SLAMF8, a novel biomarker for personalized immune checkpoint blockade therapy in gastrointestinal cancer

e14078

Background: Immune checkpoint inhibitors have brought great breakthroughs in cancer therapy. Activated immune response is known to be the prerequisite for exerting immunotherapy efficacy. Epstein-Barr virus (EBV) infection is associated with longer survival in gastric cancer (GC) patients due to enhanced anti-tumor immune response, and therefore it was reportedly played an important role in modulating immune checkpoint blockade therapy efficacy. However, molecular dimensions underlying the good response to immune checkpoint inhibitors in presence of EBV infection are still unclear. The aim of this study is to identify a gene signature related to EBV induced anti-tumor immune response, and select a tag gene from this signature to predict which patients are most likely to benefit from immune checkpoint blockade therapy. Methods: Two large transcriptome datasets from Gene Expression Omnibus(GEO) database (GSE51575 and GSE62254) were used to screen gene signature for EBV infected gastric cancer tissues. We further selected genes that showed a trend towards differential co-expression independent of EBV infection status. The tag gene of this differential co-expression signature was finally identified by bioinformatics analysis. To make an external validation, we performed RNA sequencing in 20 colorectal caner (CRC) tissues and 20 GC tissues, respectively. Meanwhile, tissue microarrays of CRC cohort (36 paired tumor and normal tissues) and GC cohort (75 paired tumor and normal tissues) were used to analyze the association of SLAMF8 with CD8 protein expression by immunohistochemistry (IHC). Results: Analysis of GEO datasets indicated 788 genes as feature gene cluster for EBV-positive gastric cancer, from which 290 genes were selected to be characterized by differential co-expression in either EBV-positive or EBV-negative gastric cancers. SLAMF8 was identified as the tag gene for this differential co-expression signature. This signature, tagged by SLAMF8, was successfully validated by our RNA sequencing data in presence of its good performance in dividing CRC and GC patients into two subsets. Moreover, we observed a significant association between SLAMF8 and CD8 expression in our CRC and GC tissue samples, in terms of either mRNA or protein level. Conclusions: SLAMF8, a potential indicator for T cell‐mediated immune response induced by EBV infection, may be served as a biomarker for individualized immune checkpoint blockade therapy in gastrointestinal cancer. Further SLAMF8 guided drug sensitivity tests are warranted to validate our results.

Effect of exonic microsatellite instability of B2M on the predictability of MSI/dMMR for immunotherapy

2576

Background: Microsatellite instability/mismatch repair deficiency (MSI/dMMR) has been approved as a biomarker for immune checkpoint inhibitor therapy (ICI) . However, the deficiency of mismatch repair system also caused wide-spreading insertion/deletion (indel) mutations in the exonic microsatellite sites of critical immunotherapy related genes such as β-2-macroglobulin (B2M) whose product is critical to antigen presentation. Cases of aquired resistance to ICI treatment caused by the inactivation of B2M have been reported. Therefore, we investigated the mutational profile of B2M across the MSI/dMMR high prevalent cancers such as colorectal cancer (CRC), gastric cancer (GC) and endometrial cancer (EC). Methods: FFPE tumor samples from 37 CRC, 46 GC and 25 EC patients with matched normal tissues were collected for next-generation sequencing (NGS)-based 450 genes panel assay. Genomic alterations including single base substitution, short and long insertions/deletions, copy number variations, and gene rearrangement and tumor mutational burden were assessed. Immunohistochemistry (IHC) with antibody against B2M were performed on available samples to estimate the expression and localization of these proteins. Results: Exonic microsatellite sites of B2M gene have been found instable in 51% (19/37) of CRC, 22% (10/46) of GC and 8% (2/25) of EC. MSI caused small indels at B2M coding region leads to reading frame shift and the production of nonfunctional truncated proteins. Biallelic frameshift mutations, causing non-functional proteins, were found in 47% (9/19) of CRC and 30% (3/10) of GC patients carrying Indels in B2M gene. IHC assays showed the impaired expression of B2M proteins due to frameshift mutations. In addition, NGS test confirmed concurrent mutation in B2M for a MSI-H CRC patient with primary resistance to forth-line anti-PD1 treatment. Conclusions: The extensive mutations in the coding region of genes caused by the dMMR render the cancer cell sensitive to ICI. However, the concomitant variants in exonic microsatellite sites of B2M gene may compromise the predictability of MSI/dMMR as an ICI biomarker. Biallelic mutation of B2M may cause primary resistance to ICI while the mono-allelic mutation of B2M may gain acquired resistance. Therefore, B2M status could be considered when using MSI/dMMR as a biomarker for ICI.

Gambogic acid impairs tumor angiogenesis by targeting YAP/STAT3 signaling axis

Angiogenesis is central to a wide range of physiological and pathological processes including wound healing, macular degeneration, and cancer. Excessive or inappropriate vascular supply of tumors is one of the main targets for cancer therapy. Recently, critical and selective transcriptional factors such as yes-associated protein (YAP) that control the expression of angiogenesis factors have gained increasing attention in antiangiogenic therapy. In this study, we have identified and characterized a novel inhibitor of YAP, gambogic acid (GA), which exerted striking antiangiogenic effects both in vitro and in vivo. We demonstrated that GA remarkably inhibited a variety of vascular endothelial growth factor-induced angiogenesis processes including proliferation, migration, sprouting, and tube formation of endothelial cells in vitro. In addition, GA resulted in decreased neo-vessel formation in Matrigel plugs of mice and chick chorioallantoic membrane. More importantly, we showed that GA limited tumor growth via preventing tumor angiogenesis and vascular maturation. Further mechanistic studies illustrated that GA directly targeted YAP/STAT3 signaling axis, which is critical for the transcriptional regulation of a series of angiogenic factors. Taken together, these preclinical findings suggest that GA significantly repressed tumor angiogenesis and may serve as a promising drug candidate against cancer.

KCNQ1OT1/miR-217/ZEB1 feedback loop facilitates cell migration and epithelial-mesenchymal transition in colorectal cancer

Long noncoding RNAs are widely acknowledged as a group of regulatory factors in various diseases, especially in cancers. KCNQ1 overlapping transcript 1 (KCNQ1OT1) has been reported as oncogene in human cancers. However, the role of KCNQ1OT1 in colorectal cancer (CRC) has not been fully explained. Based on the database analysis, KCNQ1OT1 was highly expressed in CRC samples and predicted the poor prognosis for CRC patients. Functional experiments revealed that KCNQ1OT1 knockdown negatively affected the proliferation, migration and epithelial-mesenchymal transition (EMT) in CRC cells. Moreover, we identified the cytoplasmic localization of KCNQ1OT1 in CRC cells, indicating the post-transcriptional regulation of KCNQ1OT1 on gene expression. Mechanism experiments including RNA Immunoprecipitation (RIP) assay and dual luciferase reporter assays verified that KCNQ1OT1 acted as a competing endogenous RNA (ceRNA) in CRC by sponging microRNA-217 (miR-217) to up-regulate the expression of zinc finger E-box binding homeobox 1 (ZEB1). Further mechanism investigation revealed that ZEB1 enhanced the transcription activity of KCNQ1OT1 by acting as a transcription activator. Finally, rescue assays were designed to demonstrate the effect of KCNQ1OT1-miR-217-ZEB1 feedback loop on proliferation, migration, and EMT of CRC cells. In brief, our research findings revealed that ZEB1-induced upregulation of KCNQ1OT1 improved the proliferation, migration and EMT formation of CRC cells via regulation of miR-217/ZEB1 axis.

