Moderate expression of CD39 in GPC3-CAR-T cells shows high efficacy against hepatocellular carcinoma.

CD39 serves as a crucial biomarker for neoantigen-specific CD8+ T cells and is associated with antitumor activity and exhaustion. However, the relationship between CD39 expression levels and the function of chimeric antigen receptor T (CAR-T) cells remains controversial. This study aimed to investigate the role of CD39 in the functional performance of CAR-T cells against hepatocellular carcinoma (HCC) and explore the therapeutic potential of CD39 modulators, such as mitochondrial division inhibitor-1 (mdivi-1), or knockdown CD39 through short hairpin RNA. Our findings demonstrated that glypican-3-CAR-T cells with moderate CD39 expression exhibited a strong antitumor activity, while high and low levels of CD39 led to an impaired cellular function. Methods modulating the proportion of CD39 intermediate (CD39int)-phenotype CAR-T cells such as mdivi-1 and CD39 knockdown enhanced and impaired T cell function, respectively. The combination of mdivi-1 and CD39 knockdown in CAR-T cells yielded the highest proportion of infiltrated CD39int CAR-T cells and demonstrated a robust antitumor activity in vivo. In conclusion, this study revealed the crucial role of CD39 in CAR-T cell function, demonstrated the potential therapeutic efficacy of combining mdivi-1 with CD39 knockdown in HCC, and provided a novel treatment strategy for HCC patients in the field of cellular immunotherapy.

SIRT7 Downregulation Promotes Breast Cancer Metastasis Via LAP2α-Induced Chromosomal Instability.

Chromosomal instability (CIN) plays an important role in the initiation and progression of carcinomas. However, the regulatory mechanism of metastasis mediated by CIN in breast cancer is not fully understood. Here, we aimed to demonstrate that the deregulation of SIRT7 and lamina-associated polypeptide 2α (LAP2α) critically contributes to CIN-induced metastasis in breast cancer. Expression of SIRT7 and chromosome stability-related genes was examined using western blotting, quantitative real-time PCR, immunohistochemistry, and immunofluorescence; functional significance of SIRT7 was examined using in vitro and in vivo models; and interaction between SIRT7 and LAP2α was assessed by co-inmunoprecipitation (Co-IP) assays. Doxorubicin (DOX) inhibited SIRT7 expression and enhanced CIN in breast cancer cells; SIRT7 deficiency led to CIN in breast cancer cells. Co-IP approach and immunohistochemistry demonstrated that SIRT7 interacted directly and positively with LAP2α and SIRT7 knockdown led to increased ubiquitination-dependent degradation of LAP2α and reduced protein levels of LAP2α, whereas LAP2α knockdown did not affect SIRT7 expression. In vitro and in vivo evidence revealed that SIRT7 promotes breast cancer metastasis through the SIRT7/LAP2α axis. In summary, SIRT7 interacts with LAP2α to regulate CIN and metastasis in breast cancer, and inhibition of SIRT7/LAP2α axis represents a potential therapeutic strategy for preventing breast cancer metastasis.

TREM2+ macrophages suppress CD8+ T-cell infiltration after transarterial chemoembolisation in hepatocellular carcinoma.

