Long-term outcomes of intraoperative chemotherapy with 5-FU for colorectal cancer patients receiving curative resection (IOCCRC): a randomized, multicenter, prospective, phase III trial.

BACKGROUND: We aimed to compare combined intraoperative chemotherapy and surgical resection with curative surgical resection alone in colorectal cancer patients. METHODS: We performed a multicenter, open-label, randomized, phase III trial. All eligible patients were randomized and assigned to intraoperative chemotherapy and curative surgical resection or curative surgical resection alone (1:1). Survival actualization after long-term follow-up was performed in patients analyzed on an intention-to-treat basis. RESULTS: From January 2011 to January 2016, 696 colorectal cancer patients were enrolled and randomly assigned to intraoperative chemotherapy and radical surgical resection (n=341) or curative surgical resection alone (n=344). Intraoperative chemotherapy with surgical resection showed no significant survival benefit over surgical resection alone in colorectal cancer patients (3-year DFS: 91.1% vs. 90.0%, P=0.328; 3-year OS: 94.4% vs. 95.9%, P=0.756). However, colon cancer patients benefitted from intraoperative chemotherapy, with a relative 4% reduction in liver and peritoneal metastasis (HR=0.336, 95% CI: 0.148-0.759, P=0.015) and a 6.5% improvement in 3-year DFS (HR=0.579, 95% CI: 0.353-0.949, P=0.032). Meanwhile, patients with colon cancer and abnormal pretreatment CEA levels achieved significant survival benefits from intraoperative chemotherapy (DFS: HR=0.464, 95% CI: 0.233-0.921, P=0.029 and OS: (HR=0.476, 95% CI: 0.223-1.017, P=0.049). CONCLUSIONS: Intraoperative chemotherapy showed no significant extra prognostic benefit in total colorectal cancer patients who underwent radical surgical resection; however, in colon cancer patients with abnormal pretreatment serum CEA levels (> 5 ng/ml), intraoperative chemotherapy could improve long-term survival.

Chemoenzymatic Installation of Site-Specific Chemical Groups on DNA Enhances the Catalytic Activity.

Functional DNAs are valuable molecular tools in chemical biology and analytical chemistry but suffer from low activities due to their limited chemical functionalities. Here, we present a chemoenzymatic method for site-specific installation of diverse functional groups on DNA, and showcase the application of this method to enhance the catalytic activity of a DNA catalyst. Through chemoenzymatic introduction of distinct chemical groups, such as hydroxyl, carboxyl, and benzyl, at specific positions, we achieve significant enhancements in the catalytic activity of the RNA-cleaving deoxyribozyme 10-23. A single carboxyl modification results in a 100-fold increase, while dual modifications (carboxyl and benzyl) yield an approximately 700-fold increase in activity when an RNA cleavage reaction is catalyzed on a DNA-RNA chimeric substrate. The resulting dually modified DNA catalyst, CaBn, exhibits a kobs of 3.76 min-1 in the presence of 1 mM Mg2+ and can be employed for fluorescent imaging of intracellular magnesium ions. Molecular dynamics simulations reveal the superior capability of CaBn to recruit magnesium ions to metal-ion-binding site 2 and adopt a catalytically competent conformation. Our work provides a broadly accessible strategy for DNA functionalization with diverse chemical modifications, and CaBn offers a highly active DNA catalyst with immense potential in chemistry and biotechnology.

The role of ATG5 beyond Atg8ylation and autophagy.

