) and was significantly higher than the average post-RT count of 0.6 CTCs per mL (range, undetectable to 1.8 CTCs per mL; P<.001). Sequential CTC counts were available in a subset of patients and demonstrated decreases after RT, except for 1 patient who subsequently developed distant failure.

CONCLUSIONS

The current pilot data suggest that CTC counts appear to reflect response to RT in patients with localized NSCLC. On the basis of these promising results, the authors have launched a more comprehensive and detailed clinical trial.

Fourier ptychographic microscopy for filtration-based circulating tumor cell enumeration and analysis

Circulating tumor cells (CTCs) are recognized as a candidate biomarker with strong prognostic and predictive potential in metastatic disease. Filtration-based enrichment technologies have been used for CTC characterization, and our group has previously developed a membrane microfilter device that demonstrates efficacy in model systems and clinical blood samples. However, uneven filtration surfaces make the use of standard microscopic techniques a difficult task, limiting the performance of automated imaging using commercially available technologies. Here, we report the use of Fourier ptychographic microscopy (FPM) to tackle this challenge. Employing this method, we were able to obtain high-resolution color images, including amplitude and phase, of the microfilter samples over large areas. FPM's ability to perform digital refocusing on complex images is particularly useful in this setting as, in contrast to other imaging platforms, we can focus samples on multiple focal planes within the same frame despite surface unevenness. In model systems, FPM demonstrates high image quality, efficiency, and consistency in detection of tumor cells when comparing corresponding microfilter samples to standard microscopy with high correlation (R² = 0.99932). Based on these results, we believe that FPM will have important implications for improved, high throughput, filtration-based CTC analysis, and, more generally, image analysis of uneven surfaces.

Novel tools for prostate cancer prognosis, diagnosis, and follow-up

Prostate-specific antigen (PSA) is the main diagnostic tool when it comes to prostate cancer but it possesses serious limitations. Therefore, there is an urgent need for more sensitive and specific biomarkers for prostate cancer prognosis and patient follow-up. Recent advances led to the discovery of many novel diagnostic/prognostic techniques and provided us with many worthwhile candidates. This paper briefly reviews the most promising biomarkers with respect to their implementation in screening, early detection, diagnostic confirmation, prognosis, and prediction of therapeutic response or monitoring disease and recurrence; and their use as possible therapeutic targets. This review also examines the possible future directions in the field of prostate cancer marker research.

Circulating tumor cells as a prognostic factor in patients with small cell lung cancer

The detection of circulating tumor cells (CTCs) in peripheral blood is currently an important field of study. Detection of CTCs by the OBP-401 assay (TelomeScan^®) has previously been reported to be useful in the diagnosis, prognosis and evaluation of therapeutic efficacy in breast and gastric cancer. The aim of the present study was to evaluate the OBP-401 assay as a novel method of detecting CTCs of small cell lung cancer (SCLC) patients and to evaluate whether CTC count is associated with prognosis. Prospectively, 30 consecutively diagnosed SCLC patients who had commenced chemotherapy or chemoradiotherapy were enrolled as subjects of the current study. Peripheral blood specimens were collected from the SCLC patients prior to and following the initiation of treatment and the viable CTCs were detected in the specimens following incubation with a telomerase-specific, replication-selective, oncolytic adenoviral agent, which was carrying the green fluorescent protein gene. CTCs were detected in 29 patients (96%). The group of 21 patients with a CTC count of <2 cells/7.5 ml prior to treatment (baseline) had a significantly longer median survival time than the group of eight patients with a CTC count of ≥2 cells/7.5 ml prior to treatment (14.8 and 3.9 months, respectively; P=0.007). The results of a multivariate analysis showed that the baseline CTC count was an independent prognostic factor for survival time (hazard ratio, 3.91; P=0.026). Among the patients that achieved a partial response to treatment, patients who had a CTC count of <2 cells/7.5 ml following two cycles of chemotherapy tended to have a longer median progression-free survival compared with patients who had a CTC count of ≥2 cell/7.5 ml (8.3 and 3.8 months, respectively; P=0.07). Therefore, CTCs may be detected via OBP-401 assay in SCLC patients and the CTC count prior to treatment appears to be a strong prognostic factor.

Chronic obstructive pulmonary disease in stage I non-small cell lung cancer that underwent anatomic resection: the role of a recurrence promoter

BACKGROUND

Despite the use of anatomic resection, the post-surgical recurrence rate remains high in early-stage non-small cell lung cancer (NSCLC). Chronic inflammation plays a role in the mechanism that promotes tumor initiation. This study aimed to investigate the association between recurrence outcome and chronic inflammation-related co-morbidities in early-stage resected NSCLC.

METHODS

A review of medical records for recurrence outcome and co-morbidities, in terms of chronic obstructive pulmonary disease (COPD), DM, asthma and cardiovascular diseases, was performed with 181 patients with stage I NSCLC that underwent anatomic resection.

RESULTS

Subjects with T descriptors as T2a disease (49.5 vs. 28.0%, p < 0.05) and the presence of COPD (42.4 vs. 20.7%, p < 0.01) had a higher risk of tumor recurrence. Univariate analysis for recurrence-free survival showed T descriptor as T2a (21.5 months vs. NR, p < 0.05) and the presence of COPD (20.5 months vs. NR, p < 0.01) as significant factors predicting reduced survival. The presence of COPD (HR: 1.98; 95% CI, 1.29-.02, p < 0.01) and T descriptor as T2a (HR: 2.01; 95% CI, 1.04-3.91, p < 0.05) remain independent predictors of reduced recurrence-free survival in the Cox regression model. Patients with COPD were at higher risk of brain recurrence (OR: 7.88; 95% CI, 1.50-41.3, p < 0.01). In contrast, patients without COPD showed a tendency toward recurrence in bone and liver (OR: 4.13; 95% CI, 1.08-15.8, p = 0.05).

