Methylene Blue-Stained Single-Stranded DNA Aptamers as a Highly Efficient Electronic Switch for Quasi-Reagentless Exosomes Detection: An Old Dog with New Tricks.

Improving the convenience, sensitivity, and cost-effectiveness of electrochemical biosensors is crucial for advancing their clinical diagnostic applications. Herein, we presented an elegant approach to construct electrochemical aptasensors for tumor-derived exosome detection by harnessing the alterable interaction between methylene blue (MB) and DNA aptamer. In detail, the anti-EpCAM aptamer, named SYL3C, was found to exhibit a strong affinity toward MB due to the specific interaction between MB and unbound guanine bases. Thereby, SYL3C could be stained with MB to arouse a strong electrochemical signal on a gold electrode (AuE). Upon binding to EpCAM-positive exosomes, SYL3C underwent a conformational transformation. The resulting conformation, or exosomes-SYL3C complex, not only reduced the accumulation of MB on SYL3C by obstructing the accessibility of guanines to MB but also impeded the transfer of electrons from the bound MB to AuE, leading to a notable decrease in the electrochemical signal. Using MB-stained SYL3C as an electronic switch, an electrochemical aptasensor was readily established for the detection of EpCAM-positive exosome detection. Without the need for signal amplification strategies, expensive auxiliary reagents, and complex operation, this unique signal transduction mechanism alone could endow the aptasensor with ultrahigh sensitivity. A limit of detection (LOD) of 234 particles mL-1 was achieved, surpassing the performance of most reported methods. As a proof of concept, the aptasensor was applied to analyze clinical serum samples and effectively distinguish non-small-cell lung cancer (NSCLC) patients from healthy individuals. As EpCAM exhibits broad expression in exosomes derived from different tumor sources, the developed aptasensor holds promise for diagnosing other tumor types.

Multivalent DNA Flowers for High-Performance Isolation, Detection, and Release of Tumor-Derived Extracellular Vesicles.

Tumor-derived extracellular vesicles (T-EVs) hold great promise for understanding cancer biology and improving cancer diagnostics and therapeutics. Herein, we developed multivalent DNA flowers (DFs) containing repeated and equidistant EpCAM aptamers for the efficient isolation of T-EVs. The multivalent aptamer chains in DFs had good flexibility to adapt to the surface morphology of T-EVs and achieved multivalent ligand-receptor interactions, thus showing enhanced isolation ability compared to monovalent aptamers. Compared with other materials for isolation of EVs, DFs were generated by rolling circle amplification (RCA) and self-assembled into microspheres in a one-pot reaction, and the recognition molecules (aptamers) were directly replicated and assembled during the RCA reaction instead of chemical modification and immobilization on the surface of solid materials. Moreover, as optically transparent biomaterials, the content of EpCAM+ EVs could be directly reflected via membrane-based hydrophobic assembly of signaling modules in DFs@EpCAM+ EVs complex, and we found that the amount of EpCAM+ EVs showed greater accuracy in cancer diagnosis than total EVs (88.3 vs 69.7%) and was also higher than the clinically commonly used marker carcinoembryonic antigen (CEA) (88.3 vs 76.7%). In addition, T-EVs could be released by lysis of DFs with the nuclease, gently and easily, keeping high intact and activity of EVs for downstream biological function studies. These results demonstrated that DFs are efficient and nondestructive tools for isolation, detection, and release of T-EVs.

Biomimetic Targeted Theranostic Nanoparticles for Breast Cancer Treatment.

