Design, synthesis and biological evaluation of aloperine derivatives as potential anticancer agents.

Modifications at different positions on the aloperine molecule were performed to improve its anticancer activity and develop anticancer drugs. The in vitro anticancer activities of 44 synthesized compounds were evaluated. The effect of modification positions on anticancer activity was discussed and a structure-activity relationship analysis was established. A novel series of compounds with modifications at the N12 position showed much higher cytotoxicity than aloperine. Among them, compound 22 displayed promising in vitro anticancer activity against PC9 cells with a median inhibitory concentration (IC50) of 1.43 µM. The mechanism studies indicated that compound 22 induced cell apoptosis and cell cycle arrest in PC9 cells. These results demonstrate the potential of aloperine thiourea derivatives in anticancer activity.

Catalytic [4+2]- and [4+4]-cycloaddition using furan-fused cyclobutanone as a privileged C4 synthon.

Cycloaddition reactions play a pivotal role in synthetic chemistry for the direct assembly of cyclic architectures. However, hurdles remain for extending the C4 synthon to construct diverse heterocycles via programmable [4+n]-cycloaddition. Here we report an atom-economic and modular intermolecular cycloaddition using furan-fused cyclobutanones (FCBs) as a versatile C4 synthon. In contrast to the well-documented cycloaddition of benzocyclobutenones, this is a complementary version using FCB as a C4 reagent. It involves a C-C bond activation and cycloaddition sequence, including a Rh-catalyzed enantioselective [4 + 2]-cycloaddition with imines and an Au-catalyzed diastereoselective [4 + 4]-cycloaddition with anthranils. The obtained furan-fused lactams, which are pivotal motifs that present in many natural products, bioactive molecules, and materials, are inaccessible or difficult to prepare by other methods. Preliminary antitumor activity study indicates that 6e and 6 f exhibit high anticancer potency against colon cancer cells (HCT-116, IC50 = 0.50 ± 0.05 µM) and esophageal squamous cell carcinoma cells (KYSE-520, IC50 = 0.89 ± 0.13 µM), respectively.

Dietary ellagic acid therapy for CNS autoimmunity: Targeting on Alloprevotella rava and propionate metabolism.

BACKGROUND: Mediterranean diet rich in polyphenolic compounds holds great promise to prevent and alleviate multiple sclerosis (MS), a central nervous system autoimmune disease associated with gut microbiome dysbiosis. Health-promoting effects of natural polyphenols with low bioavailability could be attributed to gut microbiota reconstruction. However, its underlying mechanism of action remains elusive, resulting in rare therapies have proposed for polyphenol-targeted modulation of gut microbiota for the treatment of MS. RESULTS: We found that oral ellagic acid (EA), a natural polyphenol rich in the Mediterranean diet, effectively halted the progression of experimental autoimmune encephalomyelitis (EAE), the animal model of MS, via regulating a microbiota-metabolites-immunity axis. EA remodeled the gut microbiome composition and particularly increased the relative abundances of short-chain fatty acids -producing bacteria like Alloprevotella. Propionate (C3) was most significantly up-regulated by EA, and integrative modeling revealed a strong negative correlation between Alloprevotella or C3 and the pathological symptoms of EAE. Gut microbiota depletion negated the alleviating effects of EA on EAE, whereas oral administration of Alloprevotella rava mimicked the beneficial effects of EA on EAE. Moreover, EA directly promoted Alloprevotella rava (DSM 22548) growth and C3 production in vitro. The cell-free supernatants of Alloprevotella rava co-culture with EA suppressed Th17 differentiation by modulating acetylation in cell models. C3 can alleviate EAE development, and the mechanism may be through inhibiting HDAC activity and up-regulating acetylation thereby reducing inflammatory cytokines secreted by pathogenic Th17 cells. CONCLUSIONS: Our study identifies EA as a novel and potentially effective prebiotic for improving MS and other autoimmune diseases via the microbiota-metabolites-immunity axis. Video Abstract.

