Significantly Enhanced Energy-Saving H2 Production Coupled with Urea Oxidation by Low- and Non-Pt Anchored on NiS-Based Conductive Nanofibers.

Rational designing electrocatalysts is of great significance for realizing high-efficiency H2 production in the water splitting process. Generally, reducing the usage of precious metals and developing low-potential nucleophiles oxidation reaction to replace anodic oxygen evolution reaction (OER) are efficient strategies to promote H2 generation. Here, NiS-coated nickel-carbon nanofibers (NiS@Ni-CNFs) are prepared for low-content Pt deposition (Pt-NiS@Ni-CNFs) to attain the alkaline HER catalyst. Due to the reconfiguration of NiS phase and synergistic effect between Pt and nickel sulfides, the Pt-NiS@Ni-CNFs catalyst shows a high mass activity of 2.74-fold of benchmark Pt/C sample. In addition, the NiS@Ni-CNFs catalyst performs a superior urea oxidation reaction (UOR) activity with the potential of 1.366 V versus reversible hydrogen electrode (RHE) at 10 mA cm-2 , which demonstrates the great potential in the replacement of OER. Thus, a urea-assisted water splitting electrolyzer of Pt-NiS@Ni-CNFs (cathode)||NiS@Ni-CNFs (anode) is constructed to exhibit small voltages of 1.44 and 1.65 V to reach 10 and 100 mA cm-2 , which is much lower than its overall water splitting process, and presents a 6.5-fold hydrogen production rate enhancement. This work offers great opportunity to design new catalysts toward urea-assisted water splitting with significantly promoted hydrogen productivity and reduced energy consumption.

High-resolution mass spectrometry-based screening and dietary intake assessment of organophosphate esters in foodstuffs from South China.

Organophosphate esters (OPEs) are a group of emerging contaminants with widespread environmental occurrence, yet research on their occurrence in foodstuffs is limited. We collected 100 foodstuff samples in South China using a market basket method, and analyzed food extracts for the presence of OPEs and organophosphite antioxidants (OPAs) by suspect and nontarget screening through high-resolution mass spectrometry. Our analysis resulted in the identification of 30 OPEs, comprised of 25 OPEs with a confidence level (CL) of 1 (unequivocal identification using standards) and five OPEs with CL = 2b (probable structure based on diagnostic evidence). Interestingly, 11 of these identified OPEs had not been previously reported in food. No OPA was identified. The occurrence of identified OPEs within the food samples was further investigated. The highest median concentration of OPEs in all food samples was reached by tris(2-chloroisopropyl) phosphate (TCPP) (1.55 ng/g ww, range < 0.74-12.0 ng/g wet weight (ww)). Cereals demonstrated the highest median concentration of the cumulative 30 OPEs. Tris(2-chloroethyl) phosphate (TCEP), TCPP, and triethyl phosphate (TEP) predominantly contributed to OPEs contamination in most food categories. Eight OPEs, namely TEP, tris(2-ethylhexyl) phosphate (TEHP), TCEP, triphenyl phosphate (TPhP), 2-ethylhexyl diphenyl phosphate (EHDPP), bis(2-ethylhexyl) phenyl phosphate (BEHPP), resorcinol bis(diphenyl phosphate) (RDP), and methyl diphenyl phosphate (MDPP) exhibited significantly higher concentrations in the processed group as compared to non-processed group, suggesting that food processing may result in contamination of these OPEs. The median sum of estimated dietary intake (ΣEDI) of all OPEs was determined to be 161 ng/kg body weight/day. Cereals (38.5 %) and vegetables (23.5 %) were the predominant food categories contributing to ΣEDI, and TEP (29.0 %), TCEP (20.2 %), and TCPP (18.3 %) were three major OPEs contributing to ΣEDI. This study for the first time offered a comprehensive overview of OPE species and revealed their occurrence in foodstuffs from South China.

BSN-ESC: A Big-Small Network-Based Environmental Sound Classification Method for AIoT Applications.