The development of biomimetic drug delivery systems for biomedical applications has attracted significant research attention. As the use of cell membrane as a surface coating has shown to be a promising platform for several disease treatments. Cell-membrane-coated nanoparticles exhibit enhanced immunocompatibility and prolonged circulation time. Herein, human red blood cell (RBC) membrane-cloaked nanoparticles with enhanced targeting functionality were designed as a targeted nanotheranostic against cancer. Naturally, derived human RBC membrane modified with targeting ligands coated onto polymeric nanoparticle cores containing both chemotherapy and imaging agent. Using epithelial cell adhesion molecule (EpCAM)-positive MCF-7 breast cancer cells as a disease model, the nature-inspired targeted theranostic human red blood cell membrane-coated polymeric nanoparticles (TT-RBC-NPs) platform was capable of not only specifically binding to targeted cancer cells, effectively delivering doxorubicin (DOX), but also visualizing the targeted cancer cells. The TT-RBC-NPs achieved an extended-release profile, with the majority of the drug release occurring within 5 days. The TT-RBC-NPs enabled enhanced cytotoxic efficacy against EpCAM positive MCF-7 breast cancer over the non-targeted NPs. Additionally, fluorescence images of the targeted cancer cells incubated with the TT-RBC-NPs visually indicated the increased cellular uptake of TT-RBC-NPs inside the breast cancer cells. Taken together, this TT-RBC-NP platform sets the foundation for the next-generation stealth theranostic platforms for systemic cargo delivery for treatment and diagnostic of cancer.

Efficient exosome subpopulation isolation and proteomic profiling using a Sub-ExoProfile chip towards cancer diagnosis and treatment.

Exosomes have been extensively studied as liquid biopsy biomarkers in the past decade. However, the origin and molecular heterogeneity of exosomes hinder the research development moving from proof-of-concept to clinical applications. Herein, we report an integrated microfluidic platform termed Sub-ExoProfile chip, to achieve the selective isolation and subsequent proteomic profiling of multiplex exosome subpopulations simultaneously. The Sub-ExoProfile chip comprises three cylindrical self-assembled nanopillars, on which specific exosome capture antibodies (CD81, EpCAM, HER2) were immobilized to capture and sort different exosome subpopulations. It is worth noting that the 3D porous nanopillars afford enhanced interface binding efficiency; thus, a tumor-specific exosome subpopulation with lowly-expressed surface marker was still isolated with satisfactory capture efficiency. Moreover, the amphiphilic mesoporous silica nanoparticle self-assembled nanopillars also served as a nanoreactor for the enrichment and in situ digestion of exosomal proteins, providing improved performance for the mass-spectrometry based molecular characterization of exosome subpopulations. The Sub-ExoProfile chip was investigated on standard exosome samples from different breast cancer cell lines. The isolation and quantitative detection of exosome subpopulations were in line with the molecular subtype of breast cancer cell lines, and the molecular makeup was confirmed using classic microplate ELISA. Clinical samples from HER2-positive and triple-negative breast cancer patients were also examined using the Sub-ExoProfile chip. The quantitative results of three exosome subpopulations distinguished the three subtypes of breast cancer significantly. Most importantly, the molecular characterization of three exosome subpopulations revealed that the distinct exosome subpopulation participated in a different signaling pathway and performed distinct biological functions. It is envisioned that the analysis of the exosome subpopulation on the Sub-ExoProfile chip will facilitate the screening of tumor-specific exosomal biomarkers and open a new avenue for exosome-based liquid biopsy.

Integrated microfluidic-SERS for exosome biomarker profiling and osteosarcoma diagnosis.

Osteosarcoma is one of the most frequent primary sarcoma of bone among adolescents. Early diagnosis of osteosarcoma is the key factor to achieve high survival rate of patients. Nevertheless, traditional histological biopsy is highly invasive and associated with the risk of arousing tumor spread. Herein, we develop a method integrating microfluidics and surface-enhanced Raman spectroscopy (SERS) to isolate plasma-derived exosomes and profile multiple exosomal biomarkers for the diagnosis of osteosarcoma. The method showed highly efficient isolation of exosomes directly from human plasma and can profile exosomes based on protein biomarkers, with the detection limit down to 2 exosomes per µL. The whole assay can be performed in 5 h and only consumed 50 µL of plasma for one analysis. With the method, we analyzed the level of three protein biomarkers, i.e., CD63, vimentin (VIM) and epithelial cell adhesion molecule (EpCAM), on plasma-derived exosomes from 20 osteosarcoma patients and 20 heathy controls. Significantly higher levels of CD63, VIM and EpCAM were observed on plasma exosomes from the osteosarcoma patients compared to the healthy controls. Based on the level of the exosomal biomarkers, a classification model was built for the rapid diagnosis of osteosarcoma, with the sensitivity, specificity and accuracy of 100%, 90% and 95%, respectively. The proposed method does not require complex operations nor expensive equipment, and has great promise in clinical diagnosis of cancer as a liquid biopsy technique.

