The molecular classification of cancer-associated fibroblasts on a pan-cancer single-cell transcriptional atlas.

BACKGROUND: Cancer-associated fibroblasts (CAFs), integral to the tumour microenvironment, are pivotal in cancer progression, exhibiting either pro-tumourigenic or anti-tumourigenic functions. Their inherent phenotypic and functional diversity allows for the subdivision of CAFs into various subpopulations. While several classification systems have been suggested for different cancer types, a unified molecular classification of CAFs on a single-cell pan-cancer scale has yet to be established. METHODS: We employed a comprehensive single-cell transcriptomic atlas encompassing 12 solid tumour types. Our objective was to establish a novel molecular classification and to elucidate the evolutionary trajectories of CAFs. We investigated the functional profiles of each CAF subtype using Single-Cell Regulatory Network Inference and Clustering and single-cell gene set enrichment analysis. The clinical relevance of these subtypes was assessed through survival curve analysis. Concurrently, we employed multiplex immunofluorescence staining on tumour tissues to determine the dynamic changes of CAF subtypes across different tumour stages. Additionally, we identified the small molecule procyanidin C1 (PCC1) as a target for matrix-producing CAF (matCAF) using molecular docking techniques and further validated these findings through in vitro and in vivo experiments. RESULTS: In our investigation of solid tumours, we identified four molecular clusters of CAFs: progenitor CAF (proCAF), inflammatory CAF (iCAF), myofibroblastic CAF (myCAF) and matCAF, each characterised by distinct molecular traits. This classification was consistently applicable across all nine studied solid tumour types. These CAF subtypes displayed unique evolutionary pathways, functional roles and clinical relevance in various solid tumours. Notably, the matCAF subtype was associated with poorer prognoses in several cancer types. The targeting of matCAF using the identified small molecule, PCC1, demonstrated promising antitumour activity. CONCLUSIONS: Collectively, the various subtypes of CAFs, particularly matCAF, are crucial in the initiation and progression of cancer. Focusing therapeutic strategies on targeting matCAF in solid tumours holds significant potential for cancer treatment.

Highly efficient rare-earth free vanadate phosphors for WLEDs.

Yellow-green emitting phosphors of vanadate Ca5Mg4(VO4)6 (CMV) doped with different concentrations of Ta5+ ions were synthesized by a solid-state reaction method. The formation of single-phase compounds with a garnet structure was verified by X-ray diffraction (XRD), Rietveld refinement calculations and energy-dispersive X-ray spectroscopy. Different luminescence properties of CMV phosphors such as spectral shift, luminescence lifetime, quantum efficiency, color coordinates and Stokes shift were measured and have been discussed in detail. PLE and PL spectra showed that CMV : xTa5+ (0 ≤ x ≤ 5%) phosphors could match well to 365 nm LED chips, and showed bright yellow-green emission in the visible range of 400-750 nm, with a peak at 544 nm, which is attributed to the charge transfer (CT) of an electron from the 2p orbital of the oxygen atom to the vacant 3d orbital of V5+ ions in the tetrahedral [VO4]3- group. Compared with the CMV host, the integrated luminescence intensity of CMV : 0.5%Ta5+ increased by 26.31%, and the quantum efficiency increased by 15.98%. The phenomenon can be ascribed to the substitution of V5+ ions by the large Ta5+ ions, which resulted in the squeezed and distorted VO4 tetrahedron. Finally, the white light emitting diode (WLED) devices prepared with UV WLED chips and the CMV : 0.5%Ta5+ phosphor exhibited excellent color temperature (4083 K) and CIE coordinates (0.3677, 0.3409). The CMV : 0.5%Ta5+ phosphor can be considered as a potential yellow-green emitting phosphor in the solid-state lighting field.

MLK4 promotes glucose metabolism in lung adenocarcinoma through CREB-mediated activation of phosphoenolpyruvate carboxykinase and is regulated by KLF5.

