DETECTION OF DISSEMINATED TUMOR CELLS IN PERIPHERAL BLOOD

Circulating Tumor Cells are an Independent Risk Factor for Poor Prognosis in Patients with Gallbladder Adenocarcinoma

BACKGROUND

The study aimed to evaluate the prognostic impact of circulating tumor cells (CTCs) in patients with gallbladder adenocarcinoma after resection.

MATERIALS AND METHODS

Between January 2018 and January 2021, 101 consecutive patients with gallbladder adenocarcinoma were included. CTCs were detected and enumerated using the CanPatrol® technique. The follow-up period ended in January 2023. The cancer-specific survival (CSS) and disease-free survival (DFS) were calculated using log-rank and Cox regression analyses.

RESULTS

CTCs were detected positively in 61.54% (8/13) of the patients in the non-operation group and 13.64% (12/88) in the operation group. In the operation group, the median CSS for CTCs-positive and CTCs-negative patients was 5.0 and 9.5 months (P < 0.001), respectively, and DFS was 2.8 and 5.0 months at stage III (P < 0.001), respectively. In the non-operation group, the median CSS for CTCs-positive and CTCs-negative patients was 3.5 and 6.5 months (P = 0.0031), respectively. The median CSS for CTCs-positive patients in the operation group was similar to that in the non-operation group (P = 0.67). Multivariate analyses showed that positive CTCs was an independent risk factor for poor CSS (HR 0.066, 95% CI 0.021-0.206, P < 0.001) as well as lymph infiltration (HR 0.320, 95% CI 0.110-0.930, P = 0.036), without R0 curative resection (HR 7.520, 95% CI 2.100-26.931, P = 0.002), and without adjuvant chemotherapy (HR 7.730, 95% CI 2.416-24.731, P < 0.001).

CONCLUSION

Positive CTCs was an independent predictor of poor prognosis after resection in patients with gallbladder adenocarcinoma. Preoperative detection of CTCs may play an important guiding role in formulating treatment strategies for these patients.

Untethered Micro/Nanorobots for Remote Sensing: Toward Intelligent Platform

Untethered micro/nanorobots that can wirelessly control their motion and deformation state have gained enormous interest in remote sensing applications due to their unique motion characteristics in various media and diverse functionalities. Researchers are developing micro/nanorobots as innovative tools to improve sensing performance and miniaturize sensing systems, enabling in situ detection of substances that traditional sensing methods struggle to achieve. Over the past decade of development, significant research progress has been made in designing sensing strategies based on micro/nanorobots, employing various coordinated control and sensing approaches. This review summarizes the latest developments on micro/nanorobots for remote sensing applications by utilizing the self-generated signals of the robots, robot behavior, microrobotic manipulation, and robot-environment interactions. Providing recent studies and relevant applications in remote sensing, we also discuss the challenges and future perspectives facing micro/nanorobots-based intelligent sensing platforms to achieve sensing in complex environments, translating lab research achievements into widespread real applications.

Advances in liquid biopsy in neuroblastoma

Even with intensive treatment of high-risk neuroblastoma (NB) patients, half of high-risk NB patients still relapse. New therapies targeting the biological characteristics of NB have important clinical value for the personalized treatment of NB. However, the current biological markers for NB are mainly analyzed by tissue biopsy. In recent years, circulating biomarkers of NB based on liquid biopsy have attracted more and more attention. This review summarizes the analytes and methods for liquid biopsy of NB. We focus on the application of liquid biopsy in the diagnosis, prognosis assessment, and monitoring of NB. Finally, we discuss the prospects and challenges of liquid biopsy in NB.

Hydrodynamic Cavitation on a Chip: A Tool to Detect Circulating Tumor Cells

Circulating tumor cells (CTCs) are essential biomarkers for cancer diagnosis. Although various devices have been designed to detect, enumerate, and isolate CTCs from blood, some of these devices could have some drawbacks, such as the requirement of labeling, long process time, and high cost. Here, we present a microfluidic device based on the concept of "hydrodynamic cavitation-on-chip (HCOC)", which can detect CTCs in the order of minutes. The working principle relies on the difference of the required inlet pressure for cavitation inception of working fluids when they pass through the microfluidic device. The interface among the solid/floating particles, liquid, and vapor phases plays an important role in the strength of the fluid to withstand the rupture and cavitation formation. To this end, four experimental groups, including the "cell culture medium", "medium + Jurkat cells", "medium + Jurkat cells + CTCs", and "medium + CTCs", were tested as a proof of concept with two sets of fabricated microfluidic chips with the same geometrical dimensions, in which one set contained structural sidewall roughness elements. Jurkat cells were used to mimic white blood cells, and MDA-MB-231 cells were spiked into the medium as CTCs. Accordingly, the group with CTCs led to detectable earlier cavitation inception. Additionally, the effect of the CTC concentration on cavitation inception and the effect of the presence of sidewall roughness elements on the earlier inception were evaluated. Furthermore, CTC detection tests were performed with cancer cell lines spiked in blood samples from healthy donors. The results showed that this approach, HCOC, could be a potential approach to detect the presence of CTCs based on cavitation phenomenon and offer a cheap, user-friendly, and rapid tool with no requirement for any biomarker or extensive films acting as a biosensor. This approach also possesses straightforward application procedures to be employed for detection of CTCs.

Double-Tetrahedral DNA Probe Functionalized Ag Nanorod Biointerface for Effective Capture, Highly Sensitive Detection, and Nondestructive Release of Circulating Tumor Cells

Circulating tumor cells (CTCs) are indicative of tumorigenesis, metastasis, and recurrence; however, it is still a great challenge to efficiently analyze the extremely rare CTCs in peripheral blood. Herein, a novel nanobiointerface integrating high affinities of arrayed silver nanorods (Ag NRs) and double-tetrahedral DNA (DTDN) probes by a clever strategy is proposed for the efficient capture, highly sensitive detection, and nondestructive release of CTCs. Under the optimal conditions, the DTDN-probe-functionalized Ag NRs nanobiointerface can capture 90.2% of SGC-7901 cells in PBS, and the capture efficiency is 2.8 times and 50 times those of a DTDN-probe-functionalized Ag film and unfunctionalized Ag NRs, respectively, benefiting from the nanorough interface of the Ag NRs array and multivalent recognition of the DTDN probe. In addition, 93.4% of cells was released via Zn2+-assisted DNAzyme cleavage, and the viability of the postreleased CTCs is about 98.0%. The potential practicality of the nanobiointerface for testing CTCs in blood was further characterized by spiking SGC-7901 cells in leukocytes collected from human blood, and the results show that 83.8% capture efficiency, 91.2% release efficiency, and single-cell detection limit were achieved, which indicates that the nanobiointerface has great potential in clinical applications for reliable CTC analyses.

