This study presents a label-free fluorescence-based assay using a multifunctional palindromic molecular beacon (MPMB) for p53 gene detection, a crucial marker in cancer diagnosis. Compared to PCR or CRISPR-based assays, our external primer-free and isothermal strategy integrates recognition, amplification, and signaling within a single molecular design. Analytical validation revealed that the assay follows a linear response for p53 gene concentrations ranging from 0.5 nM to 200 nM, with a detection limit down to 20 pM. It features a novel application of G-triplex (G3) dimer formation with N-methyl mesoporphyrin IX (NMM), resulting in significantly enhanced fluorescence compared to traditional G3 monomer methods. The system exhibited exceptional specificity, effectively differentiating the target p53 gene from single-base mismatched sequences (MT1-MT4), and maintained robust performance in 50-fold diluted human serum with satisfactory recoveries (97.6%-101.5%). The significant advancements presented by this label-free, external primer-free, and isothermal fluorescence assay signify a major leap in molecular diagnostics. By simplifying genetic testing while maintaining high sensitivity and specificity, this method holds substantial promise for clinical practices and patient management.

Albumin-bound paclitaxel (Nab-PTX), a nanoparticle albumin-bound formulation in which paclitaxel is conjugated to human serum albumin, has emerged as a pivotal agent in cancer therapy. Its significance stems not only from direct cytotoxic effects on cancer cells but also from multifaceted interactions with angiogenesis, a critical driver of tumor progression and metastasis. Nevertheless, the underlying mechanism of its anti-angiogenesis in breast cancer remains elusive. In the present study, we employed the iTRAQ (isobaric tags for relative and absolute quantification) technique to assess the effect of Nab-PTX on Triple-negative breast cancer cells (MDA-MB-231). A total of 5145 exosomal proteins were identified, of which 941 exhibited significant differences between Nab-PTX-treated cells and the control group (P-value<0.05). Notably, we found that CYR61 (Cysteine-rich angiogenic inducer 61), a secreted matricellular protein belonging to the CCN family, was significantly inhibited by Nab-PTX. Furthermore, our study demonstrated for the first time that Nab-PTX inhibits angiogenesis via the CYR61/Integrin αvβ3 signaling pathway. These findings elucidate a potential anti-angiogenesis mechanism of Nab-PTX and highlight CYR61's promise as a therapeutic target in human breast cancer.

Chemotherapy is commonly used to treat malignant tumors. However, conventional chemotherapeutic drugs often cannot distinguish between tumor and healthy cells, resulting in adverse effects and reduced therapeutic efficacy. Therefore, zigzag-shaped gear-occlude-guided cymbal-closing (ZGC) DNA nanotechnology was developed based on the mirror-symmetry principle to efficiently construct symmetric DNA polyhedra. This nanotechnology employed simple mixing steps for efficient sequence design and assembly. A targeting aptamer was installed at a user-defined position using an octahedron as a model structure. Chemotherapeutic drug-loaded polyhedral objects were subsequently delivered into tumor cells. Furthermore, anticancer drug-loaded DNA octahedra were intravenously injected into a HeLa tumor-bearing mouse model. Assembly efficiency was almost 100 %, with no residual building blocks identified. Moreover, this nanotechnology required a few DNA oligonucleotides, even for complex polyhedrons. Symmetric DNA polyhedrons retained their structural integrity for 24 h in complex biological environments, guaranteeing prolonged circulation without drug leakage in the bloodstream and promoting efficient accumulation in tumor tissues. In addition, DNA octahedra were cleared relatively slowly from tumor tissues. Similarly, tumor growth was significantly inhibited in vivo, and a therapeutic outcome comparable to that of conventional gene-chemo combination therapy was observed. Moreover, no systemic toxicity was detected. These findings indicate the potential application of ZGC DNA nanotechnology in precision medicine.