MLK4, a member of the mitogen-activated protein kinase kinase kinase (MAP3K) family, has been implicated in cancer progression. However, its role in lung adenocarcinoma has not been characterized. Here, we showed that MLK4 was overexpressed in a significant subset of lung adenocarcinoma, associated with a worse prognosis, and exerted an oncogenic function in vitro and in vivo. Bioinformatics analyses of clinical datasets identified phosphoenolpyruvate carboxykinase 1 (PCK1) as a novel target of MLK4. We validated that MLK4 regulated PCK1 expression at transcriptional level, by phosphorylating the transcription factor CREB, which in turn mediated PCK1 expression. We further demonstrated that PCK1 is an oncogenic factor in lung adenocarcinoma. Given the importance of PCK1 in the regulation of cellular metabolism, we next deciphered the metabolic effects of MLK4. Metabolic and mass spectrometry analyses showed that MLK4 knockdown led to significant reduction of glycolysis and decreased levels of glycolytic pathway metabolites including phosphoenolpyruvate and lactate. Finally, the promoter analysis of MLK4 unravelled a binding site of transcription factor KLF5, which in turn, positively regulated MLK4 expression in lung adenocarcinoma. In summary, we have revealed a KLF5-MLK4-PCK1 signalling pathway involved in lung tumorigenesis and established an unusual link between MAP3K signalling and cancer metabolism.

A metal-to-metal charge transfer induced green-yellow phosphor CsAlGe2O6:Bi3+ for full-spectrum LED devices.

With the development of solid-state lighting, full-spectrum lighting has gradually received extensive attention. Until now, Bi3+-doped narrow-band blue phosphors have been widely reported, but broadband green-yellow Bi3+-doped luminescent materials generated by metal-to-metal charge transfer have been rarely reported. In this study, a Bi3+ ion doped germanate luminescent material CsAlGe2O6:x%Bi3+ (1 ≤ x ≤ 11) is synthesized by a high-temperature sintering method. The phosphor can generate a broad green-yellow band peaking at 535 nm with a full width at half maximum of 165 nm under ultraviolet radiation. Through the analysis of the coordination environment, photoluminescence spectra and decay curves, the broadband emission spectra of Bi3+ ions are proved to be generated by the metal-to-metal charge transfer state and the 3P1 → 1S0 transition. By using theoretical research, luminescence kinetics, and Gaussian fitting, the luminescence mechanism of Bi3+ is examined. Meanwhile, the high quantum efficiency and superior thermal stability prove that the phosphor can be used as an efficient luminescent material in the field of full-spectrum LED devices.

A novel efficient red-emitting K7SrY2B15O30: Eu3+ phosphor with non-concentration quenching and robust thermal stability for white LEDs.

Inhibiting energy migration between Eu3+ ions in a fixed host to get higher doping concentration is a permanent topic. Herein, a novel non-concentration quenching red-emitting K7SrY2-2xB15O30: xEu3+ (0.1 ≤ x ≤ 1.0) phosphor was synthesized via high-temperature sintering method. XRD measurement, Rietveld refinement results, and radius percentage deviation calculation demonstrated the phase purity and the occupation preference of Eu3+ ions. With continuously increasing doping Eu3+ ions, the absence of concentration quenching could be explained by long distance between two Eu3+ (7.012 Å) and the K7SrEu2B15O30 could exhibit striking photoluminescence performance with the highest emission wavelength centered at 617 nm. Meanwhile, under the radiation of 393 nm, the high internal quantum efficiency ( âˆ¼ 78.71 %), excellent color purity ( âˆ¼ 88.32 %) and robust thermal stability whose emission intensity at 140 °C could still reach âˆ¼ 97.31 % could guarantee its potential application. When coating BaMgAl10O17: Eu2+, (Ba, Sr)2SiO4: Eu2+, and K7SrEu2B15O30 on a near-ultraviolet chip, the bright white light with a low correlated color temperature of 4211 K and CIE color coordinates of (0.3675, 0.3556) could be obtained. Taking the analytic results above, the non-concentration quenching K7SrY2B15O30: Eu3+ compound has great potential to act as a candidate for red-emitting phosphors in solid-state lighting field.