BACKGROUND & AIMS: The immune landscape of hepatocellular carcinoma (HCC) following transarterial chemoembolisation (TACE) remains to be clarified. This study aimed to characterise the immune landscape following TACE and the underlying mechanism of HCC progression. METHODS: Tumour samples from five patients with treatment-naive HCC and five patients who received TACE therapy were collected and subjected to single-cell RNA sequencing. Another 22 paired samples were validated using immunofluorescence staining and flow cytometry. To clarify the underlying mechanisms, in vitro co-culture experiments and two types of TREM2-KO/WT mouse models, namely, an HCC cell orthotopic injection model and a spontaneous HCC model, were used. RESULTS: A reduced number of CD8+ T cells and an increased number of tumour-associated macrophages (TAMs) were observed in the post-TACE microenvironment. TACE therapy reduced the cluster CD8_C4, which was highly enriched with tumour-specific CD8+ T cells of pre-exhausted phenotype. TREM2 was found to be highly expressed in TAMs following TACE, which was associated with a poor prognosis. TREM2+ TAMs secreted less CXCL9 but more galectin-1 than did TREM2- TAMs. Galectin-1 promoted PD-L1 overexpression in vessel endothelial cells, impeding CD8+ T cell recruitment. TREM2 deficiency also increased CD8+ T cell infiltration, which inhibited tumour growth in both in vivo HCC models. More importantly, TREM2 deficiency enhanced the therapeutic effect of anti-PD-L1 blockade. CONCLUSIONS: This study shows that TREM2+ TAMs play an important role in suppressing CD8+ T cells. TREM2 deficiency increased the therapeutic effect of anti-PD-L1 blockade by enhancing antitumour activity of CD8+ T cells. These findings explain the reasons for recurrence and progression after TACE and provide a new target for HCC immunotherapy after TACE. IMPACT AND IMPLICATIONS: Studying the immune landscape in post-TACE HCC is important to uncover the mechanisms of HCC progression. By using scRNA sequencing and functional assays, we discovered that both the number and function of CD8+ T cells are compromised, whereas the number of TREM2+ TAMs is increased in post-TACE HCC, correlating with worse prognosis. Moreover, TREM2 deficiency dramatically increases CD8+ T cell infiltration and augments the therapeutic efficacy of anti-PD-L1 blockade. Mechanistically, TREM2+ TAMs display lower CXCL9 and increased Gal-1 secretion than do TREM2- TAMs, with Gal-1 mediating the overexpression of PD-L1 in vessel endothelial cells. These results suggest that TREM2 could be a novel immunotherapeutic target for patients treated with TACE in HCC. This provides an opportunity to break the plateau of limited therapeutic effect. This study has the value of understanding the tumour microenvironment of post-TACE HCC and thinking a new strategy of immunotherapy in the field of HCC. It is therefore of key impact for physicians, scientists and drug developers in the field of liver cancer and gastrointestinal oncology.

Pseudomonas aeruginosa detection based on droplets incubation using an integrated microfluidic chip, laser spectroscopy, and machine learning.

Pseudomonas aeruginosa is an opportunist pathogen responsible for causing several infections in the human body, especially in patients with weak immune systems. The proposed approach reports a novel pathogens detection system based on cultivating microdroplets and acquiring the scattered light signals from the incubated droplets using a microfluidic device. Initially, the microdroplets were generated and incubated to cultivate bacteria inside the microdroplets. The second part of the microfluidic chip is the detection module, embedded with three optical fibers to connect laser light and photosensors. The incubated droplets were reinjected in the detection module and passed through the laser light. The surrounding photosensors were arranged symmetrically at 45° to the flowing channel for acquiring the scattered light signal. The noise was removed from the acquired data, and time-domain waveform features were evaluated. The acquired features were trained using machine learning classifiers to classify P. aeruginosa. The k-nearest neighbors (KNN) showed superior classification performance with 95.6 % accuracy among other classifiers, including logistic regression (LR), support vector machines (SVM), and naïve Bayes (NB). The proposed research was performed to validate the method for pathogens detection with a concentration of 105 CFU/mL. The total duration of 6 h is required to test the sample, including five hours for droplets incubation and one hour for sample preparation and detection using light scattering module. The results indicate that acquiring the light scattering patterns from incubated droplets can detect P. aeruginosa using machine learning classification. The proposed system is anticipated to be helpful as a rapid device for diagnosing pathogenic infections.

Corrigendum: ASPM is a prognostic biomarker and correlates with immune infiltration in kidney renal clear cell carcinoma and liver hepatocellular carcinoma.