Background: Patients with Triple-negative breast cancer (TNBC) face a poor prognosis and limited therapeutic options. Current data on eribulin usage to treat TNBC is scarce. Therefore, we sought to compare the feasibility and tolerability of eribulin-based regimens with other chemotherapy regimens in patients with TNBC.Method: This retrospective study was conducted at Fujian Medical University Cancer Hospital and included 159 patients with TNBC enrolled between October 2011 and January 2023. Patients underwent treatment with eribulin-based and other chemotherapy regimens. The study’s primary endpoints were progression-free survival (PFS) and overall survival (OS), while its secondary endpoint was objective response rate (ORR), disease control rate (DCR), and safety. Tumour response was assessed using RECIST V.1.1 criteria.Results: Of the 159 participants in the study, 42 individuals (26.4%) received treatment with eribulin, whereas 117 participants (73.6%) were administered alternative chemotherapy regimens, which included nab-paclitaxel-based therapy (n = 45) and platinum-based therapy (n = 51). The follow-up period for all patients ended on 31 December 2022, and the median follow-up time was 18.3 months (range:0.7–27.5). Following propensity score matching (PSM), eribulin-based treatment resulted in longer median progression-free survival compared to platinum-based (hazard ratio (HR) = 0.41, p = 0.006), nab-paclitaxel-based (hazard ratio = 0.36, p = 0.001) and other chemotherapy (HR = 0.39, p < 0.001). Also, eribulin induced a remarkable prolongation of the median overall survival duration in all three comparative groups. The group receiving eribulin treatment showed significantly reduced incidences of any grade of anaemia, peripheral neuropathy, nausea and vomiting, and hair loss compared to other chemotherapy groups.Conclusion: For the salvage treatment of advanced TNBC, treatment with eribulin produced longer median PFS and OS than other chemotherapy regimens, with a well-tolerated safety profile. Therefore, further investigation of eribulin-based treatment in larger randomized trials for patients with advanced TNBC is warranted.

培养一流药学人才是国家赋予药学研究生培养单位的重要使命.为适应生物医药企业对本领域药学综合素质人才的需求,福州大学开设了新药研发的跨学科知识和技能研究生课程,出版了配套教材.教学设计跨学科涵盖完整药学知识结构,致力于提升研究生科研能力及创新能力,拓宽学生视野,培养高素质复合创新型药学人才.

Electronic cigarette (e-Cig) has been promoted as a safer alternative to traditional cigarette (t-Cig) recently. However, there are limited scientific data on the potential health effects of e-Cig use. In this study, we evaluated the cytotoxicities of e-Cig and t-Cig condensate solutions (e-CigCS and t-CigCS) on human bronchial epithelial cells (16HBE cells) in vitro, and employed the exosome proteomic technique to systematically assess the effects of e-CigCS and t-CigCS on 16HBE cells. Cytotoxicity assay showed 16HBE cells were more sensitive to t-CigCS than e-CigCS. Proteomic analysis demonstrated that there are 431 differential expressed exosomal proteins (DEEPs) in test groups compared to the control air group (P-value<0.05) and t-CigCS has a greater influence than e-CigCS on exosomal protein expression. Bioinformatic analysis showed the DEEPs from the t-Cig group were significantly enriched in pathways in cancer while tobacco-flavored e-Cig (e-Cigt) and menthol-flavored e-Cig (e-Cigm) groups were not. Further validations of some DEEPs, such as NF-κB p65, Sulfiredoxin-1(SRXN1) and Thioredoxin-interacting protein (TXNIP), were carried out using immunoblot and Real-time PCR analysis, showing that t-Cig may have a greater influence than e-Cig on tumor development and metastasis. Taken together, the finding reported here strongly support our hypothesis that electronic cigarettes are significantly less toxic compared with traditional cigarette.