Cancer-associated fibroblasts potentiate colorectal cancer progression by crosstalk of the IGF2-IGF1R and Hippo-YAP1 signaling pathways.

Colorectal cancer (CRC) is one of the most common cancers worldwide. The tumor microenvironment exerts crucial effects in driving CRC progression. Cancer-associated fibroblasts (CAFs) serve as one of the most important tumor microenvironment components promoting CRC progression. This study aimed to elucidate the novel molecular mechanisms of CAF-secreted insulin-like growth factor (IGF) 2 in colorectal carcinogenesis. Our results indicated that IGF2 was a prominent factor upregulated in CAFs compared with normal fibroblasts. CAF-derived conditioned media (CM) promoted tumor growth, migration, and invasion of HCT 116 and DLD-1 cells. IGF1R expression is significantly increased in CRC, serving as a potent receptor in response to IGF2 stimulation and predicting unfavorable outcomes for CRC patients. Apart from the PI3K-AKT pathway, RNA-seq analysis revealed that the YAP1-target signature serves as a prominent downstream effector to mediate the oncogenic signaling of IGF2-IGF1R. By single-cell RNA sequencing (scRNA-seq) and immunohistochemical validation, IGF2 was found to be predominantly secreted by CAFs, whereas IGF1R was expressed mainly by cancer cells. IGF2 triggers the nuclear accumulation of YAP1 and upregulates YAP1 target signatures; however, these effects were abolished by either IGF1R knockdown or inhibition with picropodophyllin (PPP), an IGF1R inhibitor. Using CRC organoid and in vivo studies, we found that cotargeting IGF1R and YAP1 with PPP and verteporfin (VP), a YAP1 inhibitor, enhanced antitumor effects compared with PPP treatment alone. In conclusion, this study revealed a novel molecular mechanism by which CAFs promote CRC progression. The findings highlight the translational potential of the IGF2-IGF1R-YAP1 axis as a prognostic biomarker and therapeutic target for CRC. © 2022 The Pathological Society of Great Britain and Ireland.

DUSP5P1 promotes gastric cancer metastasis and platinum drug resistance.

We elucidated the functional significance and molecular mechanisms of DUSP5P1 lncRNA (dual specificity phosphatase 5 pseudogene 1) in gastric carcinogenesis. We demonstrated that gastric cancer (GC) patients with high DUSP5P1 expression had shortened survival in two independent cohorts. DUSP5P1 promoted GC cell migration and invasion in vitro and metastasis in vivo. Mechanistically, DUSP5P1 activated ARHGAP5 transcription by directly binding to the promoter of ARHGAP5 with a binding motif of TATGTG. RNA-seq revealed that ARHGAP5 activated focal adhesion and MAPK signaling pathways to promote GC metastasis. DUSP5P1 also dysregulated platinum drug resistance pathway. Consistently, DUSP5P1 overexpression in GC cells antagonized cytotoxic effect of Oxaliplatin, and shDUSP5P1 plus Oxaliplatin exerted synergistic effect on inhibiting GC metastasis in vitro and in vivo. DUSP5P1 depletion also suppressed the growth of platinum drug-resistant PDO models. In conclusion, DUSP5P1 promoted GC metastasis by directly modulating ARHGAP5 expression to activate focal adhesion and MAPK pathways, serves as therapeutic target for platinum drug resistant GC, and is an independent prognostic factor in GC.

More than a duologue: In-depth insights into epitranscriptomics and ferroptosis.