In recent years, environmental sound classification (ESC) has prevailed in many artificial intelligence Internet of Things (AIoT) applications, as environmental sound contains a wealth of information that can be used to detect particular events. However, existing ESC methods have high computational complexity and are not suitable for deployment on AIoT devices with constrained computing resources. Therefore, it is of great importance to propose a model with both high classification accuracy and low computational complexity. In this work, a new ESC method named BSN-ESC is proposed, including a big-small network-based ESC model that can assess the classification difficulty level and adaptively activate a big or small network for classification as well as a pre-classification processing technique with logmel spectrogram refining, which prevents distortion in the frequency-domain characteristics of the sound clip at the joint part of two adjacent sound clips. With the proposed methods, the computational complexity is significantly reduced, while the classification accuracy is still high. The proposed BSN-ESC model is implemented on both CPU and FPGA to evaluate its performance on both PC and embedded systems with the dataset ESC-50, which is the most commonly used dataset. The proposed BSN-ESC model achieves the lowest computational complexity with the number of floating-point operations (FLOPs) of only 0.123G, which represents a reduction of up to 2309 times in computational complexity compared with state-of-the-art methods while delivering a high classification accuracy of 89.25%. This work can achieve the realization of ESC being applied to AIoT devices with constrained computational resources.

The effects of text direction of different text lengths on Chinese reading.

This study investigates the effects of text direction (horizontal and vertical) and length (long and short) on Chinese reading performance. The experiment enrolled 68 university students aged 19-29 years who were asked to read articles. We recorded reading times and measured recall after reading using a memory test and measured task load using the NASA-TLX scale. The results show that horizontal text was read faster than vertical text. When reading long texts, horizontal reading has a better memory effect than vertical reading. When reading short texts, the effect of text direction on memory was not significant. Moreover, the mental, physical, and temporal demands of horizontal text were lower than those of vertical text. These findings contribute to a better understanding of the impact of text direction, provide valuable suggestions for Chinese typography, and help readers obtain better reading outcomes.

Modeling and Simulation of Autonomous Inflow Control Devices for Gas Exploitation.

Horizontal well technology is an efficient method of oil and gas exploitation. The goal of increasing oil production and improving productivity can be achieved by increasing the contact area between the reservoir and the wellbore. The presence of bottom water cresting reduces the efficiency of oil and gas production significantly. Autonomous inflow control devices (AICDs) are widely used to delay the influx of water into the wellbore. Two kinds of AICDs are proposed to restrain the bottom water breakthrough during natural gas production. The fluid flows in the AICDs are simulated numerically. The pressure difference between the inlet and outlet is calculated to evaluate the ability of blocking the flow. A dual-inlet design can increase the flow rate of AICDs, thus enhancing the water blocking effect. Numerical simulations show that the devices can block water flowing into the wellbore effectively.

A Comprehensive Review of Natural Flavonoids with Anti-SARS-CoV-2 Activity.

The COVID-19 pandemic caused by SARS-CoV-2 has majorly impacted public health and economies worldwide. Although several effective vaccines and drugs are now used to prevent and treat COVID-19, natural products, especially flavonoids, showed great therapeutic potential early in the pandemic and thus attracted particular attention. Quercetin, baicalein, baicalin, EGCG (epigallocatechin gallate), and luteolin are among the most studied flavonoids in this field. Flavonoids can directly or indirectly exert antiviral activities, such as the inhibition of virus invasion and the replication and inhibition of viral proteases. In addition, flavonoids can modulate the levels of interferon and proinflammatory factors. We have reviewed the previously reported relevant literature researching the pharmacological anti-SARS-CoV-2 activity of flavonoids where structures, classifications, synthetic pathways, and pharmacological effects are summarized. There is no doubt that flavonoids have great potential in the treatment of COVID-19. However, most of the current research is still in the theoretical stage. More studies are recommended to evaluate the efficacy and safety of flavonoids against SARS-CoV-2.