Hierarchical Au nanoarrays functionalized 2D Ti2CTx MXene membranes for the detection of exosomes isolated from human lung carcinoma cells.

Exosome is considered an important biomarker of liquid biopsy in early cancer screening, which can reflect the physiological and pathological status of cancer cells. Herein, we construct a novel electrochemical biosensor based on hierarchical Au nanoarray-modified 2D Ti2CTx MXene membranes for sensitive detection of exosomes. Ti2CTx MXene nanosheets were fabricated as the building blocks for preparing 2D membranes as the sensing platform via vacuum filtration. To enhance the conductivity of the MXene membrane, for the first time, hierarchical Au nanoarrays were further deposited in situ on the MXene membrane surface. The combination of MXene membrane with a large specific area and hierarchical Au nanoarrays with excellent conductivity make higher electrocatalytic and more active sites in aptamer immobilization. In this strategy, the composite membrane modified by EpCAM recognized aptamer can specifically capture target exosomes, meanwhile, these target exosomes anchor aptamer for CD63 to further enhance the sensing sensitivity and accuracy of the biosensor. As a result, the biosensor achieved high sensitivity and reliable performance for exosome sensing, with a low detection limit (58 particles/µL) in the linear range of 1 × 102 to 1 × 107 particles/µL. In addition, this biosensor showed satisfactory electrochemical stability and anti-interference ability for the detection of exosomes in real serum samples.

Proteomic alterations in extracellular vesicles induced by oncogenic PIK3CA mutations.

PIK3CA is one of the most frequently mutated genes in human cancers, with the two most prevalent activating mutations being E545K and H1047R. Although the altered intracellular signaling pathways in these cells have been described, the effect of these mutations on their extracellular vesicles (EVs) has not yet been reported. To study altered cellular physiology and intercellular communication through proteomic analysis of EVs, MCF10A cells and their isogenic mutant versions (PIK3CA E545K and H1047R) were cultured and their EVs enriched by differential ultracentrifugation. Proteins were extracted, digested with trypsin and the peptides labeled with tandem mass tag (TMT) reagents and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Four thousand six hundred and fifty-five peptides were identified from 579 proteins of which 522 proteins have been previously described in EVs. Relative quantitation revealed altered levels of EV proteins including several cell adhesion molecules. Mesothelin, E-cadherin, and epithelial cell adhesion molecule were elevated in both mutant cell-derived EVs. Markers of tumor invasion and progression like galectin-3 and transforming growth factor beta induced protein were increased in both mutants. Overall, activating mutations in PIK3CA result in altered EV composition with characteristic changes associated with these hotspot mutations.

Circulating Cancer Stem Cells Expressing EpCAM/CD90 in Hepatocellular Carcinoma: A Pilot Study for Predicting Tumor Recurrence after Living Donor Liver Transplantation.

