Low caveolin-1 levels and symptomatic intracranial haemorrhage risk in large-vessel occlusive stroke patients after endovascular thrombectomy.

BACKGROUND AND PURPOSE: Caveolin-1 (Cav-1) is reported to mediate blood-brain barrier integrity after ischaemic stroke. Our purpose was to assess the role of circulating Cav-1 levels in predicting symptomatic intracranial haemorrhage (sICH) amongst ischaemic stroke patients after endovascular thrombectomy (EVT). METHODS: Patients with large-vessel occlusive stroke after EVT from two stroke centres were prospectively included. Serum Cav-1 level was tested after admission. sICH was diagnosed according to the Heidelberg Bleeding Classification. RESULTS: Of 325 patients (mean age 68.6 years; 207 men) included, 47 (14.5%) were diagnosed with sICH. Compared with patients without sICH, those with sICH had a lower concentration of Cav-1. After adjusting for potential confounders, multivariate regression analysis demonstrated that the increased Cav-1 level was associated with a lower sICH risk (odds ratio 0.055; 95% confidence interval 0.005-0.669; p = 0.038). Similar results were obtained when Cav-1 levels were analysed as a categorical variable. Using a logistic regression model with restricted cubic splines, a linear and negative association of Cav-1 concentration was found with sICH risk (p = 0.001 for linearity). Furthermore, the performance of the conventional risk factors model in predicting sICH was substantially improved after addition of the Cav-1 levels (integrated discrimination index 2.7%, p = 0.002; net reclassification improvement 39.7%, p = 0.007). CONCLUSIONS: Our data demonstrate that decreased Cav-1 levels are related to sICH after EVT. Incorporation of Cav-1 into clinical decision-making may help to identify patients at a high risk of sICH and warrants further consideration.

Association between liver fibrosis and stroke recurrence in young patients with ischemic stroke.

BACKGROUND AND AIM: Stroke incidence rates are rising among young adults. Liver fibrosis has recently been recognized as a risk factor for cardiovascular events and stroke in the general population. It remains unclear whether liver fibrosis influences the prognosis of stroke. We aimed to evaluate the association between liver fibrosis and stroke recurrence in young stroke patients. METHODS AND RESULTS: Young adults with first-ever ischemic stroke were enrolled from a prospective stroke registry and were followed up for stroke recurrence. Liver fibrosis was evaluated by Fibrosis-4 (FIB-4) score and was stratified into three categories. Cox regression analysis was performed to assess the relationship between liver fibrosis and stroke recurrence. Over a median follow-up of 3.1 (1.7-4.6) years, 72 (11.6%) recurrent strokes occurred among 621 patients. According to the FIB-4 score, 73 (11.7%) patients had indeterminate fibrosis, while 11 (1.8%) had advanced fibrosis. Univariate Cox analysis revealed that patients with a high FIB-4 score were more likely to experience stroke recurrence than those with a low FIB-4 score (hazard ratio 3.748, 95% confidence interval 1.359-10.332, P = 0.011). After adjusting for potential confounders in the multivariate analysis, FIB-4 score remained an independent risk factor. CONCLUSIONS: Young stroke patients with advanced liver fibrosis were at a greater risk of stroke recurrence. Evaluating liver fibrosis may provide valuable information for stroke risk stratification, and the FIB-4 score could serve as a useful tool.

Real-world experience with Deutetrabenazine management in patients with Huntington's disease using video-based telemedicine.