NiCo2S4 combined 3D hierarchical porous carbon derived from lignin for high-performance supercapacitors.

Metal sulfides with the nature of low electronegativity and high electrochemical activity are potentially considered effective electrode materials for supercapacitors. Meanwhile, hierarchical porous carbon (HPC) materials derived from eco-friendly enzymatic hydrolysis lignin are the ideal matrix for holding nanoparticles (NP) that allows the overall NP/HPC composite to achieve outstanding electrochemical performance. In this study, NiCo2S4 nanoparticles were in-situ synthesized on the inner surface of 3D HPC that derived from enzymatic hydrolysis lignin with a simple one-step solvothermal method, thus forming a high-performance composite electrode material for supercapacitor applications. As a result, the NiCo2S4/HPC composite yields an outstanding specific capacity of 1264.2 F g-1 at 1 A g-1 and also exhibits remarkable rate performance. Such remarkable property is attributed to the effective combination of NiCo2S4 plus HPC and their strong chemical bonds, which enable excellent electronic conductivity and abundant exposed electroactive sites. The asymmetric supercapacitor assembled by utilizing NiCo2S4/HPC and active carbon as the positive and negative electrodes, respectively, provide an excellent energy density of 32.05 Wh kg-1 at a power density of 193.9 W kg-1. This work puts forward a practical optimization strategy for metal sulfides used in electrochemical energy storage devices.

A point-to-point "cap" strategy to construct a highly selective dual-function molecularly-imprinted sensor for the simultaneous detection of HAV and HBV.

As an artificial biomimetic receptor, molecularly-imprinted polymer (MIP) has been widely used for the separation, enrichment and detection of various substances. However, due to the complexity of virus structure, huge volume and the existence of highly similar viruses, MIP shows unsatisfactory selectivity in virus detection. To overcome these issues, two kinds of virus nanoMIPs, just like a "cap", were synthesized by a solid-phase imprinting nanogel technique. The "cap" had no inner core and was much smaller than that of a conventional MIP, which was more favorable for mass transfer. Moreover, each "cap" could only combine with one target virus, which avoided the interference between large-volume virus molecules effectively. The two synthesized "caps" were mixed to construct a bifunctional MIP virus sensor for the simultaneous detection of Hepatitis A virus (HAV) and Hepatitis B virus (HBV). As expected, the selectivity factor (SF) for HBV detection reached 13.7, which was much higher than the reported virus MIP sensors (SF: 3-6), which was comparable to that of small molecular imprinting sensors. In addition, the high sensitivity toward HBV was 34.3 fM, and that of HAV was 27.1 pM. This method provides an idea for preparing high-selectivity biomacro-MIPs, as well as a method for the simultaneous detection of similar viruses with high sensitivity and selectivity. The recovery experiment of spiked serum showed that this method also has great practical application prospects.

Constructing a Ring-like Self-Aggregation SERS Sensor with the Coffee Ring Effect for Ultrasensitive Detection and Photocatalytic Degradation of the Herbicides Paraquat and Diquat.

A strategy for building ring-like deposit surface-enhanced Raman scattering (SERS) sensors with the coffee ring effect through the functional modification of the silica nanoparticle surface encapsulated by free-tagged Ag nanoparticles is addressed along with their applications in the SERS-based detection and degradation of target species, including paraquat, diquat, and their free radicals. The nanogap formed by two interparticles with SERS hotspots provides a gigantic amplification signal for the Raman scattering intensity of the analyte molecule located approximately at the hotspots. The enhanced Raman spectrum signals of these target analytes were achieved through the hotspot region of the surface plasmon resonance (SPR) located on the embankment formed by self-aggregation of SiO2@Ag nanoparticles due to the coffee ring effect. Meanwhile, the intrinsic properties of Ag nanoparticles embedded onto the silica surface were applied to photocatalytically degrade the target analytes by harvesting energy from sunlight. The SERS sensor detected the analytes down to 10-9 M in the aqueous solution.