First Search for Short-Baseline Neutrino Oscillations at HFIR with PROSPECT

This Letter reports the first scientific results from the observation of antineutrinos emitted by fission products of ^{235}U at the High Flux Isotope Reactor. PROSPECT, the Precision Reactor Oscillation and Spectrum Experiment, consists of a segmented 4 ton ^{6}Li-doped liquid scintillator detector covering a baseline range of 7-9 m from the reactor and operating under less than 1 m water equivalent overburden. Data collected during 33 live days of reactor operation at a nominal power of 85 MW yield a detection of 25 461±283 (stat) inverse beta decays. Observation of reactor antineutrinos can be achieved in PROSPECT at 5σ statistical significance within 2 h of on-surface reactor-on data taking. A reactor model independent analysis of the inverse beta decay prompt energy spectrum as a function of baseline constrains significant portions of the previously allowed sterile neutrino oscillation parameter space at 95% confidence level and disfavors the best fit of the reactor antineutrino anomaly at 2.2σ confidence level.

Measurement of the Electron Antineutrino Oscillation with 1958 Days of Operation at Daya Bay

We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor ν[over ¯]_{e} inverse β decay candidates observed over 1958 days of data collection. The installation of a flash analog-to-digital converter readout system and a special calibration campaign using different source enclosures reduce uncertainties in the absolute energy calibration to less than 0.5% for visible energies larger than 2 MeV. The uncertainty in the cosmogenic ^{9}Li and ^{8}He background is reduced from 45% to 30% in the near detectors. A detailed investigation of the spent nuclear fuel history improves its uncertainty from 100% to 30%. Analysis of the relative ν[over ¯]_{e} rates and energy spectra among detectors yields sin^{2}2θ_{13}=0.0856±0.0029 and Δm_{32}^{2}=(2.471_{-0.070}^{+0.068})×10^{-3}  eV^{2} assuming the normal hierarchy, and Δm_{32}^{2}=-(2.575_{-0.070}^{+0.068})×10^{-3}  eV^{2} assuming the inverted hierarchy.

Construction and analysis of dysregulated lncRNA-associated ceRNA network in colorectal cancer

Colorectal cancer (CRC) is one of the most frequently diagnosed digestive system cancer. The aim of the present study was to investigate the interactions among messenger RNAs (mRNAs), microRNAs (miRNAs), and long noncoding RNAs (lncRNAs) in CRC to reveal the mechanisms of CRC. Differentially expressed genes (DEGs) were identified from public gene expression data sets. One thousand eighty-one common dysregulated mRNAs in two data sets were identified. Gene function analysis and protein-protein interaction network analysis indicated that these DEGs might play important roles in CRC. LINC00365 was selected through coding- noncoding network analysis and its expression was validated upregulated in 22 paired clinical samples and four CRC cell lines. A competing endogenous RNA network composed of 70 miRNAs, nine mRNAs, and LINC00365 was constructed. Eight of nine mRNAs were validated upregulated in The Cancer Genome Atlas data set. Our results suggested that LINC00365 was an oncogene in CRC and it could regulate the expression of several mRNAs through sponging miRNAs.

Artificial antigen-presenting cells are superior to dendritic cells at inducing antigen-specific cytotoxic T lymphocytes

Adoptive immunotherapy is a promising cancer treatment that entails infusion of immune cells manipulated to have antitumor specificity, in vitro. Antigen-specific cytotoxic T lymphocytes are the main executors of transformed cells during cancer immunotherapy. To induce antigen-specific cytotoxic T lymphocytes, we developed artificial antigen-presenting cells (aAPCs) by engineering K562 cells with electroporation to direct the stable expression of HLA-A∗0201, CD80, and 4-1BBL. Our findings demonstrate that after three stimulation cycles, the aAPCs promoted the induction of antigen-specific cytotoxic T lymphocytes with a less differentiated "young" phenotype, which enhanced immune responses with superior cytotoxicity. This novel, easy, and cost-effective approach to inducing antigen-specific cytotoxic T lymphocytes provides the possibility of improved cancer therapies.

Should anti-EGFR mAbs be discontinued for conversion surgery in untreated right-sided metastatic colorectal cancer? A systematic review and meta-analysis

Background

Previous studies have demonstrated that left-sided tumors have better prognoses than right-sided tumors in RAS wild-type mCRC (metastatic colorectal cancer) patients, while anti-EGFR mAbs appear to have no advantage compared with bevacizumab for right-sided tumors in these patients. Nevertheless, it remains unclear whether primary tumor location affects patients’ options for potentially curative resection.

Methods

PubMed, the Cochrane Library, Embase, ASCO, and ESMO conference abstracts were searched. The inclusion criteria were RCT (randomized controlled trials) studies that evaluated the efficacy of anti-EGFR mAbs based on primary tumor location. The outcomes included ORR, ETS, and DpR. ORs for ORR were calculated with 95% confidence intervals by Comprehensive Meta-Analysis, version 2.0.

Result

Nine studies including nine RCTs were analyzed. Regardless of left- or right-sided tumors, the ORRs for anti-EGFR mAb (left-sided: 80.2%, 95% CI, 47–95%; I² = 76.9%; right-sided: 46.1%, 95% CI, 39.4–53.0%; I² = 18.9%) were both higher than the control arm including chemotherapy with or without bevacizumab. The ORs for anti-EGFR mAbs have a significant benefit compared with chemotherapy with or without bevacizumab in left-sided tumors (OR = 2.19, 95% CI, 1.41–3.38; P < 0.001). For right-sided tumors, anti-EGFR mAbs still significantly improved the ORR compared with chemotherapy alone (OR = 1.75, 95% CI, 1.05–2.90; P = 0.03), and the OR numerically favored the anti-EGFR mAbs compared with bevacizumab (OR = 1.281, 95% CI, 0.77–2.12; P = 0.335). The data of ETS and DpR from three RCTs also favored the EGFR antibody irrespective of tumor location. Resection data on differentiating tumor locations is inconclusive. For right-sided tumors, it should be noted that median PFS and OS were comparable for patients who achieved ETS in both treatment arms.