ATG5 plays a pivotal role in membrane Atg8ylation, influencing downstream processes encompassing canonical autophagy and noncanonical processes. Remarkably, genetic ablation of ATG5 in myeloid cells leads to an exacerbated pathological state in murine models of tuberculosis, characterized by an early surge in mortality much more severe when compared to the depletion of other components involved in Atg8ylation or canonical autophagy. This study shows that in the absence of ATG5, but not other core canonical autophagy factors, endolysosomal organelles display a lysosomal hypersensitivity phenotype when subjected to damage. This is in part due to a compromised recruitment of ESCRT proteins to lysosomes in need of repair. Mechanistically, in the absence of ATG5, the ESCRT protein PDCD6IP/ALIX is sequestered by the alternative conjugate ATG12-ATG3, contributing to excessive exocytic processes while not being available for lysosomal repair. Specifically, this condition increases secretion of extracellular vesicles and particles, and leads to excessive degranulation in neutrophils. Our findings uncover unique functions of ATG5 outside of the autophagy and Atg8ylation paradigm. This finding is of in vivo relevance for tuberculosis pathogenesis as modeled in mice.Abbreviations: Atg5: autophagy related 5; ESCRT: endosomal sorting complex required for transport; EVPs: extracellular vesicles and particles; FPR1: formyl peptide receptor 1; LyHYP: lysosomal hypersensitivity phenotype; LysoIP: lysosome immunopurification; Mtb: Mycobacterium tuberculosis; ORF3a: open reading frame 3a protein; PDCD6IP/ALIX: programmed cell death 6 interacting protein; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2, TFEB: transcription factor EB.

Laser Controlled Manipulation of Microbubbles on a Surface with Silica-Coated Gold Nanoparticle Array.

Microbubble generation and manipulation play critical roles in diverse applications such as microfluidic mixing, pumping, and microrobot propulsion. However, existing methods are typically limited to lateral movements on customized substrates or rely on specific liquids with particular properties or designed concentration gradients, thereby hindering their practical applications. To address this challenge, this paper presents a method that enables robust vertical manipulation of microbubbles. By focusing a resonant laser on hydrophilic silica-coated gold nanoparticle arrays immersed in water, plasmonic microbubbles are generated and detach from the substrates immediately upon cessation of laser irradiation. Using simple laser pulse control, it can achieve an adjustable size and frequency of bubble bouncing, which is governed by the movement of the three-phase contact line during surface wetting. Furthermore, it demonstrates that rising bubbles can be pulled back by laser irradiation induced thermal Marangoni flow, which is verified by particle image velocimetry measurements and numerical simulations. This study provides novel insights into flexible bubble manipulation and integration in microfluidics, with significant implications for various applications including mixing, drug delivery, and the development of soft actuators.

Mammalian ATG8 proteins maintain autophagosomal membrane integrity through ESCRTs.

The canonical autophagy pathway in mammalian cells sequesters diverse cytoplasmic cargo within the double membrane autophagosomes that eventually convert into degradative compartments via fusion with endolysosomal intermediates. Here, we report that autophagosomal membranes show permeability in cells lacking principal ATG8 proteins (mATG8s) and are unable to mature into autolysosomes. Using a combination of methods including a novel in vitro assay to measure membrane sealing, we uncovered a previously unappreciated function of mATG8s to maintain autophagosomal membranes in a sealed state. The mATG8 proteins GABARAP and LC3A bind to key ESCRT-I components contributing, along with other ESCRTs, to the integrity and imperviousness of autophagic membranes. Autophagic organelles in cells lacking mATG8s are permeant, are arrested as amphisomes, and do not progress to functional autolysosomes. Thus, autophagosomal organelles need to be maintained in a sealed state in order to become lytic autolysosomes.

Dissected subgroups predict the risk of recurrence of stage II colorectal cancer and select rational treatment.

Background: Stage II colorectal cancer(CRC) patients after surgery alone have a five-year survival rate of ~60-80%; the incremental benefit of adjuvant chemotherapy is <5%. Predicting risk of recurrence and selecting effective personalized adjuvant drugs for stage II CRC using formalin-fixed, paraffin-embedded(FFPE) samples is a major challenge. Methods: 1319 stage II CRC patients who enrolled in 2011-2019 at Sun Yat-sen University Cancer Center were screened. RNAseq data of FFPE tumor samples of 222 stage II microsatellite stable(MSS) CRC patients(recurrence (n=47), norecurrence (n=175), median follow-up=41 months) were used to develop a method TFunctionalProg for dissecting heterogeneous subgroups of recurrence and predicting risk of recurrence. Results: TFunctionalProg showed significant predictive values in 222 stage II MSS CRCs. The TFunctionalProg low-risk group had significantly better recurrence free survival (validation set: HR=4.78, p-value=1e-4, low-risk group three-year recurrence free survival=92.6%, high-risk group three-year recurrence free survival=59.7%). TFunctionalProg dissected two subgroups of transition states of stage II MSS CRCs at a high risk of recurrence; each state displays distinct levels of hybrid epithelial-mesenchymal traits, CD8+ T cell suppression mechanisms and FOLFOX resistance. Based on mechanisms in two subgroups, TFunctionalProg proposed personalized rational adjuvant drug combinations of immunotherapy, chemotherapy and repurposed CNS drugs. TFunctionalProg provides different utilities from ctDNA-based prognostic biomarkers. Conclusion: TFunctionalProg was validated using FFPE samples to predict the risk of recurrence and propose rational adjuvant drug combinations for stage II CRC.