Genome-Wide Association Study Identifies IFIH1 and HLA-DQB1*05:02 Loci Associated With Anti-NMDAR Encephalitis.

BACKGROUND AND OBJECTIVES: Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is a rare autoimmune neurologic disorder, the genetic etiology of which remains poorly understood. Our study aims to investigate the genetic basis of this disease in the Chinese Han population. METHODS: We performed a genome-wide association study and fine-mapping study within the major histocompatibility complex (MHC) region of 413 Chinese patients with anti-NMDAR encephalitis recruited from 6 large tertiary hospitals and 7,127 healthy controls. RESULTS: Our genome-wide association analysis identified a strong association at the IFIH1 locus on chromosome 2q24.2 (rs3747517, p = 1.06 × 10-8, OR = 1.55, 95% CI, 1.34-1.80), outside of the human leukocyte antigen (HLA) region. Furthermore, through a fine-mapping study of the MHC region, we discovered associations for 3 specific HLA class I and II alleles. Notably, HLA-DQB1*05:02 (p = 1.43 × 10-12; OR, 2.10; 95% CI 1.70-2.59) demonstrates the strongest association among classical HLA alleles, closely followed by HLA-A*11:01 (p = 4.36 × 10-7; OR, 1.52; 95% CI 1.29-1.79) and HLA-A*02:07 (p = 1.28 × 10-8; OR, 1.87; 95% CI 1.50-2.31). In addition, we uncovered 2 main HLA amino acid variation associated with anti-NMDAR encephalitis including HLA-DQß1-126H (p = 1.43 × 10-12; OR, 2.10; 95% CI 1.70-2.59), exhibiting a predisposing effect, and HLA-B-97R (p = 3.40 × 10-8; OR, 0.63; 95% CI 0.53-0.74), conferring a protective effect. Computational docking analysis suggested a close relationship between the NR1 subunit of NMDAR and DQB1*05:02. DISCUSSION: Our findings indicate that genetic variation in IFIH1, involved in the type I interferon signaling pathway and innate immunity, along with variations in the HLA class I and class II genes, has substantial implications for the susceptibility to anti-NMDAR encephalitis in the Chinese Han population.

A novel HDAC6 inhibitor attenuate APAP-induced liver injury by regulating MDH1-mediated oxidative stress.

Glutathione (GSH) depletion, mitochondrial damage, and oxidative stress have been implicated in the pathogenesis of acetaminophen (APAP) hepatotoxicity. Here, we demonstrated that the expression of histone deacetylase 6 (HDAC6) is highly elevated, whereas malate dehydrogenase 1 (MDH1) is downregulated in liver tissues and AML-12 cells induced by APAP. The therapeutic benefits of LT-630, a novel HDAC6 inhibitor on APAP-induced liver injury, were also substantiated. On this basis, we demonstrated that LT-630 improved the protein expression and acetylation level of MDH1. Furthermore, after overexpression of MDH1, an upregulated NADPH/NADP+ ratio and GSH level and decreased cell apoptosis were observed in APAP-stimulated AML-12 cells. Importantly, MDH1 siRNA clearly reversed the protection of LT-630 on APAP-stimulated AML-12 cells. In conclusion, LT-630 could ameliorate liver injury by modulating MDH1-mediated oxidative stress induced by APAP.

CHL1 inhibits cell proliferation, migration and invasion by regulating the NF­κB signaling pathway in colorectal cancer.