Conclusions

Anti-EGFR mAbs have advantages in the tumor shrinkage regardless of left- or right-sided tumors, which is important for conversion therapy. For right-sided tumors, anti-EGFR mAbs should remain the first choice for potentially curative resection in RAS wild-type mCRC patients. ETS may represent a subgroup of patients with right-sided tumors who might benefit from the anti-EGFR mAb.

Electronic supplementary material

The online version of this article (10.1186/s12957-018-1502-7) contains supplementary material, which is available to authorized users.

Identification of a transthyretin enhancer site that selectively binds the hepatocyte nuclear factor-3 beta isoform

The upstream proximal region of the transthyretin (TTR) promoter and a distal enhancer are sufficient to drive liver-specific expression of the TTR gene, as demonstrated by experiments in transgenic mice. Previous analyses have characterized the binding of a number of liver-enriched transcription factors of the TTR promoter including hepatocyte nuclear factors one (HNF-1), HNF-4, and three distinct HNF-3 proteins (alpha, beta, and gamma), which are members of the winged helix (fork head) family. The TTR enhancer was shown to bind members of the CCAAT/enhancer binding protein (C/EBP) family at two distinct sites (TTR-2 and TTR-3), and an oligonucleotide containing the activation protein one (AP-1) binding sequence competed for recognition to a third enhancer site (TTR-1). In this study, we have carried out a detailed analysis of the transcription factors that recognize the TTR enhancer elements (TTR-1, TTR-2, and TTR-3 oligonucleotide sequences). Analysis of the TTR-1 site demonstrates that the putative AP-1 site in the TTR enhancer binds a ubiquitously expressed factor that is distinct from the AP-1 family of proteins. Next we demonstrate, via gel shift analysis, that the TTR-3 site is recognized by the C/EBP family in liver nuclear extracts. We also show that whereas the TTR-2 enhancer site is capable of binding recombinant C/EBP proteins, it does not bind C/EBP proteins from liver nuclear extracts. The TTR-2 site does, however, contain a variant HNF-3 recognition sequence that exclusively binds the HNF-3 beta isoform. Mutation of this HNF-3 beta-specific recognition sequence caused reductions in TTR enhancer activity. We had previously observed a 95% decrease in HNF-3 alpha expression and a 20% reduction in HNF-3 beta expression in acute phase livers, which correlated with a 60% decrease in TTR gene transcription. We propose that the HNF-3 beta-specific binding site in the TTR enhancer may play a role in maintaining TTR gene expression during the acute phase response in spite of the dramatic reduction in HNF-3 alpha protein levels.

Anti-EGFR-iRGD recombinant protein modified biomimetic nanoparticles loaded with gambogic acid to enhance targeting and antitumor ability in colorectal cancer treatment

Background

Red blood cell membrane-coated nanoparticle (RBCm-NP) platform, which consist of natural RBCm and synthetic polymeric core, can extend circulation time in vivo with an improved biocompatibility and stability of this biomimetic nanocarrier. To achieve better bioavailability of antitumor drugs that were loaded in RBCm-NPs, the functionalization of coated RBCm with specific targeting ability is essential. Bispecific recombinant protein anti-EGFR-iRGD, containing both tumor penetrating peptide (internalizing RGD peptide) and EGFR single-domain antibody (sdAb), seems to be an optimal targeting ligand for RBCm-NPs in the treatment of multiple tumors, especially colorectal cancer with high EGFR expression.

Materials and methods

We modified the anti-EGFR-iRGD recombinant protein on the surface of RBCm-NPs by lipid insertion method to construct iE-RBCm-PLGA NPs and confirmed the presentation of active tumor-targeting ability in colorectal cancer models with high EGFR expression when compared with RBCm-PLGA NPs. In addition, potential anti-tumor drug gambogic acid (GA) was loaded into the NPs to endow the antitumor efficiency of iE-RBCm-GA/PLGA NPs. It was simultaneously evaluated whether GA can reach better biocompatibility benefiting from the improved antitumor efficiency of iE-RBCm-GA/PLGA NPs in colorectal cancer models.

Results

We successfully modified anti-EGFR-iRGD proteins on the surface of biomimetic NPs with integrated and stable "shell-core" structure. iE-RBCm-PLGA NPs showed its improved targeting ability in vitro (multicellular spheroids [MCS]) and in vivo (nude mice bearing tumors). Besides, no matter on short-term cell apoptosis at tumor site (terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling [TUNEL]) and long-term tumor inhibition, iE-RBCm-GA/PLGA NPs achieved better antitumor efficacy than free GA in spite of the similar effects of cytotoxicity and apoptosis to GA in vitro.

Conclusion

We expect that the bispecific biomimetic nanocarrier can extend the clinical application of many other potential antitumor drugs similar to GA and become a novel drug carrier in the colorectal cancer treatment.

Measurement of circulating tumor cells in squamous cell carcinoma of the head and neck and patient outcomes

OBJECTIVES

We report the outcomes of patients with squamous cell carcinoma of the head and neck (HNSCC) whose circulating tumor cells (CTCs) were quantified using surface-enhanced Raman scattering (SERS) nanotechnology.

METHODS

SERS tagged with EGF was used to directly measure targeted CTCs. Patient charts were retrospectively reviewed. An optimal cut point for CTCs in 7.5 ml of peripheral blood predictive of for distant metastasis-free survival (DMFS) was identified by maximizing the log-rank statistic. An ROC analysis was also performed.

RESULTS

Of 82 patients, 13 experienced metastatic progression. The optimal cut point for DMFS was 675 CTCs (p = 0.047). For those with distant recurrence (n = 13) versus those without distant recurrence (n = 69), the CTC cut point which results in the largest combined sensitivity and specificity values is also 675 (sensitivity = 69%, specificity = 68%).

CONCLUSION

Liquid biopsy techniques in HNSCC show promise as a means of identifying patients at greater risk of disease progression.