ATG5 provides host protection acting as a switch in the atg8ylation cascade between autophagy and secretion.

ATG5 is a part of the E3 ligase directing lipidation of ATG8 proteins, a process central to membrane atg8ylation and canonical autophagy. Loss of Atg5 in myeloid cells causes early mortality in murine models of tuberculosis. This in vivo phenotype is specific to ATG5. Here, we show using human cell lines that absence of ATG5, but not of other ATGs directing canonical autophagy, promotes lysosomal exocytosis and secretion of extracellular vesicles and, in murine Atg5fl/fl LysM-Cre neutrophils, their excessive degranulation. This is due to lysosomal disrepair in ATG5 knockout cells and the sequestration by an alternative conjugation complex, ATG12-ATG3, of ESCRT protein ALIX, which acts in membrane repair and exosome secretion. These findings reveal a previously undescribed function of ATG5 in its host-protective role in murine experimental models of tuberculosis and emphasize the significance of the branching aspects of the atg8ylation conjugation cascade beyond the canonical autophagy.

Neoadjuvant PD-1 blockade with sintilimab in mismatch-repair deficient, locally advanced rectal cancer: an open-label, single-centre phase 2 study.

BACKGROUND: The current standard treatment for locally advanced rectal cancer is neoadjuvant chemoradiotherapy followed by radical surgery, but this approach can lead to multiple complications. We aimed to investigate the clinical activity and safety of neoadjuvant therapy with sintilimab, a single-agent PD-1 antibody, in patients with mismatch-repair deficient locally advanced rectal cancer. METHODS: This open-label, single-arm, phase 2 study was done at the Sun Yat-sen University Cancer Center, Guangzhou, China. Patients aged 18-75 years with mismatch-repair deficient or microsatellite instability-high locally advanced rectal cancer were enrolled and received neoadjuvant sintilimab monotherapy (200 mg by intravenous infusion) every 21 days. After an initial four cycles of treatment, patients and clinicians could choose one of the following options: total mesorectal excision surgery, followed by four cycles of adjuvant sintilimab with or without CapeOX chemotherapy (capecitabine 1000 mg/m2, orally administered twice daily on days 1-14; oxaliplatin 130 mg/m2, intravenously administered on day 1 every 3 weeks), determined by clinicians; or another four cycles of sintilimab followed by radical surgery or observation (only for patients with a clinical complete response; also known as the watch and wait strategy). The primary endpoint was the complete response rate, which included both a pathological complete response after surgery and a clinical complete response after completion of sintilimab treatment. Clinical response was evaluated by digital rectal examination, MRI, and endoscopy. Response was assessed in all patients who received treatment at least until the first tumour response assessment, after the first two cycles of sintilimab. Safety was analysed in all patients who received at least one dose of treatment. This trial is closed to enrolment and is registered with ClinicalTrials.gov (NCT04304209). FINDINGS: Between Oct 19, 2019, and June 18, 2022, 17 patients were enrolled and received at least one dose of sintilimab. The median age was 50 years (IQR 35-59) and 11 (65%) of 17 patients were male. One patient was excluded from efficacy analyses because they were lost to follow-up after the first sintilimab cycle. Of the remaining 16 patients, six underwent surgery, of whom three had a pathological complete response. Nine other patients had a clinical complete response and chose the watch and wait strategy. One patient had a serious adverse event and discontinued treatment; this patient did not have a complete clinical response and refused to undergo surgery. A complete response was thus noted for 12 (75%; 95% CI 47-92) of 16 patients. One of the three patients who underwent surgery but did not have a pathological complete response showed an increase in tumour volume after the initial four cycles of sintilimab (at which point they underwent surgery); this patient was deemed to have primary resistance to immune checkpoint inhibitors. After a median follow-up of 17·2 (IQR 8·2-28·5) months, all patients were alive and none had disease recurrence. Only one (6%) patient had a grade 3-4 adverse event, which was deemed a serious adverse event (grade 3 encephalitis). INTERPRETATION: The preliminary results of this study suggest that anti-PD-1 monotherapy is effective and tolerable for patients with mismatch-repair deficient locally advanced rectal cancer and could potentially spare some patients from radical surgery. Longer treatment courses might be needed to achieve maximum effects in some patients. Longer follow-up is also needed to observe the duration of response. FUNDING: The National Natural Science Foundation of China, CAMS Innovation Fund for Medical Sciences, Science and Technology Program of Guangzhou, and Innovent Biologics.