It remains technically challenging to develop a sensitive assay system to isothermally amplify the signal for miRNA detection because of its low abundance in tested sample, sequence similarities and existence in complex biological environments. In this study, using miRNA-21 as target model, a hairpin-inserted cross-shaped DNA nanoprobe (CP) with four functional arms is constructed for the ultrasensitive detection of miRNA via one-step built-in target analogue (BTA) cycle-mediated signal amplification. BTA is pre-locked in one arm of CP probe and inactive. In the presence of target miRNA, BTA can be unlocked and initiate an isothermal amplification process. Utilizing as-designed CP probe, miRNA-21 can be detected to down to 500 fM, and the linear response range spans over five orders of magnitude. The nonspecific signal is less than 1% upon nontarget miRNAs. CP probe exhibits ∼six times enhancement in resistance to nuclease degradation and no obvious degradation-induced fluorescence change is detected during the assay period. The recovery yield ranges from 98.2～105.5% in FBS solution. Because of the high sensitivity, desirable specificity, strong anti-interference ability and substantial increase in nuclease resistance, CP probe is a promising tool for the detection of miRNAs in a complex biological milieu.

MicroRNAs (miRNAs) are involved in a variety of biological processes, and the accurate detection of miRNAs is of great importance for early diagnosis of various cancers. Herein, we have developed a highly sensitive method for the intracellular imaging of miRNAs based on a palindromic probe-induced strand displacement amplification (pSDA). The sensing element is a partly complementary hybrid consisting of two DNA components: one fluorescent dye-labeled signaling probe containing a palindromic sequence and loop-based target recognition site and one quencher moiety-attached locking probe. In the presence of target miRNA, the target species can hybridize with the loop site and release the terminal palindromic fragment, initiating the pSDA reaction. Thus, a considerable amount of fluorescent moieties are spatially separated from the quenchers, generating a dramatically enhanced fluorescence signal. As a result, the target miRNAs can be quantified down to 25 pM with the linear response range over four orders of magnitude. The detection specificity is high enough to eliminate the interference from nontarget miRNAs and other biospecies co-existing in samples, and thus the diseased cells are easily distinguished from healthy cells. Strikingly, the pSDA-based system possesses the desirable capability to discriminate tumor cells from healthy cells, indicating a promising diagnostic tool for the detection of cancers and other diseases in early stage.

BackgroundTriple-negative breast cancer (TNBC) is the most difficult cancer to be treated. TNBC expresses high level of matricellular cysteine-rich protein CYR61/CCN1 that plays a key role in producing cancer metastases and is an important target for metastasis chemoprevention. Nitric oxide (NO) can covalently bind to the thiol group of cysteines (termed S-nitrosylation) resulting in regulation of the targeted protein functions. MethodsProtein S-nitrosylation were detected by biotin-switch assay and western blotting assay. CYR61 protein S-nitrosylated sites and 3D structure were determined by mass spectrometry and MODELLER software. Adhesion assay, cell morphology assay, wound healing assay and transwell invasion assay were used to evaluate effects of CYR61 S-nitrosylation on the cell metastatic ability. In vivo metastasis activity of CYR61 S-nitrosylation were tested by intravenous injection and mammary xenograft implantation mouse metastatic models.ResultsS-nitrosylation by GSNO of CYR61 reached a plateau quickly and was confirmed by spectroscopic analysis and biotin-switch assay. Mass-spectrometry proteomic analysis revealed that S-nitrosylation predominantly occurred at Cys100, Cys117, Cys229 and Cys239, resulting in CYR61 structure relaxed and unstable evidenced by protein structure modeling. S-nitrosylation of MDA-MB-231 cells, their CYR61-overexpressed and CYR61–silenced counterparts significantly attenuated the metastatic ability of these cells, including their ability of adhesion, mobility, invasion, and interplay with platelets, and made the adhered cells unattached. The attenuation in metastatic ability proportionally increased with the degree of S-nitrosylation to CYR61 naturally-expressed or genetically-manipulated cells, and was demonstrated in mice, where, S-nitrosylation of these cell lines not only inhibited their acute seeding to lungs after an intravenous injection, but also inhibited the late development of these cells into the metastatic nodes after mammary xenograft implantation. Furthermore, orthotopically-implanted MDA-MB-231 developed mammary tumors and later lung metastasis; whereas, the same cells with S-nitrosylation developed no tumor and metastasis at all. Conclusionwe present the first evidence that S-nitrosylation of CYR61 can significantly inhibit metastatic aggressiveness of the TNBC MDA-MB-231 cells. This conceptual creative study opens a new avenue to prevent the most aggressive TNBC from metastases by S-nitrosylation to CYR61.