Comparison of sample preparation methods for rare cell isolation in microfluidic devices

The analysis of circulating tumor cells (CTCs) is important for cancer diagnosis and prognosis. Microfluidics has been employed for CTC analysis due to its scaling advantages and high performance. However, pre-analytical methods for CTC sample preparation are often combined with microfluidic platforms because a large sample volume is required to detect extremely rare CTCs. Among pre-analytical methods, Ficoll-Paque™, OncoQuick™, and RosetteSep™ are commonly used to separate cells of interest. To compare their performance, we spiked L3.6pl pancreatic cancer cells into healthy blood samples and then employed each technique to prepare blood samples, followed by using a microfluidic platform to capture and detect L3.6pl cells. We found these three methods have similar performance, though the slight edge of RosetteSep™ over Ficoll-Paque™ is statistically significant. We also studied the effects of the tumor cell concentrations on the performance of the frequently used Ficoll-Paque™ method. Furthermore, we examined the repeatability and variability of each pre-analytical technique and the microfluidics-enabled detection. This study will provide researchers and clinicians with comparative data that can influence the choice of sample preparation method, help estimate CTC loss in each pre-analytical method, and correlate the results of clinical studies that employ different techniques.

Unraveling Cancer Metastatic Cascade Using Microfluidics-based Technologies

Cancer has long been a leading cause of death. The primary tumor, however, is not the main cause of death in more than 90% of cases. It is the complex process of metastasis that makes cancer deadly. The invasion metastasis cascade is the multi-step biological process of cancer cell dissemination to distant organ sites and adaptation to the new microenvironment site. Unraveling the metastasis process can provide great insight into cancer death prevention or even treatment. Microfluidics is a promising platform, that provides a wide range of applications in metastasis-related investigations. Cell culture microfluidic technologies for in vitro modeling of cancer tissues with fluid flow and the presence of mechanical factors have led to the organ-on-a-chip platforms. Moreover, microfluidic systems have also been exploited for capturing and characterization of circulating tumor cells (CTCs) that provide crucial information on the metastatic behavior of a tumor. We present a comprehensive review of the recent developments in the application of microfluidics-based systems for analysis and understanding of the metastasis cascade from a wider perspective.

Circulating tumor cells as a "real-time liquid biopsy": Recent advances and the application in ovarian cancer

Even with the latest advances in technology, the treatment of ovarian cancer remains a big challenge because it is typically diagnosed at advanced stage, is prone to early relapse in spite of aggressive treatment and has an extremely poor prognosis. Circulating tumor cells (CTCs) can be used as a non-invasive "real-time liquid biopsy", which has shown the value of diagnosis, assessment of prognosis and chemoresistance, and detection of small residual tumors on ovarian cancer. This review article provides an overview on recent research on CTCs in ovarian cancer, with special focus on the clinical application of CTC tests.

An Automatic Platform Based on Nanostructured Microfluidic Chip for Isolating and Identification of Circulating Tumor Cells

Circulating tumor cell (CTC) test is currently used as a biomarker in cancer treatment. Unfortunately, the poor reproducibility and limited sensitivity with the CTC detection have limited its potential impact on clinical application. A reliable automated CTC detection system is therefore needed. We have designed an automated microfluidic chip-based CTC detection system and hypothesize this novel system can reliably detect CTC from clinical specimens. SKOV3 ovarian cancer cell line was used first to test the reliability of our system. Ten healthy volunteers, 5 patients with benign ovarian tumors, and 8 patients with epithelial ovarian cancer (EOC) were recruited to validate the CTC capturing efficacy in the peripheral blood. The capture rates for spiking test in SKOV3 cells were 48.3% and 89.6% by using anti-EpCAM antibody alone and a combination of anti-EpCAM antibody and anti-N-cadherin antibody, respectively. The system was sensitive to detection of low cell count and showed a linear relationship with the cell counts in our test range. The sensitivity and specificity were 62.5% and 100% when CTC was used as a biomarker for EOC. Our results demonstrated that this automatic CTC platform has a high capture rate and is feasible for detection of CTCs in EOC.

Multifunctional microfluidic chip for cancer diagnosis and treatment

Microfluidic chip is not a chip in the traditional sense. It is technologies that control fluids at the micro level. As a burgeoning biochip, microfluidic chips integrate multiple disciplines, including physiology, pathology, cell biology, biophysics, engineering mechanics, mechanical design, materials science, and so on. The application of microfluidic chip has shown tremendous promise in the field of cancer therapy in the past three decades. Various types of cell and tissue cultures, including 2D cell culture, 3D cell culture and tissue organoid culture could be performed on microfluidic chips. Patient-derived cancer cells and tissues can be cultured on microfluidic chips in a visible, controllable, and high-throughput manner, which greatly advances the process of personalized medicine. Moreover, the functionality of microfluidic chip is greatly expanding due to the customizable nature. In this review, we introduce its application in developing cancer preclinical models, detecting cancer biomarkers, screening anti-cancer drugs, exploring tumor heterogeneity and producing nano-drugs. We highlight the functions and recent development of microfluidic chip to provide references for advancing cancer diagnosis and treatment.

Simultaneous on-chip isolation and characterization of circulating tumor cell sub-populations

The diagnosis of tumor metastasis using circulating tumor cells (CTCs) has been considered an important developmental target for several decades but remains a formidable challenge because of the rarity and heterogeneity of CTCs. Additional downstream analysis is required after isolating CTCs on-chip for subtype verification. To solve those problems, we have developed microfluidic based integrated system which uses magnetic field gradient and immune-fluorescence differences to on-chip isolation and discrimination of CTCs simultaneously. The system presented in the present study can isolate CTCs with an efficiency of >99% by utilizing magnetic nanoparticles conjugated to CTC membranes. Furthermore, the statuses of three biomarkers can be determined on-chip simultaneously. The devised microfluidic system can differentiate eight different subtypes of heterogenic CTCs by on-chip isolation and based on the statuses of three biomarkers (HER2, ER, and PR) which are critical variables to five-year overall survivals for breast cancer patients.