Prognostic and predictive value of Immunoscore and its correlation with ctDNA in stage II colorectal cancer.

This study aimed to validate the prognostic value of Immunoscore (IS) in stage II colorectal cancer (CRC), and explore the roles of IS and circulating tumor DNA (ctDNA) in the adjuvant treatment for early-stage CRC. Resected tumor samples from stage II CRC patients were collected from the Sun Yat-sen University Cancer Center. The densities of CD3+ and CD8+ lymphocytes were quantified and converted to IS and classified into Low, Intermediate (Int), and High groups according to predefined cutoffs. A total of 113 patients were included in the study. Patients with IS-High, Int, and Low were 43 (38%), 62 (55%), and 8 (7%), respectively. Patients with IS-High had an excellent clinical outcome, with none recurring during a median follow-up of 3 years, including 15 (35%) clinical high-risk patients. The 3-year disease-free survival (DFS) was 100% for IS-High, 76% for IS-Int, and 47% for IS-Low (P < .001). In the multivariate Cox analysis, IS was the only significant parameter associated with DFS. IS-Int and IS-Low patients with adjuvant chemotherapy had improved DFS compared to those who did not receive adjuvant chemotherapy (HR = 0.3; 95% CI 0.1-0.92; P = .026). Among the 49 patients with postoperative ctDNA data, IS-High patients had the lowest ctDNA positivity rate, suggesting that they were most eligible for chemotherapy-free treatment. IS had a strong prognostic value in Chinese patients with stage II CRC and demonstrates its clinical utility. IS and ctDNA will jointly optimize the adjuvant treatment strategies for early-stage CRC.

Membrane Atg8ylation, stress granule formation, and MTOR regulation during lysosomal damage.

The functions of mammalian Atg8 proteins (mATG8s) expand beyond canonical autophagy and include processes collectively referred to as Atg8ylation. Global modulation of protein synthesis under stress conditions is governed by MTOR and liquid-liquid phase separated condensates containing ribonucleoprotein particles known as stress granules (SGs). We report that lysosomal damage induces SGs acting as a hitherto unappreciated inhibitor of protein translation via EIF2A/eIF2α phosphorylation while favoring an ATF4-dependent integrated stress response. SGs are induced by lysosome-damaging agents, SARS-CoV-2 open reading frame 3a protein (ORF3a) expression, Mycobacterium tuberculosis infection, and exposure to proteopathic MAPT/tau. Proteomic studies revealed recruitment to damaged lysosomes of the core SG proteins NUFIP2 and G3BP1 along with the GABARAPs of the mATG8 family. The recruitment of these proteins is independent of SG condensates or canonical autophagy. GABARAPs interact directly with NUFIP2 and G3BP1 whereas Atg8ylation is needed for their recruitment to damaged lysosomes. At the lysosome, NUFIP2 contributes to MTOR inactivation together with LGALS8 (galectin 8) via the Ragulator-RRAGA-RRAGB complex. The separable functions of NUFIP2 and G3BP1 in SG formation vis-a-vis their role in MTOR inactivation are governed by GABARAP and Atg8ylation. Thus, cells employ membrane Atg8ylation to control and coordinate SG and MTOR responses to lysosomal damage.Abbreviations: Atg8: autophagy related 8; ATG: autophagy related; ATF4: activating transcription factor 4; EIF2A/eIF2α: eukaryotic translation initiation factor 2A; GABARAP: GABA type A receptor-associated protein; G3BP1: G3BP stress granule assembly factor 1; LLOMe: L-leucyl-L-leucine methyl ester; LysoIP: lysosome immunopurification; mRNA: messenger ribonucleic acid; MTOR: mechanistic target of rapamycin kinase; NUFIP2: nuclear FMR1 interacting protein 2; ORF3a: open reading frame 3a protein; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; SG: stress granule; TIA1: TIA1 cytotoxic granule associated RNA binding protein.