Beyond transcription, RNA molecules are enzymatically modified to influence the biological functions of living organisms. The term "epitranscriptomics" describes the changes in RNA strands aside from altering the innate sequences. Modifications on adenosine (A) are the most widely characterized epitranscriptomic modification, including N6-methyladenosine (m6A), N1-methyladenosine (m1A), polyadenylation, and adenosine-to-inosine (A-to-I) RNA editing, and modifications on other nucleotides seem to be fewer, such as N7-methylguanosine (m7G), 5-methylcytosine (m5C), and pseudouridine (Ψ). These changes on the RNA strand surface, exclusively by their RNA-modifying proteins (RMPs), are reported in various biological phenomena, including programmed cell death (PCD). One necro-biological phenomenon that has been observed for long but has started to gain heed in recent years is "ferroptosis." The phospholipid peroxidation by polyunsaturated-fatty-acid-containing-phospholipid hydroperoxyl (PLOOH) radicals destroys membrane integrity due to a series of mechanisms. The Fenton reaction, constituting the final Haber-Weiss reaction that is less recognized, collaboratively leading to the conversion of polyunsaturated fatty acid (PUFA) to PLOOH, is the etymological origin of ferroptosis. However, it is with increasing evidence that ferroptotic signaling is also intervened by epitranscriptomic modifications, although the truth is still ambiguous. We attempted to delineate some up-to-date discoveries on both epitranscriptomics and ferroptosis, bringing up the fundamentals to address any potential connection between the two. Next, we discussed whether a duologal relationship, or more, exists between the two, taking the ROS level and iron status into consideration. Lastly, we surveyed future perspectives that would favor the understanding of these topics.

NOTCH3, a crucial target of miR-491-5p/miR-875-5p, promotes gastric carcinogenesis by upregulating PHLDB2 expression and activating Akt pathway.

Aberrant Notch activation has been implicated in multiple malignancies and the identification of NOTCH receptors and related pathways is critical for targeted therapy. In this study, we aim to delineate the most prominent dysregulated NOTCH receptor and comprehensively reveal its deregulation in gastric cancer (GC). In the four Notch members, NOTCH3 was found uniformly upregulated and associated with poor clinical outcomes in multiple GC datasets. siRNA-mediated NOTCH3 knockdown demonstrated antitumor effects by suppressing cell proliferation, inhibiting monolayer formation, and impairing cell invasion abilities. Its depletion also induced early and late apoptosis. NOTCH3 was confirmed to be a direct target of two tumor suppressor microRNAs (miRNAs), namely miR-491-5p and miR-875-5p. The activation of NOTCH3 is partly due to the silence of these two miRNAs. Through RNA-seq profiling and functional validation, PHLDB2 was identified as a potent functional downstream modulator for NOTCH3 in gastric carcinogenesis. PHLDB2 expression demonstrated a positive correlation with NOTCH3, but was negatively correlated with miR-491-5p. Akt-mTOR was revealed as the downstream signaling of PHLDB2. The NOTCH3-PHLDB2-Akt co-activation was found in 33.7% GC patients and the activation of this axis predicted poor clinical outcome. GC cells treated with siNOTCH3, siPHLDB2, miR-491-5p, miR-875-5p, were more sensitive to Cisplatin and 5-FU. Taken together, the NOTCH3-PHLDB2-Akt cascade plays oncogenic role in gastric carcinogenesis and serves as a therapeutic target. Our study provided insights into Notch-mediated underlying molecular mechanisms and implied translational potential.

CYP1A2 suppresses hepatocellular carcinoma through antagonizing HGF/MET signaling.