Circulating Tumor Cell Migration Requires Fibronectin Acting through Integrin B1 or SLUG

Fibronectin (FN1) is an extracellular matrix protein gaining increasing attention for its multifaceted roles in cancer progression. Using our recently established circulating tumor cell (CTC) lines, we had demonstrated increased FN1 expression and enhanced migration in CTC lines, in comparison to primary tumor cell lines. Whether increased FN1 expression is directly required for CTC migration, and the specific role of FN1’s regulation of integrin B1 (ITGB1) and SLUG (SNAI2) in CTC migration remains unclear. Here, for the first time, we report that the knockdown of FN1, ITGB1, or SLUG expression in CTCs leads to a significant decrease in CTC migration. Knocking down two or all three of these proteins simultaneously did not further inhibit migration. We observed a corresponding increase in CTC migration when recombinant FN1 was added to CTCs. This effect was significantly impeded by prior knockdown of ITGB1 or SLUG. Using knock down experiments and western blotting analysis, we confirmed FN1’s regulation of ITGB1 and SLUG to occur via two separate, independent pathways. Consequently, we can conclude that FN1-dependent enhanced migration of CTCs requires downstream signaling through either ITGB1 or SLUG and that FN1 regulation of ITGB1 and SLUG may have important implications for cancer progression and metastasis.

Enrichment of Circulating Tumor Cells from Whole Blood Using a Microfluidic Device for Sequential Physical and Magnetophoretic Separations

Based on their high clinical potential, the isolation and enrichment of rare circulating tumor cells (CTCs) from peripheral blood cells has been widely investigated. There have been technical challenges with CTC separation methods using solely cancer-specific surface molecules or just using physical properties of CTCs, as they may suffer from heterogeneity or lack of specificity from overlapping physical characteristics with leukocytes. Here, we integrated an immunomagnetic-based negative enrichment method that utilizes magnetic beads attached to leukocyte-specific surface antigens, with a physical separation method that utilizes the distinct size and deformability of CTCs. By manipulating the pressure distribution throughout the device and balancing the drag and magnetic forces acting on the magnetically labeled white blood cells (WBCs), the sequential physical and magnetophoretic separations were optimized to isolate intact cancer cells, regardless of heterogeneity from whole blood. Using a breast cancer cell line in whole blood, we achieved 100% separation efficiency for cancer cells and an average of 97.2% for WBCs, which resulted in a 93.3% average separation purity. The experimental results demonstrated that our microfluidic device can be a promising candidate for liquid biopsy and can be a vital tool for aiding future cancer research.

Rapid Detection of Circulating Breast Cancer Cells Using a Multiresonant Optical Fiber Aptasensor with Plasmonic Amplification

The detection of circulating tumor cells (CTCs), which are responsible for metastasis in several forms of cancer, represents an important goal in oncological diagnosis and treatment. These cells remain extremely challenging to detect, despite numerous previous studies, due to their low concentration (1-10 cells/mL of blood). In this work, an all-fiber plasmonic aptasensor featuring multiple narrowband resonances in the near-infrared wavelength range was developed to detect metastatic breast cancer cells. To this aim, specific aptamers against mammaglobin-A were selected and immobilized as receptors on the sensor surface. In vitro assays confirm that the label-free and real-time detection of cancer cells [limit of detection (LOD) of 49 cells/mL] occurs within 5 min, while the additional use of functionalized gold nanoparticles allows a 2-fold amplification of the biosensor response. Differential measurements on selected optical resonances were used to process the sensor response, and results were confirmed by microscopy. The detection of only 10 cancer cells/mL was achieved with relevant specificity against control cells and with quick response time.

Single Cell Transcriptome in Colorectal Cancer-Current Updates on Its Application in Metastasis, Chemoresistance and the Roles of Circulating Tumor Cells

Colorectal cancer (CRC) is among the most common cancer worldwide, a challenge for research, and a model for studying the molecular mechanisms involved in its development. Previously, bulk transcriptomics analyses were utilized to classify CRC based on its distinct molecular and clinicopathological features for prognosis and diagnosis of patients. The introduction of single-cell transcriptomics completely turned the table by enabling the examination of the expression levels of individual cancer cell within a single tumor. In this review, we highlighted the importance of these single-cell transcriptomics analyses as well as suggesting circulating tumor cells (CTCs) as the main focus of single-cell RNA sequencing. Characterization of these cells might reveal the intratumoral heterogeneity present in CRC while providing critical insights into cancer metastasis. To summarize, we believed the analysis of gene expression patterns of CTC from CRC at single-cell resolution holds the potential to provide key information for identification of prognostic and diagnostic markers as well as the development of precise and personalized cancer treatment.

Mitotic quiescence in hepatic cancer stem cells: An incognito mode

Hepatocellular carcinoma represents one of the most aggressive cancers with high recurrence rates. The high recurrence is a major problem in the management of this disease. Cancer stem cells (CSCs) are often regarded as the basis of cancer recurrence. The anti-proliferative therapy kills the proliferating cells but induces mitotic quiescence in CSCs which remain as residual dormant CSCs. Later on, withdrawal of treatment reactivates the residual CSCs from dormancy to produce new cancer cells. The proliferation of these newly formed cancer cells initiates new tumor formation in the liver leading to tumor recurrence. HCC cells evade the immune surveillance via modulating the key immune cells by alpha feto-protein (AFP) secreted from CSCs or hepatic progenitor cells. This AFP mediated immune evasion assists in establishing new tumors by cancer cells in the liver. In this review, we will summarise the CSC mechanisms of recurrence, mitotic quiescence, dormancy and reactivation of CSCs, metastasis and immune evasion of hepatocellular carcinoma.

Nanotechnology in Radiation Oncology

Nanotechnology has made remarkable contributions to clinical oncology. Nanotherapeutics and diagnostic tools have distinctive characteristics which allow them superior abilities to deliver therapeutics and imaging agents for radiation oncology. Compared to solid biopsies and imaging, the analysis of circulating tumor cells (CTCs) offers a more rapid, real-time, and less invasive method to monitor the dynamic molecular profiles of tumors. The potential of CTCs to be translated as a novel cancer biomarker has been demonstrated in numerous clinical studies. This review will discuss clinical applications of nanomaterials in radiation oncology and the implication of CTCs in cancer detection and monitoring.