Case report: Reproductive organ preservation and subsequent pregnancy for an infertility patient with lynch syndrome-associated synchronous endometrial cancer and colon cancer after treatment with a PD-1 checkpoint inhibitor.

Currently, immune checkpoint inhibitors (ICIs) are the mainstay of treatment for Lynch syndrome patients. However, the tumor regression features in radiology and pathology are inconsistent for patients who are treated with ICIs, which sometimes confuses surgical decision-making. Here, we report a case in which a 36-year-old patient suffering from infertility was diagnosed with Lynch syndrome-associated synchronous endometrial cancer and colon cancer, and persistently enlarged left iliac paravascular lymph nodes were detected after receiving sintilimab treatment, a programmed cell death 1 (PD-1) receptor inhibitor. Fortunately, when she was about to undergo hysterectomy and bilateral salpingo-oophorectomy, intraoperative pathology examination did not reveal any cancer cells in these lymph nodes, and therefore, her reproductive organs were preserved. Later, the patient successfully conceived and gave birth to a healthy male neonate with no immune-related adverse events (irAEs) during an 11-month follow-up. This case indicates that surgeons should carefully inspect the imaging characteristics after immunotherapy and that organ preservation is possible even for patients who fail to achieve complete clinical regression, which is especially important for female patients of childbearing age.

Stress granules and mTOR are regulated by membrane atg8ylation during lysosomal damage.

We report that lysosomal damage is a hitherto unknown inducer of stress granule (SG) formation and that the process termed membrane atg8ylation coordinates SG formation with mTOR inactivation during lysosomal stress. SGs were induced by lysosome-damaging agents including SARS-CoV-2ORF3a, Mycobacterium tuberculosis, and proteopathic tau. During damage, mammalian ATG8s directly interacted with the core SG proteins NUFIP2 and G3BP1. Atg8ylation was needed for their recruitment to damaged lysosomes independently of SG condensates whereupon NUFIP2 contributed to mTOR inactivation via the Ragulator-RagA/B complex. Thus, cells employ membrane atg8ylation to control and coordinate SG and mTOR responses to lysosomal damage.

Clutter Suppression Method for Off-Grid Effects Mitigation in Airborne Passive Radars with Contaminated Reference Signals.

For an airborne passive radar with contaminated reference signals, the clutter caused by multipath (MP) signals involved in the reference channel (MP clutter) corrupts the covariance estimation in space-time adaptive processing (STAP). In order to overcome the severe STAP performance degradation caused by impure reference signals and off-grid effects, a novel MP clutter suppression method based on local search is proposed for airborne passive radar. In the proposed method, the global dictionary is constructed based on the sparse measurement model of MP clutter, and the global atoms that are most relevant to the residual are selected. Then, the local dictionary is designed iteratively, and local searches are performed to match real MP clutter points. Finally, the off-grid effects are mitigated, and the MP clutter is suppressed from all matched atoms. A range of simulations is conducted in order to demonstrate the effectiveness of the proposed method.

Global Pattern of CD8+ T-Cell Infiltration and Exhaustion in Colorectal Cancer Predicts Cancer Immunotherapy Response.