BACKGROUND: Huntington's disease (HD) is a rare progressive neurological disorder, and telemedicine has the potential to improve the quality of care for patients with HD. Deutetrabenazine (DTBZ) can reduce chorea symptoms in HD; however, there is limited experience with this medication in Asian countries. METHODS: Retrospective and prospective studies were employed to explore the feasibility and reliability of a video-based telemedicine system for HD patient care. Reliability was demonstrated through consistency between selected-item scores (SIS) and total motor scores (TMS) and the agreement of scores obtained from hospital and home videos. Finally, a single-centre real-world DTBZ management study was conducted based on the telemedicine system to explore the efficacy of DTBZ in patients with HD. RESULTS: There were 77 patients included in the retrospective study, and a strong correlation was found between SIS and TMS (r = 0.911, P < 0.0001), indicating good representativeness. There were 32 patients enrolled in the prospective study. The reliability was further confirmed, indicated by correlations between SIS and TMS (r = 0.964, P < 0.0001) and consistency of SIS derived from the in-person and virtual visits (r = 0.969, P < 0.0001). There were 17 patients included in the DTBZ study with a mean 1.41 (95% confidence interval, 0.37-2.46) improvement in chorea score and reported treatment success. CONCLUSIONS: A video-based telemedicine system is a feasible and reliable option for HD patient care. It may also be used for drug management as a supplementary tool for clinical visits.

Ametoctradin resistance risk and its resistance-related point mutation in PsCytb of Phytophthora sojae confirmed using ectopic overexpression.

Ametoctradin is mainly used to treat plant oomycetes diseases, but the mechanism and resistance risk of ametoctradin in Phytophthora sojae remain unknown. This study determined the ametoctradin sensitivity of 106 P. sojae isolates and found that the frequency distribution of the median effective concentration (EC50) of ametoctradin was unimodal with a mean value of 0.1743 ± 0.0901 µg/mL. Furthermore, ametoctradin-resistant mutants had a substantially lower fitness index compared with that of wild-type isolates. Although ametoctradin did not show cross-resistance to other fungicides, negative cross-resistance to amisulbrom was found. In comparison to sensitive isolates, the control efficacy of ametoctradin to resistant mutants was lower, implying a low to moderate ametoctradin resistance risk in P. sojae. All ametoctradin-resistant mutants contained a S33L point mutation in PsCytb. A system with overexpression of PsCytb in the nucleus was established. When we ectopically overexpressed S33L-harboring PsCytb, P. sojae developed ametoctradin resistance. We hypothesized that the observed negative resistance between ametoctradin and amisulbrom could be attributed to conformational changes in the binding cavity of PsCytb at residues 33 and 220.

Two point mutations N771S and K847N in the VHA-a of Phytophthora litchii confer resistance to fluopimomide.

The phytopathogenic oomycete Phytophthora litchii is the culprit behind the devastating disease known as "litchi downy blight", which causes large losses in litchi production. Although fluopimomide exhibits strong inhibitory efficacy against P. litchii, the exact mechanism of resistance is still unknown. The sensitivity of 137 P. litchii isolates to fluopimomide was assessed, and it was discovered that the median effective concentration (EC50) of the fungicide had a unimodal frequency distribution with a mean value of 0.763 ± 0.922 µg/mL. Comparing the resistant mutants to the equivalent parental isolates, the resistance mutants' survival fitness was much lower. While there was no cross-resistance between fluopimomide and other oomycete inhibitors, there is a notable positive cross-resistance between fluopimomide and fluopicolide. According to the thorough investigation, P. litchii had a moderate chance of developing fluopimomide resistance. The point mutations N771S and K847N in the VHA-a of P. litchii (PlVHA-a) were present in the fluopimomide-resistant mutants, and the two point mutations in PlVHA-a conferring fluopimomide resistance were verified by site-directed mutagenesis in the sensitive P. capsici isolate BYA5 and molecular docking.

Hydrogen-Induced Formation of Surface Acid Sites on Pt/Al(PO3)3 Enables Remarkably Efficient Hydrogenolysis of C-O Bonds in Alcohols and Ethers.