Gambogic acid regulates the migration and invasion of colorectal cancer via microRNA-21-mediated activation of phosphatase and tensin homolog

Gambogic acid (GA) has been reported to inhibit cancer cell proliferation and migration and enhance apoptosis. Several signaling pathways were identified to be involved in GA function, including PI3K/Akt, caspase-3 apoptosis and TNF-α/NF-κB. However, to the best of our knowledge, the association between miRNA and GA has not been explored. The present study initially demonstrated that GA could inhibit HT-29 cancer cell proliferation using an MTT assay. In addition, a Transwell assay and a wound-healing assay respectively indicated that GA inhibited HT-29 cancer cell invasion and migration, which was also confirmed by the increased MMP-9 protein expression. Furthermore, GA induced the apoptosis of HT-29 cancer cells in an Annexin V and PI double staining assay. Moreover, treatment with GA significantly decreased miR-21 expression in these cells. Additionally, western blot analysis demonstrated that GA treatment enhanced the activation of phosphatase and tensin homolog (PTEN) along with the suppression of PI3K and p-Akt. Furthermore, miR-21 mimics reversed all the aforementioned activities of GA, which indicated that miR-21 was the effector of GA and blocked PI3K/Akt signaling pathway via enhancing PTEN activity. In summary, GA induced HT-29 cancer cell apoptosis via decreasing miR-21 expression and blocking PI3K/Akt, which may be a useful novel insight for future CRC treatment.

Differences in teachers verbal responsiveness to groups of children with ASD who vary in cognitive and language abilities

BACKGROUND

This study aimed to examine whether verbal responsiveness in special education teachers varied among subgroups of children with autism spectrum disorder (n = 112) who differed in cognitive and language abilities.

METHODS

Participants were divided into clusters using cluster analysis based on standardised cognitive and language tests using k-mean clustering. For each child, a 15-min video of free play in school setting was collected. Three types of responsive utterances were coded: follow-in directives for behaviour, follow-in directives for language and follow-in comments.

RESULTS

Results showed that the three groups did not differ in overall verbal responsiveness after controlling for engagement, classroom type, age and gender. However, groups differ in follow-in directives for language, but not in follow-in directives for behaviours or follow-in comments. Compared with children with autism spectrum disorder who had higher cognitive and language ability, children with more severe impairments received fewer follow-in directives for language. Moreover, children with more cognitive and language impairments produced fewer amount of vocal/verbal acts, which results in receiving fewer verbal responses from their teachers. Additionally, teachers from the three groups did not differ in their responses to the child's verbal/vocal acts when the number of the child's verbal/vocal acts were controlled for.

CONCLUSION

Findings suggest child characteristics are related to the type of teachers' verbal responses in preschools. This difference in follow-in directives for questions may be related to language or other outcomes that warrant further investigations.

The plasma levels of 12 cytokines and growth factors in patients with gastric cancer

To assess the association of plasma cytokines and growth factor levels with clinical characteristics and inflammatory indices in patients with gastric cancer.Plasma samples derived from 99 gastric cancer patients were used for analysis. Levels of interferon (IFN)-γ, tumor growth factor (TGF)-β1, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, IL-12p70, and vascular endothelial growth factor (VEGF) were measured by Luminex suspension array technology. The association between cytokine/growth factor levels and demographic/clinical characteristics was assessed. Correlation between cytokines and growth factor levels was assessed by Pearson's correlation analysis.Male patients had significant higher levels of plasma TNF-α, IL-12p70, IL-4, IL-10, and VEGF as compared with those in women (P < .05). Plasma levels of TNF-α in older patients with gastric cancer (≥60 years) were higher than those in young patients (P < .05). Elevated plasma levels of IL-8 and IL-10 were identified as risk factors for increased tumor size (diameter ≥5 cm). Higher plasma levels of TGF-β1 were associated with increased risk of vascular or nerve invasion and advanced tumor stage. The levels of systemic inflammatory markers, including white blood cell counts, neutrophil/lymphocyte proportion, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio (PLR), C-reactive protein and modified Glasgow prognostic score (mGPS) were closely associated with a series of plasma cytokines. A prominent correlation was observed between the plasma IL-12p70 and IFN-γ levels (r = 0.729, P < .01).Our findings suggest that plasma cytokines and growth factor levels may help predict the development and progression of gastric cancer. Our findings need to be validated by larger studies.

Use of simultaneous radiation boost achieves high treatment response rate in patients with metastatic gastric cancer

Objective

Intensity-modulated radiation therapy (IMRT) with a simultaneous integrated boost (SIB) could improve local control rates at different anatomic sites. However, little is known for its use in metastatic gastric cancer. Our study aimed to compare the treatment response rates of IMRI-SIB and conformal radiotherapy (CRT) in patients with metastatic gastric cancer.

Materials and Methods

We retrospectively identified twenty patients with metastatic gastric cancer from 2013 to 2015, 12 given IMRT-SIB, and eight given CRT. Treatment response and toxicities were evaluated for all patients. The radiation target included peritoneal lymph nodes. RECIST criteria were used to assess the treatment response. Three patients of eight in the CRT group died before the end of treatment due to the progression of diseases in the field.

Results

For the IMRT-SIB group, the median dose of high dose field was 60.8 Gy (50-64.4 Gy), and the median dose of low-dose field was 45 Gy (36-50.4 Gy). For the CRT group, the median dose of the total dose was 50 Gy (41.4-60 Gy). IMRT-SIB could elevate local dose significantly, compared to the CRT group. One patient of 12 in the IMRT-SIB group achieved complete response, and nine patients achieved partial response (PR), whereas no patient achieved CR in the CRT group. Two of five patients achieved PR (40%) in the CRT group. IMRT-SIB improved the treatment response rate significantly (odds ratio 8.33, 95% confidence interval: 1.03-67.14, P = 0.046). Two patients of 12 in the IMRT-SIB group developed enteritis, whereas two patients of five developed enteritis in the CRT group.

Conclusions

IMRT-SIB could escalate the local dose and improve the treatment response rates in patients with metastatic gastric cancer and with acceptable toxicities. Further study with a larger population to validate our data is underway.

FOLFOX plus anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb) is an effective first-line treatment for patients with RAS-wild left-sided metastatic colorectal cancer: A meta-analysis

BACKGROUND

The efficacy of oxaliplatin-based chemotherapy combined with anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb) remains controversial in metastatic colorectal cancer (mCRC). This meta-analysis aims to estimate the effect of adding panitumumab or cetuximab to oxaliplatin-based chemotherapy in RAS wild type mCRC patients for the first-line treatment. The primary tumor location is also considered into this meta-analysis.

METHODS

RCT studies were identified by a search of MEDLINE, EMBASE, Cochrane library to October 2017, supplemented by manually retrieving ASCO, ESMO conference abstracts. The pooled hazard ratio (HR) for progression-free survival (PFS) and overall survival (OS), and pooled odds ratios (OR) for the overall response rate (ORR) were calculated by Review Manager 5.3.