[This corrects the article DOI: 10.3389/fonc.2022.632042.].

ASPM Is a Prognostic Biomarker and Correlates With Immune Infiltration in Kidney Renal Clear Cell Carcinoma and Liver Hepatocellular Carcinoma.

Background: Abnormal spindle microtubule assembly (ASPM) is a centrosomal protein and that is related to a poor clinical prognosis and recurrence. However, the relationship between ASPM expression, tumor immunity, and the prognosis of different cancers remains unclear. Methods: ASPM expression and its influence on tumor prognosis were analyzed using the Tumor Immune Estimation Resource (TIMER), UALCAN, OncoLnc, and Gene Expression Profiling Interactive Analysis (GEPIA) databases. The relationship between ASPM expression and tumor immunity was analyzed using the TIMER and GEPIA databases, and the results were further verified using qPCR, western blot, and multiplex quantitative immuno fluorescence. Results: The results showed that ASPM expression was significantly higher in most cancer tissues than in corresponding normal tissues, including kidney renal clear cell carcinoma (KIRC), kidney renal papillary cell carcinoma (KIRP), liver hepatocellular carcinoma (LIHC), lung adenocarcinoma (LUAD), pancreatic adenocarcinoma (PAAD), and breast invasive carcinoma (BRCA). ASPM expression was significantly higher in late-stage cancers than in early-stages cancers (e.g., KIRC, KIRP, LIHC, LUAD, and BRCA; p < 0.05), demonstrating a possible role of ASPM in cancer progression and invasion. Moreover, our data showed that high ASPM expression was associated with poor overall survival, and disease-specific survival in KIRC and LIHC (p < 0.05). Besides, Cox hazard regression analysis results showed that ASPM may be an independent prognostic factor for KIRC and LIHC. ASPM expression showed a strong correlation with tumor-infiltrating B cells, CD8+ T cells, and M2 macrophages in KIRC and LIHC. Conclusions: These findings demonstrate that the high expression of ASPM indicates poor prognosis as well as increased levels of immune cell infiltration in KIRC and LIHC. ASPM expression may serve as a novel prognostic biomarker for both the clinical outcome and immune cell infiltration in KIRC and LIHC.

Doxorubicin-Loaded UiO-66/Bi2S3 Nanocomposite-Enhanced Synergistic Transarterial Chemoembolization and Photothermal Therapy against Hepatocellular Carcinoma.

Transcatheter arterial chemoembolization (TACE) is the first choice for patients with intermediate hepatocellular carcinoma (HCC), but clinical applications still face some problems, such as the difficulties in clearing all cancer cells and lack of targeting, which would damage normal liver cells. Recently, photothermal therapy (PTT) and nanodelivery systems have been used to improve the efficacy of TACE. However, most of these strategies achieve only a single function, and the synthesis process is complicated. Here, a simple one-step solvothermal method was used to develop multifunctional nanoparticles (UiO-66/Bi2S3@DOX), which can simultaneously achieve photothermal effects and low pH-triggered DOX release. UiO-66/Bi2S3 exhibited a pH-responsive release behavior and an excellent photothermal effect in a series of in vitro and in vivo studies. Biocompatibility was confirmed by cytotoxicity and hemocompatibility evaluations. The rat N1S1 liver tumor model was established to investigate the therapeutic effect and biosafety of the nanoplatforms using TACE. The results revealed that the combination of TACE and PTT resulted in remarkable tumor growth inhibition, and the histopathological assay further revealed extensive necrosis, downregulated angiogenesis, increased apoptosis, and proliferation in the tumor response. These results demonstrated that this nanosystem platform was a promising therapeutic agent for enhancing TACE therapy for HCC treatment.

TRIM58 inactivates p53/p21 to promote chemoresistance via ubiquitination of DDX3 in breast cancer.