Aberrant mitophagy has been implicated in a broad spectrum of disorders. PINK1, Parkin, and ubiquitin have pivotal roles in priming mitophagy. However, the entire regulatory landscape and the precise control mechanisms of mitophagy remain to be elucidated. Here, we uncover fundamental mitophagy regulation involving PINK1 and a non-canonical role of the mitochondrial Tu translation elongation factor (TUFm). The mitochondrion-cytosol dual-localized TUFm interacts with PINK1 biochemically and genetically, which is an evolutionarily conserved Parkin-independent route toward mitophagy. A PINK1-dependent TUFm phosphoswitch at Ser222 determines conversion from activating to suppressing mitophagy. PINK1 modulates differential translocation of TUFm because p-S222-TUFm is restricted predominantly to the cytosol, where it inhibits mitophagy by impeding Atg5-Atg12 formation. The self-antagonizing feature of PINK1/TUFm is critical for the robustness of mitophagy regulation, achieved by the unique kinetic parameters of p-S222-TUFm, p-S65-ubiquitin, and their common kinase PINK1. Our findings provide new mechanistic insights into mitophagy and mitophagy-associated disorders.

Successful adhesion of circulating tumor cells (CTCs) to microvascular endothelium of distant metastatic tissue is the key starting step of metastatic cascade that could be effectively chemoprevented as we demonstrated previously. Here, we hypothesize that the hetero-adhesion may produce secretory biomarkers that may be important for both premetastatic diagnosis and chemoprevention. We show that co-incubation of triple-negative breast cancer (TNBC) cell line MDA-MB-231 with human pulmonary microvascular endothelial monolayers (HPMEC) secretes Cyr61 (CCN1), primarily from MDA-MB-231. However, addition of metapristone (RU486 metabolite) to the co-incubation system inhibits Cyr61 secretion probably via the Cyr61/integrin alpha v beta 1 signaling pathway without significant cytotoxicity on both MDA-MB-231 and HPMEC. Transfection of MDA-MB-231 with Cyr61-related recombinant plasmid or siRNA enhances or reduces Cyr61 expression, accordingly. The transfection significantly changes hetero-adhesion and migration of MDA-MB-231, and the changed bioactivities by overexpressed CYR61 could be antagonized by metapristone in vitro. Moreover, the circulating MDA-MB-231 develops lung metastasis in mice, which could be effectively prevented by oral metapristone without significant toxicity. The present study, for the first time, demonstrates that co-incubation of MDA-MB-231 with HPMEC secrets CYR61 probably via the CYR61/integrin alpha(v)beta(1) signaling pathway to promote adhesion-invasion of TNBC (early metastatic step). Metapristone, by interfering the adhesion-invasion process, prevents metastasis from happening.

Herein, an autonomous table-tennis-motion-type DNA machine (ATT DNA machine) was proposed to integrate target recycling amplification (TRA) and triple strand-displacement amplification (T-SDA) into one signaling system for the efficient amplification detection of p53 gene. Firstly, X-shaped DNA duplex probe (XSP) was formed via the simple annealing of Probe A and Probe B. Upon addition of p53, the hybridization of p53 with Probe A results in the peeling of Probe B from XSP. Then, the primer binds to the Probe B to trigger a circular strand-displacement amplification, during which new primers are generated. Moreover, the newly-produced primers can in turn activate the target recycling amplification and triple strand-displacement amplification via bouncing back and forth between different Probe As and Probe Bs in a manner analogous to the table tennis motion. This newly-developed DNA machine can be used to detect p53 down to 0.5 pM with an excellent specificity, offering a 100-fold enhanced sensitivity compared to a non-amplification one-to-one hybridization based system. Moreover, this DNA machine is able to be applied for target analysis in complex environments. Additionally, the potential for practical applications is also verified, demonstrating a promising alternative tool for early diagnosis of cancers.

