KMT2A Mutations and High Prevalence of dMMR-associated Mutational Signatures as Prognostic Indicators in Metastatic Colorectal Cancer.

The conventional treatment strategies for patients with metastatic colorectal cancer (mCRC) are predominantly guided by the status of RAS and BRAF mutations. Although patients may exhibit analogous pathological characteristics and undergo similar treatment regimens, notable disparities in their prognostic outcomes can be observed. Therefore, tissue and plasma samples from 40 mCRC patients underwent next-generation sequencing targeting 425 cancer-relevant genes. Genomic variations and canonical oncogenic pathways were investigated for their prognostic effects in association with progression-free survival (PFS) of these patients. We found that patients with BRCA2 and KMT2A mutations exhibited worse prognostic outcomes after chemotherapy-based treatment (univariate, P < 0.01). Further pathway analysis indicated that alterations in the homologous recombination pathway and in the KMT2A signaling network were also significantly associated with shortened PFS (univariate, P < 0.01). Additionally, mutation signature analysis showed that patients with higher proportions of defective mismatch repair (dMMR)-related mutational signatures. Had a worse prognosis (univariate, P = 0.02). KMT2A mutations (hazard ratio [HR], 4.47; 95% confidence interval [CI], 1-19.93; P =0.050) and dMMR signature proportions (HR, 3.57; 95% CI, 1.42-8.96; P = 0.007) remained independently associated with PFS after multivariate analysis and the results were further externally validated. These findings may enhance our understanding of this disease and may potentially facilitate the optimization of its treatment approaches.

Circulating memory PD-1+CD8+ T cells and PD-1+CD8+T/PD-1+CD4+T cell ratio predict response and outcome to immunotherapy in advanced gastric cancer patients.

BACKGROUND: Limited benefit population of immunotherapy makes it urgent to select effective biomarkers for screening appropriate treatment population. Herein, we have investigated the predictive values of circulating CD8+ T cells and CD8+T/CD4+T cell ratio in advanced gastric cancer patients receiving immunotherapy. METHODS: A retrospective cohort analysis of 187 advanced gastric cancer patients receiving sintilimab combined with oxaliplatin and capecitabine therapy in The Affiliated Xinghua People's Hospital, Medical School of Yangzhou University between December 2019 and February 2023 was conducted. The corresponding clinical outcomes of the variables were analyzed by receiver operating characteristic (ROC) curve, chi-square test, Kaplan-Meier methods and Cox proportional hazards regression models. RESULTS: The optimal cutoff values for percentages of CD8+ T cells, naive CD8+ T cells (CD8+ Tn) and memory CD8+ T cells (CD8+ Tm) expressing programmed cell death -1(PD-1) as well as PD-1+CD8+T/PD-1+CD4+T cell ratio were 21.0, 21.5, 64.3 and 0.669, respectively. It was found that the mean percentages of CD8+ T and CD8+ Tm expressing PD-1 as well as PD-1+CD8+T/PD-1+CD4+T cell ratio were significantly higher in responder (R) than non-responder (NonR) advanced gastric cancer patients associated with a longer progression free survival (PFS) and overall survival (OS). We also observed this correlation in programmed cell death-ligand 1(PD-L1) combined positive score (CPS) ≥ 5 subgroups. Univariate and multivariate Cox regression analyses demonstrated that lower CD8+ T and CD8+ Tm expressing PD-1 as well as PD-1+CD8+T/PD-1+CD4+T cell ratio were independent risk factors in advanced gastric cancer patients receiving immunotherapy plus chemotherapy. CONCLUSION: The circulating memory PD-1+CD8+ T cells and PD-1+CD8+T/PD-1+CD4+T cell ratio revealed high predictive values for response and prolonged survival outcomes in advanced gastric cancer patients receiving immunotherapy. Memory PD-1+CD8+ T cells and PD-1+CD8+T/PD-1+CD4+T cell ratio might be effective for screening benefit population of immunotherapy in advanced gastric cancer patients based on this preliminary evidence.