MiR-190 ameliorates glucotoxicity-induced dysfunction and apoptosis of pancreatic ß-cells by inhibiting NOX2-mediated reactive oxygen species production.

Glucotoxicity-induced pancreatic ß-cell failure contributes to the development of type 2 diabetes mellitus (T2DM). Accumulating evidence reveals that miRNAs play a critical role in regulating pancreatic ß-cell function and survival. In this study, we employed a self-assembled cell microarray (SAMcell)-based functional screening assay to identify miRNAs that are capable of regulating the dysfunction of ß-cells induced by glucotoxicity. Among 62 conserved miRNAs we tested, miR-190 was identified as a candidate regulator that could effectively restore insulin expression in NIT-1 cells under high-glucose (HG) stimulation. Further analyses demonstrated that miR-190 was significantly down-regulated in HG-treated NIT-1 cells, as well as in the pancreas of diabetic mice. Mechanistic studies showed that Cybb is the direct target gene of miR-190, which encodes the gp91phox protein, a subunit of the NOX2 complex. Furthermore, both miR-190 overexpression and Cybb knockdown inhibited apoptosis and improved glucose-stimulated insulin secretion (GSIS) in HG-stimulated NIT-1 cells by attenuating the excessive production of reactive oxygen species (ROS). More importantly, a targeted delivery of mPEG-PCL-g-PDMAEMA nanoparticles/miR-190 complexes (PECgD NPs/miR-190) to the pancreas significantly ameliorated hyperglycemia, decreased fasting serum insulin levels, and improved glucose tolerance in diabetic mice. Taken together, our findings suggest that the miR-190/Cybb axis plays an important role in glucotoxicity-induced pancreatic ß-cell failure. Restoring miR-190 expression levels may be a possible therapeutic strategy to protect ß-cells in T2DM.

Preliminary Application of Magnetization Transfer Imaging in the Study of Normal Uterus and Uterine Lesions.

Purpose: The aim of this study is to evaluate the utility of magnetization transfer (MT) imaging in the study of normal uterus and common uterine lesions. Methods: This prospective study enrolled 160 consecutive patients with suspected uterine lesions. MT ratio (MTR) map was obtained by pelvic MT imaging on a 3.0T MRI scanner. Patients confirmed by pathology were divided into microscopic lesion group and lesion group, according to whether the maximum diameter of the lesion was less than 5 mm. After evaluating and eliminating patients with poor image quality by a three-point Likert scale, MTR values of lesions and normal endometrium, myometrium, and cervix were independently measured on the MTR map by two radiologists. Inter-reader agreement was evaluated. MTR values were compared among different uterine lesions and normal uterine structures using the Mann-Whitney U test with Bonferroni correction. Receiver operating characteristic curve was performed. The correlations between age and MTR values were explored by Pearson correlation analyses. Results: A total of 96 patients with 121 uterine lesions in the lesion group and 41 patients in the microscopic lesion group were measured. The MTR values among normal endometrium, myometrium, and cervix were statistical significant differences (P < 0.05). There were significant differences between endometrial cancer and normal endometrium and between cervical cancer and normal cervix (both P ≤ 0.001). Area under the curve (AUC) for diagnosing endometrial and cervical cancer were 0.73 and 0.86. Myometrial lesions had significantly higher MTR values than endometrial lesions and cervical cancer (both P < 0.001), and the AUC for differentiating myometrial lesions from them were 0.89 and 0.94. MTR values of endometrial cancer were significantly higher than those of cervical cancer (P = 0.02). There was a critical correlation between age and MTR values in endometrial cancer (r = 0.81, P = 0.04). Conclusions: MTR values showed significant differences among normal uterine structures. It was valuable for diagnosing and differentiating uterine cancer. MTR values could differentiate myometrial lesions from endometrial or cervical lesions.

Exogenous expression of barley HvWRKY6 in wheat improves broad-spectrum resistance to leaf rust, Fusarium crown rot, and sharp eyespot.