MicroRNAs (miRNAs) are regarded as promising cancer-related biomarkers. Here, we developed a simple, sensitive and specific fluorescence method based on the combination of rolling circle amplification (RCA) and multifunctional molecular beacon-based strand-displacement amplification (MMB-SDA) for the amplification detection of let-7a miRNA. Specifically, a multifunctional molecular beacon (MMB) was proposed to execute several functions, including the signal reporter, primer and polymerization template. To achieve RCA reaction, 3' and 5' terminal bases of padlock probe were designed as the recognition regions capable of hybridizing with let-7a miRNA. Moreover, this miRNA could serve as the primer to trigger RCA reaction after ligation, producing tens and hundreds of tandemly repeated copies of cycle. Subsequently, the RCA product hybridized with MMB and initiated the repetitive SDA reaction, opening a significant amount of MMBs and causing an amplified signal. As a result, let-7a miRNA can be specifically detected down to 51 pM, and the single-base difference between let-7a miRNAs was easily detected. The potential application was demonstrated via evaluating the let-7a miRNA level in real samples (total RNA extracted from HeLa cells). Therefore, the developed sensing strategy would provide a powerful platform for early clinical diagnostics. (c) 2017 Elsevier B.V. All rights reserved.

A perfect microenvironment facilitates the activated circulating tumor cells (CTCs) to spark the adhesion-invasion-extravasation metastatic cascade in their premetastatic niche. Platelet-CTC interaction contributes to the progression of tumor malignancy by protecting CTCs from shear stress and immunological assault, aiding CTCs entrapment in the capillary bed, enabling CTCs to successfully exit the bloodstream and enter the tissue, inducing epithelial-mesenchymal-like transition (EMT), and assisting in the establishment of metastatic foci. To prevent the cascade from sparking, we show that, the multifunctional S-nitrosocaptopril (CapNO) acts on both CTCs and platelets to interrupt platelet/CTCs interplay and adhesion to endothelium, thus inhibiting CTC-based pulmonary metastasis in vivo. The activated platelets cloak cancer HT29 cells, resulting in HT29-exhibiting platelet biomarkers CD61 and P-selectin positive. CapNO inhibits both sialyl Lewisx (Slex) expression on HT29 and ADP-induced activation of platelets through P-selectin- and GPIIb/IIIa-dependent mechanisms, confirmed by the corresponding antibody assay. CapNO inhibits platelet- or interleukin (IL)-1β-mediated adhesion between HT29 and endothelial cells, and micrometastatic formation in the lungs of immunocompetent syngeneic mouse models. CapNO have also shown the effects of vasodilation, anticoagulation, inhibition of matrix metalloproteinase-2 (MMP2) expression on cancer cells, and inhibition of cell adhesion molecules (CAMs) expression on vascular endothelium. Due to a series of the beneficial effects of CapNO, CTCs remain exposed to the hostile bloodstream environment and are vulnerable to death induced by shear stress and immune elimination. This new discovery provides a basis for CapNO used for cancer metastatic chemoprevention, and might suggest regulation of the CTCs bloodstream microenvironment as a new avenue for cancer metastatic prevention.