Separation detection of different circulating tumor cells in the blood using an electrochemical microfluidic channel modified with a lipid-bonded conducting polymer

Different circulating tumor cells (CTCs) in blood were separated and detected through the decoration of anti-cancer drug on the target cells, along with chemical modification of the microfluidic channel walls using a lipid attached covalently to the conducting polymer. The working principle of the electrochemical microfluidic device was evaluated with experimental parameters affecting on the separation, in terms of mass and surface charge of target species, fluid flow rate, AC amplitude, and AC frequency. The separated CTCs were selectively detected via the oxidation of daunomycin adsorbed specifically at the cells using an electrochemical sensor installed at the channel end. The fluorescence microscopic examination also confirmed the separation of CTCs in the channel. To evaluate the reliability of the method, blood samples from 37 cancer patients were tested. The device was able to separate the CTCs with 92.0 ± 0.5 % efficiency and 90.9% detection rate.

Enumeration And Characterization Of Circulating Tumor Cells And Its Application In Advanced Gastric Cancer

Background

Advanced gastric cancer (aGC) has a high global incidence and a high mortality rate and because of its high malignancy and heterogeneity, the existing methods for prognosis are limited, and a new treatment model is necessary. Circulating tumor cells (CTCs) could be considered as a “liquid biopsy” for tumor diagnosis and for monitoring treatment responses and predicting clinical outcome. Clinical studies support the efficacy of programmed cell death 1 (PD-1) immunotherapy in a subset of aGC.

Methods

Cell capture efficiency, as described by the CanPatrol CTC enrichment technique, was validated using artificial blood samples as well as blood samples from 32 aGC patients. Clinicopathologic data of patients were collected from the hospital information system. We used CanPatrol for CTC isolation, classification, and clinical analysis.

Results

A cell capture efficiency of >80% was achieved. Significant correlation was observed between CTC enumeration and clinicopathology parameters, including the Lauren classification (r=0.470, P=0.008), perineural invasion (r=0.393, P=0.029), TNM stage (r=0.740, P<0.001), and Ki-67 level (r=0.510, P=0.005). When compared to the traditional methods, monitoring CTC subtypes exhibits higher sensitivity of evaluating the disease status. Enumeration of epithelial CTC subset and its relative abundance in the total CTC pool are highly correlated with clinical efficacy. CTC programmed cell death ligand-1 (PD-L1) could be successfully detected for immunotherapy in addition to PD-L1 immunohistochemistry and microsatellite instability.

Conclusion

We provide a new method that allows for the simple and effective detection of CTCs in aGC. It has potential clinical applications in monitoring prognosis and guiding future individualized immunotherapy.

TiO2 nanopillar arrays coated with gelatin film for efficient capture and undamaged release of circulating tumor cells

Circulating tumor cells (CTCs) are important for the detection and treatment of cancer. Nevertheless, a low density of circulating tumor cells makes the capture and release of CTCs an obstacle. In this work, TiO₂ nanopillar arrays coated with gelatin film were synthesized for efficient capture and undamaged release of circulating tumor cells. The scanning electron microscope and atomic force microscope images demonstrate that the substrate has a certain roughness. The interaction between the cell membrane and the nanostructure substrate contributes to the efficient capture of CTC (capture efficiency up to 94.98%). The gelatin layer has excellent biocompatibility and can be rapidly digested by matrix metalloproteinase (MMP9), which realizes the non-destructive release of CTCs (0.1 mg ml^-1, 5 min, nearly 100% release efficiency, activity 100%). Therefore, by our strategy, the CTCs can be efficiently captured and released undamaged, which is important for subsequent analysis.

Fibronectin Regulation of Integrin B1 and SLUG in Circulating Tumor Cells

Metastasis is the leading cause of cancer death worldwide. Circulating tumor cells (CTCs) are a critical step in the metastatic cascade and a good tool to study this process. We isolated CTCs from a syngeneic mouse model of hepatocellular carcinoma (HCC) and a human xenograft mouse model of castration-resistant prostate cancer (CRPC). From these models, novel primary tumor and CTC cell lines were established. CTCs exhibited greater migration than primary tumor-derived cells, as well as epithelial-to-mesenchymal transition (EMT), as observed from decreased E-cadherin and increased SLUG and fibronectin expression. Additionally, when fibronectin was knocked down in CTCs, integrin B1 and SLUG were decreased, indicating regulation of these molecules by fibronectin. Investigation of cell surface molecules and secreted cytokines conferring immunomodulatory advantage to CTCs revealed decreased major histocompatibility complex class I (MHCI) expression and decreased endostatin, C-X-C motif chemokine 5 (CXCL5), and proliferin secretion by CTCs. Taken together, these findings indicate that CTCs exhibit distinct characteristics from primary tumor-derived cells. Furthermore, CTCs demonstrate enhanced migration in part through fibronectin regulation of integrin B1 and SLUG. Further study of CTC biology will likely uncover additional important mechanisms of cancer metastasis.

Combined Features Based on Preoperative Controlling Nutritional Status Score and Circulating Tumour Cell Status Predict Prognosis for Colorectal Cancer Patients Treated with Curative Resection

Background: The preoperative controlling nutritional status (CONUT) score and circulating tumour cell (CTC) status are associated with poor prognosis of colorectal cancer (CRC). The aim of the present study is to determine whether the combination of CONUT and CTC (CONUT-CTC) could better predict the prognosis of CRC patients treated with curative resection.

Methods: Preoperative CONUT score was retrospectively calculated in 160 CRC patients who underwent curative resection at Zhongnan Hospital of Wuhan University from 2015 to 2017. Preoperative CTC counts were enumerated from 5 ml peripheral vein blood by a CTCBIOPSY® device. According to the preoperative CONUT and CTC status, the patients were divided into three groups: CONUT-CTC (0), CONUT-CTC (1) and CONUT-CTC (2). The relationship between CONUT score and CTC, as well as the associations of CONUT-CTC status with clinicopathological factors and survival, were evaluated.