Rationale: Hyperactivation of HGF/MET signaling pathway is a critical driver in liver tumorigenesis. Cytochrome P450 1A2 (CYP1A2) was significantly down-regulated in hepatocellular carcinoma (HCC). However, little is explored about its tumor suppressive role in HCC. In this study, we examined the functional mechanisms and clinical implication of CYP1A2 in HCC. Methods: The clinical impact of CYP1A2 was evaluated in HCC patients in Hong Kong cohort. The biological functions of CYP1A2 were investigated in vitro and in vivo. A series of biochemical experiments including Western blot assay, immunohistochemistry, quantitative reverse transcription-polymerase chain reaction, and Co-immunoprecipitation assay were conducted. Results: CYP1A2 expression was prominently silenced in HCC tumor tissues and the high expression of CYP1A2 was significantly correlated with lower AFP level, less vascular invasion, and better tumor-free survival in local cohort of HCC patients. The overexpression of CYP1A2 inhibited HCC cell viability and clonogenicity, reduced cell migration and invasion abilities in vitro, and suppressed tumorigenicity in vivo, whereas CYP1A2 knockdown exhibited the opposite effects. CYP1A2 significantly hindered HGF/MET signaling and Matrix metalloproteinases (MMPs) expression in HCC cells. Mechanically, CYP1A2 decreased HGF level and diminished HIF-1α expression, both of which are recognized as key regulators of MET activation. As the transcriptional activator of MET, HIF-1α was identified as a binding partner of CYP1A2. Direct binding of CYP1A2 with HIF-1α induced ubiquitin-mediated degradation of HIF-1α, inhibiting HIF-1α-mediated transcriptions. Conclusions: In conclusion, our results have identified CYP1A2 as a novel antagonist of HGF/MET signaling, and CYP1A2 may serve as an independent new biomarker for the prognosis of HCC patients.

VSTM2A suppresses colorectal cancer and antagonizes Wnt signaling receptor LRP6.

Hyperactivation of Wnt/ß-catenin signaling pathway is a critical step in colorectal tumorigenesis. In this study, we identified that V-set and transmembrane domain containing 2A (VSTM2A) was a top-downregulated secreted protein that negatively regulated Wnt singling pathways in colorectal cancer (CRC). We investigated the functional mechanisms and clinical implication of VSTM2A in CRC. Methods: Function of VSTM2A was investigated in vitro and in vivo. VSTM2A binding partner was identified by mass spectrometry, immunoprecipitation and Western blot. The clinical impact of VSTM2A was assessed in 355 CRC patients and TCGA cohort. Results: VSTM2A protein was prominently silenced in CRC tumor tissues and cell lines mediated by its promoter hypermethylation. VSTM2A DNA promoter hypermethylation and VSTM2A protein downregulation was associated with poor survival of CRC patients. Ectopic expression of VSTM2A inhibited colon cancer cell lines and organoid growth, induced CRC cells apoptosis, inhibited cell migration and invasion, and suppressed growth of xenograft tumors in nude mice. VSTM2A was released from CRC cells through a canonical secretion pathway. Secreted VSTM2A significantly suppressed Wnt signaling pathway in colon cancer cells. Wnt signaling co-receptor LDL receptor related protein 6 (LRP6) was identified as a cell membrane binding partner of VSTM2A. Using deletion/mutation and immunoprecipitation, we demonstrated that VSTM2A bound to LRP6 E1-4 domain with its IgV domain. VSTM2A suppressed LRP6 phosphorylation in a time and dose dependent manner, and induced LRP6 endocytosis and lysosome-mediated degradation, which collectively contributing to the inactivation of Wnt signaling. Conclusions: VSTM2A is a novel antagonist of canonical Wnt signaling by directly binding to LRP6 and induces LRP6 endocytosis and degradation. VSTM2A is a potential prognostic biomarker for the outcome of CRC patients.

Docking protein-1 promotes inflammatory macrophage signaling in gastric cancer.

Docking protein-1 (DOK1) is a tumor suppressor frequently lost in malignant cells, however, it retains the ability to control activities of immune receptors in adjacent stroma cells of the tumor microenvironment. We therefore hypothesized that addressing DOK1 may be useful for cancer immunotherapy. DOK1 mRNA and DOK1 protein expression were downregulated in tumor cells of gastric cancer patients (n = 249). Conversely, its expression was up-regulated in cases positive for Epstein Barr Virus (EBV+) together with genes related to macrophage biology and targets of clinical immunotherapy such as programmed-cell-death-ligand-1 (PD-L1). Notably, high DOK1 positivity in stroma cells conferred poor prognosis in patients and correlated with high levels of inducible nitric oxide synthase in CD68+ tumor-associated macrophages. In macrophages derived from human monocytic leukemia cell lines, DOK1 (i) was inducible by agonists of the anti-diabetic transcription factor peroxisome proliferator-activated receptor-gamma (PPARγ), (ii) increased polarization towards an inflammatory phenotype, (iii) augmented nuclear factor-κB-dependent transcription of pro-inflammatory cytokines and (iv) reduced PD-L1 expression. These properties empowered DOK1+ macrophages to decrease the viability of human gastric cancer cells in contact-dependent co-cultures. DOK1 also reduced PD-L1 expression in human primary blood monocytes. Our data propose that the drugability of DOK1 may be exploited to reprogram myeloid cells and enforce the innate immune response against EBV+ human gastric cancer.