Background/Aims: Circulating tumor cells (CTCs) with cancer stemness have been demonstrated to be a direct cause of tumor recurrence, and only few studies have reported the role of CTCs in liver transplantation (LT) for hepatocellular carcinoma (HCC). Methods: Epithelial cell adhesion molecule+ (EpCAM+), cluster of differentiation 90+ (CD90+) and EpCAM+/CD90+ CTCs were sorted via fluorescence-activated cell sorting, and transcripts level of EpCAM, K19 and CD90 in the peripheral blood were analyzed via real-time polymerase chain reaction preoperatively and on postoperative days 1 and 7 in 25 patients who underwent living donor liver transplantation (LDLT) for HCC. EpCAM protein was assessed in HCC tissue using immunohistochemical staining. The median follow-up duration was 40 months. Results: HCC after LDLT recurred in four out of 25 patients. Detection of EpCAM+ or CD90+ CTCs correlated well with their messenger RNA levels (p<0.05). EpCAM+ CTCs were readily detected in HCC tissue expressing EpCAM protein. The detection of EpCAM+ CTCs or EpCAM+/CD90+ CTCs before surgery and on postoperative day 1 was significantly associated with HCC recurrence after LT (all p<0.05). Pretransplant serum PIVKA-II >100 mAU/mL and postoperative day 1 EpCAM+/CD90+ CTCs were independent risk factors for HCC recurrence (hazard ratio, 14.64; 95% confidence interval, 1.08 to 198.20; p=0.043 and hazard ratio, 26.88; 95% confidence interval, 1.86 to 387.51; p=0.016, respectively). Conclusions: EpCAM+/CD90+ CTCs can be used preoperatively and 1 day after LDLT as key biological markers in LT candidate selection and post-LDLT management.

Photoelectrochemical assay for the detection of circulating tumor cells based on aptamer-Ag2S nanocrystals for signal amplification.

In this work, we developed a photoelectrochemical assay for circulating tumor cells (CTCs) detection based on hexagonal carbon-nitrogen tubes (HCNT) as visible light-sensitive materials. The MCF-7 cell was selected as the model CTC and was captured through specific recognition between epithelial cell adhesion molecules (EpCAM) on the cell surface and anti-EpCAM antibodies. Anti-EpCAM antibody-modified magnetic nanoparticles were used to enrich and separate MCF-7 cells from samples. The detection signal was amplified by Ag2S nanocrystals, which can compete with HCNTs for absorbing visible light, leading to a decrease of photocurrent intensity. The linear range of the assay for MCF-7 cells is from 10 to 5000 cells mL-1, with a detection limit of 3 cells mL-1 (S/D = 3). The assay has good selectivity for MCF-7 detection over HeLa cells. The assay was successfully applied for the detection of MCF-7 in human whole blood, which indicates the potential for clinical application.

MOC31 Immunostaining in the Diagnosis of Metastatic Adenocarcinoma in Serous Fluid: Special Emphasis on Atypical Cytological Cases.

BACKGROUND: The diagnosis of atypical cases in the effusion cytology sample often poses a challenge to the cytologists. AIMS AND OBJECTIVES: We evaluated the diagnostic role of MOC31 in the metastatic adenocarcinoma in effusion fluid. MATERIALS AND METHODS: The cytological examination and MOC31 immunostaining in the cell block sections were carried out in 64 cases of serous effusion. A total of 23 cases showed atypical cytology, out of which suspicious for malignancy (SFM) and atypia of undetermined significance (AUS) were 19 and 4 cases, respectively. In these cases, we also performed calretinin immunostaining. The cytological features, results of MOC31 immunostaining, and follow-up data were correlated to find out the sensitivity and specificity of MOC31 immunostaining in the diagnosis of metastatic adenocarcinoma. RESULT: The sensitivity and specificity of MOC31 were 100%. MOC31 detected all the cases of metastatic adenocarcinoma. MOC31 showed strong positivity in 19 cases of SFM. All these cases had a malignant outcome in histopathology or follow-up data. In AUS cases, MOC31 immunostaining was negative with a benign outcome. In all the atypical but malignant cases calretinin stain showed diffuse cytoplasmic and nuclear positivity. In contrast, MOC31 showed strong membranous positivity and occasionally cytoplasmic positivity. CONCLUSION: MOC31 is an excellent marker of metastatic adenocarcinoma in the serous effusion. The membranous positivity of MOC31 and negative calretinin immuno-staining are helpful in atypical cytological cases to avoid the diagnostic dilemma. The MOC31 positivity is significantly useful in discrete atypical cells which are more challenging to recognize.