Results: Preoperatively, the number and positive rate of CTC were positively correlated with the preoperative CONUT score (P<0.01). An elevated CONUT-CTC score was significantly associated with deeper tumour invasion (P=0.025), lymphatic vessel invasion (P=0.002), venous invasion (P<0.001) and higher pTNM stage (P=0.033). Kaplan-Meier analysis and log-rank tests revealed significant decreases in recurrence-free survival (RFS) and cancer-specific survival (CSS) among CRC patients with CONUT-CTC score of 0, 1 and 2 (P<0.001). In pTNM stage-stratified analysis, high CONUT-CTC score was significantly associated with the poor (P<0.001) and CSS (P<0.001) of patients with stage III disease, but not correlated with the prognosis of patients with stage II disease (RFS: P=0.077; CSS: P<0.090). Further univariate and multivariate analyses showed that CONUT-CTC was an independent factor affecting patients' RFS [hazard ratio (HR)=2.66, 95% confidence interval (CI):1.79-3.96, P<0.001] and CSS (HR=3.75, 95%CI: 2.14-6.57, P<0.001). In time-dependent receiver operating characteristics (ROC) analyses, CONUT-CTC score had a higher area under the ROC curve (AUC) for the prediction of RFS and CSS than did preoperative CONUT score or CTC status.

Conclusion: The preoperative CONUT-CTC score is associated with tumour progression and poor prognosis in patients with CRC treated with curative resection, indicating that better information on CRC prognosis could be obtained from combined preoperative host immune-nutritional status and CTC detection.

Membrane Hsp70-A Novel Target for the Isolation of Circulating Tumor Cells After Epithelial-to-Mesenchymal Transition

The presence of circulating tumor cells (CTCs) in the peripheral blood is a pre-requisite for progression, invasion, and metastatic spread of cancer. Consequently, the enumeration and molecular characterization of CTCs from the peripheral blood of patients with solid tumors before, during and after treatment serves as a valuable tool for categorizing disease, evaluating prognosis and for predicting and monitoring therapeutic responsiveness. Many of the techniques for isolating CTCs are based on the expression of epithelial cell surface adhesion molecule (EpCAM, CD326) on tumor cells. However, the transition of adherent epithelial cells to migratory mesenchymal cells (epithelial-to-mesenchymal transition, EMT)-an essential element of the metastatic process-is frequently associated with a loss of expression of epithelial cell markers, including EpCAM. A highly relevant proportion of mesenchymal CTCs cannot therefore be isolated using techniques that are based on the "capture" of cells expressing EpCAM. Herein, we provide evidence that a monoclonal antibody (mAb) directed against a membrane-bound form of Hsp70 (mHsp70)-cmHsp70.1-can be used for the isolation of viable CTCs from peripheral blood of tumor patients of different entities in a more quantitative manner. In contrast to EpCAM, the expression of mHsp70 remains stably upregulated on migratory, mesenchymal CTCs, metastases and cells that have been triggered to undergo EMT. Therefore, we propose that approaches for isolating CTCs based on the capture of cells that express mHsp70 using the cmHsp70.1 mAb are superior to those based on EpCAM expression.

Wedge-shaped microfluidic chip for circulating tumor cells isolation and its clinical significance in gastric cancer

Background

Circulating tumor cells (CTCs) have great potential in both basic research and clinical application for the managements of cancer. However, the complicated fabrication processes and expensive materials of the existing CTCs isolation devices, to a large extent, limit their clinical translation and CTCs’ clinical value. Therefore, it remains to be urgently needed to develop a new platform for achieving CTCs detection with low-cost, mass-producible but high performance.

Methods

In the present study, we introduced a novel wedge-shaped microfluidic chip (named CTC-ΔChip) fabricated by two pieces of glass through wet etching and thermal bonding technique for CTCs isolation, which achieved CTCs enrichment by different size without cell surface expression markers and CTCs identification with three-color immunocytochemistry method (CK+/CD45−/Nucleus+). We validated the feasibility of CTC-ΔChip for detecting CTCs from different types of solid tumor. Furthermore, we applied the newly-developed platform to investigate the clinical significance of CTCs in gastric cancer (GC).

Results

Based on “label-free” characteristic, the capture efficiency of CTC-ΔChip can be as high as 93.7 ± 3.2% in DMEM and 91.0 ± 3.0% in whole blood sample under optimized conditions. Clinically, CTC-ΔChip exhibited the feasibility of detecting CTCs from different types of solid tumor, and it identified 7.30 ± 7.29 CTCs from 2 mL peripheral blood with a positive rate of 75% (30/40) in GC patients. Interestingly, we found that GC CTCs count was significantly correlated with multiple systemic inflammation indexes, including the lymphocyte count, platelet count, the level of neutrophil to lymphocyte ratio and platelet to lymphocyte ratio. In addition, we also found that both the positivity rate and CTCs count were significantly associated with multiple clinicopathology parameters.

Conclusions

Our novel CTC-ΔChip shows high performance for detecting CTCs from less volume of blood samples of cancer patients and important clinical significance in GC. Owing to the advantages of low-cost and mass-producible, CTC-ΔChip holds great potential of clinical application for cancer therapeutic guidance and prognostic monitoring in the future.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1521-8) contains supplementary material, which is available to authorized users.

Emerging biomarkers in the diagnosis of prostate cancer

Prostate cancer (PCa) is the second most common cancer in men worldwide. A large proportion of PCa are latent, never destined to progress or affect the patients’ life. It is of utmost importance to identify which PCa are destined to progress and which would benefit from an early radical treatment. Prostate-specific antigen (PSA) remains the most used test to detect PCa. Its limited specificity and an elevated rate of overdiagnosis are the main problems associated with PSA testing. New PCa biomarkers have been proposed to improve the accuracy of PSA in the management of early PCa. Commercially available biomarkers such as PCA3 score, Prostate Health Index (PHI), and the four-kallikrein panel are used with the purpose of reducing the number of unnecessary biopsies and providing information related to the aggressiveness of the tumor. The relationship with PCa aggressiveness seems to be confirmed by PHI and the four-kallikrein panel, but not by the PCA3 score. In this review, we also summarize new promising biomarkers, such as PSA glycoforms, TMPRSS2:ERG fusion gene, microRNAs, circulating tumor cells, androgen receptor variants, and PTEN gene. All these emerging biomarkers could change the management of early PCa, offering more accurate results than PSA. Nonetheless, large prospective studies comparing these new biomarkers among them are required to know their real value in PCa detection and prognosis.