RESULTS

The results indicated that the addition of anti-EGFR mAbs to FOLFOX regimen in RAS wild-type mCRC patients for the first-line treatment resulted in considerable improvements in PFS (HR = 0.70; 95% confidence interval [CI]: 0.59-0.82; P < .0001), OS (HR = 0.79; 95%CI: 0.67-0.92; P = .003), and ORR (OR = 2.56; 95% CI: 1.77-3.70; P < .00001) compared with chemotherapy alone. However, in RAS/BRAF wild patients, no significant differences were observed when anti-EGFR mAb was added to FLOX or XELOX regimen compared with chemotherapy alone with regard to OS and PFS, whereas FOLFOX+anti-EGFR mAb showed a marked superior OS and PFS (OS, HR = 0.77; 95% CI: 0.61-0.98; P = .03; PFS, HR = 0.68; 95% CI: 0.57-0.82; P < .00001). A meta-analysis including TAILOR and PRIME study suggests that primary tumor location (PTL) predicted a survival benefit when adding the EGFR antibody to FOLFOX regimen in RAS-wild mCRC patients (OS, HR for left-sided: 0.71; 95% CI: 0.59-0.85; P = .0002 and HR for right-sided: 0.90; 95% CI: 0.65-1.25; P = .53). However, the HR for PFS and ORR still suggests a benefit from the addition of anti-EGFR mAb in right-sided mCRC patients.

CONCLUSION

So these results suggest anti-EGFR mAb and oxaliplatin are good partners in the FOLFOX regimen. The addition of EGFR antibody to FOLFOX markedly improved efficacy in RAS-wild patients with left-sided mCRC. In RAS/BRAF-wild patients, the efficacy is similar. For patients with right-sided tumor, a benefit showing a trendency in favor of anti-EGFR mAb can still seen. The molecular characteristics behind the tumor location need to be more explored urgently.

The Pandora multi-algorithm approach to automated pattern recognition of cosmic-ray muon and neutrino events in the MicroBooNE detector

The development and operation of liquid-argon time-projection chambers for neutrino physics has created a need for new approaches to pattern recognition in order to fully exploit the imaging capabilities offered by this technology. Whereas the human brain can excel at identifying features in the recorded events, it is a significant challenge to develop an automated, algorithmic solution. The Pandora Software Development Kit provides functionality to aid the design and implementation of pattern-recognition algorithms. It promotes the use of a multi-algorithm approach to pattern recognition, in which individual algorithms each address a specific task in a particular topology. Many tens of algorithms then carefully build up a picture of the event and, together, provide a robust automated pattern-recognition solution. This paper describes details of the chain of over one hundred Pandora algorithms and tools used to reconstruct cosmic-ray muon and neutrino events in the MicroBooNE detector. Metrics that assess the current pattern-recognition performance are presented for simulated MicroBooNE events, using a selection of final-state event topologies.

miR‑1273g‑3p promotes proliferation, migration and invasion of LoVo cells via cannabinoid receptor 1 through activation of ERBB4/PIK3R3/mTOR/S6K2 signaling pathway

MicroRNAs (miR) are important in various crucial cell processes including proliferation, migration and invasion. Dysregulation of miRNAs have been increasingly reported to contribute to colorectal cancer. However, the detailed biological function and potential mechanisms of miR‑1273g‑3p in colorectal cancer remain poorly understood. The expression levels of miR‑1273g‑3p in human colorectal cancer LoVo cell lines were detected via reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). The target genes of miR‑1273g‑3p were predicted by bioinformatics and verified by a luciferase reporter assay, RT‑qPCR and western blotting. The MTT, wound‑healing and Transwell assays were used to examine the biological functions of miR‑1273g‑3p in LoVo cells. The potential molecular mechanisms of miR‑1273g‑3p on LoVo cell proliferation, migration and invasion was detected by western blotting. The results of the present study demonstrated that miR‑1273g‑3p expression was extensively upregulated in LoVo cells compared with the normal colon epithelial NCM460 cell line. Further studies indicated that miR‑1273g‑3p inhibitor significantly suppressed LoVo cell proliferation, migration and invasion compared with inhibitor control. Following this, the cannabinoid receptor 1 (CNR1) was identified as a direct target gene of miR‑1273g‑3p. Knockdown of CNR1 restored the phenotypes of LoVo cells transfected with miR‑1273g‑3p inhibitor. Furthermore, the potential molecular mechanism of miR‑1273g‑3p on LoVo cell proliferation, migration and invasion may be mediated by activating the Erb‑B2 receptor tyrosine kinase 4 (ERBB4)/phosphoinositide‑3‑kinase regulatory subunit 3 (PIK3R3)/mechanistic target of rapamycin (mTOR)/S6 kinase 2 (S6K2) signaling pathway. These observations indicated that miR‑1273g‑3p promoted the proliferation, migration and invasion of LoVo cells via CNR1, and this may have occurred through activation of the ERBB4/PIK3R3/mTOR/S6K2 signaling pathway, suggesting that miR‑1273g‑3p may serve as a novel therapeutic target for the effective treatment of colorectal cancer.

Use of Pulsed Low-Dose Rate Radiotherapy in Refractory Malignancies

BACKGROUND

Most tumor cell lines exhibited low-dose hyperradiosensitivity (LDHRS) to radiation doses lower than 0.3 Gy. Pulsed low-dose rate radiotherapy (PLDR) took advantage of LDHRS and maximized the tumor control process. In this study, we retrospectively analyzed patients receiving PLDR for refractory malignancies.

PATIENTS AND METHODS

In total, 22 patients were included in our study: 9 females and 13 males. The median age was 61 years old. All the patients previously received multiline treatments and failed with an estimated survival less than 6 months. Thus, palliative PLDR was given. The PLDR was delivered using 10 fractions of 2 Gy/day, with an interval of 3 minutes, for 5 days per week. The dose rate was 6.67 cGy/min. The median follow-up was 1 year (range 8-30 months). Nine patients underwent PLDR for reirradiation due to locally recurrent diseases. The time interval from last irradiation was 11 to 168 months. Ten patients received PLDR due to poor performance status. Three patients were given PLDR for bulky tumor. The irradiated sites included primary disease (seven patients), locally recurrent disease (nine patients), and retroperitoneal adenopathy (six patients).

RESULTS

Five patients developed grade 3 or 4 toxicities. No grade 5 toxicities occurred. All the toxicities recovered after treatments. In general, the 1-year local-regional control rate was approximately 40%, and almost all the patients developed progression at the second year after PLDR. The 6-month survival rate was 76%, and the 1-year survival rate was 69%. For the three patients given PLDR for bulky tumor, all of them achieved partial remission 1 month after the PLDR, and one patient achieved complete response at the fourth month.

CONCLUSION

PLDR is an effective and safe option not only for reirradiation but also for patients with poor performance status or bulky tumors. A prospective clinical trial (NCT03061162) is ongoing to validate our results.

