Selective capture of circulating tumor cells by antifouling nanostructure substrate made of hydrogel nanoparticles.

The detection and analysis of circulating tumor cells (CTCs) from cancer patients' blood samples present a powerful means to monitor cancer progression. In this work, an antifouling nanostructure substrate made of hydrogel nanoparticles was fabricated for an effective capture of CTCs from the blood samples. The hydrogel nanoparticles were synthesized by zwitterionic sulfobetaine methacrylate (SBMA), methacrylic acid (MAA) and N, N'-methylene bisacrylamide (MBA) through a simple polymerization. SBMA could provide an effective antifouling layer for the substrate to prevent nonspecific cell adhesion, MAA could afford active carboxyl groups for the immobilization of antibody to achieve specific CTC capture, and the nanostructured surface could improve the interaction of the target cells with the antibody modified substrate surface to enhance the capture efficiency of CTCs. Moreover, it was not necessary to further modify the antifouling molecules on the hydrogel nanoparticle substrate's surface, reducing the complexity and difficulty of the substrate preparation. The results showed that about 87 % of target cells (MCF-7 cells) were captured on the antibody modified hydrogel nanoparticle substrate. In contrast, the substrate showed little adhesive capacity for the nonspecific cells (K562 cells), and only 0.15 % of cells were captured. And 98 % of the captured cells kept good cell viability. Finally, 1-32 CTCs/mL were detected from the blood samples of five cancer patients, while no CTC was found in five healthy samples. It is envisaged that the new hydrogel nanostructure substrate is capable of capturing CTCs efficiently and specifically from patient blood samples to be used in cancer treatment.

Antifouling hydrogel-coated magnetic nanoparticles for selective isolation and recovery of circulating tumor cells.

For reliable downstream molecular analysis, it is crucially important to recover circulating tumor cells (CTCs) from clinical blood samples with high purity and viability. Herein, magnetic nanoparticles coated with an antifouling hydrogel layer based on the polymerization method were developed to realize cell-friendly and efficient CTC capture and recovery. Particularly, the hydrogel layer was fabricated by zwitterionic sulfobetaine methacrylate (SBMA) and methacrylic acid (MAA) cross-linked with N,N-bis(acryloyl)cystamine (BACy), which could not only resist nonspecific adhesion but also gently recover the captured cells by glutathione (GSH) responsiveness. Moreover, the anti-epithelial cell adhesion molecule (anti-EpCAM) antibody was modified onto the surface of the hydrogel to provide high specificity for CTC capture. As a result, 96% of target cells were captured in the mimic clinical blood samples with 5-100 CTCs per mL in 25 min of incubation time. After the GSH treatment, about 96% of the obtained cells were recovered with good viability. Notably, the hydrogel-coated magnetic nanoparticles were also usefully applied to isolate CTCs from the blood samples of cancer patients. The favorable results indicate that the hydrogel-modified magnetic nanoparticles may have a promising opportunity to capture and recover CTCs for subsequent research.

High-Efficiency Isolation and Rapid Identification of Heterogeneous Circulating Tumor Cells (CTCs) Using Dual-Antibody-Modified Fluorescent-Magnetic Nanoparticles.

Extreme rarity and inherent heterogeneity of circulating tumor cells (CTCs) result in a tremendous challenge for the CTC isolation from patient blood samples with high efficiency and purity. Current CTC isolation approaches mainly rely on the epithelial cell adhesion molecule (EpCAM), which may significantly reduce the ability to capture CTCs when the expression of EpCAM is lost or down-regulated in epithelial-mesenchymal transition. Here, a rapid and highly efficient method is developed to isolate and identify heterogeneous CTCs with high efficiency from patient blood samples using the fluorescent-magnetic nanoparticles (F-MNPs). A dual-antibody interface targeting EpCAM and N-cadherin is fabricated onto the F-MNPs to capture epithelial CTCs as well as mesenchymal CTCs from whole blood samples. The poly(carboxybetaine methacrylate) brushes of excellent antifouling properties are employed to decrease nonspecific cell adhesion. Moreover, the F-MNPs provide a prompt identification strategy for heterogeneous CTCs (F-MNPs+, Hoechst 33342+, and CD45-) that can directly identify CTCs in a gentle one-step processing within 1 h after isolation from patient blood samples. This has been demonstrated through artificial samples as well as patient samples in details.

Overexpression of ROD1 inhibits invasion of breast cancer cells by suppressing the translocation of ß-catenin into the nucleus.

The incidence of breast cancer is increasing throughout the world. Although significant progress has been made in diagnostic techniques and targeted therapies, the prognosis of breast cancer remains poor. Regulator of differentiation 1 (ROD1) may inhibit the development of several types of cancer. However, the role of ROD1 in breast cancer cells remains unknown. In the present study, western blot analysis and reverse transcription-quantitative polymerase chain reaction revealed that expression of ROD1 was significantly reduced in breast cancer cells. Overexpression of ROD1 reduced the proliferation rate, demonstrated using a Cell Counting Kit-8 assay. Additionally, the overexpression of ROD1 decreased the invasiveness of breast cancer cells, indicating that ROD1 may serve as a tumor suppressor. Additionally, the data suggested that ROD1 significantly suppressed the activity of Wnt luciferase reporter (TOP Flash) in MDA-MB-231 cells. Furthermore, it was demonstrated that ROD1 may interact with ß-catenin by using co-immunoprecipitation, resulting in suppression of ß-catenin migration into the nucleus. Notably, ROD1 demonstrated its anticancer effect by decreasing ß-catenin (Y333) phosphorylation in a nude mouse xenograft model. Overexpression of ROD1 may downregulate Ki67 protein levels, as determined by immunohistochemistry. These results indicated that ROD1 may be used as a therapeutic target in patients with breast cancer.