Systemic acquired resistance (SAR) is a broad-spectrum plant defense phenomena controlled by the salicylic acid receptor NPR1. Key regulators of the SAR signaling pathway showed great potentials to improve crop resistance to various diseases. In our previous investigation, a barley transcription factor gene HvWRKY6 was identified as downstream of NPR1 during SAR. However, the broad-spectrum resistance features and molecular mechanisms of HvWRKY6 remain to be explored. In this study, a transgenic wheat line exogenously expressing HvWRKY6 showed improved resistance to leaf rust, Fusarium crown rot (FCR), and sharp eyespot. The model pathogen Pseudomonas syringae pv. tomato DC3000 was employed to induce the SAR response in wheat plants' leaf region adjacent to the infiltration area. Transcriptome sequencing revealed activation of broad-spectrum defense responses by expressing HvWRKY6 in a pathogen-independent manner. Based on the differentially expressed genes in plant hormone signal transduction, we speculated that the enhanced resistance in HvWRKY6-OE wheat transgenic line was associated with activation of the salicylic acid pathway and suppression of the abscisic acid and jasmonic acid pathways. These findings suggest that the transgenic line HvWRKY6-OE might be applied for the genetic improvement of wheat to several fungal diseases; the underlying resistance mechanism was clarified.

Comparative Analysis of the Microbial Community Structures Between Healthy and Anthracnose-Infected Strawberry Rhizosphere Soils Using Illumina Sequencing Technology in Yunnan Province, Southwest of China.

Anthracnose caused by Colletotrichum spp. was widespread in recent years and resulted in great damage to strawberry production. Soil microbial communities were key contributors to host nutrition, development, and immunity; however, the difference between the microbial communities of healthy and anthracnose-infected strawberry rhizosphere soils remains unclear. In this study, the Illumina sequencing technique was used to comparatively study the prokaryotic and fungal community compositions and structures between healthy and anthracnose-infected strawberry rhizosphere soils in Yuxi, Yunnan Province. Both microbial community diversities and richness of anthracnose-infected strawberry rhizosphere soils were higher than those of healthy strawberry rhizosphere soils. A total of 2,518 prokaryotic and 556 fungal operational taxonomic units (OTUs) were obtained at the 97% similarity threshold. Proteobacteria, Thaumarchaeota, and Acidobacteria were the dominant prokaryotic phyla; Ascomycota, unclassified_k__Fungi, and Mortierellomycota were the dominant fungal phyla. The relative abundances of beneficial bacterial phyla Actinobacteria and Firmicutes, genera Streptomyces, Azospirillum, and Bacillus were significantly reduced in anthracnose-infected strawberry rhizosphere soils; the relative abundance of beneficial fungal species Trichoderma asperellum shows a similar tendency with bacterial abundance. Besides Colletotrichum, 15 other potential fungal pathogen genera and seven fungal pathogen species were identified; among the potential pathogen genera and species, eight pathogen genera and Fusarium oxysporum showed significant differences between healthy and anthracnose-infected strawberry rhizosphere soils. The results suggested that strawberry planted in this area may be infected by other fungal pathogens except for Colletotrichum spp. Our present research will provide theoretical basis and data reference for the isolation and identification of strawberry pathogens and potential probiotics in future works.

Comparative investigation of a lattice Boltzmann boundary treatment of multiphase mass transport with heterogeneous chemical reactions.