Bispecific tumor-penetrating protein anti-EGFR-iRGD efficiently enhances the infiltration of lymphocytes in gastric cancer

Efficient trafficking of lymphocytes to the tumor microenvironment is crucial for the success of an effective antitumor immunotherapy. A major challenge to achieve effective adoptive immunotherapy is poor tumor penetration and inefficient migration of T cells to the tumor site. Several approaches to facilitate the trafficking of lymphocytes to the tumor microenvironment have been suggested to overcome these obstacles. Here, we address this issue with a focus on the tumor-penetrating peptide iRGD, which can specifically increase the permeability of the tumor vasculature and tumor tissue, enhancing drug penetration. We previously constructed a bispecific tumor-penetrating protein, anti-EGFR-iRGD, which consists of the variable region of the heavy chain of anti-EGFR antibody and a tumor-penetrating peptide iRGD, and verified its ability to improve the penetration of antitumor drugs. Herein, we introduce a novel method of co-administering T cells and anti-EGFR-iRGD to enhance the trafficking, penetration and antitumoral activity of T cells. Our results provide new insights for effectively enhancing T-cell infiltration in tumors and demonstrate a preclinical translational approach for the use of anti-EGFR-iRGD as a therapeutic modifier of cancer immunotherapy to improve clinical outcomes.

Cancer/testis Antigen MAGEA3 Interacts with STAT1 and Remodels the Tumor Microenvironment

Cancer-testis antigen MAGEA3, being restrictedly expressed in testis and various kinds of tumors, has long been considered as an ideal target for immunotherapy. In this study, we report that MAGEA3 interacts with STAT1 and regulates the expression of tyrosine phosphorylated STAT1 (pY-STAT1) in tumor cells. We show that pY-STAT1 is significantly up-regulated when MAGEA3 is silenced by MAGEA3-specific siRNA. RNA sequencing analysis identified 274 STAT1-related genes to be significantly altered in expression level in MAGEA3 knockdown cells. Further analysis of these differentially expressed genes with GO enrichment and KEGG pathway revealed that they are mainly enriched in plasma membrane, extracellular region and MHC class I protein complex, and involved in the interferon signaling pathways, immune response, antigen presentation and cell chemotaxis. The differentially expressed genes associated with chemokines, antigen presentation and vasculogenic mimicry formation were validated by biological experiments. Matrigel matrix-based tube formation assay showed that silencing MAGEA3 in tumor cells impairs tumor vasculogenic mimicry formation. These data indicate that MAGEA3 expression in tumor cells is associated with immune cells infiltration into tumor microenvironment and anti-tumor immune responses, implying that it may play an important role in tumor immune escape. Our findings reveal the potential impact of MAGEA3 on the immunosuppressive tumor microenvironment and will provide promising strategies for improving the efficacy of MAGEA3-targeted immunotherapy.

Low dose irradiation increases adoptive cytotoxic T lymphocyte migration in gastric cancer

Adoptive cellular immunotherapy (ACI) has been demonstrated to be a promising cancer therapeutic; however, the inefficient migration of adoptive immune cells to tumors is one of the rate-limiting factors of ACI. The present study investigated whether 2 Gy low dose irradiation (LDI) was able to increase the migration of adoptive lymphocytes to gastric cancer cells. Treatment with 2 Gy LDI resulted in marked chemokine (C-X-C motif) ligand 9 (CXCL9) and CXCL10 production from gastric cancer cell lines. A Transwell chamber migration assay demonstrated enhanced transmigration of cytotoxic T lymphocytes to gastric cancer cells following LDI treatment. After 2 Gy LDI application to established gastric carcinoma in nude mice, labeled immune cells were infused by intravenous injection and concentrated fluorescence signals were observed at the tumor sites within the mice, with a peak signal at 8-h LDI. Increased numbers of adoptive T cells at the tumor sites were also observed using flow cytometry. Furthermore, a case study of a patient with metastatic gastric cancer who had received ACI treatment combined with 2 Gy LDI provided further evidence that 2 Gy LDI is able to recruit antitumor effector T cells to tumor sites. Therefore, the ability of 2 Gy LDI to convert tumors into inflamed peripheral tissues may be exploited to overcome obstacles at the effector phase of the antitumor immune response and improve the therapeutic efficacy of immunotherapy.

Publisher's Note: JLab Measurements of the ^{3}He Form Factors at Large Momentum Transfers [Phys. Rev. Lett. 119, 162501 (2017)]

This corrects the article DOI: 10.1103/PhysRevLett.119.162501.

JLab Measurements of the ^{3}He Form Factors at Large Momentum Transfers

The charge and magnetic form factors, F_{C} and F_{M}, respectively, of ^{3}He are extracted in the kinematic range 25  fm^{-2}≤Q^{2}≤61  fm^{-2} from elastic electron scattering by detecting ^{3}He recoil nuclei and scattered electrons in coincidence with the two High Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The measurements find evidence for the existence of a second diffraction minimum for the magnetic form factor at Q^{2}=49.3  fm^{-2} and for the charge form factor at Q^{2}=62.0  fm^{-2}. Both minima are predicted to exist in the Q^{2} range accessible by this Jefferson Lab experiment. The data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the three-body nuclear problem.

5-Hydroxymethylcytosine signatures in circulating cell-free DNA as diagnostic biomarkers for human cancers

DNA modifications such as 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) are epigenetic marks known to affect global gene expression in mammals. Given their prevalence in the human genome, close correlation with gene expression and high chemical stability, these DNA epigenetic marks could serve as ideal biomarkers for cancer diagnosis. Taking advantage of a highly sensitive and selective chemical labeling technology, we report here the genome-wide profiling of 5hmC in circulating cell-free DNA (cfDNA) and in genomic DNA (gDNA) of paired tumor and adjacent tissues collected from a cohort of 260 patients recently diagnosed with colorectal, gastric, pancreatic, liver or thyroid cancer and normal tissues from 90 healthy individuals. 5hmC was mainly distributed in transcriptionally active regions coincident with open chromatin and permissive histone modifications. Robust cancer-associated 5hmC signatures were identified in cfDNA that were characteristic for specific cancer types. 5hmC-based biomarkers of circulating cfDNA were highly predictive of colorectal and gastric cancers and were superior to conventional biomarkers and comparable to 5hmC biomarkers from tissue biopsies. Thus, this new strategy could lead to the development of effective, minimally invasive methods for diagnosis and prognosis of cancer from the analyses of blood samples.