C8orf76 Promotes Gastric Tumorigenicity and Metastasis by Directly Inducing lncRNA DUSP5P1 and Associates with Patient Outcomes.

PURPOSE: We identified for the first time that C8orf76 (chromosome 8 open reading frame 76) is preferentially amplified in gastric cancer. We elucidated its role and clinical significance in gastric carcinogenesis. EXPERIMENTAL DESIGN: The clinical impact of C8orf76 was assessed in 592 patients with gastric cancer. The biological function of C8orf76 was studied in vitro, in vivo, and in gastric cancer patient-derived organoid models. C8orf76 downstream effector and pathways were identified by RNA sequencing, chromatin immunoprecipitation sequencing, luciferase reporter, and electrophoretic mobility shift assay. RESULTS: C8orf76 was upregulated in 69.74% and 65.71% of two independent cohorts of gastric cancers and was positively associated with C8orf76 amplification. Multivariate analysis showed that gastric cancer patients with C8orf76 amplification (cohort I, n = 129; cohort II, n = 107) or overexpression (n = 356) had a significantly shortened survival. C8orf76 significantly promoted gastric cancer cell proliferation, cell-cycle transformation, and migration/invasion, but suppressed cell apoptosis. Silencing C8orf76 expression exerted opposite effects in vitro and significantly inhibited xenograft tumor growth, lung metastasis, and liver metastasis in nude mice. Silencing C8orf76 also significantly suppressed the growth of patient-derived organoids. Mechanically, C8orf76 activated MAPK/ERK signaling cascade. C8orf76 directly bound to the promoter region of lncRNA dual specificity phosphatase 5 pseudogene 1 (DUSP5P1) with a binding motif of AGGCTG and activated DUSP5P1 transcription. DUSP5P1 induced MAPK/ERK signaling and promoted gastric tumorigenesis. Knockdown DUSP5P1 abrogated the effect of C8orf76 in activating MAPK/ERK cascade and the tumor-promoting function. CONCLUSIONS: C8orf76 directly binds to oncogenic lncRNA DUSP5P1 to induce its expression and activates MAPK signaling. C8orf76 plays a pivotal oncogenic role in gastric carcinogenesis and is an independent prognostic factor for gastric cancer patients.

FGF18, a prominent player in FGF signaling, promotes gastric tumorigenesis through autocrine manner and is negatively regulated by miR-590-5p.

Fibroblast growth factors (FGFs) and their receptors are significant components during fundamental cellular processes. FGF18 plays a distinctive role in modulating the activity of both tumor cells and tumor microenvironment. This study aims to comprehensively investigate the expression and functional role of FGF18 in gastric cancer (GC) and elucidate its regulatory mechanisms. The upregulation of FGF18 was detected in seven out of eleven (63.6%) GC cell lines. In primary GC samples, FGF18 was overexpressed in genomically stable and chromosomal instability subtypes of GC and its overexpression was associated with poor survival. Knocking down FGF18 inhibited tumor formation abilities, induced G1 phase cell cycle arrest and enhanced anti-cancer drug sensitivity. Expression microarray profiling revealed that silencing of FGF18 activated ATM pathway but quenched TGF-ß pathway. The key factors that altered in the related signaling were validated by western blot and immunofluorescence. Meanwhile, treating GC cells with human recombinant FGF18 or FGF18-conditioned medium accelerated tumor growth through activation of ERK-MAPK signaling. FGF18 was further confirmed to be a direct target of tumor suppressor, miR-590-5p. Their expressions showed a negative correlation in primary GC samples and more importantly, re-overexpression of FGF18 partly abolished the tumor-suppressive effect of miR-590-5p. Our study not only identified that FGF18 serves as a novel prognostic marker and a therapeutic target in GC but also enriched the knowledge of FGF-FGFR signaling during gastric tumorigenesis.