Cell adhesion molecule close homolog of L1 (CHL1) is implicated in tumorigenesis of various malignancies. However, its role and underlying molecular mechanisms in colorectal cancer (CRC) remain unclear. The present study aimed to evaluate the specific biological functions and mechanisms of CHL1, in order to provide a theoretical basis for the use of CHL1 as a biological target in CRC. CHL1 expression was originally determined in CRC cell lines. Subsequently, CHL1 overexpression was induced by plasmid transfection in HT29 and SW480 cells, and cell proliferation, migration and invasion were evaluated using the Cell Counting Kit-8, clone formation, organoids formation and Transwell assays. Immunofluorescence and western blotting were performed to assess the protein expression of E-cadherin or N-cadherin. Differentially expressed genes (DEGs) were further evaluated using RNA-sequencing (RNA-seq) in HT29 and SW480 cells following CHL1 overexpression and functional enrichment analysis. Western blotting was performed to validate the expression of proteins related to the nuclear factor κB (NF-κB) signaling pathway. The TNMplot online database revealed the significant downregulation of CHL1 in CRC tissues. The results indicated that exogenous CHL1 overexpression significantly inhibited the proliferative, organoid-forming, migratory and invasive abilities of HT29 and SW480 cells, and increased E-cadherin protein expression. Additionally, CHL1 overexpression reduced xenograft tumor growth in vivo. RNA-seq and functional analysis revealed that DEGs in CHL1 overexpressing cells were mainly enriched in the NF-κB signaling pathway. The expression of p-p65 and p-p65/p65 ratio were significantly reduced in HT29 and SW480 cells, following CHL1 overexpression. Additionally, the inhibitory effects of CHL1 overexpression on CRC cell proliferation, organoid formation, migration and invasion were partially counteracted following the overexpression of p65 expression. Overall, the present study demonstrates that CHL1 inhibits CRC cell growth, migration and invasion through the inactivation of the NF-κB signaling pathway.

Visible-Light-Driven Iron-Catalyzed Intermolecular Benzylic C(sp3)-H Amination with 1,2,3,4-Tetrazoles.

A visible-light-driven iron-catalyzed C(sp3)-H amination of diphenylmethane derivatives with 1,2,3,4-tetrazoles under mild conditions has been developed. The reaction proceeds with photosensitizer-free conditions and features satisfactory to good yields. Mechanistic studies revealed that the reaction proceeded via an iron-nitrene intermediate, and H atom abstraction was the rate-determining step. Computational studies showed that the denitrogenation of 1,2,3,4-tetrazole depends on the conversion of the sextet ground state of 1,2,3,4-tetrazole-bounding iron species to the quartet spin state under visible-light irradiation.

Visible-Light-Driven Iron-Catalyzed Decarboxylative C-N Coupling Reaction of Alkyl Carboxylic Acids with NaNO2.

An efficient visible-light-driven iron-catalyzed decarboxylative C-N coupling reaction of alkyl carboxylic acids with NaNO2 under mild conditions was developed. The reaction proceeds under photosensitizer-free conditions and features good to excellent yields, broad functional group tolerance, and an easy operation procedure. Preliminary mechanistic investigations showed that visible-light-driven iron catalysis not only achieved oxidative decarboxylation of alkyl carboxylic acids to alkyl radicals but also promoted the reduction of NO2- to NO, thus leading to the C-N radical coupling reaction.

Visible-light-induced iron-catalyzed reduction of nitroarenes to anilines.

An efficient visible-light-induced iron-catalyzed reduction of nitroarenes to anilines by using N-ethylmorpholine (NEM) as a reductant under mild conditions has been developed. The reaction proceeds with photosensitizer-free conditions and features good to excellent yields and broad functional group tolerance. Preliminary mechanistic investigations showed that this reaction was conducted via ligand-to-metal (NEM to Fe3+) charge transfer and nitro triplet biradical-induced hydrogen atom transfer processes.

Modular access to alkylgermanes via reductive germylative alkylation of activated olefins under nickel catalysis.