Engineered cells for costimulatory enhancement combined with IL-21 enhance the generation of PD-1-disrupted CTLs for adoptive immunotherapy

Blockade of the immune cell checkpoint inhibitors programmed death 1 (PD-1) and programmed death-ligand 1 (PD-L1) has become a powerful tool in cancer treatment, which is effective across various solid cancer types and hematologic malignancies. Our previous studies showed that by reducing immune tolerance, clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR-Cas9) modified cytotoxic T lymphocytes (CTLs) rank highly in terms of immune responses and cytotoxicity. In this study, a genetically modified K562 cell line with surface expression of 4-1BBL was developed to expand PD-1-disrupted CTLs in vitro for further adoptive immunotherapy against cancer. Our findings demonstrate that after a long-term, up to 28days, engineered cells for costimulatory enhancement (ECCE) combined with IL-21 promote the expansion of PD-1-disrupted CTLs with a less differentiated "young" phenotype, enhanced immune response and superior cytotoxic effector characteristics. These new in vitro conditions represent a nimble and cost-effective approach to developing PD-1-disrupted CTLs with improved therapeutic potential.

Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

The Daya Bay experiment has observed correlations between reactor core fuel evolution and changes in the reactor antineutrino flux and energy spectrum. Four antineutrino detectors in two experimental halls were used to identify 2.2 million inverse beta decays (IBDs) over 1230 days spanning multiple fuel cycles for each of six 2.9 GW_{th} reactor cores at the Daya Bay and Ling Ao nuclear power plants. Using detector data spanning effective ^{239}Pu fission fractions F_{239} from 0.25 to 0.35, Daya Bay measures an average IBD yield σ[over ¯]_{f} of (5.90±0.13)×10^{-43}  cm^{2}/fission and a fuel-dependent variation in the IBD yield, dσ_{f}/dF_{239}, of (-1.86±0.18)×10^{-43}  cm^{2}/fission. This observation rejects the hypothesis of a constant antineutrino flux as a function of the ^{239}Pu fission fraction at 10 standard deviations. The variation in IBD yield is found to be energy dependent, rejecting the hypothesis of a constant antineutrino energy spectrum at 5.1 standard deviations. While measurements of the evolution in the IBD spectrum show general agreement with predictions from recent reactor models, the measured evolution in total IBD yield disagrees with recent predictions at 3.1σ. This discrepancy indicates that an overall deficit in the measured flux with respect to predictions does not result from equal fractional deficits from the primary fission isotopes ^{235}U, ^{239}Pu, ^{238}U, and ^{241}Pu. Based on measured IBD yield variations, yields of (6.17±0.17) and (4.27±0.26)×10^{-43}  cm^{2}/fission have been determined for the two dominant fission parent isotopes ^{235}U and ^{239}Pu. A 7.8% discrepancy between the observed and predicted ^{235}U yields suggests that this isotope may be the primary contributor to the reactor antineutrino anomaly.

Controllable picoliter pipetting using hydrophobic microfluidic valves

A picoliter pipetting technique using the microfluidic method is presented. Utilizing the hydrophobic self-assembled monolayer films patterned in microchannels as pressure-controlled valves, a small volume of liquid can be separated by a designed channel trap and then ejected from the channel end at a higher pressure. The liquid trap section is composed of a T-shaped channel junction and a hydrophobic patch. The liquid volume can be precisely controlled by varying the distance of the hydrophobic patch from the T-junction. By this means, liquid less than 100 pl can be separated and pipetted. The developed device is potentially useful for sample dispensing in biological, medical, and chemical applications.

Astaxanthin increases radiosensitivity in esophageal squamous cell carcinoma through inducing apoptosis and G2/M arrest

Nowadays esophageal squamous cell carcinoma (ESCC) is primarily treated by a comprehensive approach combining surgical resection and neoadjuvant chemo- or radiotherapy. However, ESCC is resistant to radiation therapy, resulting in its invasion, infiltration, and metastasis. It usually has rapidly progressed and has a poor outcome clinically. The purpose of this study is to determine the potential radiosensitizing effect of astaxanthin (ATX) and explore the underlying mechanisms in ESCC cells in vitro. ESCC cell lines were exposure to irradiation, in the presence or absence of ATX treatment. Cell viability and radiosensitization were tested by CCK8 assay and clonogenic survival assay, respectively. Cell apoptosis and the changes of cell cycle distribution were observed by flow cytometry. The protein expression of Bcl2, Bax, CyclinB1, and Cdc2 was examined by western blot analysis. It was shown that ATX improved radiosensitivity of ESCC cells and induced apoptosis and G2/M arrest via inhibiting Bcl2, CyclinB1, Cdc2, and promoting Bax expression. In conclusion, ATX might function as a promising radiosensitizer in ESCC cells by leading to apoptosis and G2/M arrest.

Ginsenoside Rg3 to regulate the EMT induced by TGF-in gastric cancer

e23200

Background: To discuss the regulate effect of Ginsenoside Rg3 during the TGF-β1 induced EMT in human gastric cancer SNU-601 cell line. Methods: In the first part of our experiment, ninety-nine patients who were diagnosed as gastric cancer were admitted to this study eventually. The Luminex® xMAP technology was used to measure the plasma levels of TGF-β1. In the second part, human gastric cancer SNU-601 cell line were cultured normally. Inverted microscope was used to observe morphological changes. The cell relative growth rate of proliferation was analyzed by MTT assay. Wound-healing assay and transwell invasion assay were carried out to predict the capacity of Ginsenoside Rg3 in inhibiting migration and invasion. Western Blot was performed to analyze the influence of Ginsenoside Rg3 and TGF-β1 on the protein expression of E-cadherin and Vimentin. Results: The plasma cytokine levels of TGF-β1 were associated with vessel invasion, peritoneal involvement, TNM stage, T stage, N stage in gastric cancer patients. In Vitro Study, TGF-β1 stimulated epithelial-mesenchymal transition in SNU-601 cell lines. Ginsenoside Rg3 inhibited the TGF-β1 induced morphological changes, cell proliferation increase, cell migration and cell invasion. Ginsenoside Rg3 markedly increased expression of the epithelial marker E-cadherin, and repressed the upregulation and expression of the mesenchymal marker Vimentin during the TGF-β1 induced EMT in SNU-601 cell line. Conclusions: The plasma cytokine levels of TGF-β1 were associated with vessel invasion, peritoneal involvement, tumor stage in gastric cancer patients. TGF-β1 stimulated biological malignant behavior through EMT in gastric cancer. Ginsenoside Rg3 could inhibit the EMT induced by TGF-β1 in SNU-601 cell lines.