Copper-Catalyzed Synthesis of N-Fused Quinolines via C(sp3)-H Activation-Radical Addition-Cyclization Cascade.

A novel copper-catalyzed cyclization reaction for the synthesis of pyrazolo[1,5-a]quinoline, triazolo[1,5-a]quinoline, and pyrrolo[1,2-a]quinoline derivatives is described. The process is initiated by di-tert-butyl peroxide-mediated C(sp3)-H activation to generate the α-functionalized radical, which supervenes a cascade radical addition/cyclization sequence to access the N-fused quinolines in good yields with broad functional group tolerance.

Discovery of N-(2-oxoethyl) sulfanilamide-derived inhibitors of KAT6A (MOZ) against leukemia by an isostere strategy.

KAT6A has been identified as a new target for leukemia treatment. The histone acetyltransferase activity of KAT6A is essential for normal hematopoietic stem cell self-renewal, and mutations or translocations are regarded as one of the major causes of leukemia development. In previous studies, CTX-0124143 has been shown to be a class of KAT6A inhibitors with a sulfonyl hydrazide backbone. However, weak activity, poor selectivity and pharmacokinetic problems have hindered its clinical application. In this work, the N‒N bond in compound CTX-0124143 was replaced by an N-C bond, and the aromatic rings were replaced on both sides. Finally, we obtained Compound 6j. Compared to CTX-0124143, 6j showed a 16-fold stronger inhibition of KAT6A (0.49 µM vs. 0.03 µM) with high selectivity. In addition, 6j exhibited strong antitumor activity on four leukemia cell lines. Moreover, 6j showed significant improvement in metabolic stability and pharmacokinetics in vivo and in vitro. In conclusion, 6j shows excellent potential as a promising anti-leukemia drug candidate.

Synthesis of Isoxazoles via One-Pot Oxidation/Cyclization Sequence from Propargylamines.

A facile strategy for the synthesis of isoxazoles has been efficaciously developed, which involves oxidation of propargylamines to the corresponding oximes followed by CuCl-mediated intramolecular cyclization of the latter. This protocol shows a straightforward way to construct a series of isoxazole cores with a wide range of functional group compatibility. Meanwhile, a gram-scale experiment and synthetic applications can be successfully operated.

Construction of a Protoberberine Alkaloid Skeleton via the Palladium-Catalyzed α-Arylation-Amide Formation Cascade.

In this work, we report the strategy of one-pot synthesis of protoberberine alkaloid derivatives via palladium-catalyzed cascade α-arylation and cyclization, which can afford the target molecules in moderate to excellent isolated yields using commercially available raw materials under solvent-free conditions. This protocol provides an efficient and convenient path to multisubstituted protoberberine derivatives. In addition, it can directly afford natural alkaloids.

Design, synthesis and biological evaluation of tanshinone IIA-based analogues: Potent inhibitors of microtubule formation and angiogenesis.

We report the structural optimization of tanshinone IIA, a natural product which possesses anti-tumor properties but low water-solubility, weak antiproliferative activity and poor PK properties. A new series of ring A/C/D modified tanshinone analogues were synthesized and studied for their antiproliferative capacities against six human cancer cell lines. SAR study revealed that ring A cleavage of tanshinone IIA led to improved anti-cancer activity. Introduction of a methoxy group to the phenyl ring could enhance the anti-cancer activity even further. Compound 2f with methoxy group at C-8 position was selected as an early lead with IC50 values of 0.28-3.16 µM against six tested cell lines. 2f could bind to tubulin colchicine site, inhibit tubulin assembly and disrupt the normal formation of microtubule networks. Cellular mechanistic studies revealed that 2f induced apoptotic cell death of A549 cells in a dose-dependent manner. In vitro investigations showed that 2f impeded the tubule-formation of HUVECs and potently inhibited the proliferation, migration and invasion of A549 cells as well as HUVECs. Furthermore, the in vivo anti-angiogenic effect of 2f was confirmed via a zebrafish model test. The satisfactory physicochemical property and metabolic stability of 2f, as well as improved water-solubility, further suggested that 2f could serve as a promising tubulin inhibitor and anti-angiogenic agent.