Background: The MSI/MSS status does not fully explain cancer immunotherapy response in colorectal cancer. Thus, we developed a colorectal cancer-specific method that predicts cancer immunotherapy response. Methods: We used gene expression data of 454 samples (MSI = 131, MSI-L = 23, MSS = 284, and Unknown = 16) and developed a TMEPRE method that models signatures of CD8+ T-cell infiltration and CD8+ T-cell exhaustion states in the tumor microenvironment of colorectal cancer. TMEPRE model was validated on three RNAseq datasets of melanoma patients who received pembrolizumab or nivolumab and one RNAseq dataset of purified CD8+ T cells in different exhaustion states. Results: TMEPRE showed predictive power in three datasets of anti-PD1-treated patients (p = 0.056, 0.115, 0.003). CD8+ T-cell exhaustion component of TMEPRE model correlates with anti-PD1 responding progenitor exhausted CD8+ T cells in both tumor and viral infection (p = 0.048, 0.001). The global pattern of TMEPRE on 454 colorectal cancer samples indicated that 10.6% of MSS patients and 67.2% of MSI patients show biological characteristics that can potentially benefit from anti-PD1 treatment. Within MSI nonresponders, approximately 50% showed insufficient tumor-infiltrating CD8+ T cells and 50% showed terminal exhaustion of CD8+ T cells. These terminally exhausted CD8+ T cells coexisted with signatures of myeloid-derived suppressor cells in colorectal cancer. Conclusion: TMEPRE is a colorectal cancer-specific method. It captures characteristics of CD8+ T-cell infiltration and CD8+ T-cell exhaustion state and predicts cancer immunotherapy response. A subset of MSS patients could potentially benefit from anti-PD1 treatment. Anti-PD1 resistance MSI patients with insufficient infiltration of CD8+ T cells or terminal exhaustion of CD8+ T cells need different treatment strategies.

ATG9A protects the plasma membrane from programmed and incidental permeabilization.

The integral membrane protein ATG9A plays a key role in autophagy. It displays a broad intracellular distribution and is present in numerous compartments, including the plasma membrane (PM). The reasons for the distribution of ATG9A to the PM and its role at the PM are not understood. Here, we show that ATG9A organizes, in concert with IQGAP1, components of the ESCRT system and uncover cooperation between ATG9A, IQGAP1 and ESCRTs in protection from PM damage. ESCRTs and ATG9A phenocopied each other in protection against PM injury. ATG9A knockouts sensitized the PM to permeabilization by a broad spectrum of microbial and endogenous agents, including gasdermin, MLKL and the MLKL-like action of coronavirus ORF3a. Thus, ATG9A engages IQGAP1 and the ESCRT system to maintain PM integrity.

Postoperative circulating tumor DNA as markers of recurrence risk in stages II to III colorectal cancer.

BACKGROUND: Precise methods for postoperative risk stratification to guide the administration of adjuvant chemotherapy (ACT) in localized colorectal cancer (CRC) are still lacking. Here, we conducted a prospective, observational, and multicenter study to investigate the utility of circulating tumor DNA (ctDNA) in predicting the recurrence risk. METHODS: From September 2017 to March 2020, 276 patients with stage II/III CRC were prospectively recruited in this study and 240 evaluable patients were retained for analysis, of which 1290 serial plasma samples were collected. Somatic variants in both the primary tumor and plasma were detected via a targeted sequencing panel of 425 cancer-related genes. Patients were treated and followed up per standard of care. RESULTS: Preoperatively, ctDNA was detectable in 154 of 240 patients (64.2%). At day 3-7 postoperation, ctDNA positivity was associated with remarkably high recurrence risk (hazard ratio [HR], 10.98; 95%CI, 5.31-22.72; P < 0.001). ctDNA clearance and recurrence-free status was achieved in 5 out of 17 ctDNA-positive patients who were subjected to ACT. Likewise, at the first sampling point after ACT, ctDNA-positive patients were 12 times more likely to experience recurrence (HR, 12.76; 95%CI, 5.39-30.19; P < 0.001). During surveillance after definitive therapy, ctDNA positivity was also associated with extremely high recurrence risk (HR, 32.02; 95%CI, 10.79-95.08; P < 0.001). In all multivariate analyses, ctDNA positivity remained the most significant and independent predictor of recurrence-free survival after adjusting for known clinicopathological risk factors. Serial ctDNA analyses identified recurrence with an overall accuracy of 92.0% and could detect disease recurrence ahead of radiological imaging with a mean lead time of 5.01 months. CONCLUSIONS: Postoperative serial ctDNA detection predicted high relapse risk and identified disease recurrence ahead of radiological imaging in patients with stage II/III CRC. ctDNA may be used to guide the decision-making in postsurgical management.