Chemotherapy resistance is that the most important reason behind of carcinoma treatment failure but the underlying molecular mechanisms are unclear. Members of the tripartite motifcontaining protein (TRIM) family play crucial roles in the carcinogenesis and development of resistance against chemotherapy. Herein, we first confirmed that TRIM58 is highly expressed in triple-negative breast cancer tissues and drug-resistant MCF7/ADR cells. Furthermore, TRIM58 knockdown resulted in increased sensitivity of MCF7/ADR cells toward doxorubicin in vitro and in vivo. In contrast, TRIM58 overexpression in breast cancer cells increased doxorubicin resistance. TRIM58 was found to interact with DDX3, a protein recently reported to modulate resistance against chemotherapy. We found that TRIM58 negatively regulates DDX3 expression downstream of the P53/P21 pathway, and that DDX3 is degraded by TRIM58-mediated ubiquitination. Knockdown of DDX3 reversed doxorubicin chemotherapy sensitivity induced by TRIM58 knockdown via the P53/P21 pathway.Our study reveals that TRIM58 mediates a novel mechanism underlying the development of resistance against chemotherapy in breast cancer and provides potential targets for developing novel therapeutic targets for breast cancer.

SIRT7 interacts with TEK (TIE2) to promote adriamycin induced metastasis in breast cancer.

PURPOSE: Emerging evidence suggests that cytotoxic therapy may promote drug resistance and metastasis while inhibiting the growth of primary tumors. As yet, however, the underlying mechanisms remain unclear. Here, we aimed to investigate the pro-metastatic effects of adriamycin (ADR) therapy on breast cancer cells and to investigate the mechanisms underlying these effects. METHODS: Differentially expressed genes between MCF-7 and ADR-resistant MCF-7 breast cancer cells were identified using high-throughput RNA-seq and differential gene expression analyses. In vitro transwell and scratch wound-healing assays, and an in vivo spontaneous metastasis model were used to study the metastatic potential of the breast cancer cells. The relationship between SIRT7 and TEK expression was studied using promoter activity, electrophoretic mobility shift (EMSA), CHIP-qPCR and Co-IP assays. RESULTS: Using transcriptome sequencing, we identified two key genes (SIRT7 and TEK) that might contribute to the pro-metastatic effect of ADR on breast cancer cells. SIRT7 acted as a negative regulator for TEK by inducing deacetylation of H3K18 at the TEK promoter. Through transcription factor prediction and double fluorescence experiments, we found that EST-1 could bind to the TEK promoter. Knockdown of EST-1 removed the transcriptional inhibition of TEK that was mediated by up-regulation of SIRT7. Co-IP showed that SIRT7 interacts directly with EST-1 in breast cancer cells, indicating that SIRT7 may induce H3K18 deacetylation at the TEK promoter region by directly binding to EST-1. In vitro and in vivo results showed that overexpression of SIRT7 or inhibition of TIE2 significantly reduced ADR-dependent breast cancer cell invasion/metastasis. CONCLUSION: Our findings suggest that ADR therapy may accelerate breast cancer metastasis in a SIRT7/TEK(TIE2) dependent manner.

Tumour-Targeted and Redox-Responsive Mesoporous Silica Nanoparticles for Controlled Release of Doxorubicin and an siRNA Against Metastatic Breast Cancer.