Plasma MicroRNA Pair Panels as Novel Biomarkers for Detection of Early Stage Breast Cancer.

Introduction: Breast cancer is the second leading cause of cancer death among females. We sought to identify microRNA (miRNA) markers in breast cancer, and determine whether miRNA expression is predictive of early stage breast cancer. The paired panel of microRNAs is promising. Methods: Global miRNA expression profiling was performed on three pooling samples of plasma from breast cancer, benign lesion and normal, using next generation sequencing technology. Thirteen microRNAs (hsa-miR-21-3p, hsa-miR-192-5p, hsa-miR-221-3p, hsa-miR-451a, hsa-miR-574-5p, hsa-miR-1273g-3p, hsa-miR-152, hsa-miR-22-3p, hsa-miR-222-3p, hsa-miR-30a-5p, hsa-miR-30e-5p, hsa-miR-324-3p, and hsa -miR-382-5p) were subsequently validated using real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR) in a cohort of 53 breast cancer, 40 benign lesions and 38 normal cases. The pairwise miRNA ratios were calculated as biomarkers to classify breast cancer. Results: According to the model used to predict breast cancer from benign lesions, a panel of five miRNA pairs had high diagnostic power with an AUC of 0.942. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of this model after 10-fold cross validation were 0.881, 0.775, 0.827, and 0.756, respectively. In addition, the other panels of miRNA pairs distinguishing the breast cancer from normal and non-cancer patients had good performance. Conclusion: Certain MicroRNA pairs were identified and deemed effective in breast cancer screening, especially when distinguishing cancer from benign lesions.

Evaluation of Plasma miR-21 and miR-152 as Diagnostic Biomarkers for Common Types of Human Cancers.

Stable blood based miRNA species have allowed for the differentiation of patients with various types of cancer. Therefore, specific blood-based miRNA might be considered as a methodology which could be informative of the presence of cancer potentially from multiple distinct organ sites. Recently, miR-21 has been identified as an "oncomir" in various tumors while miR-152 as a tumor suppressor. In this study, we investigated whether circulating miR-21 and miR-152 can be used for early detection of lung cancer (LuCa), colorectal carcinoma (CRC), breast cancer (BrCa) and prostate cancer (PCa), with distinguishing cancer from various benign lesions on these organ sites. We measured the two miRNA levels by using real-time RT-PCR in plasma samples from a total of 204 cancer patients, 159 various benign lesions, and 228 normal subjects. We observed significantly elevated expression of miR-21 and miR-152 in LuCa, CRC, and BrCa when compared with normal controls. We also found upregulation of plasma miR-21 and miR-152 levels in patients with benign lesions of lung and breast, as compared to normal controls, respectively. No significant expression variation of the two miRNAs was observed in PCa or prostatic benign lesions as compared to healthy controls. Receiver operating characteristic (ROC) analyses revealed that miR-21 and/or miR-152 can discriminate LuCa, CRC and BrCa from normal controls. Our results suggest that plasma miR-21 and miR-152 may serve as non-specific noninvasive biomarkers for early screening of LuCa, CRC, and BrCa, but not PCa.

GSTM1 null genotype is associated with increased risk of gastric cancer in both ever-smokers and non-smokers: a meta-analysis of case-control studies.

Previous studies have suggested that the glutathione S-transferases M1 (GSTM1) null genotype is associated with the risk of gastric cancer. However, the interaction between GSTM1 null genotype and smoking for the risk of gastric cancer is still elusive. Therefore, we performed a meta-analysis to ascertain this issue. Databases of PubMed, EMBASE, and China National Knowledge Infrastructure were searched to retrieve relevant studies. Smokers were categorized as "ever-smokers" and "non-smokers." Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to estimate the association strength. Subgroup analyses according to ethnicity, source of control, and sample size were also conducted. A total of 15 eligible studies, including 4,687 gastric cancer cases and 7,002 controls, were identified. We found that the GSTM1 null genotype was associated with increased risk of gastric cancer among ever-smokers (OR = 1.460, 95% CI 1.064-2.003, heterogeneity: P = 0.019). The null genotype also significantly increased the risk of gastric cancer among non-smokers (OR = 1.777, 95% CI 1.301-2.426, heterogeneity: P < 0.01). Stratified analysis according to ethnicity showed that the GSTM1 null genotype was associated with increased risk of gastric cancer among Asians both in ever-smokers (OR = 1.841, 95% CI 1.184-2.861) and non-smokers (OR = 1.773, 95% CI 1.382-2.275). In conclusion, the GSMT1 null genotype significantly increased the risk of gastric cancer both in ever-smokers and non-smokers.