The hydrogenolysis of oxygenates such as alcohols and ethers is central to the biomass valorization and also a valuable transformation in organic synthesis. However, a mild and efficient catalyst system for the hydrogenolysis of a large variety of alcohols and ethers with various functional groups is still underdeveloped. Here, we report an aluminum metaphosphate-supported Pt nanoparticles (Pt/Al(PO3)3) for the hydrogenolysis of a wide variety of primary, secondary, and tertiary alkyl and benzylic alcohols, and dialkyl, aryl alkyl, and diaryl ethers, including biomass-derived furanic compounds, under mild conditions (0.1-1 atm of H2, as low as 70 °C). Mechanistic studies suggested that H2 induces formation of the surface Brønsted acid sites via its cleavage by supported Pt nanoparticles. Accordingly, the high efficiency and the wide applicability of the catalyst system are attributed to the activation and cleavage of C-O bonds by the hydrogen-induced Brønsted acid sites with the assistance of Lewis acidic Al sites on the catalyst surface. The high efficiency of the catalyst implies its potential application in energy-efficient biomass valorization or fine chemical synthesis.

Multifunctional WO3-ZrO2-Supported Platinum Catalyst for Remarkably Efficient Hydrogenolysis of Esters to Alkanes.

The hydrogenolysis of esters to alkanes is a key protocol for the synthesis of high-quality hydrocarbon fuels from renewable plant oils or fats. However, performing this process under mild energy-efficient conditions is challenging. Herein, we report a robust tungsten- and zirconium-oxide-supported platinum catalyst (Pt/WO3-ZrO2) for the hydrogenolysis of esters to alkanes at low temperatures (as low as 70 °C) and under ambient pressure (1 atm) of H2. For example, tristearin undergoes a complete conversion at 130 °C with more than 95% selectivity for the corresponding alkanes without carbon loss. In addition, the heterogeneous nature of the catalyst system reported herein permits multiple reuse of the catalyst without any significant loss of its high activity and selectivity. Mechanistic studies suggest that the multifunctional nature (acid and redox properties) of the WO3-ZrO2 support plays an important role in the high activity of the catalyst.

Matrix metalloproteinase-2 delivery to extracellular vesicles produced by HPV-positive cervical cancer cells enhances metastasis via the Akt pathway.

Here, we aimed to analyze the effects of matrix metalloproteinase-2 (MMP-2) delivery to extracellular vesicles (EVs) secreted by human papillomavirus (HPV)-associated cervical cancer cells on human umbilical vein endothelial cell (HUVEC) angiogenesis. First, MMP-2 expression was compared among SiHa (HPV16), HeLa (HPV18), and C-33A (negative) cells. Then, EVs were isolated from these cells, and MMP-2 expression in the EVs was compared. SiHa and HeLa cells were transfected with MMP-2 or control siRNA. HUVECs were treated with EVs isolating from transfected cells. Migration and angiogenesis of HUVECs were measured, and p-Akt protein expression in HUVECs was detected. An Akt inhibitor or activator was used to analyze the effect of MMP-2 delivery to EVs on the migration of HUVECs. The SiHa-induced xenograft tumors were treated with 2 µg of EVs every 3 d for a total of 27 d. Tumor growth, and the expression levels of p-Akt, MMP-2, and vascular endothelial growth factor (VEGF) were observed in the tumors. The results showed that MMP-2 expression was higher in SiHa- and HeLa-derived EVs than that in the C-33A-derived EVs. Interference with MMP-2 suppressed the invasion of SiHa and HeLa cells. The migration and angiogenesis of HUVECs were enhanced by MMP-2 delivery to EVs secreted by SiHa and HeLa cells through regulation of the Akt pathway. The growth of xenograft tumors was accelerated by EVs secreted by SiHa cell with differential MMP-2 expression. Our results indicate the delivered MMP-2 in EVs acts as a messenger between HPV-associated cancer cells and HUVECs.

LncRNA SLC7A11-AS1 promotes the progression of hepatocellular carcinoma by mediating KLF9 ubiquitination.