INTRODUCTION: Metastatic breast cancer seriously harms women's health and is currently the tumour type with the highest mortality rate in women. Recently, the combinatorial therapeutic approaches that integrate anti-cancer drugs and genetic agents is an attractive and promising strategy for the treatment of metastatic breast cancer. Moreover, such a combination strategy requires better drug carriers that can effectively deliver the cargo to the breast cancer cells and achieve controlled release in the cells to achieve better therapeutic effects. METHODS: The tumour-targeted and redox-responsive mesoporous silica nanoparticles (MSNs) functionalised with DNA aptamers (AS1411) as a co-delivery system was developed and investigated for the potential against metastatic breast cancer. Doxorubicin (Dox) was loaded onto the MSNs, while AS1411 and a small interfering RNA (siTIE2) were employed as gatekeepers via attachment to the MSNs with redox-sensitive disulfide bonds. RESULTS: The controlled release of Dox and siTIE2 was associated with intracellular glutathione. AS1411 mediated the targeted delivery of Dox by increasing its cellular uptake in metastatic breast cancer, ultimately resulting in a lower IC50 in MDA-MB-231 cells (human breast cancer cell line with high metastatic potency), improved biodistribution in tumour-bearing mice, and enhanced in vivo anti-tumour effects. The in vitro cell migration/invasion assay and in vivo anti-metastatic study revealed synergism in the co-delivery system that suppresses cancer cell metastasis. CONCLUSION: The tumour-targeted and redox-responsive MSN prepared in this study are promising for the effective delivery and controlled release of Dox and siTIE2 for improved treatment of metastatic breast cancer.

Utilizing a high-throughput microdevice to study breast tumor cells clustering and metastasis.

Circulating tumor cell (CTC) clusters, which are multicellular groups of CTCs, were recently suggested to had the greater potential of forming distal metastasis than single CTCs. However, our understanding of the forming of CTC clusters is still limited since there are few existing methods to study cancer cells aggregation kinetics, especially for a small number of cells. Herein we report a high-throughput miniaturized microwell-based cell aggregation-chip (AG-chip) to enable better characterize of the tumor cells clustering process. We successfully demonstrated the capability of the AG-chip in determining cell aggregation, and found that: (1) high metastatic breast cancer cells (MDA-MB-231 & MDA-MB-436) have stronger aggregation capacities than those low metastatic breast cancer cells (MCF-7 & SK-BR-3); (2) cells with similar aggregation ability were distinguished through the analysis of aggregation kinetics; (3) the detected aggregation ability can be used to indicate the metastatic potential of the cells; (4) the inhibition of integrins could regulate the cell clustering via blockage of cell adhesion or/and cell migration. This newly developed microdevice may promote further study of CTC clusters and metastasis.

Perspectives on the Role of Histone Modification in Breast Cancer Progression and the Advanced Technological Tools to Study Epigenetic Determinants of Metastasis.

Metastasis is a complex process that involved in various genetic and epigenetic alterations during the progression of breast cancer. Recent evidences have indicated that the mutation in the genome sequence may not be the key factor for increasing metastatic potential. Epigenetic changes were revealed to be important for metastatic phenotypes transition with the development in understanding the epigenetic basis of breast cancer. Herein, we aim to present the potential epigenetic drivers that induce dysregulation of genes related to breast tumor growth and metastasis, with a particular focus on histone modification including histone acetylation and methylation. The pervasive role of major histone modification enzymes in cancer metastasis such as histone acetyltransferases (HAT), histone deacetylases (HDACs), DNA methyltransferases (DNMTs), and so on are demonstrated and further discussed. In addition, we summarize the recent advances of next-generation sequencing technologies and microfluidic-based devices for enhancing the study of epigenomic landscapes of breast cancer. This feature also introduces several important biotechnologists for identifying robust epigenetic biomarkers and enabling the translation of epigenetic analyses to the clinic. In summary, a comprehensive understanding of epigenetic determinants in metastasis will offer new insights of breast cancer progression and can be achieved in the near future with the development of innovative epigenomic mapping tools.

Extracellular vesicles engineered with valency-controlled DNA nanostructures deliver CRISPR/Cas9 system for gene therapy.