A light-up fluorescence resonance energy transfer magnetic aptamer-sensor for ultra-sensitive lung cancer exosome detection.

In vitro liquid biopsy based on exosomes offers promising opportunities for fast and reliable detection of lung cancers. In this work, we present a fluorescence resonance energy transfer (FRET) magnetic aptamer-sensor for magnetic enrichment of exosomes with aptamers and detection of cancerous-surface proteins based on a light-up FRET strategy. Fluorescent quantum dots (QDs) and aptamers were introduced onto magnetic nanoparticles and the fluorescence emission turned down when the aptamers were paired with their complementary DNA on the surface of Au nanoparticles. Later, competitive binding of exosomes with the aptamers expelled the Au nanoparticles resulting in an exosome concentration-dependent linear increase of QD fluorescence intensity in a broad exosome concentration range (5 × 102-5 × 109 particles per mL). As found in our work, this system behaved ultra-sensitively and the calculated detection limit of this FRET magnetic aptamer-sensor was as low as 13 particles per mL. Furthermore, taking epithelial cancer-specific antigen (epithelial cell adhesion molecule, EpCAM) screening as a typical example, our built FRET magnetic aptamer-sensor allowed a rapid and efficient distinction of all the epithelial cancer cases (7 lung cancers and 5 other cancers) from health volunteers with 100% accuracy.

Tannic Acid (TA)-Functionalized Magnetic Nanoparticles for EpCAM-Independent Circulating Tumor Cell (CTC) Isolation from Patients with Different Cancers.

The majority of current methods of isolating circulating tumor cells (CTCs) rely on a biomarker. However, the isolation efficiency may be compromised due to the heterogeneity of CTCs. In this work, a simple and broad-spectrum method is established to efficiently isolate the heterogeneous CTCs from patient blood samples using tannic acid (TA)-functionalized magnetic nanoparticles (MNPs). The TA-functionalized MNPs (MNPs-TA) inhibit the nonspecific adhesion of peripheral blood mononuclear cell (PBMC) and enhance cancer cell capture, resulting from the unique interaction between TA and glycocalyx on cancer cells. The MNPs-TA was demonstrated to effectively capture seven kinds of cancer cells (HeLa, PC-3, T24, MAD-MB-231, MCF-7, HT1080, A549) from artificial samples (62.3-93.7%). Moreover, this epithelial cell adhesion molecule (EpCAM)-independent CTC isolation method was also tested using clinical blood samples from patients with different cancers (21 patients), which may provide a universal tool to detect CTCs in the clinic.

Highly sensitive electrochemical detection of cancer biomarker based on anti-EpCAM conjugated molybdenum disulfide grafted reduced graphene oxide nanohybrid.

An ultrasensitive, electrochemical biosensor has been fabricated by utilizing molybdenum disulfide (MoS2) grafted reduced graphene oxide (MoS2@rGO) nanohybrid as a sensing platform. Biomolecular-assisted synthetic method was adopted to synthesize MoS2@rGO nanohybrid, where L-cys was used to reduce GO. The MoS2@rGO nanohybrid exhibits improved electrochemical performance when it has been electrophoretically deposited onto the indium tin oxide (ITO) coated glass substrate. Further, epithelialcell adhesion moleculeantibodies (anti-EpCAM) specific to cancer biomarker has been covalently immobilized on the MoS2@rGO/ITO electrodes for label-free detection of EpCAM. Electrochemical results confirm that anti-EpCAM/MoS2@rGO/ITO based biosensor can detect EpCAM in the concentration range of 0.001-20 ng mL-1 with a detection limit of 44.22 fg mL-1 (S/N = 3). The biosensor's excellent analytical performance has been attributed to the efficient immobilization of EpCAM antibodies on the MoS2@rGO surface, which results in high specificity for EpCAM antigen. The fabricated biosensor showed good selectivity, reproducibility, and stability. The successful detection of EpCAM antigen in spiked samples (human saliva, serum and urine) makes this platform an alternative method for early screening of cancer biomarker.