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.

Rapid and highly efficient capture and release of cancer cells using polymeric microfibers immobilized with enzyme-cleavable peptides

Circulating tumor cells (CTCs) are tumor cells present in the blood. CTCs have attracted much attention as a new tumor marker, because their analysis provides useful information for monitoring cancer progress. In this study, we developed cell-capture and release methods using three-dimensional (3D) microfiber fabrics without damaging the cells. Using functional peptides containing sequences from a polystyrene-binding site and a cleavable site for collagenase type IV, immobilized antibodies on the peptides were able to specifically capture MCF-7 cells in a few minutes and release the captured cells from 3D microfiber fabrics incorporating a vacuum system. The efficiency of cell capture was around 80% and that of the cell release was over 90%. The released cells proliferated normally in culture medium, suggesting that our system will be applicable for the culture and analysis of CTCs.

STATEMENT OF SIGNIFICANCE

In this paper, we report cell-capture and release methods using enzyme-cleavable peptides immobilized on microfiber fabrics which has microporous polymeric three-dimensional structures. Detachment and collection of the selectively captured cancer cells are required for ex vivo culture and their further analysis, whereas the cell detachment methods developed so far might cause cell damage, even if cell viability is high enough. Therefore, specific attachment and gentle detachment from the device are required for the accurate analysis of cells. In this study, for capture and release of cancer cells we designed the peptide cleavable by collagenase type IV, which has no target molecule in cells. Our system will be useful for further CTC analysis and might lead to more accurate cancer diagnosis.

CK19, CK20, EGFR and HER2 Status of Circulating Tumor Cells in Patients with Breast Cancer

Aims and background

The major cause of death in breast cancer patients is metastasis. Various biomarkers have been used for the early detection of circulating tumor cells in the peripheral blood of breast cancer patients. The aims of the current study were to analyze circulating tumor cells in the blood of breast cancer patients by investigating EGFR, CK19, CK20 and HER2 expression profiles and to evaluate their prognostic importance.

Methods

CK19, CK20 and EGFR gene expression profiles were evaluated in the blood samples of 84 female patients with primary invasive ductal breast cancer and 20 healthy female volunteers using SYBR green-based real-time qPCR assays. HER2 expression analyses were conducted in 46 patients who had an HER2-positive primary tumor and in 30 healthy women to determine the cutoff level of positivity.

Results

The positive rates of CK20, EGFR, CK19 and HER2 mRNA expression in the peripheral blood were 28.57% (24/84), 20.23% (17/84), 5.95% (5/84) and 2.17% (1/46), respectively. The high positive ratio of CK20 mRNA expression in the peripheral blood of breast cancer was identified for the first time in the current study. Significant differences were identified in CK20 expression status and several clinical parameters related with aggressiveness of tumors using a binary logistic regression analysis. Higher CK20-positive levels were observed in patients who had lymph node metastasis and advanced-grade primary tumors, which were estrogen receptor-negative. We have demonstrated that CK20 may be a novel biomarker that is useful to identify circulating tumor cells and predict breast cancer progression.

Conclusions

The results suggest that the investigation of CK20 mRNA with other biomarkers in the peripheral blood of breast cancer patients may be useful to monitor the presence of disseminated tumor cells in the blood circulation and to predict the prognosis of breast cancer.

High-dimension single-cell analysis applied to cancer

High-dimension single-cell technology is transforming our ability to study and understand cancer. Numerous studies and reviews have reported advances in technology development. The biological insights gleaned from single-cell technology about cancer biology are less reviewed. Here we focus on research studies that illustrate novel aspects of cancer biology that bulk analysis could not achieve, and discuss the fresh insights gained from the application of single-cell technology across basic and clinical cancer studies.

EMT: Mechanisms and therapeutic implications

Metastasis, the dissemination of cancer cells from primary tumors, represents a major hurdle in the treatment of cancer. The epithelial-mesenchymal transition (EMT) has been studied in normal mammalian development for decades, and it has been proposed as a critical mechanism during cancer progression and metastasis. EMT is tightly regulated by several internal and external cues that orchestrate the shifting from an epithelial-like phenotype into a mesenchymal phenotype, relying on a delicate balance between these two stages to promote metastatic development. EMT is thought to be induced in a subset of metastatic cancer stem cells (MCSCs), bestowing this population with the ability to spread throughout the body and contributing to therapy resistance. The EMT pathway is of increasing interest as a novel therapeutic avenue in the treatment of cancer, and could be targeted to prevent tumor cell dissemination in early stage patients or to eradicate existing metastatic cells in advanced stages. In this review, we describe the sequence of events and defining mechanisms that take place during EMT, and how these interactions drive cancer cell progression into metastasis. We summarize clinical interventions focused on targeting various aspects of EMT and their contribution to preventing cancer dissemination.

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.

Comparison of three different methods for the detection of circulating tumor cells in mice with lung metastasis

Circulating tumor cells (CTCs) represent the key step of cancer cell dissemination. The alteration of CTCs correlates with the treatment outcome and prognosis. To enrich and identify CTCs from billions of blood cells renders a very challenging task, which triggers development of several methods, including lysis of RBC plus negative or positive enrichment using antibodies, and filter membrane or spiral microfluidics to capture CTCs. To compare the advantages of different enrichment methods for CTCs, we utilized the 4T1 breast cancer cells transfected with both green fluorescent protein (GFP) and luciferase to trace CTCs in the experimental lung metastasis model. Three methods were used to detect CTCs at the same time: bioluminescence assay, smearing method, and membrane filter method. The in vivo alive mouse imaging was used to dynamically monitor the growth of lung metastases. The sensitivity and accuracy of three detection methods were compared side-by-side. Our results showed that 1) the sensitivity of bioluminescence assay was the highest, but there was no information of CTC morphology; 2) the smearing method and membrane filter method could observe the detail of CTC morphology, such as in single or in cluster, while their sensitivity was lower than bioluminescence assay; 3) A dynamic observation at a 7-day intervals, the lung metastatic cancer grew at a log speed, while CTCs were increased at a low speed. This might be due to the activated immune cells eliminating the CTCs at a speed much faster than CTCs were generated. This comparison of three CTC detection methods in mouse model suggests that bioluminescence assay could be used in quantitative study of the effect of certain agent on the suppression of CTCs, while GFP-based morphological assays could be used to study the dissemination mechanism of CTCs. The combination of both bioluminescence assay and GFP-based assay would generate more information for quantity and quality of CTCs.