Hepatocellular carcinoma (HCC) is a malignant tumor, which seriously threatens the life of patients. LncRNA SLC7A11-AS1 was reported to be abnormally expressed in HCC. Here, the functions and relative molecular regulatory mechanism of SLC7A11-AS1 in HCC were investigated. Nude mice and HCC cells were used as the experimental subjects. Knockdown or overexpression of exogenous genes was conducted in HCC cells. RT-qPCR, IHC, and western blot were employed to evaluate the abundance of genes and proteins. The malignant behaviors were evaluated using CCK-8, clone formation, wound-healing, and Transwell. The locations of SLC7A11-AS1 and KLF9 in cells were determined by FISH and IF assays. The total m6A level was evaluated by dot-blot assay. m6A modification of SLC7A11-AS1 was detected using RNA MeRIP. The interactions among molecules were validated by RIP, ChIP, dual luciferase reporter assay, and co-IP. SLC7A11-AS1 was elevated apparently in HCC cells and HCC tissues from mice. SLC7A11-AS1 silencing could suppress HCC progression, which was validated in in vivo and in vitro experiments. Furthermore, METTL3 mediated m6A modification of SLC7A11-AS1 to elevate its expression. In addition, SLC7A11-AS1 downregulated KLF9 expression by affecting STUB1-mediated ubiquitination degradation and KLF9 enhanced PHLPP2 expression to inactivate the AKT pathway. Eventually, rescue experiments revealed that KLF9 knockdown abolished SLC7A11-AS1 silencing-mediated suppression of HCC progression in vivo and in vitro. Our results unveiled that m6A-modified SLC7A11-AS1 promoted HCC progression by regulating the STUB1/KLF9/PHLPP2/AKT axis, indicating that targeting SLC7A11-AS1 might alleviate HCC progression.

Haloboration of o-Alkynyl Phenols Generates Halogenated Bicyclic-Boronates.

Benzoxaborinines are intermediates en-route to bicyclic boronates that are important active pharmaceutical ingredients (APIs). Herein, the haloboration of o-alkynyl-phenols using BX3 (X=Cl or Br) is disclosed as a route to form C4-X-benzoxaborinines with good functional group tolerance. Computational studies indicated that there are two similar in barrier mechanisms: (i) double alkyne haloboration followed by retro-haloboration; (ii) concerted trans-haloboration involving an exogenous chloride source. The C4-halide in these benzoxaborinines is useful, with a one-pot haloboration-Negishi cross coupling protocol effective to form benzoxaborinines with an alkyl or an aryl at C4. Therefore this method is a useful addition to the toolbox for synthesising bicyclic-boronates that are attracting increasing attention as APIs.

Resonant energy transfer between rare earth atomic layers in nanolaminate films.

Förster resonant energy transfer between atoms separated at a distance of a few nanometers has strong relevance to different properties of matter. In this work, the resonant energy transfer rate is derived from the electric potential in a system with one dipole interacting with a separated 2D plane of dipoles. It shows an R-2 (R: distance between dipole and 2D plane of dipoles) dependency on the distance of dipole layers, which is different from previous theoretical evaluations with an R-4 dependency. The electroluminescence (EL) properties are studied in different rare earth (Re: Tm, Tb, Ho, Yb, Er) distributed single atomic layer doped Al2O3 nanolaminates prepared by atomic layer deposition, in which the distance between single atomic layers of Re3+ is modulated at the atomic scale. Our theoretical results are consistent with the changes of EL intensity and decay time with the distance between the single atomic rare earth doping layers. This result is crucial for increasing the accuracy in biosensing and design of photonic materials.

Non-alcoholic fatty liver disease and stroke: A Mendelian randomization study.