Detection of Circulating Tumor Cells and Their Implications as a Biomarker for Diagnosis, Prognostication, and Therapeutic Monitoring in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is among the leading causes of worldwide cancer-related morbidity and mortality. Poor prognosis of HCC is attributed primarily to tumor presentation at an advanced stage when there is no effective treatment to achieve the long term survival of patients. Currently available tests such as alpha-fetoprotein have limited accuracy as a diagnostic or prognostic biomarker for HCC. Liver biopsy provides tissue that can reveal tumor biology but it is not used routinely due to its invasiveness and risk of tumor seeding, especially in early-stage patients. Liver biopsy is also limited in revealing comprehensive tumor biology due to intratumoral heterogeneity. There is a clear need for new biomarkers to improve HCC detection, prognostication, prediction of treatment response, and disease monitoring with treatment. Liquid biopsy could be an effective method of early detection and management of HCC. Circulating tumor cells (CTCs) are cancer cells in circulation derived from the original tumor or metastatic foci, and their measurement by liquid biopsy represents a great potential in facilitating the implementation of precision medicine in patients with HCC. CTCs can be detected by a simple peripheral blood draw and potentially show global features of tumor characteristics. Various CTC detection platforms using immunoaffinity and biophysical properties have been developed to identify and capture CTCs with high efficiency. Quantitative abundance of CTCs, as well as biological characteristics and genomic heterogeneity among the CTCs, can predict disease prognosis and response to therapy in patients with HCC. This review article will discuss the currently available technologies for CTC detection and isolation, their utility in the clinical management of HCC patients, their limitations, and future directions of research.

Prognostic Value of Epithelial Cell Adhesion Molecules in T1-2N0M0 Glottic Cancer.

OBJECTIVE: This is an ancillary study of a multi-institutional randomized non-inferiority phase III trial of accelerated fractionation (AF) versus standard fractionation (SF) radiation therapy for T1-2N0M0 glottic cancer (JCOG0701). Biopsy specimens of tumors from the patients enrolled in the JCOG0701 are collected and the association between clinical outcomes and histopathologic features such as expression of epithelial cell adhesion molecule (EpCAM), p53, and p16 were investigated. METHODS: Five slices of undyed slides from biopsy specimens were sent to the National Cancer Center Hospital and all the specimens were assessed for the expression of EpCAM, p53, and p16. The primary objective was to investigate the association between 3-year progression-free survival (PFS) and expression of EpCAM, p53, and p16. RESULTS: A total of 88 out of 370 patients were enrolled in this ancillary study. The 3-year PFS for tumors with strong expression of EpCAM was 70.6% (95% CI 43.1%-86.6%), while that of tumors without strong expression of EpCAM was 77.5% (95% CI 65.9%-85.5%) with no remarkable difference between groups (P = .67). Likewise, there was no significant difference in 3-year PFS between tumors regardless of p53 or p16 status. However, in a subgroup analysis for 17 patients with a strong expression of EpCAM, AF showed better 3-year PFS than SF (100% vs 54.5%, P = .07). CONCLUSIONS: From the current study, it could not be concluded that EpCAM, p16, and p53 were prognostic factors for early-stage glottic cancer after primary radiation therapy. AF might be an appropriate fractionation for tumors with a strong expression of EpCAM. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:1522-1527, 2021.

Clinicopathologic implications of epithelial cell adhesion molecule expression across molecular subtypes of breast carcinoma.