First-Principles Determination of Active Sites of Ni Metal-Based Electrocatalysts for Hydrogen Evolution Reaction.

The determination of active sites of materials is essential for the molecular design of high-performance catalysts. In this study, the first-principles method is applied to investigate the active sites of low-cost Ni metal-based electrocatalysts for hydrogen evolution reactions (HER), which is a promising alternative to expensive Pt metal-based catalysts. The adsorption of hydrogen on different sites of pristine and partially oxidized Ni(111) surface is investigated. All of the possible configurations have been systematically investigated here with the consideration of their Boltzmann distribution. Using the Gibbs free energy of intermediate H atoms (Δ GH*) as a descriptor, it is found that the Δ GH* increases with the increase of the coverage of oxygen atoms. The slightly oxidized surface Ni atoms are theoretically identified to be the best catalytic centers for the electrocatalytic HERs when the coverage of oxygen is considerably low. On the basis of the analyses of Bader charge distribution and density of states, our results reveal that the superior performance of the slightly oxidized surface Ni atoms can be ascribed to the optimal electronic properties.

Specific targeting of point mutations in EGFR L858R-positive lung cancer by CRISPR/Cas9.

Cancer cells are defined genetically by the mutations they harbor, commonly single nucleotide substitutions. Therapeutic approaches which specifically target cancer cells by recognizing these defining genetic aberrations are expected to exhibit minimal side-effects. However, current protein-based targeted therapy is greatly limited by the range of genes that can be targeted, as well as by acquired resistance. We hypothesized that a therapeutic oligonucleotide-based strategy may address this need of specific cancer targeting. We used CRISPR/Cas9 system to target a commonly occurring EGFR point mutation, L858R, with an oligonucleotide guide that recognizes L858R as the suitable protospacer-adjacent motif (PAM) sequence for DNA cleavage. We found that this strategy, which utilized PAM to differentiate cancer mutation from normal, afforded high specificity to the extent of a single nucleotide substitution. The anti-L858R vehicle resulted in selective genome cleavage only in L858R mutant cells, as detected by Sanger sequencing and T7 Endonuclease I assay. Wild-type cells were unaffected by the same treatment. Digital PCR revealed 37.9 ± 8.57% of L858R gene copies were targeted in mutant. Only treated mutant cells, but not wild-type cells, showed reduction in EGFR expression and decreased cell proliferation. Treated mutant cells also formed smaller tumor load in vivo. This targeting approach is expected to be able to target a significant subset of the 15-35% cancer mutations with C > G, A > G, and T > G point mutations. Thus, this strategy may serve as a useful approach to target cancer-defining mutations with specificity, to the extent of differentiating the change of a single nucleotide.

CREPT facilitates colorectal cancer growth through inducing Wnt/ß-catenin pathway by enhancing p300-mediated ß-catenin acetylation.

Using whole genome sequencing, we identified gene amplification of CREPT in colorectal cancer (CRC). In this study, we aim to clarify its clinical significance, biological effects, and mechanism in CRC. CREPT was upregulated in CRC cell lines and in 47.37% (72/152) of primary CRC tumors. Amplification of CREPT was detected in 48.28% (56/116) of primary CRC tumors, which was positively correlated with its overexpression (P < 0.001). Multivariate analysis showed that CRC patients with CREPT protein overexpression were significantly associated with poor disease-free survival (P < 0.05). CREPT significantly accelerated CRC cell proliferation and metastasis both in vitro and in vivo. RNA-sequencing (seq) analysis uncovered that the tumor-promoting effect by CREPT was attributed to enhancing Wnt/ß-catenin signaling. Using co-immunoprecipitation coupled with mass spectroscopy, we identified p300 protein was a novel CREPT interacting partner. CREPT greatly increased the interaction between p300 and ß-catenin, thus promoting p300-mediated ß-catenin acetylation and stabilization. Moreover, CREPT cooperated with p300, leading to elevated active histone acetylation markers H3K27ac and H4Ac and decreased repressive histone marker H3K9me3 at the promoters of Wnt downstream targets. In summary, CREPT plays a pivotal oncogenic role in colorectal carcinogenesis through promoting Wnt/ß-catenin pathway via cooperating with p300. CREPT may serve as a prognostic biomarker of patients with CRC.