TfOH-Promoted Decyanative Cyclization toward the Synthesis of 2,1-Benzisoxazoles.

A novel solvent-free, TfOH-promoted decyanative cyclization approach for the synthesis of 2,1-benzisoxazoles has been developed. The reactions are complete instantly at room temperature and result in the formation of the desired 2,1-benzisoxazoles in a 34-97% isolated yield.

Discovery of Dosimertinib, a Highly Potent, Selective, and Orally Efficacious Deuterated EGFR Targeting Clinical Candidate for the Treatment of Non-Small-Cell Lung Cancer.

Osimertinib is a highly potent and selective third-generation epidermal growth factor receptor (EGFR) inhibitor, which provides excellent clinical benefits and is now a standard-of-care therapy for advanced EGFR mutation-positive non-small-cell lung cancer (NSCLC). However, AZ5104, a primary toxic metabolite of osimertinib, has caused unwanted toxicities. To address this unmet medical need, we initiated an iterative program focusing on structural optimizations of osimertinib and preclinical characterization, leading to the discovery of a highly potent, selective, and orally efficacious deuterated EGFR-targeting clinical candidate, dosimertinib. Preclinical studies revealed that dosimertinib demonstrated robust in vivo antitumor efficacy and favorable PK profiles, but with lower toxicity than osimertinib. These preclinical data support further clinical development of dosimertinib for the treatment of NSCLC. Dosimertinib has received official approval in China to initiate the phase I clinical trial (registration numbers: CXHL2000060 and CXHL2000061).

Synthesis and Biological Activity Study of Tanshinone Derivatives: A Literature and Patent Review.

Tanshinones are a class of bioactive compounds present in the Chinese herbal medicine Danshen (Salvia miltiorrhiza Bunge), containing among others, abietane diterpene quinone scaffolds. Chemical synthesis and biological activity studies of natural and unnatural tanshinone derivatives have been reviewed in this article.

Mechanistic Insight into Antiretroviral Potency of 2'-Deoxy-2'-ß-fluoro-4'-azidocytidine (FNC) with a Long-Lasting Effect on HIV-1 Prevention.

In preclinical and phase I and II clinical studies, 2'-deoxy-2'-ß-fluoro-4'-azidocytidine (FNC) displays a potent and long-lasting inhibition of HIV-1 infection. To investigate its mechanism of action, we compared it with the well-documented lamivudine (3TC). Pharmacokinetic studies revealed that the intracellular retention of FNC triphosphate in peripheral blood mononuclear cells was markedly longer than that of the 3TC triphosphate. FNC selectively enters and is retained in HIV target cells, where it exerts long-lasting prevention of HIV-1 infection. In addition to inhibition of HIV-1 reverse transcription, FNC also restores A3G expression in CD4+ T cells in FNC-treated HIV-1 patients. FNC binds to the Vif-E3 ubiquitin ligase complex, enabling A3G to avoid Vif-induced ubiquitination and degradation. These data reveal the mechanisms underlying the superior anti-HIV potency and long-lasting action of FNC. Our results also suggest a potential clinical application of FNC as a long-lasting pre-exposure prophylactic agent capable of preventing HIV infection.

A Randomized, Open-Label, Controlled Clinical Trial of Azvudine Tablets in the Treatment of Mild and Common COVID-19, a Pilot Study.