Carbon-introducing difunctionalization of C-C double bonds enabled by transition-metal catalysis is one of most straightforward and efficient strategies to construct C-C and C-X bonds concurrently from readily available feedstocks towards structurally diverse molecules in one step; however, analogous difunctionalization for introducing germanium group and other functionalities remains elusive. Herein, we describe a nickel-catalyzed germylative alkylation of activated olefins with easily accessible primary, secondary and tertiary alkyl bromides and chlorogermanes as the electrophiles to form C-Ge and C-Calkyl bonds simultaneously. This method provides a modular and facile approach for the synthesis of a broad range of alkylgermanes with good functional group compatibility, and can be further applied to the late-stage modification of natural products and pharmaceuticals, as well as ligation of drug fragments. More importantly, this platform enables the expedient synthesis of germanium substituted ospemifene-Ge-OH, which shows improved properties compared to ospemifene in the treatment of breast cancer cells, demonstrating high potential of our protocol in drug development.

Mass Spectrometry Detects Sphingolipid Metabolites for Discovery of New Strategy for Cancer Therapy from the Aspect of Programmed Cell Death.

Sphingolipids, a type of bioactive lipid, play crucial roles within cells, serving as integral components of membranes and exhibiting strong signaling properties that have potential therapeutic implications in anti-cancer treatments. However, due to the diverse group of lipids and intricate mechanisms, sphingolipids still face challenges in enhancing the efficacy of different therapy approaches. In recent decades, mass spectrometry has made significant advancements in uncovering sphingolipid biomarkers and elucidating their impact on cancer development, progression, and resistance. Primary sphingolipids, such as ceramide and sphingosine-1-phosphate, exhibit contrasting roles in regulating cancer cell death and survival. The evasion of cell death is a characteristic hallmark of cancer cells, leading to treatment failure and a poor prognosis. The escape initiates with long-established apoptosis and extends to other programmed cell death (PCD) forms when patients experience chemotherapy, radiotherapy, and/or immunotherapy. Gradually, supportive evidence has uncovered the fundamental molecular mechanisms underlying various forms of PCD leading to the development of innovative molecular, genetic, and pharmacological tools that specifically target sphingolipid signaling nodes. In this study, we provide a comprehensive overview of the sphingolipid biomarkers revealed through mass spectrometry in recent decades, as well as an in-depth analysis of the six main forms of PCD (apoptosis, autophagy, pyroptosis, necroptosis, ferroptosis, and cuproptosis) in aspects of tumorigenesis, metastasis, and tumor response to treatments. We review the corresponding small-molecule compounds associated with these processes and their potential implications in cancer therapy.

Blocking ATP-P1Rs axis attenuate alcohol-related liver fibrosis.

AIMS: The aim of this study was to explore the fibrogenic effects of ATP-P1Rs axis and ATP-P2Rs axis on alcohol-related liver fibrosis (ALF). MATERIALS AND METHODS: C57BL/6J CD73 knock out (KO) mice were used in our study. 8-12 weeks male mice were used as an ALF model in vivo. In conclusion, after one week of adaptive feeding, 5 % alcohol liquid diet was given for 8 weeks. High-concentration alcohol (31.5 %, 5 g/kg) was administered by gavage twice weekly, and 10 % CCl4 intraperitoneal injections (1 ml/kg) were administered twice weekly for the last two weeks. The mice in the control group were injected intraperitoneally with an equivalent volume of normal saline. Fasting for 9 h after the last injection, blood samples were collected, and related indicators were tested. In vitro, rat hepatic stellate cells (HSCs) were treated with 200 µM acetaldehyde to establish an alcoholic liver fibrosis for 48 h, then tested related indicators. KEY FINDINGS: We found that both adenosine receptors including adenosine A1, A2A, A2B, A3 receptors (A1R, A2AR, A2BR, A3R) and ATP receptors including P2X7, P2Y2 receptors (P2X7R, P2Y2R) were expressed increased in ALF. After CD73 was knocked out, we found that adenosine receptors expression decreased, ATP expression increased, and fibrosis degree decreased. SIGNIFICANCE: Based on the research, we discovered that adenosine plays a more important role in ALF. Therefore, blocking the ATP-P1Rs axis represented a potential treatment for ALF, and CD73 will become a potential therapeutic target.

Purification and identification of xanthine oxidase inhibitory peptides from enzymatic hydrolysate of α-lactalbumin and bovine colostrum casein.