BACKGROUND: The association between non-alcoholic fatty liver disease (NAFLD) and the risk of stroke is heterogeneous. Therefore, we aimed to examine any potential causal relationship between these two traits through Mendelian randomization. METHODS: The genetic instruments associated with NAFLD were selected from a large genome-wide association study in individuals of European ancestry (1483 cases and 17,781 controls, replicated in 559 cases and 945 controls). The genetic associations for stroke (40,585 cases and 406,111 controls) and ischemic stroke (34,217 cases and 406,111 controls) were selected from the MEGASTROKE consortium of European ancestry participants. The causal effects on ischemic stroke subtypes, including large artery atherosclerosis (LAA) (4373 cases and 146,392 controls), small vessel occlusion (SVO) (5386 cases and 192,662 controls), and cardioembolic stroke (7193 cases and 204,570 controls), were also analyzed. The inverse variant weighted method was performed to obtain the casual estimates. Heterogeneity and pleiotropy of individual single nucleotide polymorphisms were also tested for the robustness of the results. RESULTS: NAFLD was not associated with stroke (odds ratio [OR] 1.015; 95% confidence interval [CI] 0.996-1.034; p = 0.121) and ischemic stroke (OR 1.017; 95% CI 0.997-1.037; p = 0.092). Regarding ischemic stroke subtypes, there were positive causal inferences on LAA (OR 1.065; 95% CI 1.004-1.129; p = 0.037) and SVO (OR 1.058; 95% CI 1.003-1.116; p = 0.037), while it was not significant for cardioembolic stroke (OR 1.026; 95% CI 0.983-1.071; p = 0.243). CONCLUSION: This study suggests that the potential causal effect of NAFLD on ischemic stroke may be confined to the LAA and SVO subtypes.

3,4-Bisthiolated Pyrroles: Concise Construction and Their Electronic Properties.

3,4-Bisthiolated pyrroles constitute key cores in pyrrole-based semiconductors, and their electronic properties could be improved by the bisthio groups via the S-effect. Herein, a convenient method for the synthesis of 3,4-bisthiolated pyrroles has been developed through the AlCl3-catalyzed thiolation/cyclization of homopropargylic azides, and cyclic voltammetry and DFT calculations indicated that the desired 3,4-bisthiolated pyrroles had higher HOMO orbital energies and lower band gaps than the parent unsubstituted 2,5-diphenylpyrrole.

Dipeptidyl peptidase-8 induces sorafenib resistance via binding with c-Rel to mediate NF-κB signaling in hepatocellular carcinoma.

Sorafenib is the important first-standard drug for patients with advanced hepatocellular carcinoma (HCC). A major obstacle to successful treatment is sorafenib resistance. However, the mechanism of sorafenib resistance is unclear. The present study aimed to determine the involvement of dipeptidyl peptidase-8 (DPP8) in sorafenib resistance. DPP8 expression was detected using quantitative real-time PCR (qPCR) and western blot analysis. The effect of DPP8 on sorafenib resistance was examined using terminal deoxynulceotidyl transferase nick-end-labeling (TUNEL), colony formation, flow cytometry, luciferase reporter, immunofluorescence, and immunoprecipitation (IP) assays. We found that DPP8 mRNA and protein levels were dramatically upregulated in HCC. Gene set enrichment analysis (GSEA) illustrated that DPP8 might be involved in apoptosis regulation. Downregulation of DPP8 substantially promoted the sensitivity of HCC cells to sorafenib. Further analysis showed that DPP8 might regulate nuclear factor kappa B (NF-κB) signaling, which was confirmed using a luciferase reporter assay. Downregulation of DPP8 decreased the expression levels of downstream genes of the NF-κB pathway. IP showed that DPP8 can interact with NF-κB subunit c-Rel, an important protein of NF-κB signaling. Finally, a drug combination of sorafenib and Val-boroPro induced higher mortality of HCC cells than sorafenib alone in DPP8-upregulated cells. Our findings indicated that using the inhibitor Val-boroPro might be a promising method to enhance sorafenib sensitivity in advanced HCC.

Multi-marker approach using C-reactive protein, procalcitonin, neutrophil CD64 index for the prognosis of sepsis in intensive care unit: a retrospective cohort study.