Multiphase reactive transport in porous media is an important component of many natural and engineering processes. In the present study, boundary schemes for the continuum species transport-lattice Boltzmann (CST-LB) mass transport model and the multicomponent pseudopotential model are proposed to simulate heterogeneous chemical reactions in a multiphase system. For the CST-LB model, a lattice-interface-tracking scheme for the heterogeneous chemical reaction boundary is provided. Meanwhile, a local-average virtual density boundary scheme for the multicomponent pseudopotential model is formulated based on the work of Li et al. [Li, Yu, and Luo, Phys. Rev. E 100, 053313 (2019)10.1103/PhysRevE.100.053313]. With these boundary treatments, a numerical implementation is put forward that couples the multiphase fluid flow, interfacial species transport, heterogeneous chemical reactions, and porous matrix structural evolution. A series of comparison benchmark cases are investigated to evaluate the numerical performance for different pseudopotential wetting boundary treatments, and an application case of multiphase dissolution in porous media is conducted to validate the present models' ability to solve complex problems. By applying the present LB models with reasonable boundary treatments, multiphase reactive transport in various natural or engineering scenarios can be simulated accurately.

Demethylation and Up-Regulation of an Oncogene after Hypomethylating Therapy.

BACKGROUND: Although hypomethylating agents are currently used to treat patients with cancer, whether they can also reactivate and up-regulate oncogenes is not well elucidated. METHODS: We examined the effect of hypomethylating agents on SALL4, a known oncogene that plays an important role in myelodysplastic syndrome and other cancers. Paired bone marrow samples that were obtained from two cohorts of patients with myelodysplastic syndrome before and after treatment with a hypomethylating agent were used to explore the relationships among changes in SALL4 expression, treatment response, and clinical outcome. Leukemic cell lines with low or undetectable SALL4 expression were used to study the relationship between SALL4 methylation and expression. A locus-specific demethylation technology, CRISPR-DNMT1-interacting RNA (CRISPR-DiR), was used to identify the CpG island that is critical for SALL4 expression. RESULTS: SALL4 up-regulation after treatment with hypomethylating agents was observed in 10 of 25 patients (40%) in cohort 1 and in 13 of 43 patients (30%) in cohort 2 and was associated with a worse outcome. Using CRISPR-DiR, we discovered that demethylation of a CpG island within the 5' untranslated region was critical for SALL4 expression. In cell lines and patients, we confirmed that treatment with a hypomethylating agent led to demethylation of the same CpG region and up-regulation of SALL4 expression. CONCLUSIONS: By combining analysis of patient samples with CRISPR-DiR technology, we found that demethylation and up-regulation of an oncogene after treatment with a hypomethylating agent can indeed occur and should be further studied. (Funded by Associazione Italiana per la Ricerca sul Cancro and others.).

First report of Calonectria canadiana causing peach fruit rot in China.