Extracellular vesicles (EVs) hold great promise for transporting CRISPR-Cas9 RNA-guided endonucleases (RNP) throughout the body. However, the cell-selective delivery of EVs is still a challenge. Here, we designed valency-controlled tetrahedral DNA nanostructures (TDNs) conjugated with DNA aptamer, and loaded the valency-controlled TDNs on EV surface via cholesterol anchoring for specific cell targeting. The targeting efficacy of different ratios of aptamer/cholesterol from 1:3 to 3:1 in TDNs on decorating EVs was investigated. TDNs with one aptamer and three cholesterol anchors (TDN1) efficiently facilitated the tumor-specific accumulation of the EVs in cultured HepG2 cells and human primary liver cancer-derived organoids, as well as xenograft tumor models. The intracellular delivery of RNP by TDN1-EVs successfully realized its subsequent genome editing, leading to the downregulation of GFP or WNT10B in specific cells. This system was ultimately applied to reduce the protein expression of WNT10B, which presented remarkable tumor growth inhibition in vitro, ex vivo and in vivo, and could be extended to other therapeutic targets. The present study provides a platform for the directional display of aptamer on surface labeling and the EVs-based Cas9 delivery, which provides a meaningful idea for future cell-selective gene editing.

A Dynamic 3D Tumor Spheroid Chip Enables More Accurate Nanomedicine Uptake Evaluation.

Nanomedicine has brought great advances for drug delivery by improving the safety and efficacy of pharmaceuticals. However, many nanomaterials showing good distribution property in vitro often display poor cellular uptake during in vivo administration. Current cellular uptake research models are mainly based on the traditional 2D culture system, which is a single layer and static system, thus the results cannot accurately reflect the distribution of nanoparticles (NPs) in vivo. In the present study, a multiple tumor culture chip (MTC-chip) is constructed to mimic solid tumor and dynamic fluid transport, in order to better study NPs penetration in vitro. Cellular uptake of mesoporous silica particles (MSNs) is evaluated using the 3D tumor spheroids on chip, and it is found that: 1) continuous administration results in larger MSNs penetration than transient administration at the same dose; 2) the size effect on cellular uptake is less significant than reported by previous in vitro studies; and 3) pretreatment with hyaluronidase (HAase) enhances the tumor penetration of large-size MSNs.

Small fluorescent albumin nanoparticles for targeted photothermal therapy via albumin-Binding protein pathways.

Targeted delivery of nanotheranostics to tumor site plays critical roles in the diagnosis and treatment of cancers, therefore, fabrication of targeted nanotheranostics has attracted increasing interest these years. Especially, nutrient transporters exhibit great prospect in the targeted delivery of nanotheranostics. However, small albumin nanoparticles which could even demonstrate more outstanding targeting ability via albumin-binding protein pathways than those nanoparticles modified with targeting ligands, have not been reported before. Herein, a facile strategy to construct small albumin nanoparticles of about 30 nm in one pot for better targeted fluorescence imaging and photothermal therapy of U87 tumors through albumin-binding protein pathways is presented. Compared with BSA-PhENH2-PPy-cRGD NPs those with a larger size but less BSA molecules on the surface, more BSA-PhENH2-PPy NPs could target the tumor site of mice in vivo, and BSA-PhENH2-PPy NPs could also demonstrate more outstanding performance in the photothermal therapy of tumors than BSA-PhENH2-PPy-cRGD NPs. This work provides a facile approach to construct small albumin nanoparticles in one pot for targeted fluorescence imaging and photothermal therapy, which also clearly proved the huge prospect of albumin nanoparticles for targeted tumor therapy via albumin-binding protein pathways.

Virus-Mimicking Cell Capture Using Heterovalency Magnetic DNA Nanoclaws.

Synergy represents a natural approach for high-efficiency recognition in biological systems. Inspired by the recognition mechanism of viral infection of mammalian cells, here we develop heterovalency magnetic DNA nanoclaws with octopus arms morphology for synergetic cell capture. We demonstrated that the rigid-flexible DNA nanoclaws can load multiple antibodies (Abs) targeting different epitopes for enhanced capture of cancer cells, especially significantly increasing the capture efficiency of MDA-MB-231 cells up to 82.3 ± 7.1%. We also employed DNA nanoclaws with the combined use of multiple Abs to capture circulating tumor cells from clinical samples with high efficiency and specificity. We expect that the DNA nanoclaws not only could play a key role in liquid biopsy, but also could be expanded, with more applications benefiting from their modularity and programmability to modify various functionalities in future.