BACKGROUND: We aimed to explore the prognostic utilities of C-reactive protein (CRP), procalcitonin (PCT), neutrophil CD64 (nCD64) index, in combination or alone, in septic patients. METHODS: We retrospectively included 349 septic patients (based on Sepsis 3.0 definition). The primary outcome was 28-day all-cause mortality. Cox regression model, receiver-operating characteristic (ROC) curve, reclassification analysis, Kaplan-Meier survival curves were performed to evaluate the predictive efficacy of the above parameters. RESULTS: CRP, nCD64 index were independent predictors of 28-day mortality for sepsis in the Cox regression model [CRP, HR 1.004 (95% CI 1.002-1.006), P < 0.001; nCD64 index, HR 1.263 (95% CI 1.187-1.345, P < 0.001]. Area under the ROC curve (AUC) of CRP, PCT, nCD64 index, nCD64 index plus PCT, nCD64 index plus CRP, were 0.798 (95% CI 0.752-0.839), 0.833 (95% CI 0.790-0.871), 0.906 (95% CI 0.870-0.935), 0.910 (95% CI 0.875-0.938), 0.916 (95% CI 0.881-0.943), respectively. nCD64 plus CRP performed best in prediction, discrimination, and reclassification of the 28-day mortality risk in sepsis. The risk of 28-day mortality increased stepwise as the number of data exceeding optimal cut-off values increased. CONCLUSIONS: nCD64 index combined with CRP was superior to CRP, PCT, nCD64 index and nCD64 index plus PCT in predicting 28-day mortality in sepsis. Multi-marker approach could improve the predictive accuracy and be beneficial for septic patients.

Nb-doped La0.6Sr0.4FeO3-δ as an electrolyte for intermediate-temperature solid oxide fuel cells.

It is one of the effective strategies to develop intermediate-temperature solid oxide fuel cells (IT-SOFCs) by looking for alternative electrolyte materials that can maintain or even improve current cell efficiencies while reducing operating temperature. In this study, by rationally introducing pentavalent Nb on the B-site of La0.6Sr0.4FeO3-δ (LSFO), a serial of novel perovskite La0.6Sr0.4Fe1-xNbxO3-δ (LSFNbx, x = 0.1, 0.2) with mixed electron-ion conduction is successfully prepared. The electrochemical mechanism and performance of the symmetrical IT-SOFCs with a single LSFNbx perovskite oxide as electrolyte are investigated. With the Nb doping, the structure stability of the LSFO is improved and the electronic conductivity decreases. La0.6Sr0.4Fe0.8Nb0.2O3-δ (LSFNb20) is the most promising electrolyte of the three candidates as it has the best performance (735 mW cm-2 at 550 °C in a dry H2/Air atmosphere) and no short-circuiting problem. The applied voltage-response current curves demonstrate that the interface between the Ni-Ni0.8Co0.15Al0.05LiO2-δ anode and LSFNb20 electrolyte can block electron conduction more efficiently and has a better promoting effect on protons, which is fundamentally due to the band energy alignment of the interface heterojunction. Our work highlights that LSFNb20 is a high-performance perovskite alternative to monolayer electrolytes.

Two Directing Groups Used for Metal Catalysed Meta-C-H Functionalisation Only Effect Ortho Electrophilic C-H Borylation.

Two templates used in meta-directed C-H functionalisation under metal catalysis do not direct meta-C-H borylation under electrophilic borylation conditions. Using BCl3 only Lewis adduct formation with Lewis basic sites in the template is observed. While combining BBr3 and the template containing an amide linker only led to amide directed ortho C-H borylation, with no pyridyl directed meta borylation. The amide directed borylation is selective for the ortho borylation of the aniline derived unit in the template, with no ortho borylation of the phenylacetyl ring - which would also form a six membered boracycle - observed. In the absence of other aromatics amide directed ortho borylation on to phenylacetyl rings can be achieved. The absence of meta-borylation using two templates indicates a higher barrier to pyridyl directed meta borylation relative to amide directed ortho borylation and suggests that bespoke templates for enabling meta-directed electrophilic borylation may be required.

Monitoring and characterization of prochloraz resistance in Fusarium fujikuroi in China.