The sensitive detection of cancer-related genes is of great significance for early diagnosis and treatment of human cancers, and previous isothermal amplification sensing systems were often based on the reuse of target DNA, the amplification of enzymatic products and the accumulation of reporting probes. However, no reporting probes are able to be transformed into target species and in turn initiate the signal of other probes. Herein we reported a simple, isothermal and highly sensitive homogeneous assay system for tumor suppressor p53 gene detection based on a new autonomous DNA machine, where the signaling probe, molecular beacon (MB), was able to execute the function similar to target DNA besides providing the common signal. In the presence of target p53 gene, the operation of DNA machine can be initiated, and cyclical nucleic acid strand-displacement polymerization (CNDP) and nicking/polymerization cyclical amplification (NPCA) occur, during which the MB was opened by target species and cleaved by restriction endonuclease. In turn, the cleaved fragments could activate the next signaling process as target DNA did. According to the functional similarity, the cleaved fragment was called twin target, and the corresponding fashion to amplify the signal was named twin target self-amplification. Utilizing this newly-proposed DNA machine, the target DNA could be detected down to 0.1 pM with a wide dynamic range (6 orders of magnitude) and single-base mismatched targets were discriminated, indicating a very high assay sensitivity and good specificity. In addition, the DNA machine was not only used to screen the p53 gene in complex biological matrix but also was capable of practically detecting genomic DNA p53 extracted from A549 cell line. This indicates that the proposed DNA machine holds the potential application in biomedical research and early clinical diagnosis.

Malignant melanoma, the most deadly form of skin cancer, has a high propensity for metastatic spread and is notoriously chemotherapy-resistant. Metapristone is the primary metabolite of mifepristone (RU486) and shows biological activities similar to RU486. In the present study, we comprehensively investigated the efficacy of metapristone as a metastatic chemopreventive against melanoma B16F10 cells in vitro and in vivo, and evaluated the safety profile of both drugs in mice. Metapristone showed less cytostatic effect in vitro and in vivo in comparison with mifepristone. However, metapristone interfered the adhesion of B16F10 cells to fibronectin by down-regulating cellular expression of integrin α4. Chemopreventive pretreatment followed by oral administration of metapristone and mifepristone (2.5, 10, 50mg/kg/day for 35 days) to melanoma C57BL/6 mouse model showed significant attenuation of pulmonary metastatic development. Oral administration of high doses of metapristone and mifepristone to normal mice for 35 days (25, 100, 250mg/kg/day) resulted in a dose-dependent increase in mouse liver weight that was more severe with mifepristone than metapristone. The long-term toxicity study revealed more changes by mifepristone in counts of erythrocytes, leukocytes and platelets than by metapristone. In conclusion, metapristone may fit into a new class of cancer metastatic chemopreventive agents. It showed a safety and efficacy profile better than mifepristone.

Most of the present anticancer drugs are highly cytotoxic and focus mainly on killing tumor cells rather than slowing the progress of cancer metastasis. Evidence has been reported that bridges the mechanisms of inflammation and tumor invasion. Therefore, we evaluated the potency in cancer metastasis chemoprevention of compounds and a coumarin extracted from Murraya exotica, which is known for its anti-inflammation bioactivity. By carrying out experiments in vitro, we found the root extracts more efficient than the leaf extracts in restraining cell migration of MDA-MB-231 cells, while leaf extracts presented slightly stronger inhibition of tumor cell adhesion at low concentrations. In addition, compared to root extracts, a novel coumarin identified previously from root extracts showed equal inhibition on cancer cell adhesion and less inhibition on cell migration. All extracts used in this study presented low cytotoxicity in vitro. Through comparison of the contents of leaf and root extracts from M exotica, several compounds are considered promising against cancer metastasis. This study evaluates the worth of further development of M exotica to find its effect on cancer metastasis chemoprevention.