Peach (Prunus persica (L.) Batsch) is one of the most popular fruits grown in Northern China. In July 2021, a fruit rot outbreak on the peach cultivar "Yonglian Sweet" occurred after unusual rains in Baoding, Hebei Province, China. Sixty peach trees from three orchards were assessed, and a 30% disease incidence was estimated. The disease initiated as a small concave spot on the fruit surface expanding circularly rotting the fruit (3-5 cm deep) with the appearance of grayish-white mycelia (Figure S1A). The infected fruit did not disintegrate but turned light brown. To identify the pathogen, 20 infected fruits were collected, and fruit tissues from lesion margins were inoculated on the potato dextrose agar (PDA) medium. A total of 15 fungal pure cultures with highly similar morphological characteristics were obtained by the hyphal-tipping method. The fungal culture formed smooth-edged colonies of extensive, dense, wooly aerial mycelium, with color changing from sienna to luteous, and to grayish-white along the radius of colonies (Figure S1B) Chlamydospores were extensive and developed micro-sclerotia after 20 d of growth. The conidiophore produced three branches in a "broom" shape, with the primary branch ranging 7.5-25.0 µm in length, the secondary branch 5.5-15.5 µm, and the tertiary branch 10-12.5 µm (N = 30). The top of the tertiary branch tapered and produced conidia. Conidia were colorless and culm-like, 40.0-57.5 µm long and 3.8-6.25 µm wide (N = 30). Hyphae occasionally produced spherical chlamydospores with a diameter of around 7.5 µm (N = 30). Conidia germinated after 12 h in moist conditions, and germ tubes originated from multiple points on the conidia. Based on these morphological features, the isolated fungus was identified as Calonectria spp. (Lombard et al. 2010). Six loci, including ITS, act, cmdA, his3, tef1, and tub2, were amplified and sequenced for molecular identification of an isolate F099 using primers listed in Table S1. The obtained ITS (528 bp, GenBank accession no. OL635556), act (263 bp, OL694221), cmdA (470 bp, OL694222), his3 (432 bp, OL694223), tef1 (487 bp, OL694224), and tub2 (535 bp, OL694225) sequences showed 100% similarity to the ex-type strain of Calonectria canadiana, CMW 23673 (accession nos. MT359667, MT334976, MT335206, MT335446, MT412737, and MT412958, respectively; Figure S1D) (Kang et al. 2001, Lechat et al. 2010, Liu et al. 2020). The isolate F099 of C. canadiana was further subjected to pathogenicity tests. Koch's postulates were performed by placing three mycelial disks (ten-day old, 5 mm) with conidia on the sterile needle-acupunctured surface of healthy fruits of the peach cultivar "Yonglian Sweet" (N= 10). Mock inoculations with sterile PDA disks were served as a control. All the inoculated fruits were kept in a moist chamber (25℃, 16-h light and 8-h dark period). The inoculation assay was repeated twice. Rotting symptoms developed on all the inoculated fruits about 5 days post-inoculation (dpi) and grayish-white mycelia appeared around ten days post inoculation while mock inoculated fruits did not show any rotting. The pathogen of interest was re-isolated from the inoculated fruits and validated as C. canadiana by ITS and tef1 sequences. All above evidence collectively indicates that the fungal pathogen causing the peach fruit rot is C. canadiana. The new host plant and new geographic distribution reported here will inform future management of this fungal species.

Pseudogene-mediated DNA demethylation leads to oncogene activation.

Pseudogenes, noncoding homologs of protein-coding genes, once considered nonfunctional evolutionary relics, have recently been linked to patient prognoses and cancer subtypes. Despite this potential clinical importance, only a handful of >12,000 pseudogenes in humans have been characterized in cancers to date. Here, we describe a previously unrecognized role for pseudogenes as potent epigenetic regulators that can demethylate and activate oncogenes. We focused on SALL4, a known oncogene in hepatocellular carcinoma (HCC) with eight pseudogenes. Using a locus-specific demethylating technology, we identified the critical CpG region for SALL4 expression. We demonstrated that SALL4 pseudogene 5 hypomethylates this region through interaction with DNMT1, resulting in SALL4 up-regulation. Intriguingly, pseudogene 5 is significantly up-regulated in a hepatitis B virus model before SALL4 induction, and both are increased in patients with HBV-HCC. Our results suggest that pseudogene-mediated demethylation represents a novel mechanism of oncogene activation in cancer.

Targeting an Inducible SALL4-Mediated Cancer Vulnerability with Sequential Therapy.

Oncofetal protein SALL4 is critical for cancer cell survival. Targeting SALL4, however, is only applicable in a fraction of cancer patients who are positive for this gene. To overcome this limitation, we propose to induce a cancer vulnerability by engineering a partial dependency upon SALL4. Following exogenous expression of SALL4, SALL4-negative cancer cells became partially dependent on SALL4. Treatment of SALL4-negative cells with the FDA-approved hypomethylating agent 5-aza-2'-deoxycytidine (DAC) resulted in transient upregulation of SALL4. DAC pretreatment sensitized SALL4-negative cancer cells to entinostat, which negatively affected SALL4 expression through a microRNA, miRNA-205, both in culture and in vivo. Moreover, SALL4 was essential for the efficiency of sequential treatment of DAC and entinostat. Overall, this proof-of-concept study provides a framework whereby the targeting pathways such as SALL4-centered therapy can be expanded, sensitizing cancer cells to treatment by transient target induction and engineering a dependency. SIGNIFICANCE: These findings provide a therapeutic approach for patients harboring no suitable target by induction of a SALL4-mediated vulnerability.