CONCLUSION

Subjects with COPD and T2a disease had a higher risk of recurrence. The role of COPD as a recurrence promoter merits further prospective investigation.

Prognostic significance of circulating tumor cells in non-small-cell lung cancer patients: a meta-analysis

Background

The prognostic significance of circulating tumor cells (CTCs) detected in patients with non-small-cell lung cancer (NSCLC) is still inconsistent. We aimed to assess the prognostic relevance of CTCs using a meta-analysis.

Methods

We searched PubMed, Web of Science and EMBASE for relevant studies that assessed the prognostic relevance of CTCs in NSCLC. Statistical analyses were conducted to calculate the summary incidence, odds ratio, relative risks (RRs) and 95% confidence intervals (CIs) using fixed or random-effects models according to the heterogeneity of included studies.

Results

A total of 20 studies, comprising 1576 patients, met the inclusion criteria. In identified studies, CTCs were not correlated with histology (adenocarcinoma vs squamous cell carcinoma) (odds ratio [OR]  =  0.88; 95% confidence interval [CI]: 0.59–1.33; Z = –0.61; P = 0.545). However, pooled analyses showed that CTCs were associated with lymph node metastasis (OR = 2.06; 95% CI: 1.18–3.62; Z = 2.20; P = 0.027) and tumor stage (OR  = 1.95; 95% CI: 1.08–3.54; Z = 2.53; P = 0.011). Moreover, CTCs were significantly associated with shorter overall survival (relative risk [RR]  = 2.19; 95% CI: 1.53–3.12; Z = 4.32; P<0.0001) and progression-free/disease-free survival (RR  = 2.14; 95% CI: 1.36–3.38; Z = 3.28; P<0.0001).

Conclusion

The presence of CTCs indicates a poor prognosis in patients with NSCLC. Further well-designed prospective studies are required to explore the clinical applications of CTCs in lung cancer.

Circulating tumor cells: utopia or reality?

Circulating tumor cells (CTCs) could be considered a sign of tumor aggressiveness, but highly sensitive and specific methods of CTC detection are necessary owing to the rarity and heterogeneity of CTCs in peripheral blood. This review summarizes recent studies on tumor biology, with particular attention to the metastatic cascade, and the molecular characterization and clinical significance of CTCs. Recent technological approaches to enrich and detect these cells and challenges of CTCs for individualized cancer treatment are also discussed. This review also provides an insight into the positive and negative features of the future potential applications of CTC detection, which sometimes remains still a ‘utopia’, but its actual utility remains among the fastest growing research fields in oncology.

Detecting circulating tumor cells: current challenges and new trends

Circulating tumor cells (CTCs) in the blood stream play a critical role in establishing metastases. The clinical value of CTCs as a biomarker for early cancer detection, diagnosis, prognosis, prediction, stratification, and pharmacodynamics have been widely explored in recent years. However, the clinical utility of current CTC tests is limited mainly due to methodological constraints. In this review, the pros and cons of the reported CTC assays are comprehensively discussed. In addition, the potential of tumor cell-derived materials as new targets for CTC detection, including circulating tumor microemboli, cell fragments, and circulating DNA, is evaluated. Finally, emerging approaches for CTC detection, including telomerase-based or aptamer-based assays and cell functional analysis, are also assessed. Expectantly, a thorough review of the current knowledge and technology of CTC detection will assist the scientific community in the development of more efficient CTC assay systems.

Accelerated hyperfractionated radiotherapy within trimodality therapy concepts for stage IIIA/B non-small cell lung cancer: Markedly higher rate of pathologic complete remissions than with conventional fractionation

BACKGROUND

Radiation dose escalation within definitive radiochemotherapy (RTx/CTx) was not successful for stage III non-small cell lung cancer (NSCLC) using conventional fractionation (CF). Accelerated-hyperfractionation (AHF) counteracts tumour cell repopulation. In this observational study, the effects of neoadjuvant RTx/CTx using AHF or CF were studied by histopathology and using the survival end-point.

METHODS

Data from all consecutive lung cancer patients treated with neoadjuvant RTx/CTx and thoracotomy between 08/2000 and 06/2012 were analysed. Patients received induction chemotherapy (cisplatin-doublets) followed by concurrent RTx/CTx using AHF (45 Gy/1.5 Gy bid) or CF-RTx (46 Gy/2 Gy qd). For estimating the AHF versus CF treatment effects, multivariate analysis (MA), propensity score weighting (PS), and instrumental variable analysis (IV) were used.

FINDINGS

239 patients were treated, median age 58 (34-78)years, stage II/IIIA/B: 19/88/132, squamous cell/adenocarcinomas/other: 98/107/34; AHF/CF-RTx 112/127 patients. No significant differences between both groups, in tumour related factors (age, gender, Charlson comorbiditiy score, lactate dehydrogenase (LDH), haemoglobin, stage, histopathology and grading), existed. Crude rates of pathologic complete responses (pCR) in AHF and CF groups were 37% and 24% respectively. The dose fractionation effect on pCR was significant (p ⩽ 0.006, PS and IV analyses). There was a significant dependence of pCR on biologically effective dose. pCR also depended on treatment time (MA, p = 0.04; PS, p = 0.0004). Median treatment time was 22 d or 31 d using AHF or CF (p<0.0001), respectively. Adenocarcinomas had lower pCR rates in comparison to other histologies. Five-year survival of patients with pCR was 65%, independent of the fractionation.

INTERPRETATION

This large monoinstitutional analysis demonstrates an increased effect of AHF on pCR of lung cancer which modifies overall survival.