Coronavirus disease 2019 (COVID-19) has spread worldwide. To date, no specific drug for COVID-19 has been developed. Thus, this randomized, open-label, controlled clinical trial (ChiCTR2000029853) was performed in China. A total of 20 mild and common COVID-19 patients were enrolled and randomly assigned to receive azvudine and symptomatic treatment (FNC group), or standard antiviral and symptomatic treatment (control group). The mean times of the first nucleic acid negative conversion (NANC) of ten patients in the FNC group and ten patients in the control group are 2.60 (SD 0.97; range 1-4) d and 5.60 (SD 3.06; range 2-13) d, respectively (p = 0.008). The mean times of the first NANC of four newly diagnosed subjects in the FNC group and ten subjects in the control group are 2.50 (SD 1.00; range 2-4) d and 9.80 (SD 4.73; range 3-19) d, respectively (starting from the initial treatment) (p = 0.01). No adverse events occur in the FNC group, while three adverse events occur in the control group (p = 0.06). The preliminary results show that FNC treatment in the mild and common COVID-19 may shorten the NANC time versus standard antiviral treatment. Therefore, clinical trials of FNC treating COVID-19 with larger sample size are warranted.

Synthesis and anti-CVB3 activity of 4-amino acid derivative substituted pyrimidine nucleoside analogues.

Seven novel 4-amino acid derivative substituted pyrimidine nucleoside analogues were designed, synthesized, and tested for their anti-CVB3 activity. Initial biological studies indicated that among these 4-amino acid derivative substituted pyrimidine nucleoside analogues, 4-N-(2'-amino-glutaric acid-1'-methylester)-1-(2'- deoxy-2'-ß-fluoro-4'-azido)-furanosyl-cytosine 2 exhibited the most potent anti-CVB activity (IC50 = 9.3 µM). The cytotoxicity of these compounds has also been assessed. The toxicity of compound 2 was similar to that of ribavirin.

Identification of Clausine E as an inhibitor of fat mass and obesity-associated protein (FTO) demethylase activity.

The alkaloids containing a carbazole nucleus are an established class of natural products with wide range of biological activities. A combination of thermodynamic and enzymatic activity studies provides an insight into the recognition of Clausine E by the fat mass and obesity-associated protein (FTO). The binding of Clausine E to FTO was driven by positive entropy and negative enthalpy changes. Results also indicated that the hydroxyl group was crucial for the binding of small molecules with FTO. The structural and thermodynamic information provides the basis for the design of more effective inhibitors for FTO demethylase activity.

Total Synthesis of (+)-Aspidospermidine.

A facile asymmetric total synthesis of (+)-aspidospermidine has been developed, which is accomplished in 11 steps in an overall yield of 9.6%. Key steps involve a palladium-catalyzed enantioselective decarboxylative allylation to install the quaternary carbon stereocenter and a highly efficient reductive amination-carbonyl reduction-dehydration-intramolecular conjugate addition cascade to build the cis D-ring.

Cardioprotection of (±)-sodium 5-bromo-2-(α-hydroxypentyl) benzoate (BZP) on mouse myocardium I/R injury through inhibiting 12/15-LOX-2 activity.

(±)-Sodium5-bromo-2-(α-hydroxypentyl) benzoate (brand name: brozopine, BZP, 1a), derived from L-3-n-butylphthalide (L-NBP), has been reported to protect the brain from stoke and has been approved by CFDA in Phase I-II clinical trials. However, it remains to be investigated whether 1a may exhibit any cardioprotective effect on ischemia-reperfusion (I/R) injury. In the current study, C57BL/6 and ICR mice were pretreated with 1a, and myocardium I/R were then performed. We found that 1a not only significantly reduced the infarct size and improved cardiac contractile function after acute MI/R in both species, but also protected hearts from chronic MI-related cardiac injury. Mechanically, we found that 1a physically binds to 12/15-LOX-2 using molecular docking. The shRNA-mediated 12/15-LOX-2 knockdown almost completely blocked the protective effect of 1a. Our findings, for the first time, strongly indicate that 1a may serve as a potent and promising cardioprotective agent in treatment of I/R related injury, at least partially through targeting 12/15-LOX-2.

Targeting Tubulin-colchicine Site for Cancer Therapy: Inhibitors, Antibody- Drug Conjugates and Degradation Agents.