The development of food-derived Xanthine Oxidase (XO) inhibitors is critical to the treatment of hyperuricemia and oxidative stress-related disease. Few studies report on milk protein hydrolysates' XO inhibitory activity, with the mechanism of their interaction remaining elusive. Here, different commercial enzymes were used to hydrolyze α-lactalbumin and bovine colostrum casein. The two proteins hydrolyzed by alkaline protease exhibited the most potent XO inhibitory activity (bovine casein: IC50 = 0.13 mg mL-1; α-lactalbumin: IC50 = 0.28 mg mL-1). Eight potential XO inhibitory peptides including VYPFPGPI, GPVRGPFPIIV, VYPFPGPIPN, VYPFPGPIHN, QLKRFSFRSFIWR, LVYPFPGPIHN, AVFPSIVGR, and GFININSLR (IC50 of 4.67-8.02 mM) were purified and identified from alkaline protease hydrolysates by using gel filtration, LC-MS/MS and PeptideRanker. The most important role of inhibiting activity of peptides is linked to hydrophobic interactions and hydrogen bonding based on the results of molecular docking and molecular dynamics simulation. The enzymatic hydrolysate of α-lactalbumin and bovine colostrum casein could be a competitive candidates for hyperuricemia-resisting functional food.

Gail model and fifth edition of ultrasound BI-RADS help predict axillary lymph node metastasis in breast cancer-A multicenter prospective study.

RATIONALE AND OBJECTIVES: We aim to assess the performance of the Gail model and the fifth edition of ultrasound BI-RADS (Breast Imaging Reporting and Data System) in breast cancer for predicting axillary lymph node metastasis (ALNM). MATERIALS AND METHODS: We prospectively studied 958 female patients with breast cancer between 2018 and 2019 from 35 hospitals in China. Based on B-mode, color Doppler, and elastography, radiologists classified the degree of suspicion based on the fifth edition of BI-RADS. Individual breast cancer risk was assessed with the Gail model. The association between the US BI-RADS category and the Gail model in terms of ALNM was analyzed. RESULTS: We found that US BI-RADS category was significantly and independently associated with ALNM (P < 0.001). The sensitivity, specificity, and accuracy of BI-RADS category 5 for predicting ALNM were 63.6%, 71.6%, and 68.6%, respectively. Combining the Gail model with the BI-RADS category showed a significantly higher sensitivity than using the BI-RADS category alone (67.8% vs. 63.6%, P < 0.001). The diagnostic accuracy of the BI-RADS category combined with the Gail model was better than that of the Gail model alone (area under the curve: 0.71 vs. 0.50, P < 0.001). CONCLUSION: Based on the conventional ultrasound and elastography, the fifth edition of ultrasound BI-RADS category could be used to predict the ALNM of breast cancer. ALNM was likely to occur in patients with BI-RADS category 5. The Gail model could improve the diagnostic sensitivity of the US BI-RADS category for predicting ALNM in breast cancer.

Synthesis of dihydrofuran-3-one and 9,10-phenanthrenequinone hybrid molecules and biological evaluation against colon cancer cells as selective Akt kinase inhibitors.

A series of dihydrofuran-3-one and 9,10-phenanthrenequinone hybrid compounds were synthetized through a one-pot gold-catalyzed oxidative cyclization and Aldol-type addition cascade reaction of homopropargylic alcohols with 9,10-phenanthrenequinone. The cytotoxicity of newly synthesized compounds was evaluated in CCK8 assay against different human cancer cells, showing significantly antiproliferative activity against tested tumor cell lines with a lowest IC50 value of 0.92 µM over HCT-116. Further investigation revealed that the treatment of HCT-116 cell line with the promising compound 4c induced cell death as a selective Akt inhibitor. In addition, controlled experiments and molecular docking study suggested that the significant antitumor activity might be attributed to the unique hybrid structure, which implied the promising potential of this dual heterocycle hybrid method in the discovery of novel bioactive molecules with structural diversity.