Metapristone is the most predominant biological active metabolite of mifepristone and being developed as a novel cancer metastasis chemopreventive agent by us. Despite its prominent metastasis chemopreventive effect, the underlying mechanism remains elusive. Our study, for the first time, demonstrated that metapristone had the ability to prevent breast cancer cells from migration, invasion and interfere with their adhesion to endothelial cells. To explore the underlying mechanism of metapristone, we employed the iTRAQ technique to assess the effect of metapristone on MDA-MB-231 cells. In total, 5,145 proteins were identified, of which, 311 proteins showed significant differences in metapristone-treated cells compared to the control group (P-value < 0.05). Bioinformatic analysis showed many differentially expressed proteins (DEPs) functionally associated with post-translational modification, chaperones, translation, transcription, replication, signal transduction, etc. Importantly, many of the DEPs, such as E-cadherin, vimentin, TGF-β receptor I/II, smad2/3, β-catenin, caveolin and dystroglycan were associated with TGF-β and Wnt signaling pathways, which were also linked to epithelial-to-mesenchymal transition (EMT) process. Further validation of the epithelial marker “E-caderin” and mesenchymal marker “vimetin” were carried out using immunoblot and immunofluorescence. These results have revealed a novel mechanism that metapristone-mediated metastasis chemoprevention is through intervening the EMT-related signaling pathways.

Objective: Mifepristone (RU486) is an oral first-line contraceptive used by hundreds of millions of women, and recently it was tested for anticancer activity in both genders worldwide. We are developing metapristone (the N-monodemethyl RU486) as a potential metastasis chemopreventive. The present acute and 30-d subacute toxicity study aimed at examining and compared in parallel the potential toxicity of the two drugs.Methods: The single-dose acute toxicity and 30-d subacute toxicity studies were conducted in mice and rats, respectively, by gavaging metapristone or mifepristone at various doses. Blood samples and organs were collected for blood chemistry, hematology and histology analyses.Results: Oral mifepristone (3000 mg/kg) caused 30% and 40% death in female and male mice, respectively, within 15 h post-dosing. In comparison, the same dose of metapristone produced 30% acute death in males only. Thirty-day oral administration of the two drugs to rats (12.5, 50 and 200 mg/kg/day) caused reversible hepatotoxicity that only occurred at 200 mg/kg/day group, evidenced by the elevated liver enzyme activity and liver organ weight.Conclusion: The present study, for the first time, reveals reversible hepatotoxicity in rats caused by the 30-d consecutive administration at the high dose, and warns the potential hepatotoxicity caused by long-term administrations of high doses of mifepristone or metapristone in clinical trials but not by the acute single abortion doses.

BACKGROUNDThis study was aimed at establishing a sensitive and specific isolation, characterization, and enumeration method for living circulating tumor cells (CTCs) in patients with colorectal carcinoma.METHODSQuantitative isolation and characterization of CTCs were performed through a combination of immunomagnetic negative enrichment and fluorescence‐activated cell sorting. Isolated CTCs were identified by immunofluorescence staining. The viability and purity of the sorted cells were determined by flow cytometry. Blood samples spiked with HCT116 cells (range, 3‐250 cells) were used to determine specificity, recovery, and sensitivity. The method was used to enumerate, characterize, and isolate living CTCs in 10 mL of blood from patients with colorectal carcinoma.RESULTSThe average recovery of HCT116 cells was 61% or more at each spiking level, and the correlation coefficient was 0.992. An analysis of samples from all 18 patients with colorectal carcinoma revealed that 94.4% were positive for CTCs with an average of 33 ± 24 CTCs per 10 mL of blood and with a diameter of 14 to 20 μm (vs 8‐12 μm for lymphoma). All patients were CD47+, with only 4.3% to 61.2% being CD44+. The number of CTCs was well correlated with the patient TNM stage and could be detected in patients at an early cancer stage. The sorted cells could be recultured, and their viability was preserved.CONCLUSIONSThis method provides a novel technique for highly sensitive and specific detection and isolation of CTCs in patients with colorectal carcinoma. This method complements the existing approaches for the de novo functional identification of a wide variety of CTC types. It is likely to help in predicting a patient's disease progression and potentially in selecting the appropriate treatment. Cancer 2015;121:3036–3045. © 2015 American Cancer Society.