Identification of Two Subgroups of FOLFOX Resistance Patterns and Prediction of FOLFOX Response in Colorectal Cancer Patients.

To dissect gene expression subgroups of FOLFOX resistance colorectal cancer(CRC) and predict FOLFOX response, gene expression data of 83 stage IV CRC tumor samples (FOLFOX responder n = 42, non-responder n = 41) are used to develop a novel iterative supervised learning method IML. IML identified two mutually exclusive subgroups of CRC patients that rely on different DNA damage repair proteins and resist FOLFOX. IML was validated in two validation sets (HR = 2.6, p Value = 0.02; HR = 2.36, p value = 0.02). A subgroup of mesenchymal subtype patients benefit from FOLFOX. Different subgroups of FOLFOX nonresponders may need to be treated differently.

Characterization of a DNA-hydrolyzing DNAzyme for generation of PCR strands of unequal length.

I-R3 DNAzyme is a small, highly active catalytic DNA for DNA hydrolysis. In here, we designed two cis-structure DNAzymes (I-R3N and I-R3S) based on the different locates of the joint linker between I-R3 and its substrate. Data demonstrated that both DNAzymes were highly dependent on Zn2+, and worked at a narrow range around pH 7.0. They exhibited strong anti-interference with Mg2+ and Ca2+, but inhibited by Na+ and K+. Moreover, single and multiple-site mutations were generated within the catalytic core to carry out a comprehensive mutational study of I-R3 motif, in which most nucleotides were highly conserved and the nucleotides A5, T11 and T8 were identified as the mutational hotspots. Furthermore, an efficient variant A5G was obtained and its reaction condition was optimized. Finally, we constructed A5G to the 3' end of a single-stranded DNA (ssDNA) and applied it for asymmetrical PCR amplification to produce a single and double-stranded DNA mixture, in which A5G within ssDNA can self-cleave to generate a shorter desired ssDNA by denaturing gel separation. This would provide a new non-chemical modification approach for preparation of the expected ssDNA for in vitro selection of DNAzymes.

Core-shell structured PtRu nanoparticles@FeP promoter with an efficient nanointerface for alcohol fuel electrooxidation.

In this study, a bottleneck was overcome for direct alcohol fuel cells using state-of-the-art PtRu catalysts for alcohol fuel oxidation. Herein, a core-shell structured PtRu catalyst system based on the emerging promoter FeP was developed that showed excellent catalytic performance for the oxidation of alcohol fuels. The surface spectrometric analysis and morphology observation confirmed the formation of a nanointerface of the PtRu shell and FeP core hybrid catalyst (PtRu@FeP), and efficient ligand effects and electronic effects were found to result from the noble metal active sites and adjacent promoter in the core-shell structure. The facile formation of oxygen-containing species and the strong electronic effects could activate the Pt active sites, leading to high catalytic performance. High anti-CO poisoning ability was found for this catalyst system when compared with the case of the benchmark commercial PtRu/C catalyst (110 mV less and 60 mV less as evaluated by the peak and onset potentials for CO oxidation, respectively). The PtRu@FeP catalysts also exhibited much higher catalytic activity and stability when compared with commercial and home-made PtRu/C catalysts; specifically, the peak current density of the PtRu@FeP 1 : 1 catalyst was about 2 and 3 times higher than those of the commercial PtRu/C catalyst and home-made PtRu/C for the oxidation of the alcohol fuels methanol and ethanol; moreover, high catalytic efficiency, improved by 2 times, was found, as expressed by the specific activity. Excellent catalytic stability as evaluated by 1000 cycles of cyclic voltammetry measurements was also demonstrated for the PtRu@FeP catalysts. The high catalytic performance could be attributed to the intimate nanointerface contact of the core-shell structured PtRu shell over the FeP core via a bi-functional catalytic mechanism and electronic effects based on the ligand effect in this catalyst system. The current study is a significant step to increase the PtRu catalytic performance via nanointerface construction by a core-shell structure on a novel promoter for direct alcohol fuel cells.