Aptamer-functionalized nano/micro-materials for clinical diagnosis: isolation, release and bioanalysis of circulating tumor cells

Detection of rare circulating tumor cells (CTCs) in peripheral blood is a challenging, but necessary, task in order to diagnose early onset of metastatic cancer and to monitor treatment efficacy. Over the last decade, step-up produced aptamers have attracted great attention in clinical diagnosis. They have offered great promise for a broader range of cell-specific recognition and isolation. In particular, aptamer-functionalized magnetic particles for selective extraction of target CTCs have shown reduced damage to cells and relatively simple operation. Also, efforts to develop aptamer-functionalized microchannel/microstructures able to efficiently isolate target CTCs are continuing, and these efforts have brought more advanced geometrically designed substrates. Various aptamer-mediated cell release techniques are being developed to enable subsequent biological studies. This article reviews some of these advances in aptamer-functionalized nano/micro-materials for CTCs isolation and methods for releasing captured CTCs from aptamer-functionalized surfaces. Biological studies of CTCs after release are also discussed.

Improving sensitivity and specificity of capturing and detecting targeted cancer cells with anti-biofouling polymer coated magnetic iron oxide nanoparticles

Detecting circulating tumor cells (CTCs) with high sensitivity and specificity is critical to management of metastatic cancers. Although immuno-magnetic technology for in vitro detection of CTCs has shown promising potential for clinical applications, the biofouling effect, i.e., non-specific adhesion of biomolecules and non-cancerous cells in complex biological samples to the surface of a device/probe, can reduce the sensitivity and specificity of cell detection. Reported herein is the application of anti-biofouling polyethylene glycol-block-allyl glycidyl ether copolymer (PEG-b-AGE) coated iron oxide nanoparticles (IONPs) to improve the separation of targeted tumor cells from aqueous phase in an external magnetic field. PEG-b-AGE coated IONPs conjugated with transferrin (Tf) exhibited significant anti-biofouling properties against non-specific protein adsorption and off-target cell uptake, thus substantially enhancing the ability to target and separate transferrin receptor (TfR) over-expressed D556 medulloblastoma cells. Tf conjugated PEG-b-AGE coated IONPs exhibited a high capture rate of targeted tumor cells (D556 medulloblastoma cell) in cell media (58.7±6.4%) when separating 100 targeted tumor cells from 1×105 non-targeted cells and 41 targeted tumor cells from 100 D556 medulloblastoma cells spiked into 1mL blood. It is demonstrated that developed nanoparticle has higher efficiency in capturing targeted cells than widely used micron-sized particles (i.e., Dynabeads®).

Detection of circulating tumor cells with CK20 RT-PCR is an independent negative prognostic marker in colon cancer patients - a prospective study

Background

Detection of circulating (CTC) or disseminated tumor cells (DTC) has been associated with negative prognosis and outcome in patients with colorectal cancer, though testing for these cells is not yet part of clinical routine. There are several different methodological approaches to detect tumor cells but standardized detection assays are not implemented so far.

Methods

In this prospective monocentric study 299 patients with colon cancer were included. CTC and DTC were detected using CK20 RT-PCR as well as immunocytochemistry staining with anti-pan-keratin and anti-EpCAM antibodies. The primary endpoints were: Evaluation of CTC and DTC at the time of surgery and correlation with main tumor characteristics and overall (OS) and disease free survival (DFS).

Results

Patients with detectable CTC had a 5-year OS rate of 68% compared to a 5-year OS rate of 85% in patients without detectable CTC in the blood (p = 0.002). Detection of DTC in the bone marrow with CK20 RT-PCR was not associated with a worse OS or DFS. Detection of pan-cytokeratin positive DTC in the bone marrow correlated with a significantly reduced 5-year OS rate (p = 0.048), but detection of DTC in the bone marrow with the anti-EpCAM antibody did not significantly influence the 5-year OS rate (p = 0.958). By multivariate analyses only detection of CTC with CK20 RT-PCR in the blood was revealed to be an independent predictor of worse OS (HR1.94; 95% CI 1.0–3.7; p = 0.04) and DFS (HR 1.94; 95% CI 1.1–3.7; p = 0.044).

Conclusions

Detection of CTC with CK20 RT-PCR is a highly specific and independent prognostic marker in colon cancer patients. Detection of DTC in the bone marrow with CK20 RT-PCR or immunohistochemistry with anti-EpCAM antibody is not associated with a negative prognostic influence.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-3035-1) contains supplementary material, which is available to authorized users.

Fast and selective cell isolation from blood sample by microfiber fabric system with vacuum aspiration

Since circulating tumor cells (CTCs) are tumor cells which are found in the blood of cancer patients, CTCs are potential tumor markers, so a rapid isolation of CTCs is desirable for clinical applications. In this paper, a three-dimensional polystyrene (PS) microfiber fabric with vacuum aspiration system was developed for capturing CTCs within a short time. Various microfiber fabrics with different diameters were prepared by the electrospinning method and optimized for contact frequency with cells. Vacuum aspiration utilizing these microfiber fabrics could filter all cells within seconds without mechanical damage. The microfiber fabric with immobilized anti-EpCAM antibodies was able to specifically capture MCF-7 cells that express EpCAM on their surfaces. The specificity of the system was confirmed by monitoring the ability to isolate MCF-7 cells from a mixture containing CCRF-CEM cells that do not express EpCAM. Furthermore, the selective capture ability of the microfiber was retained even when the microfiber was exposed to the whole blood of pigs spiked with MCF-7 cells. The specific cell capture ratio of the vacuum aspiration system utilizing microfiber fabric could be improved by increasing the thickness of the microfiber fabric through electrospinning time.