Gold-catalyzed carbocyclization and imidization of alkyne-tethered diazo compounds with nitrosoarenes for the synthesis of nitrones and naphthalene derivatives.

A gold-catalyzed carbocyclization/imidization cascade reaction has been developed,leading a facile access to the synthesis of functionalized nitrones in moderate to good yields under mild conditions. The reaction initiated by a catalytic 6-endo-dig diazo-yne carbocyclization to form the key endocyclic vinyl carbene from alkyne-tethered diazo compounds, followed by addition with nitrosoarenes that features an imidization process. Notably, these resulting nitrone products could be smoothly converted into different substituted naphthalenol analogues, such as 4-aminonaphthalen-1-ol, naphthalene-1,4-dione, and naphthalene-1,4-diol derivatives, in high yields. Moreover, the generated products exhibited potential tumor suppression activity in tested cancer celllines; compound 3c (HCT116 cells, IC50 = 7.41 µM; MCF-7 cells, IC50 = 14.28 µM) exhibits higher anticancer potency than other tested compounds.

"Rapid Formation, Acute Rupture" Course of Intracranial Aneurysm.

Intracranial aneurysm (IA) is a devastating cerebrovascular disease characterizing with a potential rupturing risk. In previous studies, the formation of IA was considered to be in a chronic manner, and the ruptured aneurysms might merely derived from the already formed unruptured IA. A 61-year-old male presented to the hospital complaining of a headache. The patient received neuroimage tests, including head computed tomography and digital substraction angiography, to examine the underlying cerebrovascular diseases. Interestingly, we found a newborn ruptured IA with 9-day intervals between 2 whole-cerebral digital subtraction angiography examinations. In summary, the case in our report provides a clue for the natural course that the IA is probably in a "rapid formation, acute rupture" manner.

CD73 aggravates alcohol-related liver fibrosis by promoting autophagy mediated activation of hepatic stellate cells through AMPK/AKT/mTOR signaling pathway.

CD73 is a membrane-bound glycoprotein that can dephosphorylate AMP to adenosine. Increasing evidence has shown that CD73 is involved in the occurrence and development of liver fibrosis. However, the potential mechanism by which CD73 affects the progression of alcohol-related liver fibrosis (ALF) remains unknown. This study aimed to examine the role and mechanism of CD73 in autophagy in HSC-T6 cells and its role in ALF in mice that treated with alcohol plus CCl4. We found that CD73 knockout reduced serum alanine aminotransferase and aspartate aminotransferase levels and decreased liver injury and collagen deposition. Furthermore, autophagy-related indicators were downregulated in the liver fibrosis tissues of CD73-/- (EtOH + CCl4) mice. In vitro, the expression of CD73 and autophagy increased in activated HSC-T6 cells. Autophagy inhibitor, 3-methyladenine, reduced autophagy and activation of acetaldehyde-induced HSC-T6 cells. When using CD73-siRNA, autophagy in HSC-T6 cells was found to be downregulated. However, the CD73 plasmid increased the activation and autophagy of hepatic stellate cells (HSCs). In addition, CD73 induced autophagy through the AMPK/AKT/mTOR pathway, which is characterized by an increase in the ratio of P-AMPKα/AMPKα and a decrease in the ratio of P-AKT/AKT and P-mTOR/mTOR. Our study found that CD73 promotes HSCs activation by regulating autophagy through the AMPK/AKT/mTOR signaling pathway.

ACR TI-RADS classification combined with number of nodules, halo features optimizes diagnosis and prediction of follicular thyroid cancer.