Synergistic Nanotubular Copper-Doped Nickel Catalysts for Hydrogen Evolution Reactions.

Developing highly active electrocatalysts with low cost and high efficiency for hydrogen evolution reactions (HERs) is of great significance for industrial water electrolysis. Herein, a 3D hierarchically structured nanotubular copper-doped nickel catalyst on nickel foam (NF) for HER is reported, denoted as Ni(Cu), via facile electrodeposition and selective electrochemical dealloying. The as-prepared Ni(Cu)/NF electrode holds superlarge electrochemical active surface area and exhibits Pt-like electrocatalytic activity for HER, displaying an overpotential of merely 27 mV to achieve a current density of 10 mA cm-2 and an extremely small Tafel slope of 33.3 mV dec-1 in 1 m KOH solution. The Ni(Cu)/NF electrode also shows excellent durability and robustness in both continuous and intermittent bulk water electrolysis. Density functional theory calculations suggest that Cu substitution and the formation of NiO on the surface leads to more optimal free energy for hydrogen adsorption. The lattice distortion of Ni caused by Cu substitution, the increased interfacial activity induced by surface oxidation of nanoporous Ni, and numerous active sites at Ni atom offered by the 3D hierarchical porous structure, all contribute to the dramatically enhanced catalytic performance. Benefiting from the facile, scalable preparation method, this highly efficient and robust Ni(Cu)/NF electrocatalyst holds great promise for industrial water-alkali electrolysis.

miR-375 is involved in Hippo pathway by targeting YAP1/TEAD4-CTGF axis in gastric carcinogenesis.

miR-375 is a tumor-suppressive microRNA (miRNA) in gastric cancer (GC). However, its molecular mechanism remains unclear. The aim of this study is to comprehensively investigate how miR-375 is involved in Hippo pathway by targeting multiple oncogenes. miR-375 expression in gastric cancer cell lines and primary GC was investigated by qRT-PCR. The regulation of YAP1, TEAD4, and CTGF expression by miR-375 was evaluated by qRT-PCR, western blot, and luciferase reporter assays, respectively. The functional roles of the related genes were examined by siRNA-mediated knockdown or ectopic expression assays. The clinical significance and expression correlation analysis of miR-375, YAP1, and CTGF were performed in primary GCs. TCGA cohort was also used to analyze the expression correlation of YAP1, TEAD4, CTGF, and miR-375 in primary GCs. miR-375 was down-regulated in GC due to promoter methylation and histone deacetylation. miR-375 downregulation was associated with unfavorable outcome and lymph node metastasis. Ectopic expression of miR-375 inhibited tumor growth in vitro and in vivo. Three components of Hippo pathway, YAP1, TEAD4 and CTGF, were revealed to be direct targets of miR-375. The expression of three genes showed a negative correlation with miR-375 expression and YAP1 re-expression partly abolished the tumor-suppressive effect of miR-375. Furthermore, CTGF was confirmed to be the key downstream of Hippo-YAP1 cascade and its knockdown phenocopied siYAP1 or miR-375 overexpression. YAP1 nuclear accumulation was positively correlated with CTGF cytoplasmic expression in primary GC tissues. Verteporfin exerted an anti-oncogenic effect in GC cell lines by quenching CTGF expression through YAP1 degradation. In short, miR-375 was involved in the Hippo pathway by targeting YAP1-TEAD4-CTGF axis and enriched our knowledge on the miRNA dysregulation in gastric tumorigenesis.