Microtubules are essential for the mitotic division of cells and have been an attractive target for antitumour drugs due to the increased incidence of cancer and significant mitosis rate of tumour cells. In the past few years, tubulin-colchicine binding site, as one of the three binding pockets including taxol-, vinblastine- and colchicine-binding sites, has been focused on to design tubulin-destabilizing agents including inhibitors, antibody-drug conjugates and degradation agents. The present review is the first to cover a systemic and recent synopsis of tubulin-colchicine binding site agents. We believe that it would provide an increase in our understanding of receptor-ligand interaction pattern and consciousness of a series of challenges about tubulin target druggability.

Design, synthesis, and biological evaluation of novel 2'-deoxy-2'-fluoro-2'-C-methyl 8-azanebularine derivatives as potent anti-HBV agents.

Hepatitis B virus (HBV) is a global health problem requiring more efficient and better tolerated anti-HBV agent. In this paper, a series of novel 2'-deoxy-2'-fluoro-2'-C-methyl-ß-d-arabinofuranosyl 8-azanebularine analogues (1 and 2a) and N4-substituted 8-azaadenosine derivatives (2b-g) were designed, synthesized and screened for in vitro anti-HBV activity. Two concise and practical synthetic routes were developed toward the structural motif construction of 2'-deoxy-2'-fluoro-2'-C-methyl-ß-d-arabinofuranosyl 8-azainosine from the ribonolactone 3 under mild conditions. The in vitro anti-HBV screening results showed that these 8-azanebularine analogues had a significant inhibitory effect on the expression of HBV antigens and HBV DNA at a concentration of 20 µM. Among them, halogen-substituted 8-azaadenosine derivative 2g displayed activities comparable to that of 3TC. In particular, 2g retained excellent activity against lamivudine-resistant HBV mutants.

Identification of Natural Compound Radicicol as a Potent FTO Inhibitor.

The fat mass and obesity-associated protein (FTO), as an m6A demethylase, is involved in many human diseases. Virtual screening and similarity search in combination with bioactivity assay lead to the identification of the natural compound radicicol as a potent FTO inhibitor, which exhibits a dose-dependent inhibition of FTO demethylation activity with an IC50 value of 16.04 µM. Further ITC experiments show that the binding between radicicol and FTO was mainly entropy-driven. Crystal structure analysis reveals that radicicol adopts an L-shaped conformation in the FTO binding site and occupies the same position as N-CDPCB, a previously identified small molecular inhibitor of FTO. Unexpectedly, however, the 1,3-diol group conserved in radicicol and N-CDPCB assumes strikingly different orientations for interaction with FTO. The identification of radicicol as an FTO inhibitor and revelation of its recognition mechanism not only opens the possibility of developing new therapeutic strategies for treatment of leukemia but also provide clues for elucidation of the acting mechanisms of radicicol, which is a possible clinical candidate worth in-depth study.

Design, synthesis, and biological evaluation of new 1,2,3-triazolo-2'-deoxy-2'-fluoro- 4'-azido nucleoside derivatives as potent anti-HBV agents.

Novel drugs are urgently needed to combat hepatitis B virus (HBV) infection due to drug-resistant virus. In this paper, a series of novel 4-monosubstituted 2'-deoxy-2'-ß-fluoro-4'-azido-ß-d-arabinofuranosyl 1,2,3-triazole nucleoside analogues (1a-g) were designed, synthesized and screened for in vitro anti-HBV activity. At 5.0 µM in the cellular model, all the synthetic compounds display activities comparable to that of the positive control, lamivudine at 20 µM. Of the compounds tested, the amide-substituted analogue (1a) shows the most promising anti-HBV activity and low cytotoxicity in the cell model. In particular, it retains excellent activity against lamivudine-resistant HBV mutants. In duck HBV (DHBV)-infected duck models, both the serum and liver DHBV DNA levels (67.4% and 53.3%, respectively) were reduced markedly by the treatment with 1a. Analysis of the structure of HBV polymer/1a-triphosphate (1a-TP) complex shows that 1a-TP is stabilized by specific van der Waals interactions with the enzyme residues arising from 4-amino-1,2,3-triazole and the 4'-azido group.