Phase III study of individualized intraperitoneal/intravenous/oral chemotherapy compared with standard intravenous/oral chemotherapy in patients with advanced gastric cancer

4021

Background: Tumor mRNA expression levels may have a promising role as potential predictive biomarkers for chemotherapy. Intraperitoneal (IP) chemotherapy provides sustained high local concentrations, and its efficacy has been shown in ovarian cancer and gastric cancer patients with peritoneal metastasis. We developed a regimen combining IP/intravenous(IV)/oral chemotherapy for the treatment of advanced gastric cancer patients with individualized chemotherapeutics according to mRNA expression. This multicenter phase III study evaluated the efficacy of individualized multi-route chemotherapy compared to standard systemic chemotherapy. Methods: Eligibility criteria included pathologically confirmed advanced gastric adenocarcinoma, and no prior chemotherapy. Patients were randomized 3:1 to an individualized arm (IN) and standard arm (ST). Randomization was stratified by center. Patients in individualized arm first underwent mRNA expression (BRCA1/TOPO1/TS) to choose sensltive chemotherapeutics from oxaliplatin/cisplatin/docetaxel/irinotecan/S-1 and then received individualized IP/IV/oral chemotherapy. The primary endpoint was overall survival (OS). Secondary endpoints were response rate, progression-free survival (PFS), and safety. Results: Between April 2013 and December 2015, 231 patients were enrolled, and 218 patients were included in the efficacy analysis. Baseline patient characteristics were balanced between the two arms. The median OS for IN and ST were 16.3 and 14.1 months, respectively (adjusted hazard ratio [aHR] 0.77, 95% confidence interval [CI] 0.61-0.98, p < 0.05). The overall response rate was 44.0% in the IN arm, and 33.9% in the ST arm (p < 0.05). Both regimens were tolerable. Conclusions: The primary analysis showed the statistical superiority of the individualized multi-route regimen. It suggested clinical efficacy of this regimen in patients with advanced gastric cancer. Clinical trial information: ChiCTR-IPR-15006201.

Incidence and Risk Factors for Cytomegalovirus Infection in Patients With Kidney Transplantation: A Single-Center Experience

BACKGROUND

Cytomegalovirus (CMV) infection is deemed to be a major cause of morbidity and mortality in patients after kidney transplantation. The purpose of this study was to analyze the incidence of CMV infection and risk factors for CMV infection in our center, to help in determination of its impact on the kidney function in this patient population, and to provide new ideas for the prevention and treatment of CMV infection.

METHODS

A total of 319 kidney transplant recipients from our center were studied between January 2000 and December 2015. The CMV viral load in each kidney transplant patients was monitored with the use of CMV quantitative nucleic acid testing (CMV-QNAT). Laboratory data and other medical records were also collected.

RESULTS

The incidence of CMV infection was 8.8% in our studied patients. The patients within 3 to 6 months and 5 to 10 years after transplantation had a higher risk of CMV infection. CMV infection was probably correlated with lower white blood cell counts but elevated hemoglobin, serum creatinine, blood urea nitrogen, potassium, and estimated glomerular filtration rate (eGFR). Anti-CMV immunoglobulin (Ig)G and history of allograft rejection were also associated with CMV infection. In multivariate regression analysis, white blood cells, eGFR, anti-CMV IgG, and history of allograft rejection were the independent risk factors associated with CMV infection in kidney transplantation patients.

CONCLUSIONS

CMV infection was an important complication after kidney transplantation, particularly in these patients with allograft impairment.

Human cytotoxic T-lymphocyte membrane-camouflaged nanoparticles combined with low-dose irradiation: a new approach to enhance drug targeting in gastric cancer

Cell membrane-derived nanoparticles are becoming more attractive because of their ability to mimic many features of their source cells. This study reports on a biomimetic delivery platform based on human cytotoxic T-lymphocyte membranes. In this system, the surface of poly-lactic-co-glycolic acid nanoparticles was camouflaged using T-lymphocyte membranes, and local low-dose irradiation (LDI) was used as a chemoattractant for nanoparticle targeting. The T-lymphocyte membrane coating was verified using dynamic light scattering, transmission electron microscopy, and confocal laser scanning microscopy. This new platform reduced nanoparticle phagocytosis by macrophages to 23.99% (P=0.002). Systemic administration of paclitaxel-loaded T-lymphocyte membrane-coated nanoparticles inhibited the growth of human gastric cancer by 56.68% in Balb/c nude mice. Application of LDI at the tumor site significantly increased the tumor growth inhibition rate to 88.50%, and two mice achieved complete remission. Furthermore, LDI could upregulate the expression of adhesion molecules in tumor vessels, which is important in the process of leukocyte adhesion and might contribute to the localization of T-lymphocyte membrane-encapsulated nanoparticles in tumors. Therefore, this new drug-delivery platform retained both the long circulation time and tumor site accumulation ability of human cytotoxic T lymphocytes, while local LDI could significantly enhance tumor localization.

Gambogic acid-loaded biomimetic nanoparticles in colorectal cancer treatment

Gambogic acid (GA) is expected to be a potential new antitumor drug, but its poor aqueous solubility and inevitable side effects limit its clinical application. Despite these inhe rent defects, various nanocarriers can be used to promote the solubility and tumor targeting of GA, improving antitumor efficiency. In addition, a cell membrane-coated nanoparticle platform that was reported recently, unites the customizability and flexibility of a synthetic copolymer, as well as the functionality and complexity of natural membrane, and is a new synthetic biomimetic nanocarrier with improved stability and biocompatibility. Here, we combined poly(lactic-co-glycolic acid) (PLGA) with red blood-cell membrane (RBCm), and evaluated whether GA-loaded RBCm nanoparticles can retain and improve the antitumor efficacy of GA with relatively lower toxicity in colorectal cancer treatment compared with free GA. We also confirmed the stability, biocompatibility, passive targeting, and few side effects of RBCm-GA/PLGA nanoparticles. We expect to provide a new drug carrier in the treatment of colorectal cancer, which has strong clinical application prospects. In addition, the potential antitumor drug GA and other similar drugs could achieve broader clinical applications via this biomimetic nanocarrier.

Supramolecular Amphiphilic Polymer-Based Micelles with Seven-Armed Polyoxazoline Coating for Drug Delivery

Supramolecular polymer micelles composed of seven-armed poly(2-methy-2-oxazoline) as the coating and linear poly(dl-lactide) as the core were prepared through synthesizing β-cyclodextrin-terminated poly(2-methy-2-oxazoline) and adamantine-terminated linear poly(dl-lactide), followed by host-guest interaction between β-cyclodextrin and adamantine groups in two polymers and self-assembly in aqueous solution. Dynamic light-scattering measurement showed that the micelles based on supramolecular amphiphilic polymers have the size of 119 nm and were highly stable in salt solution. When the micelles were used as the carrier of cabazitaxel, an antitumor agent for drug-resistant cancers, satisfactory drug loading content and encapsulation efficacy were obtained. In vitro cellular cytotoxicity assays found that cabazitaxel-loaded micelles presented obvious cytotoxicity against taxane-sensitive and -resistant cancer cells. Further in vivo antitumor activity evaluation showed that cabazitaxel-loaded micelles have significantly superior efficacy in inhibiting tumor growth and prolonging survival in tumor-bearing mice compared to that of free paclitaxel and free cabazitaxel.