BACKGROUND: Epithelial cell adhesion molecule (EpCAM), a type I transmembrane protein of the epithelial tissues and known cell adhesion molecule, has been demonstrated to have critical role in carcinogenesis. In breast cancer, EpCAM expression has been associated with poor prognosis. The expression pattern of EpCAM across molecular subtypes of breast carcinoma has been studied in patients reporting to a South Indian multispecialty tertiary care hospital. The prognostic significance of EpCAM expression pattern and probable response to therapy has also been addressed. MATERIALS AND METHODS: EpCAM expression was assessed by immunohistochemical studies on 200 breast carcinoma tissue samples of different molecular subtypes, including luminal A, luminal B, Her2Neu, and triple-negative breast cancer (TNBC). The expression was scored using the standard scoring system. A correlation was drawn with detailed clinicopathologic annotation and available outcomes data to analyze the influence of EpCAM on prognosis. RESULTS: EpCAM expression varied significantly in the different intrinsic subtypes of breast carcinoma. Differential expression was also established with different grades of breast carcinoma with varying levels of differentiation. We observed strong EpCAM expression in TNBC among other subtypes. CONCLUSION: The differential expression of EpCAM among intrinsic subtypes of breast cancer and the correlation of EpCAM expression with high-grade breast carcinoma shown in the study have important implications in understanding the role of EpCAM and might form the basis for developing targeted therapies in breast cancer in the future.

Radionuclide Molecular Imaging of EpCAM Expression in Triple-Negative Breast Cancer Using the Scaffold Protein DARPin Ec1.

Efficient treatment of disseminated triple-negative breast cancer (TNBC) remains an unmet clinical need. The epithelial cell adhesion molecule (EpCAM) is often overexpressed on the surface of TNBC cells, which makes EpCAM a potential therapeutic target. Radionuclide molecular imaging of EpCAM expression might permit selection of patients for EpCAM-targeting therapies. In this study, we evaluated a scaffold protein, designed ankyrin repeat protein (DARPin) Ec1, for imaging of EpCAM in TNBC. DARPin Ec1 was labeled with a non-residualizing [125I]I-para-iodobenzoate (PIB) label and a residualizing [99mTc]Tc(CO)3 label. Both imaging probes retained high binding specificity and affinity to EpCAM-expressing MDA-MB-468 TNBC cells after labeling. Internalization studies showed that Ec1 was retained on the surface of MDA-MB-468 cells to a high degree up to 24 h. Biodistribution in Balb/c nu/nu mice bearing MDA-MB-468 xenografts demonstrated specific uptake of both [125I]I-PIB-Ec1 and [99mTc]Tc(CO)3-Ec1 in TNBC tumors. [125I]I-PIB-Ec1 had appreciably lower uptake in normal organs compared with [99mTc]Tc(CO)3-Ec1, which resulted in significantly (p < 0.05) higher tumor-to-organ ratios. The biodistribution data were confirmed by micro-Single-Photon Emission Computed Tomography/Computed Tomography (microSPECT/CT) imaging. In conclusion, an indirectly radioiodinated Ec1 is the preferable probe for imaging of EpCAM in TNBC.

Comparative performance of different methods for circulating tumor cell enrichment in metastatic breast cancer patients.

The isolation and analysis of circulating tumor cells (CTC) has the potential to provide minimally invasive diagnostic, prognostic and predictive information. Widespread clinical implementation of CTC analysis has been hampered by a lack of comparative investigation between different analytic methodologies in clinically relevant settings. The objective of this study was to evaluate four different CTC isolation techniques-those that rely on surface antigen expression (EpCAM or CD45 using DynaBeads® or EasySep™ systems) or the biophysical properties (RosetteSep™ or ScreenCell®) of CTCs. These were evaluated using cultured cells in order to calculate isolation efficiency at various levels including; inter-assay and inter-operator variability, protocol complexity and turn-around time. All four techniques were adequate at levels above 100 cells/mL which is commonly used for the evaluation of new isolation techniques. Only the RosetteSep™ and ScreenCell® techniques were found to provide adequate sensitivity at a level of 10 cells/mL. These techniques were then applied to the isolation and analysis of circulating tumor cells blood drawn from metastatic breast cancer patients where CTCs were detected in 54% (15/28) of MBC patients using the RosetteSep™ and 75% (6/8) with ScreenCell®. Overall, the ScreenCell® method had better sensitivity.