Bioequivalence of Oral Formulations of Anastrozole in Healthy Chinese Male Volunteers: A Randomized, Single-Dose, Two-Period, Two-Sequence Crossover Study.

Anastrozole is currently used as first-line treatment in locally advanced or metastatic breast cancer. A generic anastrozole tablet was developed to offer an alternative to the marketed tablet formulation. The aim of the current study was to evaluate the bioequivalence between the test and reference formulations of anastrozole in a single-dose, 2-period, 2-sequence crossover study with a 14-day washout interval. A total of 20 healthy male Chinese volunteers were enrolled and completed the study, after oral administration of a single dose of 1.0-mg test and reference formulations of anastrozole. The blood samples were collected at different times and were determined by a fully validated high-pressure liquid chromatography-tandem mass spectrometry method. The evaluated pharmacokinetic parameters, including Cmax , AUC0-t , and AUC0-∞ , were assessed for bioequivalence based on current guidelines. The observed pharmacokinetic parameters of anastrozole of the test drug were similar to those of the reference formulation. The 90% confidence intervals of test/reference ratios for Cmax , AUC0-t , and AUC0-∞ were within the bioequivalence acceptance range of 80%-125%. The results obtained from these healthy Chinese subjects in this study suggest that the test formulation of anastrozole 1.0-mg tablet is bioequivalent to the reference formulation (Arimidex 1.0-mg tablet).

Single-Cell Mobility Analysis of Metastatic Breast Cancer Cells.

Efforts have been taken to enhance the study of single-cells, however, the task remains challenging because most previous investigations cannot exclude the interactions between single cells or separately retrieved cells with specificity for further analyses. Here, a single-cell mobility analysis platform (SCM-Chip) is developed that can not only real-time monitor single-cell migration in independent niches but can also selectively recover target cells one by one. The design of each channel with a single-cell capture unit and an outlet enables the system to place single cells in different isolated niches with fluidic capture and to respectively collect target cells based on mobilities. SCM-Chip characterization of breast cancer cells reveals the presence of high- and low-migratory populations. Whole-cell transcriptome analysis establishes that monocyte chemotactic protein induced protein 1 (MCPIP1) is related with cell mobility; cells with a high expression of MCPIP1 exhibit low mobility in vitro and metastasis in vivo. The SCM platform provides a generic tool for accurate single-cell isolation and differentiation that can be readily adapted for the study of cancer and drug development.

PEGylated chitosan nanoparticles with embedded bismuth sulfide for dual-wavelength fluorescent imaging and photothermal therapy.

It is of great significance to construct multifunctional nanosystems for simultaneous imaging and therapy of cancer cells. Herein, PEGylated chitosan nanoparticles with embedded bismuth sulfide were facilely fabricated via reverse-microemulsion method for fluorescent imaging and photothermal therapy of HepG2 cells. The obtained BSA-Bi2S3-CG-PEG nanospheres revealed dual-wavelength fluorescence, which were spectrally isolated from the bioautofluorescence. Moreover, they demonstrated remarkable photothermal conversion efficiency and stability. Importantly, these small BSA-Bi2S3-CG-PEG nanoparticles shown a zeta potential of + 42.3 mV, which could rapidly get into HepG2 cells and locate in the cytoplasm and nuclei of cells. Based on their excellent photothermal effect and high cellular uptake, BSA-Bi2S3-CG-PEG nanoparticles could efficiently kill HepG2 cells under an 808 nm laser irradiation. This construction strategy can be used for preparation of fluorescent chitosan nanoparticles with other therapeutic agents embedded, which would provide a versatile platform for dual-wavelength fluorescent imaging guided therapy of cancer.