Highly sensitive dual mode electrochemical platform for microRNA detection

MicroRNAs (miRNAs) play crucial regulatory roles in various human diseases including cancer, making them promising biomarkers. However, given the low levels of miRNAs present in blood, their use as cancer biomarkers requires the development of simple and effective analytical methods. Herein, we report the development of a highly sensitive dual mode electrochemical platform for the detection of microRNAs. The platform was developed using peptide nucleic acids as probes on gold electrode surfaces to capture target miRNAs. A simple amplification strategy using gold nanoparticles has been employed exploiting the inherent charges of the nucleic acids. Electrochemical impedance spectroscopy was used to monitor the changes in capacitance upon any binding event, without the need for any redox markers. By using thiolated ferrocene, a complementary detection mode on the same sensor was developed where the increasing peaks of ferrocene were recorded using square wave voltammetry with increasing miRNA concentration. This dual-mode approach allows detection of miRNA with a limit of detection of 0.37 fM and a wide dynamic range from 1 fM to 100 nM along with clear distinction from mismatched target miRNA sequences. The electrochemical platform developed can be easily expanded to other miRNA/DNA detection along with the development of microarray platforms.

A comparison of isolated circulating tumor cells and tissue biopsies using whole-genome sequencing in prostate cancer

Previous studies have demonstrated focal but limited molecular similarities between circulating tumor cells (CTCs) and biopsies using isolated genetic assays. We hypothesized that molecular similarity between CTCs and tissue exists at the single cell level when characterized by whole genome sequencing (WGS). By combining the NanoVelcro CTC Chip with laser capture microdissection (LCM), we developed a platform for single-CTC WGS. We performed this procedure on CTCs and tissue samples from a patient with advanced prostate cancer who had serial biopsies over the course of his clinical history. We achieved 30X depth and ≥ 95% coverage. Twenty-nine percent of the somatic single nucleotide variations (SSNVs) identified were founder mutations that were also identified in CTCs. In addition, 86% of the clonal mutations identified in CTCs could be traced back to either the primary or metastatic tumors. In this patient, we identified structural variations (SVs) including an intrachromosomal rearrangement in chr3 and an interchromosomal rearrangement between chr13 and chr15. These rearrangements were shared between tumor tissues and CTCs. At the same time, highly heterogeneous short structural variants were discovered in PTEN, RB1, and BRCA2 in all tumor and CTC samples. Using high-quality WGS on single-CTCs, we identified the shared genomic alterations between CTCs and tumor tissues. This approach yielded insight into the heterogeneity of the mutational landscape of SSNVs and SVs. It may be possible to use this approach to study heterogeneity and characterize the biological evolution of a cancer during the course of its natural history.

Applications of circulating tumor cells for prostate cancer

One of the major challenges that clinicians face is in the difficulties of accurately monitoring disease progression. Prostate cancer is among these diseases and greatly affects the health of men globally. Circulating tumor cells (CTCs) are a rare population of cancer cells that have shed from the primary tumor and entered the peripheral circulation. Not until recently, clinical applications of CTCs have been limited to using enumeration as a prognostic tool in Oncology. However, advances in emerging CTC technologies point toward new applications that could revolutionize the field of prostate cancer. It is now possible to study CTCs as components of a liquid biopsy based on morphological phenotypes, biochemical analyses, and genomic profiling. These advances allow us to gain insight into the heterogeneity and dynamics of cancer biology and to further study the mechanisms behind the evolution of therapeutic resistance. These recent developments utilizing CTCs for clinical applications will greatly impact the future of prostate cancer research and pave the way towards personalized care for men.

Aptamer-Mediated Transparent-Biocompatible Nanostructured Surfaces for Hepotocellular Circulating Tumor Cells Enrichment

Circulating tumor cells (CTCs) have been considered as the origin of cancer metastasis. Thus, detection of CTCs in peripheral blood is of great value in different types of solid tumors. However, owing to extremely low abundance of CTCs, detection of them has been technically challenging. To establish a simple and efficient method for CTCs detection in patients with hepatocellular carcinoma (HCC), we applied biocompatible and transparent HA/CTS (Hydroxyapatite/chitosan) nanofilm to achieve enhanced topographic interactions with nanoscale cellular surface components, and we used sLex-AP (aptamer for carbohydrate sialyl Lewis X) to coat onto HA/CTS nanofilm for efficient capture of HCC CTCs, these two functional components combined to form our CTC-^BioTChip platform. Using this platform, we realized HCC CTCs' capture and identification, the average recovery rate was 61.6% or more at each spiking level. Importantly, our platform identified CTCs (2±2 per 2 mL) in 25 of 42 (59.5%) HCC patients. Moreover, both the positivity rate and the number of detected CTCs were significantly correlated with tumor size, portal vein tumor thrombus, and the TNM (tumor-node-metastasis) stage. In summary, our CTC-^BioTChip platform provides a new method allowing for simple but efficient detection of CTCs in HCC patients, and it holds potential of clinically usefulness in monitoring HCC prognosis and guiding individualized treatment in the future.

Efficient Purification and Release of Circulating Tumor Cells by Synergistic Effect of Biomarker and SiO2 @Gel-Microbead-Based Size Difference Amplification

Microfluidics-based circulating tumor cell (CTC) isolation is achieved by using gelatin-coated silica microbeads conjugated to CTC-specific antibodies. Bead-binding selectively enlarges target cell size, providing efficient high-purity capture. CTCs captured can be further released non-invasively. This stratagem enables high-performance CTC isolation for subsequent studies.

Androgen receptor targeted therapies in castration-resistant prostate cancer: Bench to clinic

The androgen receptor is a transcription factor and validated therapeutic target for prostate cancer. Androgen deprivation therapy remains the gold standard treatment, but it is not curative, and eventually the disease will return as lethal castration‐resistant prostate cancer. There have been improvements in the therapeutic landscape with new agents approved, such as abiraterone acetate, enzalutamide, sipuleucel‐T, cabazitaxel and Ra‐223, in the past 5 years. New insight into the mechanisms of resistance to treatments in advanced disease is being and has been elucidated. All current androgen receptor‐targeting therapies inhibit the growth of prostate cancer by blocking the ligand‐binding domain, where androgen binds to activate the receptor. Persuasive evidence supports the concept that constitutively active androgen receptor splice variants lacking the ligand‐binding domain are one of the resistant mechanisms underlying advanced disease. Transcriptional activity of the androgen receptor requires a functional AF‐1 region in its N‐terminal domain. Preclinical evidence proved that this domain is a druggable target to forecast a potential paradigm shift in the management of advanced prostate cancer. This review presents an overview of androgen receptor‐related mechanisms of resistance as well as novel therapeutic agents to overcome resistance that is linked to the expression of androgen receptor splice variants in castration‐resistant prostate cancer.