Predictors of recurrence and survival of hepatocellular carcinoma: A prospective study including transient elastography and cancer stem cell markers.

BACKGROUND AND STUDY AIMS: To investigate whether the measurement of liver stiffness (LSM) using fibroscan and the serum Cancer Stem Cells (CSC): Ep-CAM and cytokeratin-19, could predict the recurrence of hepatocellular carcinoma (HCC) and their impact on clinical outcome and overall survival. PATIENTS AND METHODS: This is a prospective study, including 179 HCV-related HCC patients. All patients were treated following the BCLC guidelines. All HCC patients had transient elastography, measurements of Ep-CAM and cytokeratin-19 before and six months post-treatment. We looked for predictors of recurrence and performed a survival analysis using Kaplan-Meier estimates. RESULTS: TACE was the most common procedure (77.1%), followed by microwave ablation (15.6%). Complete ablation was achieved in 97 patients; 55 of them developed HCC recurrence. After treatment, LSM increased significantly with a significant reduction in CSCs levels in complete and partial response groups. The median time to observe any recurrence was 14 months. LSM increased significantly post-treatment in patients with recurrence versus no recurrence. Higher levels of CSCs were recorded at baseline and post-treatment in patients with recurrence but without statistical significance. We used univariate analysis to predict the time of recurrence by determining baseline CK-19 and platelet levels as the key factors, while the multivariate analysis determined platelet count as a single factor. The univariate analysis for prediction of overall survival included several factors, LSM and EpCAM (baseline and post-ablation) among them, while multivariate analysis included factors such as Child score B and incomplete ablation. CONCLUSION: Dynamic changes were observed in LSM and CSCs levels in response to HCC treatment and tumour recurrence. Child score and complete ablation are factors that significantly affect survival.

Claudin-4 shows superior specificity for mesothelioma vs non-small-cell lung carcinoma compared with MOC-31 and Ber-EP4.

The distinction of malignant mesothelioma from non-small-cell lung carcinoma (NSCLC) usually requires immunohistochemistry, but some broad-spectrum carcinoma markers stain mesotheliomas, and it remains unclear which broad-spectrum markers are most valuable for distinguishing these malignancies. Here, we directly compared the sensitivity and specificity of three broad-spectrum carcinoma markers, claudin-4, Ber-EP4, and MOC-31, for distinguishing NSCLC from mesothelioma. Immunohistochemistry was performed on tissue microarrays containing 68 epithelioid mesotheliomas, 31 sarcomatoid mesotheliomas, and 147 non-small-cell lung cancers (53 adenocarcinomas, 60 squamous cell carcinomas, 13 large-cell carcinomas, and 21 sarcomatoid carcinomas). For adenocarcinoma, squamous cell carcinoma, and large-cell carcinoma, claudin-4 staining was present in 103 of 126 cases (82%), MOC-31 staining was present in 112 of 126 cases (89%), and Ber-EP4 staining was present in 113 of 126 cases (90%); these values were not statistically different. Claudin-4 stained 0 of 68 (0%), MOC-31 stained 22 of 68 (32%), and Ber-EP4 stained 24 of 68 (35%) epithelioid mesotheliomas; thus, the specificities for NSCLC versus epithelioid mesothelioma were 100%, 68%, and 65%, respectively. Claudin-4 staining was present in 7 of 21 (33%), MOC-31 staining was present in 8 of 21 (38%), and Ber-EP4 staining was present in 5 of 21 (24%) sarcomatoid carcinomas. All three markers were negative in 12 of 21 (57%) sarcomatoid carcinomas. Sarcomatoid mesotheliomas were not stained with any of these markers. We conclude that claudin-4 has considerably greater specificity and comparable sensitivity to MOC-31 and Ber-EP4 for distinguishing NSCLC from epithelioid malignant mesothelioma. The use of all three markers may be necessary for sarcomatoid neoplasms, given their limited sensitivity.