OBJECTIVES: To investigate the application value of The American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) category combined with other ultrasound features of nodules in distinguishing follicular thyroid carcinoma (FTC) from thyroid follicular adenoma (FTA). METHODS: We collected and retrospectively analyzed clinical and ultrasound data for 118 and 459 patients with FTCs and FTAs, respectively, at our hospital. Next, we used ACR TI-RADS classification combined with other ultrasound features of nodules to distinguish FTC from FTA. Multivariate Logistic regression was used to screen independent risk factors for FTC, which were subsequently used to construct a nomogram for predicting FTC. RESULTS: ACR TI-RADS categories 4 and 5, unilateral multiple nodules, and halo thickness≥2 mm were independent risk factors for FTC. ACR TI-RADS category combined with number of nodules, halo features of the nodule was a significantly better prediction model for FTC diagnosis (AUC = 0.869) than that of ACR TI-RADS classification alone (AUC = 0.756). CONCLUTIONS: Clinicians need to pay attention to the halo of nodules when distinguishing FTA from FTC. Notably, ACR TI-RADS combined with other nodule ultrasound features has superior predictive performance in diagnosis of FTC compared to ACR TI-RADS classification alone, thus can provide an important reference value for preoperative diagnosis of FTC.

Profiling of gene fusion involving targetable genes in Chinese gastric cancer.

BACKGROUND: Approximately half of all new cases of gastric cancer (GC) and related deaths occur in China. More than 80% of patients with GC are diagnosed at an advanced stage, which results in poor prognosis. Although HER2-directed therapy and immune checkpoint inhibitors have been somewhat successful, new drugs are still needed for the treatment of GC. Notably, several gene fusion-targeted drugs have been approved by the United States Food and Drug Administration for solid tumors, including GC, such as larotrectinib for NTRK fusion-positive cancers and zenocutuzumab for NRG1 fusion-positive cancers. However, gene fusions involving targetable genes have not been well characterized in Chinese patients with GC. AIM: To identify the profile of fusions involving targetable genes in Chinese patients with GC using clinical specimens and determine the distribution of patients with gene fusion variants among the molecular subtypes of GC. METHODS: We retrospectively analyzed gene fusion events in tumor tissue samples from 954 Chinese patients with GC. Clinicopathological characteristics were obtained from their medical records. Genetic alterations, such as single nucleotide variants, indels, amplifications, and gene fusions, were identified using a targeted sequencing panel containing 825 genes. Fusions were validated by fluorescence in situ hybridization (FISH) using break-apart probes. The microsatellite instability (MSI) status was evaluated using MSIsensor from the targeted sequencing panel data. Tumor mutational burden (TMB) was calculated using the total number of nonsynonymous mutations divided by the total genomic targeted region. Chi-square analysis was used to determine the enrichment of gene fusions associated with the molecular subtypes of GC. RESULTS: We found that 1.68% (16/954) of patients harbored 20 fusion events involving targetable genes. RARA fusions (n = 5) were the most common, followed by FGFR2, BRAF, MET, FGFR3, RET, ALK, EGFR, NTRK2, and NRG1 fusions. Two of the RARA fusions, EML4-ALK (E6:E20) and EGFR-SEPTIN14 (E7:E10), have been identified in other tumors but not in GC. Surprisingly, 18 gene fusion events were previously not reported in any cancer types. Twelve of the eighteen novel gene fusions included complete exons encoding functional domains of targetable genes, such as the tyrosine kinase domain of receptor tyrosine kinases and the DNA- and ligand-binding domains of RARA. Consistent with the results of detection using the targeted sequencing fusion panel, the results of FISH (fluorescence in situ hybridization) confirmed the rearrangement of FGFR2 and BRAF in tumors from patients 04 and 09, respectively. Genetic analysis indicated that the fusion genes were significantly enriched in patients with ERBB2 amplification (P = 0.02); however, there were no significant differences between fusion-positive and fusion-negative patients in age, sex, MSI status, and TMB. CONCLUSION: We characterized the landscape of fusions involving targetable genes in a Chinese GC cohort and found that 1.68% of patients with GC harbor potential targetable gene fusions, which were enriched in patients with ERBB2 amplification. Gene fusion detection may provide a potential treatment strategy for patients with GC with disease progression following standard therapy.