Rice bakanae disease, caused by Fusarium fujikuroi, is a destructive seed-borne disease throughout the world. Prochloraz, a DMI (C-14α-demethylase inhibitor) fungicide, has been registered in China for >20 years. Prochloraz resistance in F. fujikuroi was severe in China with resistance frequencies of 34.56%, 45.33%, and 48.45% from 2019 to 2021. The fitness of prochloraz-resistant population was lower than that of sensitive population, with an average CFI of 2.86 × 106 and 4.56 × 106, respectively. No cross-resistance was detected between prochloraz and tebuconazole or hexaconazole, and the prochloraz-resistant isolates were still sensitive to fludioxonil, phenamacril, and pydiflumetofen. S312T mutation in Ffcyp51b or overexpression of Ffcyp51a and Ffcyp51b was detected in the highly resistant isolates. AS-PCR primers were designed to detect the prochloraz-resistant isolates with S312T mutation in the field. Resistant isolates carrying S312T mutation were the dominant group in prochloraz-resistant population with frequencies of 43.26%, 23.59%, and 71.20% from 2019 to 2021, which indicated that more attention should be paid to this genotype when monitoring and managing the prochloraz resistance in F. fujikuroi.

Borylation Directed Borylation of Indoles Using Pyrazabole Electrophiles: A One-Pot Route to C7-Borylated-Indolines.

Pyrazabole (1) is a readily accessible diboron compound that can be transformed into ditopic electrophiles. In 1 (and derivatives), the B⋅⋅⋅B separation is ca. 3 Å, appropriate for one boron centre bonding to N and one to the C7 of indoles and indolines. This suitable B⋅⋅⋅B separation enables double E-H (E=N/C) functionalisation of indoles and indolines. Specifically, the activation of 1 with HNTf2 generates an electrophile that transforms N-H indoles and indolines into N/C7-diborylated indolines, with N-H borylation directing subsequent C7-H borylation. Indole reduction to indoline occurs before C-H borylation and our studies indicate this proceeds via hydroboration-C3-protodeboronation to produce an intermediate that then undergoes C7 borylation. The borylated products can be converted in situ into C7-BPin-N-H-indolines. Overall, this represents a transient directed C-H borylation to form useful C7-BPin-indolines.

Amplification of DDR2 mediates sorafenib resistance through NF-κB/c-Rel signaling in hepatocellular carcinoma.

Sorafenib was the first systemic therapy approved by the Food and Drug Administration to treat advanced hepatocellular carcinoma (HCC). However, sorafenib therapy is frequently accompanied by drug resistance. We aimed to explore the mechanisms of sorafenib resistance and provide feasible solutions to increase the response to sorafenib in patients with advanced HCC. The expression profile of discoidin domain receptor 2 (DDR2) in HCC tissues and cells was detected using quantitative real-time PCR (qPCR) and western blotting assays. The effects of DDR2 on sorafenib resistance were examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation, TdT-mediated dUTP nick end labeling, and flow cytometry assays. The effect of DDR2 on the nuclear factor kappa B (NF-κB) signaling pathway was evaluated by luciferase reporter, immunofluorescence, qPCR and flow cytometry assays. We demonstrated that DDR2 expression was dramatically upregulated in sorafenib-resistant HCC tissues relative to sensitive tissues. Downregulation of DDR2 sensitized HCC cell lines to sorafenib cytotoxicity. Further analysis showed that DDR2 could increase the nuclear location of REL proto-oncogene, a NF-κB subunit, to mediate NF-κB signaling. Blocking NF-κB signaling using the NF-κB signaling inhibitor, bardoxolone methyl, increased the response of HCC cells to sorafenib. Further analysis showed that DNA amplification of DDR2 is an important mechanism leading to DDR2 overexpression in HCC. Our results demonstrated that DDR2 is a potential therapeutic target in patients with HCC, and targeting DDR2 represents a promising approach to increase sorafenib sensitivity in patients with HCC.